http:

Many thanks to author, John Teagle, for the use of his SUNN articles.

By: John Teagle & John Sprung
A standard in all of the music world for over five decades, Fender amps have been a major part of rock, country, jazz, blues, pop, and more. From K&F amp of 1945 to today, this book covers the amazing history of Fender's contribution to the amplifier. Featuring: complete details and specs on every model, rare catalog and ad reprints, hundreds of close-up photos, and a 40 page color section. 256 pgs, Softbound............$34.95

While you're at it check out John Sprung's site too!

//www.standelamps.com/support/schematics/index.html
 

My heart-felt appreciation to "Vintage Guitar" Magazine for their support in this project as well. If you're not already a subscriber, you should be. Click on the link above and become a happy camper. :-) Also, where noted, there are still copies of this great article--INCLUDING all of the pictures-available from Vintage Guitar Magazine  

Sunn's Big Guns and the Jimi Hendrix Experience

This one's from the Nov. '98 issue (unavailable as a backissue).

By John Teagle


 After World War II, amplifiers for musical instruments just kept getting louder and louder.  High-efficiency permanent-magnet speakers, more powerful tubes and transformers, and new circuit designs all helped the units develop more output.  Fender's 50-watt fixed-bias Bassman, four-power-tube, 80 to 100-watt output Twin, and ported JBL 15" Showman bottom all were influential on the Sunn Coliseum PA, which upon requests from guitarists and bassists became the 1000 Series and the 2000S musical instrument amps.  Many of the English companies would follow Sunn's lead by using four Genelex Gold Lion KT88 power tubes, including the 200-watt Marshall Major, HiWatt 200, Sound City 200, and Orange 200.  At this point, tube amps had gone about as far as they were going, at least for guitar.
 
Coliseum PA System

Sunn introduced its powerful Coliseum PA system ca. 1965 and it gained favor with bands (like the Beach Boys) for its high-fidelity, full-frequency reproduction.  The speaker system included left and right side stacks consisting of two 15" JBL 130AS cone speakers for the bass with  JBL crossovers built into the backside of the 42" X 24" X 15" cabinet.  On top sat a separate cabinet housing a JBL 375 midrange compression driver coupled to a JBL horn/lens, giving wide dispersion of sound.  The high frequencies were handled by a JBL 075 "bullet" tweeter built into the top corner of the 2 X 15" cabinet's baffleboard.  This passive three-way system was about as good as a speaker system got until active crossovers became popular in the '70s.
The head is most important to this story, as guitarists and bassists shunned the expensive and inappropriate full-range speakers in favor of multiple-cone speaker cabinets with limited high-frequency response.  It was the powerful stock Coliseum head Jimi Hendrix used early-on (early '68) in place of Sunn's suggested 60-watt 100S head, with the company supplying 4 X 12" cabinets to suit his preference (collectors take note).  These heads were designed to be high-fidelity but like any tube amp, especially one designed to accept low-output microphones, they would break up when pushed.  The Coliseum used four KT88 power tubes in a push/pull ultralinear circuit.  The transformers were from the large Dynaco mono blocks.  It's interesting the amps were only rated at 120 watts RMS, because everyone else claimed 200 watts from the same arrangement.  It's probable the transformers weren't large enough to develop the extremely high plate voltage necessary for full power, or that the ratings were on the conservative side (they gave the peak power with negligible distortion as 280 watts).

The individual volume controls for each of the four channels were coupled to a Master Volume control, although the people using these as guitar heads probably put both on 10.  Having a separate preamp tube for each channel would have allowed players to jump channels and get a fuller sound at lower volumes, as would become popular with two-channel Marshalls (the later single-channel instrument Sunn models had all four inputs ganged to a single preamp).  A total of three twin-triode 12AX7s handled the four input stages, leaving two stages for additional gain, a 6AN8 acted as the phase inverter and a pair of 5AR4 rectifiers supplied the juice.  Separate bass and treble controls rounded out the features.
Price for the entire system in early '68 was a whopping $3,695, without covers.  By April 1970, the JBL 075 bullet tweeter and its crossover network were gone and the price dropped to $3,495.  In the early '70s, Sunn expanded heavily into PA manufacturing, offering numerous solidstate heads of varying wattage, with the tube Coliseum being retired.

1000S, 1200S, and 1500S Guitar Amps

1000S: Following interest in using the Coliseum as a guitar amp, the engineers designed dedicated heads for guitar and bass. They officially joined the line sometime in mid '68, as they are listed on the revised April '68 pricelist, but not the original (the '68 catalog, undoubtedly available by the Summer NAMM show, featured all these amps).  At the top of the line was the 1000S system, featuring vibrato (actually tremolo) and reverb.  Gone from the Coliseum were the mic inputs and master volume control, so these guys were probably clean up to earsplitting levels.  Controls were volume, bass, treble, contour, depth and rate for the tremolo, and reverb.  Like the rest of the amps in this series, tubes included four KT88s for the power amp, a 6AN8 for the phase inverter, a 7025 twin triode for the preamp and twin GZ-34 rectifiers. An additional 12AU7 on the 1000S handled the reverb. By this time, Sunn had its own D15S speaker by JBL and the 1000S bottoms had two of them, plus a JBL LE100S exponential horn and driver (and crossover) for the highs.  Buck Munger tells how the engineers were sold on high-fidelity reproduction and it shows in the choice of speakers for the top of the line instrument amp.  Prices were $2,300 for the head and two bottoms (as used by the touring bands) or $1,495 with a single bottom.

1200S and 1500S: Expanding on the English 4 X 12" bottom by 50 percent, a  pair of 6 X 12" cabinets with the new "heavy duty Sunn Guitar Transducers" were stock for the 1200S.  The 1500S used twin JBL D15S speakers.  Missing from the 1000S head were the reverb and tremolo circuits and the 12AU7 tube.  Otherwise, all these amps were nearly identical, having 10" X 30" X 9 1/2" boxes for the heads and 48" X 30" X 15" cabinets.  Prices were a cool $1,500 for the 1200S with two bottoms ($2,590 with JBL D123Fs in '70) and $1,940 for the 1500S set.  The 1970 catalog shows the 1500S gone, the 1000S speakers replaced by the hornless 2 X 15" cabinet and both the 1000S and 1200S heads having reverb and tremolo.  A number of solid state devices were used in the circuit for these effects.  Perhaps because Sunn wasn't fully utilizing the expensive KT88s, they switched to Tung-Sol 6550s, which also put out 120 watts in these amps (a schematic dated 1969 shows this change). Chances are good this later setup gave a bit more distortion when cranked.  These amps were superseded by the 150-watt Model T amp in the early '70s.

2000S Bass Amp

Affectionately referred to as the Noel Redding amp by cognoscenti, the 2000S was similar to the 1000 series amps, fitted with four KT88s in the early days before switching to 6550s (both rated at 120 watts RMS, 280 peak).  These were joined by the 6AN8, 7025 and twin GZ-34s, as seen on the original 1200S and 1500S.  Differences in the voicing of tone controls and the addition of a Bass Boost switch (officially added in May '69 but probably tested earlier in the year) separate the bass model from the guitar.  Using JBL D140F bass speakers added a bit more thump in the bottom octave, which the rear-loaded folded-horn cabinet design was able to translate into usable decibels (some cabinets are not capable of reproducing deep bass, no matter what speaker is used).  Sunn had a reputation for its rugged cabinets, which came stock with casters.  Total weight for a complete 2000S set was over 300 pounds! Like the 1000 series, the 2000S was not cheap, costing an even $2,000 in '68.

