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The Sunn Rises

The Sunn Shack

My Sincere and Heartfelt Thanks to Conrad and Norman Sundholm and to all those who have been responsible for carrying on the SUNN legacy.

Please, READ THIS FIRST!!!!!! Greetings Ladies and Gents,

You’re about to wander helplessly into an extremely passionate area of my life. HOWEVER, I am not a Techie. I don’t know anything about tubes, wiring, whiffle-dust on the transformer’s muffler bearings and/or how it affects the tone of the amp, etc. I simply know that I love SUNN amplifiers. For answers to your tech questions, or simply to “come out of the SUNN Closet” and find comfort and solace knowing that others “feel our pain”, please go the Un-official SUNN Site

Here are some other cool places to visit

E-MAIL!! This one’s a biggie: I work a 15 hour day, every day, here in a Northeast section of the U.S. As part of my job I receive anywhere from 25 to 75 Emails a day, sometimes more; E-mails that MUST be answered. See where this is going? I have a stack (several hundred) of SUNN Emails that are expecting, hoping for, and deserve responses. Much to my regret, however, unless someone finds a way to add MANY more hours to the day, I’m totally unable to answer them. My sincere apologies to those of you who’ve written.

Therefore, if you like this site, hate this site or just want to make comments to me privately, I do read every one that you send along. However, many other Sultans of SUNN all over the world would love to hear from you too, so I’d ask that you post ANY and ALL of your SUNN thoughts and memories on the message board at the site, so that all of us may enjoy them. After all, we’re a bunch of sicko’s…and just knowing that others with the same addiction/affliction actually exist seems to give us all a degree of comfort

Bass-ically Yours,


SUNN Schematic of the Month! Here’s the “thumbnail” (click on it) schematic for the Sunn Coliseum Bass @ 1975/6/7/8

Who, What, WHY?

Anyone stopping here who doesn’t know about SUNN amplifiers will probably wonder why on Earth I would find them appealing enough to put up this page. Just know this: Sunn bass amps are, indeed, the Holy Grail for me—they always have been. The late 60’s models are the Cat’s Meow and I still use an original SUNN 200S for recording. The NEW MODELS from SUNN are absolutely Tone-Monsters. I use a SUNN 300T with a 2×15 and a 4×10 for live performances and my stage rig is a personal dream come true. Once you’ve used one it’s very difficult to go back to anything else.

You’ll notice that we have a couple of guests who contribute to this site. It’s a real honor for me to have Conrad Sundholm adding bits of history to this page and you can find a lot more discussion on SUNN products at: The “Un-Official”


SUNN Amplifiers The amplifier that spawned the explosion of power line-ups throughout the ‘60’s and ‘70’s. The amplifier used by Jimi Hendrix and Noel Redding, by Pete Townsend and John Entwistle, by Tony Iommi and Geezer Butler, by Geddy Lee, by Brian May, by…starting to get the picture?

With truly power mad guitarists such as these, the name SUNN had quickly established its musical foothold, becoming synonymous with the blood curdling, bone crunching, rock-and-roll that would infect an entire generation. And all of this can be attributed to the one band who’s music will forever be remembered in rock history: The Kingsmen.

The Kingsmen? That’s right! The band who brought you the party anthem “Louie Louie”, and quickly faded into anonymity, also brought the amplifier that paved the way for so many that would follow.

“SUNN’s legacy reads like the history of rock,” explains Richard McDonald, Marketing Manager of SUNN Amps. “To paint a little picture, just take a look at the inside cover of your Woodstock album, and you’ll get an idea of the magnitude that SUNN amplifiers had in revolutionizing early rock music.”

Jump back a couple of years. The concert scene of the late ‘50’s and early ‘60’s was dominated by groups touring together. It was very common to have four or five bands, sometimes more, sharing a bus and playing on the same bill. And remember, “arena rock” was not yet a term. Most venues at the time were either theaters or small clubs, and portable amplifiers seemed to do the trick. For a while at least.

Obviously, rock music enjoyed a growing popularity. With that, venues were getting bigger to accommodate the larger numbers of people that were going to concerts. Still though, bands would plug in the same amplifiers that they were using at the smaller venues. Why? Because that’s all there was at the time.

Enter the Kingsmen. Norm Sundholm, bass player for the band, frequently complained that his bass amp was getting lost in the noise from other the other members’ amps and from the audience. So he called up his brother Conrad, an electronics enthusiast, and asked if he could rig something up that might help him out.