 Test Run 2000S

At the invitation of Al Romano, a New York collector, VG was able to put a full 2000S set through the paces (outdoors of course).  Using the late Felix Pappalardi's '63 Thunderbird bass, we filled the Hudson River Valley with a blast of classic licks, amp settings at the requisite 10. The instrument and bass rig have been somewhat reunited, as all the pieces came from the Mountain organization (the head from Felix and the bottoms traced back to Charles Lane Rehearsal Studios, Manhattan, where they reportedly had been sold to pay an outstanding balance).

Numerous features separate this set from a stock model, including the addition of a 120/240V switch for world travelers, a slave output with a mysterious switch allowing a number of heads to be controlled from a single set of controls, and an additional output jack.  The handwritten "Sugar" relates to a post-Mountain Pappalardi bassist (Felix had switched to guitar) and the additional pilot light in the middle of the front panel was a Mountain trademark.  In an interview for Guitar Player  (April '72), Pappalardi refers to the head. "It was souped up some more by our Tom Lyle, but I really don't know what he did.  Something to the top, I think.  I'm really not into all that electronic thing.  As long as I have the bark, the attack that I like, everything's fine."

Like many VG readers, the owner of this set is obviously fanatical about his gear (he also owns a mint Olympic White '65 Strat. "...just like Hendrix's early shows," Ace Frehley's flamey '59 Les Paul Standard, and numerous '60s Marshalls).  But when he tried to convince me the amplifier's cabinet says "Mountain" on it, I honestly thought he was bonkers.  It seemed no matter which angle we looked at it, I couldn't see it and, of course, he could!  He assured me it was there, pulling  out lights and illuminating the top surface from all angles.  Finally, he took it outside, sprayed water on the top and it magically appeared!   Pictures were taken from numerous angles, with the results ranging from blank black to a legible word.  Cosmic, dude!

he grille on the head has the close-pattern material used on all the Sunn stuff until late-'69, while the bottoms are dressed in the later Fender-style cloth.   It seems obvious the speaker cabinets once were in the Mountain camp, as they are numbered on the bottom in large white numbers for inventory and transport and have a small black label stamped over the numbers with references to Windfall, the band's record label.

It's wise to always be skeptical about celebrity instruments, but this would have been too much to bother with in a forgery.   Through the rumor mill (a former owner), it was suggested the cabinets were recovered by Sunn before the identifications were added.  After talking to Sunn's A&R man from the era and hearing stories about the factory regularly doing makeovers on equipment from their artist loaner pool, it seems possible.  They wouldn't have wanted these promotional items to look ratty, as was inevitable in touring situations (particularly on heavy items).

Which brings us to a "Jimi Hendrix slept here" story that immediately sent up the red flags.  Could some of the Mountain gear have been leftovers from Hendrix tours?  Numerous guitars and amps have reportedly been passed on to musicians from J.H. himself and if the A&R people thought it was going to a good home, they could easily have looked the other way.
 
In the November '72 Guitar Player, a columnist writes, "The sound system Felix uses is the Sunn equipment he claims was designed for Jimi Hendrix."
 
This can be taken a number of ways, and since it is a bass rig, it would have been for Redding, not Hendrix (post-Experience bassist Billy Cox's association with Marshall ended the JHE/Sunn collaboration).  Having the grille of the earlier models, but the Bass Boost switch and 6550s of the later version, place it early-to-mid '69, so it could have been one of Redding's last Sunns.  By then, Hendrix was known to go over Redding's original bass tracks in the studio, so the time frame is right.
Longtime Pappalardi/Windfall employee Richie DeMartino, who was with Mountain on a daily basis, remembers Hendrix giving Pappalardi "...a whole room full of Sunns," including the head discussed here. 

So how does it sound?  Cranked, it does a certain style amazingly, with endless sustain but a clarity to individual notes, as on the best guitar amps.  Romano ran through the complete catalog of Mountain classics (he studied with West as a teenager, see October '80 Guitar Player for a photo) and it seems obvious Felix's lyrical single-note playing would not have been the same with a modern rig.  On the other hand, playing any combination of notes sent the amp into power chord heaven, but not like a Fuzztone; magical in its own way, although certainly not for everybody.  The bottoms performed confidently and solidly with no rattle.
 
Sad in a way, very few players can consistently get away with the volume required to bring out the character of this amp's power tube distortion, making it impractical for everyday use.  Since the 2000S amps were extremely expensive and used almost exclusively by professionals, they are today quite rare.  As for using it for fun, how often and how long can you get away with playing really loud in your backyard?  Playing it indoors would rattle the house down and in a soundproof rehearsal room, you'd go deaf!  If you owned your own theater and had a really long guitar cord...another tube-powered dinosaur on its way to extinction.

Thanks to all the folks who helped this month; Noel, Mrs. R, Buck, NiteBob, Richie, Conrad, and anybody I've forgotten.  All catalogs and photos courtesy of the author.

Pt. II
Talking Sunn with Conrad Sundholm.  
This is from the January '99 issue. (which is available as a back issue).

By John Teagle


Sunn as a brand name came from the Sundholm brothers of Portland Oregon,
who started the company in 1965.  It's interesting that the musician
brother, Norm, left music for real estate at the end of the '60s and the
technical brother, Conrad, who taught secondary education after
graduating from college in '61, continued in the musical equipment
business, where he's still active today.  Conrad Sundholm built complex
rear-loaded folded-horn speaker cabinets (as well as boats) in his spare
time and, like many hi-fi enthusiasts of the '50s and '60s, built his
own stereo from a kit, with no formal electronics background.  Here are
his recollections of the early days of Sunn Musical Equipment Company.
We will profile the amps next month.

Vintage Guitar: Let's start with the prototypes.

Conrad Sundholm: Our first bottom was a bass reflex cabinet built for my
brother, Norm, who was the bass player for the Kingsmen.  He'd been
working at a music store (Burke Arens Music Co.) and was taking Fender
cabinets and modifying them, making them bass reflex (ported).  And he
was using Bogen PA amplifiers along with these (for more on Norm and the
Bamco brand see Amps - The Other Half Of R&R ,by Richie Fliegler).
Then I built him a cabinet I had from the twilight zone - from my
sleep!  Things weren't real scientific back then, not like today with
the computers.  So I built this cabinet and sent it to JBL and had Dick
May, their engineer, check it.  He said it was dead on.  It was kind of
a rear-loaded folded-horn arrangement with a port across the middle and
the folded horn up behind the speaker, on either side of the two
speakers, which became the 2-30/C60.  The only changes in the design
were to make it more manufacturable, but that first one was a real
beast.

VG: Well, as musician/roadies, we cursed you guys for years because
those standard 2 X 15" cabinets were heavy!  How about the early amps?

CS: I used a DynaKit power amp, the Mark III, and their preamp, the
PAS-1.  I hung the preamp from the top at the rear and mounted the amp
on the bottom.  This was a straight hi-fi system - very linear, very
low-distortion, but it really didn't have the right frequency response
in the preamp, it was a little flat.  Norm had a Gibson EB-O bass and it
had a lot of low end and whenever he'd go out on a job there'd be this
enormous low-end energy no one had experienced before, so it created
quite a stir.  We made the decision to go into manufacturing because it
turned out so good.

VG: What year did Sunn, as a company, get started?

CS: The earliest Sunn amps were around '65.  I borrowed $1,300 from the
Portland Teachers credit union to buy plywood, tolex, and JBL
loudspeakers.  These were from a local dealer and at that time, JBL had
these fair trade agreements with all its dealers so no one would be
undercutting.  So this guy discounts them to me and ends up losing the
JBL line, I found out later.  The local rep found out somehow and then
he started calling on us directly and we ended up buying OEM from JBL
with the help of this rep!
I quit teaching the next spring - 1966.  My dad had a sizable shop in
the back of his place and that's where we built the first production
models.  I had a phone out back and when it would ring, we'd have to
shut off all the saws and take the orders.  My first employee was Mick
Vanwinkle, a student of mine from high school, and then Jim Peterson was
hired full-time.

VG: Were either of these guys electrical?

CS: No.  My friend, Gene Matheny, was building the preamps and I was
assembling the power amps; we'd use the chassis of the Mark III and then
our own for the preamp.  Matheny was kind of an electronics wizard and I
had him take the PAS-1 circuit and modify it to get more of that "hole
in the middle" [midrange cut].  I think we modified the tone controls a
bit and added some switches.  So we were building the sheet metal
chassis for the new circuit and using the Mark III power amp.  Later we
also used the Mark IV, which was smaller, it used two EL34s for the
output stage, instead of KT88s, and we used that for the single-speaker
versions.  But the JBL loudspeakers were so efficient it didn't take a
lot of power to run.

VG: Any early users readers might recognize?

CS: Let's see, Mike Mitchell of the Kingsmen had a real early one;
that's when we discovered the circuit wasn't any good for guitar
(laughs).  There was a group up here, the Wailers (check out "Tall Cool
One," "High Wall," etc.), with Kent Morrell and Buck Hornsby; Buck had a
bass amp and Kent was the organ player.  I took his Hammond M3 and
modified it, cut it down, and moved the tone generator behind the
keyboard and had some chrome legs made.

VG: What did he use for an amp?

CS: He had a Leslie, I think it was a 122 and I took it and ripped all
the moulding off and rounded off the edges, then covered it with tolex!
Then I put a JBL 375 (high-frequency driver) in there and a JBL 15" and
he had a loud Leslie!  That was him standing with a finger in the air on
the cover of our earliest literature.

VG: How big was your line at the time?

CS: We had the 100S for guitar, with the D130S and the horn, and the
200S for the bass with two D140s.  Actually, we had the 2-30/C60
cabinet, which became the 2-40/C60 when we started to use D140 speakers
and then we had a 1-40/C60 which was half a cabinet with a smaller amp.
Later we had what was called the Spectrum and they used the D130 in a
reflex cabinet.
We quit buying the Dynakits and began using our own full chassis, so the
preamp and tone controls and output stages were all together, but it was
still basically the Dynaco circuits.  We were buying some parts, like
transformers from Dyna, but later found their supplier and started
buying direct.   

VG: Were any of these amps in the red covering I've heard about?

CS: The first units were black truck vinyl, and the logo nameplate was
gold with black silkscreening.  And on a dozen or more of the first
units, I took a little red nail polish and put a nose on the sun, the
logo had a little face.  The 100S had a colored strip down each side,
some were red and I think some were green.  You know how the Kustom amps
were naugahyde and some were colored?  We used that material on the
sides. But everything else was black.  There was a time before I used the tolex
material you see on most of the amps, I used a vinyl used on Pullman car
seats, that was almost a paisley pattern, but it was black.

VG: Any other oddball stuff out there collectors should know about, so
people don't strip the covering because they don't think it's original?

CS: We used some expanded vinyl on some of them, that foamy, soft stuff,
but it didn't hold up at all.  It was kinda cushy.  You know, Norm's
first amp was covered with that stuff.  And then everybody was using
Tolex from General Tire.  They sent us a number of patterns and we chose
one that became our standard.
I should mention there was one woman, Bert (Bertha) Gooding, who covered
just about every cabinet we built.  She later had a helper.  She also
did the slip covers.  She was cantankerous, but was an absolute master
of covering the cabinets.  She had no patience for anyone who wasn't
performing.  I often think of her - she was a hard worker and got a lot
of complaints from the other employees!

VG: Well, you had a lot of musicians working for you, right?  So she
probably kept them in line...

CS: Like oil and water (laughs).

VG: You'd have gotten no work from them without her!  There's this image
of the factory as a bunch of hippie kids sitting around playing electric
guitars real loud.

CS: Not really.  There were a few, but all the people doing the
soldering and wiring were highly experienced, most were former
Tektronics employees, building O-scopes and test equipment...   

VG: Let's get back to your dad's shop.

CS: So, we're at my dad's shop and starting to sell stuff on the East
coast, it was almost like "a prophet is without honor in his own
country."  All of our stuff was going east of the Mississippi.  We
rapidly outgrew that place, so we started to look for another facility
and there was a guy in an area near us, Tualitin, who'd had a
recreational swimming pool open to the public, and he wanted to get out
of the business.  When we looked at it he said, "I'll tell you what
we'll do.  Let's knock a hole in the wall and fill the pool with sand
and cover it up." 
So that's what we did!  We had a little front office and all.  That was
around '66/'67.  So we went to L.A. and got some new equipment and then
we went to the NAMM show and ended up with about nine months worth of
backorders.  Rock and roll was just going crazy.  We ended up as fierce
competition to Fender and Standel and the others; when we started to get
orders for a dozen amps at a time from E.U. Wurlitzer in Boston and
Marvin Kay's Music, in Florida, I was floored.

VG: Was Norm active in the company?

CS: Yeah, he was.  After the Kingsmen he came off the road and became
involved full-time, in the marketing.

VG: So he wasn't in the factory cutting wood?

CS:  No, no.  But by that time, neither was I.  He left around '69.  We
had a difference in philosophy and work ethic, and that was a point of
frustration.  I don't want this to sound negative; he was frustrated,
too.  So I bought him out and he went into real estate.

VG: Was a lot of your early success with PA systems?

CS: Well, I think our first PA was for the Beach Boys.  They wanted a
custom-built system, better than anything else out there.  So I used the
2 X 15" cabinet and then we had a separate cabinet that sat on top that
and housed the 375 driver and the horn.  And then we had the ring
radiating driver (075) in the big cabinet, so it was a three-way
system.  It was an incredible setup.  I think it used an N1200 and maybe
a 7500 crossover.

VG: In an earlier article, I suggested these started around '65, but now
it seems more like '66?

CS: Yeah, it was first called the Beach Boys PA and it had a
four-channel passive mixer in a box with a Mark III amplifier.  That was
the head, with the four-channel Switchcraft mixer.  We built it, checked
it out, and within a couple of hours I was on a plane to Salt Lake
City.  They were performing at the Lagoon Amusement Park and I had
trouble finding someone to cart the stuff out there.  The band was
waiting to perform, but we got there and got set up and they ended up
buying it; took it with them.

VG: How did that design end up as the Coliseum PA, with four KT88s and
separate, active preamps.

CS: Basically, all we did was double up the outputs on the Dyna
circuitry and beef up the power supply and the output transformer.  We
had a few engineers on staff by that time, but I don't recall who
actually designed it.  Conceptually, it was my idea; "We need more
output."

VG: And that led to the 1000, 1200, 1500, and 2000S big boys.

CS: Which became the Model T after I left.  We had a 4 X 15" cabinet,
double-wide, and when we first fired it up in the plant we were really
excited!  That was an awesome system.  By that time we'd expanded the
plant and had a separate shipping area where we could try things out.

VG: How did you get into solidstate amps?

CS: We'd hired Bob Tenyck, who'd worked for Ampeg and had his own
solidstate line back East.  He designed our Orion amp, which really hurt
the company financially, our big move into solidstate high-power.
Acoustic was starting to hurt us.  They didn't have the low-end, but man
were they loud!  But we had a lot of field failures, catastrophic
failures in the output stage.  I think we had about 125 in the field and
they started failing, so we recalled what we could.  They had a
vertically striped grillecloth and had the power amp in the speaker
bottom.

VG:  Like Acoustic and Fender's Super Showman, which actually isn't a
bad idea, especially back then when you did not mic up any of the
instruments, you had to cover everything with your stage volume.

CS:  And you know doing it that way, the sound is actually better
because you don't mix up the instruments with the vocals.

VG:  And you don't get the smearing from stuff hitting your brain from
three different sources, getting it offstage and then from the left side
stack and then from the right.  If I want to hear somebody, I run right
up to the front of the stage and hear it coming right out of their amp.

CS:  I've always wanted to put a 4 X 12" cabinet in each PA stack, have
a separate submix for it, and a separate setup for the kick drum so it
doesn't modulate everything else and then have the vocals separate.  But
anyway, right after that we did the Coliseum Series, just before I left
the company.

VG: Meaning the solidstate Coliseums?

CS: Yeah.  After the Orion failure we brought in Dick McCloud, who'd had
solidstate experience with Tektronics, who was a real guru/genius.  He
didn't come with the company, but we utilized his services.  We lost a
lot of money on the Orion because we'd invested in tooling and all the
inventory.  It was a big hit to the company, when all the profits were
going back into the growth.  Then a recession hit in 1970, so things got
a little rough.  But the Coliseum series, that included the bass amp
used by the Who, was a unique preamp circuit because each of the tone
controls was a separate preamp.  You could turn it all the way off, so
you had ultimate tone control.  A lot of versatility - you could turn
the midrange off or turn the bass off or the treble, it used active
filters. It was just coming out when I left.  

VG:  Around 1970 there were the Dymos and the Solos, which I believe
were solidstate.

CS: (Laughs) Yeah, that's true.  I'd forgotten about them.  Somewhere in
that time we started to use the Bridge T circuit on the tube amps.
There was a guy named Raul Longworth - friend of Tenyck's - and he was a
jazz guitarist.  We were sitting in the lab listening to him and some of
the complex chord structures - our original circuit kind of muddied up
and wasn't real clear.  But with this Bridge T circuit, it was much
clearer.

VG: Did you continue the artist's program into the '70s, after Buck
Munger left?

CS: A little, but not as much.  We'd had that extra office in L.A.,
which cost us a lot of money.  And I think we lost about $75,000 on
equipment for Jimi Hendrix, which he destroyed.

VG: Or gave away.

CS: I remember one day a big pile of trash came back, holes in the
grillecloth where a guitar neck had been shoved through.  It was kind of
a turnoff.  I'm a very conservative-type person, so I had trouble
relating to that whole scene.

VG: Did you meet many of the bands back then?

CS: Yeah, the Beach Boys, the Rolling Stones, Hendrix...I didn't really
get to know them, I had a good time talking to them, but was just kinda
there.  Some of the scenes in the dressing rooms and backstage were
pretty wild!  I was born in 1938 and was more interested in the music
being produced, some of Hendrix's stuff was really innovative, Iron
Butterfly was interesting, but that whole drug scene was a real
turnoff.  A lot of the ethics, morals - I felt we were kind of a
subcontractor to the drug industry, like we supported this culture.
Those kind of thoughts went through my head toward the end.

Postscript
Following a dispute with stockholders, Sundholm agreed to sell
controlling interest in Sunn to the Hartzell Corporation, a conglomerate
from Minnesota.  The deal was set up by an investor ca. '71.  Part of
the deal included a covenant not to compete, but after selling out his
share in the business, the founder of Sunn was free.
After his release from the Hartzell contract, Conrad formed Biamp with
Dick McCloud, the engineer responsible for the solidstate Sunn Coliseum
amps.  This company had a great deal of success in the sound
reinforcement field, building mixing boards, equalizers, amplifiers,
etc.
As with Sunn, Sundholm left the company after a falling out with
stockholders and went on to form Sundholm Electronics in 1982-'83.  His
namesake business again manufactured sound reinforcement equipment,
e.g., power amps, crossovers, and the industry's first single-rack
graphic equalizer.
When Sundholm Electronics folded, the former head honcho of three
influential musical equipment manufacturers did some consulting work for
Shure and Electro-Voice.  He had no intention of getting back into the
business, but recently joined with his youngest son, Steve, to form
Sundholm Acoustics.  It seems Steve looked around for monitor speakers
for his recording studio and felt his dad could top what was currently
available.  A test run of 100 pairs is underway and a product review in
Mix magazine is set an upcoming issue.  The Sundholms seem confident
their product has achieved its goals and they are expanding into custom
interconnects and microphone cables for high-end applications.  Contact
them at Sundholm Acoustics: fax 503-786-1550 or e-mail
love@teleport.com.

Special thanks this month to a number of people: Conrad Sundholm for the
interview, Ray Pirotta and his lovely wife Mary for the photo session,
Denny Loveridge and Peter Blecha/Experience Music Project for the photos
and my patient cohorts at VG.

..and Pt. III , from the February '99 (also available).

'60s Sunn Tube Amps

By John Teagle

Introduction
"If you can remember the '60s, you weren't there, man!" 
While many VG readers were indeed "there" when Sunn joined the musical
instrument amplifier market in the mid '60s, the early models are now a
third of a century old and can be legitimately classified as "vintage"
amplifiers.  Considering the number of guitar and bass heroes who used
them, and the fact they have not become technologically outdated, it's
strange there isn't more interest in at least the early versions.

Unfortunately for Sunn collectors, the amps were very expensive in their
day and were pretty much always taken out by professionals as working
amps, suffering the typical tortures of oversized gigging equipment.
Clean original examples are, therefore, hard to find - players weren't
buying these as practice amps!  Another strike against the amps as
vintage amplifier collectors items is they are mammoth and do not sit on
bookshelves.  But hey, people collect Marshalls and Bugattis!  Limited
info on details and specific models hasn't helped generate interest,
either.  And yet another reason that should be obvious is the amps were
especially favored by bass players, making the guitar amps rarer. 

The bass amps?  Well, you know bass players...they, uh, well...just
aren't as fanatical about collecting as...gulp...better change the
subject.

One of the few out there who really know these amps, fellow New Yorker
Ray Pirotta, was kind enough to provide a hands-on look at a number of
models from several eras, pulling out gem after gem from his 30 years of
continuous Sunn ownership.  All the amps pictured here are from his
collection.

And in case you missed it, the November '98 "Vintage Amplifiers" column
examined the Sunn amps relating to the Jimi Hendrix Experience, plus
Noel Redding on amplifiers - including his extended use of the 200S and
2000S models - and a firsthand account of the company's artist relations
program.  Former A&R man Buck Munger was also interviewed and recently
sent a great photocopy of Hendrix playing through a wall of Sunns.  It's
clear he was using 100S heads that day instead of the Coliseum PA heads
he is generally associated with.  We'll try to get the photo.
This month we'll feature all of the Sunn tube amps from the '60s and
discuss how to put an approximate date on them, as well as identifying
changes in features and designs.  For company history and firsthand
details on a variety of early versions, check out last month's interview
with company founder Conrad Sundholm.

Part I: Identifying Sunn Features

Dynakit Days
Brothers Conrad and Norm Sundholm started Sunn in 1965, although the
first prototype bottom may have been assembled a bit earlier.  The
original split-chassis amps were basically separate DynaKit HiFi preamps
and amplifiers mated to heavy-duty, state-of-the-art cabinets with JBL
15" D130 speakers.  Response to the amps, particularly by bass players,
led the duo to pursue the venture as a serious business.
A half-dozen heads were assembled using the 60-watt Dyna Mark III
amplifier and the PAS-1 preamp, which mounted to the top of the cabinet,
with controls facing the rear.  Sundholm reports, with a hint of
exaggeration, that it took six months to sell this first batch!  The
cabinets were bass-reflex types (ported) except for Norm's, which was
the first rear-loaded folded-horn type.  This cabinet became the bottom
of all bottoms for serious bass players. 

All these amps were fitted with "white" grillecloth (see last month's
Kingsmen photo).  The original black-on-gold logo plate with a
ray-radiating, happy-faced sun on the left side, "AMPS" running
vertically on the right and a slanted "SUNN" running horizontally across
the middle was there right from the start, implying these guys meant
business.  Guesstimates from the boss vary between 50 and 100 of these
logos being ordered, with their use continuing into the early production
models.

Standard Production
The first production models from the Sunn Amplifier Company were built
in Conrad Sundholm's home and were cosmetically similar to the
prototypes, with black covering, the smiling sun logo, and white
grille.  While features may have changed slightly in the early days, the
use of highest-quality components such as KT88 power tubes and JBL
speakers was consistent.  A second, less powerful head (40 watts from
twin EL34s) and a single 15" rear-loaded folded-horn joined the line for
the first promotional flyer from very early '65.  This flyer describes
the Dyna preamp with separate bass and treble controls for each of two
inputs (bass and guitar).  Vibrato and a mic preamp were listed as
standard equipment, however, the additions never made it to production.
A somewhat later price list, dated April 1965, also listed a few
cabinets with 12" speakers that were never actually built.  Sundholm
also notes that the reverb option never materialized, either.

Consistency in the use of black Tolex and a bluish/grey diagonal
grillecloth was established while the amplifier sections were still
separate from the preamps and would continue until the end of the '60s.
The control panel for the new preamps faced up through the top of the
cabinet at the rear, a la Fender tweeds and had the smiley-faced Sunn
logo stencilied on in black.  Bass and guitar versions were available.
The single 15" with horn 100S cabinet jointed the line and was
distinguished from the rest by a naugahyde stripe down the left side of
the grille on the speaker cabinet.  These were made in Sundholm's
father's shop.  The Rolling Stones reportedly used this era of Sunns for
their concert at the Seattle Center (anybody know the date?) and were
photographed in the dressing room with a nice selection of them.
Around this time, things started to pick up for the young company.  A
new logo with silver letters and concentric circles of solar radiation
on a black background would become the company's standard trademark.
These were applied to the last of the split-chassis amps, of which
approximately 200 total were reportedly made.  A photo of these
transition models was printed in the December '98 VG (page 113).

Having come up with another new circuit (still based on the Dyna line),
the company began mounting both preamp and amplifier components on a
single chassis.  This style was introduced by early '66, with an
aluminum control panel exposed along the entire bottom/front of the box,
allowing easy access to the controls.  Numbers were stencilled onto the
control panel and knobs with a simple white arrow and chrome top became
standard issue, lasting into '67.  Nationwide distribution was
established through trade shows and word of mouth, bringing the small
line to the Midwest and east coast, as well as the northwest and other
points that side of the Mississippi.  Models included the 100S, 200S,
Spectrum I, Spectrum II, Sonic I, and Sonic II (anybody have something
else with numbered control panels?).

The catalog for '67 unveiled a greatly expanded lineup from the earliest
offerings.  The company was well on its way at this point, having moved
into its new factory in nearby Tualitin.  Available were two midsized
all-purpose amps, three smaller bass amps, three guitar amps with reverb
and tremolo, plus two PA systems in addition to the original high-end
guitar amp/bass amp lineup.  It's difficult to tell from the pictures
whether the numbers are on the control panels or the knobs, but on
certain pictures it's clear numbered knobs were being introduced and
some models were still being presented with numbered panels.  The
lettering on the nameplate varied in thickness but was generally thinner
around this period and the registered trademark symbol following "Sunn"
was not yet instituted.  Little if anything else changed cosmetically,
and the use of high-end components and JBLs as standard equipment
continued.

Big changes in Sunn's status occurred before the release of the next
catalog in '68.  A list of endorsers on the back cover included names
like the Jefferson Airplane, Jimi Hendrix Experience, Cream, the Who,
the Grateful Dead, the Buckinghams, Righteous Brothers, Blues Magoos,
Steppenwolf, Fever Tree, and Genesis, plus Sunn's travelling goodwill
ambassadors, Houston Fearless.  Big news was the addition of the
powerful 1000 series guitar amps and their bass counterpart, the 2000S.
These are easily identified from standard models by oversized bottoms
and the black rectangle with silver letters screened on the head's
control panel, matching the logo plate instead of the usual black or red
letters on silver complement.

The last noticeable change to the blue diagonal-grilled models came with
the addition of the registered trademark insignia in the bottom corner
of the word "SUNN" on the logo plate.  This change appears to have
occurred around late '68/early '69.  The dimensions of these nameplates
differ, so check for extra holes in the grille when purchasing
"pre-trademark" models.

Sunn entered the '70s with a sparkly new grillecloth on all models,
similar to the cloth used by Fender, with a pronounced rectangular
pattern.  This pattern runs vertically on the Sunns, compared to
Fender's horizontal layout, and like the silver sparkle grille on
blackface Fenders, the cloth seems to take on a brown tint, even on
really clean examples.  The earlier blue diagonal cloth takes on a less
drastic brown tint with years of nicotine exposure and has a much
smaller pattern.  Pirotta recalls the change in grilles occurring in
late '69; seems he ordered a 2000S bottom and when it arrived in
November, surprise! - it didn't match anything.  Thus it seems safe to
say some Fender-style grilled Sunns are from '69, but most are from the
early '70s.

Part II: '60s Guitar Amps

Sunn Amp
1965 - The first production amplifier by the new company was simply
called the Sunn Amp.  This model was offered to both guitarists and bass
players, with inputs and separate bass and treble controls for each,
plus a third input with a separate circuit for a microphone.  This
preamp was available with the twin KT88, 60-watt Mark III amplifier or
the twin-EL34, 40-watt Mark IV.  

100S
1965-'66 - When Sunn went from using PAS-1 preamps to its own circuit
(still split-chassis), separate models were designed for bass and
guitar.  Showing the influence of hi-fi mentality and JBL engineers, the
42" X 24" X 15" folded-horn bottom featured a 15" D130 and an LE100S
midrange driver with acoustic lens/horn.  The use of horns in guitar
amps was popular in the late '60s, at least among competing
manufacturers.  The public response was less than enthusiastic.  A
naugahyde stripe ran down the front of the speaker cabinet on these
early examples.

1966 - Introduced the new front control panel/single chassis, featuring
a pair of KT88s and Dynaco transformers.  The four knobbed, 60 watt head
featured Volume, Treble, Bass and Contour controls, two inputs and the
trio of rocker switches on the far right side for Power, Standby and
Polarity.  These switches and the layout of the panel became standard
for all the Sunn amps.  A GZ34 rectifier, 7025 preamp and 6AN8 phase
inverter were standard for the 60-watters.

Late '67 - Four-knob head replaced by seven-knob Sentura II effects
version of the 60-watter.  Same bottom with horn offered in '68 catalog,
though the last of these were reportedly sold with the big 2 X 15"
folded horn and two D130s before being phased out by the '70 catalog.
KT88s were replaced with 6550s on all the amps by early '69.

Spectrum II
1966 - Essentially an early 100S head with a smaller 38" X 24" X 111/2"
bottom containing two D130s mounted catty-cornered on the bass reflex
baffleboard.  Designed as a mid-priced all-around amp with less low-end
than the 200S.
1968 - Larger folded-horn cabinet 42" X 24" X 15" with two D15S guitar
speakers.  6550s by early '69.

Spectrum I
1965 - Same preamp and controls as 60-watt split-chassis, but with less
power from twin EL34s putting out 40 watts.  Referred to in flyer as
Sunn Amp but obvious predecessor of the Spectrum I when the four-knob
preamp with Contour replaced the PAS-1.
 1966 - Single-chassis direct descendent of the low-powered
split-chassis Sunn Amp.  Lower-priced all-around amp with the four
controls of the 100S but a smaller output amplifier section.  A pair of
EL34s, a 5AR4 rectifier, 7025 preamp and 7199 phase inverter were
standard for the 40 watt amps.  The 38" X 24" X 111/2" bottom utilized a
D130 in a bass reflex design.  Discontinued by '68 catalog.

Sentura II
1967 - Sunn's entry into a modern guitar amp with solidstate reverb and
tremolo sections.  This seven-knob amp used the same tubes as the other
60-watt heads, with the addition of a 12AU7 in the reverb driver stage.
Four inputs allowed the amp to share chassis with the PA systems.  The
bottom was the same as the Spectrum II.
1968 - Larger folded horn cabinet 42" X 24" X 15" with two D15S guitar
speakers.  6550s by early '69. 

Sentura I
1967 - Seven-knob effects head with the smaller EL34 power section plus
a 12AU7 reverb driver.  Mated with a Spectrum I bottom.
1968 - D15S replaces D130.
1969 - Upgraded to 60 watts with two 6550s.

Solarus
1967 - Basically a 40-watt Sentura I head in a combo amp with two 12"
Sunn speakers.  The first Sunn without a JBL.  The cabinet matched the
Sentura I in size, but was notched back at the top to recess the
controls.
1969 - Upgraded to 60 watts with two 6550s and piggyback construction.

Sceptre
1968 - In response to the English infinite-baffle (sealed) 4 X 12"
bottoms, Sunn offered the popular speaker configuration in a large
200S-sized cabinet (examination of the interior shows routs for missing
folded-horn construction).  The speakers were staggered, with the left
side lower than the right.  The head was a 60-watt effects model as used
for the Sentura II and new 100S.  6550s by early '69. 

1000S
1968 - Taking the 100S another step by doubling the power and 15" JBLs,
the 1000S was Sunns most expensive guitar amp.  Part of a new series
based on the Coliseum PA, the amplifier combined the seven-knob effects
circuit with four KT88s and twin GZ34 rectifiers.  The cabinets for the
powerful heads measured 10" X 30" X 91/2" instead of the 91/2" X 24" X
91/2" used on all the twin-power-tube heads.  The 48" X 30" X 15"
rear-loaded folded-horn bottoms (it was pictured with two) each held a
pair of D15S 15" guitar speakers plus an LE100S high-frequency driver
and horn.  These cabinets were overkill for guitars and were replaced by
the twin 15" D15S cabinets of the discontinued 1500S in '69.  Like all
Sunn amps, the 1000 series changed from KT88s to 6550s by early '69.

1200S
1968 - Like the smaller Sceptre, the 1200S employed 12" speakers, using
six per 1000S-sized cabinet.  Unlike the British cabinets, the 6 X 12"
had a tuned-port design, but the head was straightforward, without
effects (an oversized Spectrum II with four inputs).  Later models used
the seven-knob effects head of the 1000S with four 6550s.

1500S
1968 - The short-lived 1500S included the effect-less head of the 1200S
and a pair of twin D15S speaker cabinets.  The model was discontinued
when its 2 X 15" bottoms replaced the two-way system of the 1000S in
'69.

Part III: '60s Bass Amps

"Sunn Amp"
1965 - While there wasn't a separate amp for bass in the original line,
the original Sunn Amp (see above) could be used for either guitar or
bass.  Second split-chassis version preceded the 200S.

200S
1966 - Single-chassis version 60-watt head for bass with volume, treble
and bass controls, plus hi-boost and low-boost switches.  Two D140s were
placed in separate folded horn sections of the 42" X 24" X 15" bottom
(same size as 100S).  This was one of the company's most enduring
designs, revered to this day by bass players of the era.  A true classic
in bass amp history!
1969 - Change to 6550s.

Sonic II
1966 - A short lived model that was essentially a 200S with D130s.  The
large folded horn cabinet and three knob/two switch 60-watt head appear
to be identical to the 200S.  Discontinued by '68 catalog.

Sonic I
1965 - Like the 60-watt Sunn Amp, could be used for bass and was the
inspiration for the 200S, the 40-watt Sunn Amp would be the logical
predecessor of the 40-watt bass amp with a single 15" rear-loaded
folded-horn bottom. 
1966 - Updated to the three-knob, two-switch front control panel and
became known as the Sonic I.  Discontinued by '68 catalog.

Sonic I-40
1967 - Half of a 200S bottom coupled to a three-knob, two-switch 40-watt
head.  These are great bottoms, with the rear-loaded folded-horn D140
frequency response but not as cumbersome as the 2 X 15" model.
Otherwise, identical to Sonic I.
1969 - 60 watts from two 6550s.

Sonaro
1967 - Combo bass amp with the 40-watt Sonic I head and a 15" Sunn
speaker.  Same size as the Solarus.
1969 - 60 watts from two 6550s.

Sorado
1968 - Like the Sonic II it replaced, the three-knob/two-switch 60-watt
Sorado was essentially a 200S with cheaper speakers, this time
heavy-duty 15" Sunns.  6550s by early '69. 

2000S
1968 - If there's one amp that represents Sunn's best qualities, it's
the 2000S.  Just about everyone agrees Sunn made good-to-great-sounding
bass rigs, and this was their piece de resistance.  There's the bottoms
- twin D140s in an oversized rear-loaded, folded-horn cabinet measuring
a whopping 48" X 30" X 15".  Place two of these side-by-side and you can
put out a match with a thump on the E string (or so legend has it).
These cabinets are efficient and get loud at all frequencies, something
many of the smaller miracle cabs can't.  Couple that with four KT88s and
a simple set of controls with a bass boost switch and you're ready for
just about anything (see October '98 VG for more on the 2000S).

Part IV: '60s PA Systems

Beach Boys Model
1966 - At the request of surf vocal group (not surf band!) the Beach
Boys, Sunn entered into what would become a major part of its business
in later years - public address systems.  The system sold to the group
differed from production models in that it contained a passive
Switchcraft four-channel microphone mixer.  This was coupled to a
standard 60-watt head to push two state-of-the-art three-way speaker
systems, each with two 15" D140s, a 375 compression driver with acoustic
lens/horn in a separate cabinet and an 075 bullet tweeter protruding
through the baffleboard of the 2 X 15" cabinet.

Studio
1967 - Sunn followed up on the Beach Boys PA with a similarly powered
twin-KT88 head and a smaller set of two-way speakers featuring a JBL
130AS 15" and the LE100S driver/horn used on the 100S guitar amp.
Dimensions for the cabinets were 29" X 24" X 111/2", allowing them to be
suspended on stands.  The Studio PA head had seven knobs and four inputs
laid out like the guitar heads with effects; however, the knobs were
four volumes, treble, bass and master volume.   Tubes were similar to
the standard 60-watt head with the addition of two extra 7025s for the
individual mic preamps.  Replaced with solidstate Concert Sound System
by 1970 catalog.  

Coliseum
1967 - As the name implies, the Coliseum topped everything in size and
power.  Taking the speakers from the Beach Boys system and adding a head
with twice the power allowed the Coliseum to gobble up Vocal Masters and
anything else that dared challenge it.  The only drawback was the price;
it seems the four-KT88 circuit predated any of the English 200-watt
heads, although Sunn only claimed 120 watts RMS from its version.
Enormous transformers were needed, as well as a beefed up power supply
with dual rectifiers.  The controls were the same as the Studio.  6550s
by early '69. 

Postscript
When these amps were new, players had a great deal of respect for the
Sunn name, and they forked over piles of cash to acquire them.  Somehow,
by the end of the '70s the brand's reputation had dropped a notch and
used models became laughably affordable or impossible to get a fair
price out of, depending on which side of the stack of bills you were.
Perhaps because they seemed so closely associated with the late-'60s
music scene or because of the company's change in ownership and switch
to solidstate in the '70s, Sunn amps have not been considered "cool" for
years.  But if you look back at the early models and the part they
played in a very important era of rock and roll history, it's apparent
these top-quality products don't belong with the Traynor, Univox, Sound
City, Plush, grey/black Gibson, silverface Fender, and solidstate
miscellany, etc. they've sat with for the last 20 years on pawnshop
floors or in music store basements.  Sixties Sunn amplifiers deserve to
again sit at the table with Marshall/HiWatt/Orange, Fender, Ampeg, Vox,
et. al.; amps that in Sunn's heyday were merely the competition.
Special thanks to Ray Pirotta for his monumental effort, and to Conrad
Sundholm for answering lots of questions and digging up the early flyer.

VINTAGE AMPLIFIERS

SIXTIES SUNN TUBE AMPS

By John Teagle

INTRODUCTION
While many VG readers still remember Sunn joining the musical instrument amplifier market in the mid '60s, the early models are now over thirty years old and can be legitimately classified as "vintage" models. Considering the number of guitar and bass heroes who used them, and the fact they have not become technologically outdated, it seems there should be more interest in these.  Not that there aren't people out there who take these powerhouses seriously.

Unfortunately for Sunn collectors, the amps were very expensive in their day and were pretty much always taken out by professionals as working amps, suffering the tortures oversized gigging equipment regularly gets put through.  Clean original examples are therefore hard to find - players weren't buying these as practice amps!  Another strike against the amps as vintage amplifier collectors items is they are mammoth and do not sit on bookshelves, but hey, people collect Marshalls and Bugattis...  The fact that very little info is readily available to the public on details and specific models hasn't helped generate interest, either.

Of the few out there who really know these amps, fellow New Yorker Ray Pirotta was close enough and kind enough to provide a hands on look at a number of different models from a number of eras, pulling out gem after gem from his thirty years of continuous Sunn ownership.  All the amps pictured here are from his collection.
In case you missed it, the October '98 Vintage Amplifiers column examined the Sunn amps relating to the Jimi Hendrix Experience, plus Noel Redding on amplifiers including his extended use of the 200S and 2000S models plus a firsthand account of the company's Artist Relations program.  This month we'll take a look at all the Sunn tube amplifiers from the '60s and how to put an approximate date on them, as well as identifying changes in features and designs.  For company history and details on a variety of early versions, check out the accompanying Conrad Sundholm interview.

PART I: IDENTIFYING SUNN FEATURES

DYNAKIT DAYS
Brothers Conrad and Norm Sundholm started Sunn in 1965, although prototypes were being assembled at least a year earlier.  The original split chassis models were basically separate DynaKit HiFi amplifiers and preamps with heavy duty, state of the art cabinets.  Response to the amps, in particular the bass model, led the duo to pursue the venture as a serious business. The first production models, though limited in number, featured a black on gold logo with a smiling sun.  While features such as covering, grille cloth and controls were changing regularly, the use of highest quality components such as KT88 power tubes and JBL speakers was consistent. 

STANDARD PRODUCTION
Consistency in the use of black Tolex, blue sparkle grille cloth and a new "silver letters and radiating sun on black background" logo was established while the amplifier sections were still separate from the preamps, as on the earliest models.  The control panel for the preamp faced up through the top of the cabinet at the rear, ala Fender tweeds.  By early '66, an aluminum control panel exposed at the bottom-front of the box was standard, allowing easy access to the controls.  Numbers were stencilled onto the control panel, allowing the use of knobs with a simple white arrow and a chrome top which would be standard into 1967. Nationwide distribution was being established through trade shows and word of mouth, bringing the small line to the midwest and east coast, as well as the northwest and other points that side of the Mississippi.  Models included first, the 100S and 200S, then the Spectrum I and II plus the Sonic I and II.  (Anybody have something else with numbered control panels?)

The catalog for '67 unveiled a greatly expanded lineup from the earliest offerings.  The company was well on its way at this point, with two mid-sized all purpose amps, three smaller bass amps, three guitar amps with Reverb and Tremolo plus two P.A. systems, in addition to the original high-end guitar amp, bass amp lineup.  It's difficult to tell from the individual pictures whether the numbers are on the control panels or the knobs, but on certain pictures it's clear that numbered knobs were being introduced and some models were still being presented with numbered panels (photos of older models?). The lettering on the name plate varied in thickness but was generally thinner around this period and the registered trademark symbol following "Sunn" was not yet instituted.  Little, if anything else changed cosmetically.

Big changes in Sunn's status occurred before the release of the next catalog in '68.  A list of endorsers on the back cover included names like the Jefferson Airplane, Jimi Hendrix Experience, Cream, the Who, theGrateful Dead, the Buckinghams, Righteous Brothers, Blues Magoos, Steppenwolf, Fever Tree and Genesis???, plus Sunn's travelling goodwill ambassadors, Houston Fearless.  Big news was the addition of the powerful 1000 series guitar amps and their bass counterpart, the 2000S.  These are easily identified from standard models by the black rectangle with silver letters screened on the control panel, matching the logo plate instead of the usual black letters on silver complement.

The last noticeable change to the blue grilled models came with the addition of the registered trademark insignia in the bottom corner of the word SUNN on the logo plate.  This change appears to have occurred around late '68-early '69.  The dimensions of these nameplates differ, so check for extra holes in the grille when purchasing "pre-trademark" models.

Sunn entered the '70s with a new wheat colored sparkly grille cloth on all the models, similar to the cloth used by Fender with a pronounced rectangular pattern.  This pattern runs vertically on the Sunns, as compared to Fender's horizontal layout.  The earlier blue cloth, which can take on an almost brown tint with years of nicotine exposure, had a much smaller pattern that runs in diagonal rows.  Mr. Pirotta recalls the change from blue to wheat occuring in late '69; seems he ordered a 2000S bottom and when it finally arrived in November and was pulled out of the box, SURPRISE!!  - it didn't match anything.  Knowing that, it seems safe to say that some wheat grille Sunns are from '69, but that most are from the early '70s.



Here's a simple chart to help establish a lineage for approximately identifying various years.  While the dates may run into preceding and following years, the general order of events appears to be consistent.  Also check out the info on different models that follows.  (Note: Response giving details of existing amps or original owner info is always appreciated, whether it corresponds and reinforces what's been printed or it contradicts.  Updates will be made in the second annual Vintage Amplifiers round-up column.)

1965  Black on gold logo with face on earliest production, some with red nose.
2.) Split Chassis with top mounted control panel as seen on all early amps.
 Later examples with standard appointments, i.e., black Tolex, blue grille cloth, new logo/nameplate.
1966-7          Front control panel, numbers on panel, plain knobs w/arrow
1967-8          Numbers on knobs, no trademark symbol on logo plate
1969            Registered trademark on SUNN logo plate
Late 1969 -     Wheat colored Fender-style grille cloth replaces blue





PART II: '60s GUITAR AMPS
100S
1966  This model came out of the early trials and was the first standard model guitar amp for the new company.  Showing the influence of HiFi mentality and JBL engineers, the 42"x24"x15" folded horn bottom featured a 15" D130 and an LE100S midrange driver with acoustic lens/horn. The use of horns in guitar amps was popular in the late '60s, at least among competing manufacturers.  The public response was less than enthusiastic.

Featuring a pair of KT88s and Dynaco transformers, the four knobbed 60 watt head featured Volume, Treble, Bass and Contour controls, two inputs and the trio of rocker switches on the far right side for Power, Standby and Polarity.  These switches were standard on all the Sunn amps.  A GZ34 rectifier, 7025 preamp and 6AN8 phase inverter were standard for the 60
watters.

Late '67  Four knob head replaced by seven knob Sentura II effects version of the 60 watter.  Same bottom with horn offered in '68 catalog, although the last of these were reportedly sold with the big 2-15" folded horn and two D130s before being phased out by the 1970 catalog.  KT88s were replaced with 6550s on all the amps by early '69. 

SPECTRUM II
1966  Essentially an early 100S head with a smaller 38"x24"x11 1/2" bottom containing two D130s mounted catty-cornered on the baffle board.  Designed as a mid-priced all around amp with less low end than the 100S and 200S. Probably a bass reflex cabinet.

1968  Larger folded horn cabinet 42"x24"x15" with two D15S guitar speakers.  6550s by early '69.

SPECTRUM I
1966  Lower priced all around amp with the controls of the 100S but a smaller output amplifier section utilizing a pair of EL34s.  A 5AR4 rectifier, 7025 preamp and 7199 phase inverter was standard for the 40 watt amps.  The 38"x24"x11 1/2" bottom utilized a D130 in a bass reflex design. Discontinued by '68 catalog.

SENTURA II
1967  Sunn's entry into a real guitar amp with solid state Reverb and Tremolo sections.  This seven knob amp used the same tubes as the other 60 watt heads, with the addition of a 12AU7 in the reverb driver stage.  Four inputs allowed the amp to share chassis with the P.A. systems.  The bottom was the same as the Spectrum II.

968  Larger folded horn cabinet 42"x24"x15" with two D15S guitar speakers.  6550s by early '69.  

SENTURA I
1967  Seven knob effects head with the smaller EL34 power amplifier plus a 12AU7 reverb driver.  Mated with a Spectrum I bottom.

1968 D15S replaces D130.

1969 Upgraded to 60 watts with two 6550s.

SOLARUS
1967  Basically a 40 watt Sentura I head in a combo amp with two 12" Sunn speakers.  The first Sunn without a JBL.  The cabinet matched the Sentura I in size, but was notched back at the top to recess the controls. 

1969  Upgraded to 60 watts with two 6550s and piggyback construction.

SCEPTRE
1968  In response to the English infinite baffle (sealed) 4-12" bottoms, Sunn offered the popular speaker configuration in a large 200S sized cabinet (examination of the interior shows routs for missing folded horn construction).  The speakers were staggered, with the left side lower than the right.  The head was a 60 watt effects model as used for the Sentura II
and new 100S.  6550s by early '69.  

1000S
1968  Taking the 100S another step further by doubling the power and the 15" JBLs, the 1000S was Sunns most expensive guitar amp.  Part of a new series based on the Coliseum P.A., the amplifier combined the seven knob effects circuit with four KT88s and twin GZ34 rectifiers.  The cabinets for the powerful heads measured 10"X30"x9 1/2" instead of the 9 1/2"x24"x9 1/2" used on all the twin power tube heads.  The 48"x30"x15" rear loaded folded horn bottoms (it was pictured with two) each held a pair of D15S 15" guitar speakers plus an LE100S high frequency driver and horn.  These cabinets were overkill for guitars and were replaced by the twin 15" D15S cabinets of the discontinued 1500S.  Like all the Sunn amps, the 1000 series changed from KT88s to 6550s by early '69.

1200S
1968  Like the smaller Sceptre, the 1200S employed 12"  speakers, using six per 1000S sized cabinet.  Unlike the British cabinets, the 6-12" had a tuned port design, but the head was straight forward, without any effects, like an oversized Spectrum II with four inputs.  Later models used the seven knob effects head of the 1000S with four 6550s.

1500S
1968  The shortlived 1500S included the effect-less head of the 1200S and a pair of twin D15S speaker cabinets.  The model was discontinued when its 2-15" bottoms replaced the two way system of the 1000S.


PART III: '60s BASS AMPS

200S
1966  Similar 60 watt head to the 100S, but for bass with Volume, Treble and Bass controls, plus Hi-Boost and Low-Boost switches.  Two D140s were placed in separate folded horn sections of the 42"x24"x15" bottom (same size as 100S).

1969  Change to 6550s

SONIC II
1967  A short lived model that was essentially a 200S with D130s.  The large folded horn cabinet and three knob/two switch 60 watt head appear to be identical to the 200S.  Discontinued by '68 catalog

SONIC I-40
1967  Half of a 200S bottom coupled to a three knob/two switch 40 watt head.  These are great bottoms, with the rear loaded folded horn D140 frequency response but not as cumbersome as the 2x15" model.  

1969  60 watts from two 6550s.

SONIC I
1967  Shortlived model identical to Sonic I-40 except for a D130 and slightly lower price.  Discontinued by '68 catalog

SONARO
1967  Combo bass amp with the 40 watt Sonic I head and a 15" Sunn speaker. 
Same size as the Solarus.