"Things weren’t real scientific back then, not like today with computers,” explains Conrad. “So I built this cabinet I had, which became the 2-30/C60…that first one was a real beast.” That “beast” that Conrad had come up with was a bass amp that would set the music world on its ears.

Other musicians soon heard the Sundholm brother’s amplifiers, and were absolutely in awe with their power. Norm and Conrad started to receive orders from guitarists and bass players who had to have one just like it. So Conrad set up shop in his dad’s garage, started building what would become SUNN amplifiers, and turned a small project for his brother into rock-and-roll legend. The SUNN had risen!

Unfortunately for Sunn Amps, it was soon to set. Although the Brothers Sundholm had enjoyed a great deal of success, receiving endorsements from the Rolling Stones, The Who and Jimi Hendrix, they had quite different views on running the business. At the end of the ’60’s, Norm sold his interest in Sunn to Conrad and went on to pursue a career in real estate.”….

Then in 1971, Conrad sold the rest of SUNN to the Hartzell Corporation, a Minnesota based conglomerate.Hartzell continued to make SUNN amps throughout the ‘70’s and into the early ‘80’s, until a tragic plane crash took the life of its President, Tom Hartzell. His surviving family did little with SUNN amplifiers, and decided to sell it a few years later.

Enter the next player in the saga, Fender Musical Instruments. Having recently purchased Fender from corporate giant CBS, Bill Schultz (Fender Chairman & CEO) had seen the opportunity to re-build SUNN into the powerful company it had once been. However, Fender still had to tackle the job of re-building itself in the wake of CBS, and put SUNN on the shelf until the timing was more suitable.

Now jump forward a few years. With Fender back and better than ever, the timing seemed right to bring in their world-class Research & Development team of engineers to resurrect SUNN from the ashes. And resurrect it they did!

The SUNN Model T was redesigned as an all-tube, tonal assault machine. For unrelenting tone and muscle, match it with the SUNN Model T 412 enclosure and get ready to rock. For bassists, the new SUNN 1200S delivers the power and presence to handle any situation. With a supporting line-up of bass and guitar heads and enclosures, SUNN amps are blazing an all new trail into rock-and-roll history.

SUNN has risen again

What is it, exactly, that made me such a fan of SUNN?

Many things actually—-Tone is #1 on the list. I know that a large portion of the charm also comes from the fact that ALL of my heroes during the mid-60’s and thru the mid-70’s were each using SUNN. I wanted to join them at that time—but I couldn’t afford a SUNN so I had to make-due with others.

The 200S bass amp and accompanying JBL loaded 2×15 cabinet was, indeed, revolutionary in its time and still stands up tonally to the best offerings that current day bass amp manufacturers have to offer. As you can see from the front cover of the NEW SUNN catalog, many of our Rock & Roll Icons cut their musical teeth on SUNN gear. Eric Clapton, Jimi Hendrix and Pete Townsend were just three of the name GUITARISTS who used SUNN. As far as Bass Players go—SUNN ruled the world.

Every bassist worth his salt was sporting aSUNN rig—-on stage and in the studio.

Here are a few words from Conrad Sundholm one of the founders of the legendary SUNN Company and the designer of the SUNN 200S Bass cabinet. You can ask Conrad questions as well as take part in a pretty nifty discussion group by clicking here The following is an excerpt from that site.

Posted by Conrad Sundholm on September 19, 1999 at 00:13:02:

My brother Norm was working at a music store in Portland, OR and making mods to Fender sealed cabinets by porting them and selling them with 60 Bogen PA amplifiers. I helped him with the port size and tuning.

The very first cabinets under the Sunn name were dual 15″ JBL D130’s mounted in a 24 wide cabinet with the 15’s staggered with two ports next to the staggered 15’s. I borrowed $1300 from the Portland Teachers Credit Union (I was teaching at Centennial High School at the time) to purchase plywood, vinyl and JBL speakers. I swung a deal with a local dealer to purchase 12 JBL D130’s at below retail. The rep for JBL canceled him as a JBL dealer because he violated JBL’s “fair trade” agreement then immediately looked us up and wanted to set us up as an OEM account purchasing direct from JBL. I thought that was pretty hilarious at the time, but felt bad for the retailer who was trying to help us out. I didn’t find out about it for a year or so.

Anyway, it took me six months to sell those first 6 cabinets. Then I had a dream about how to build a bass cabinet. The dream was so vivid I got up the next morning and started building the cabinet. It was a rear loading bass reflex design which became the 200S bass cabinet. This particular unit contained extra bracing which was not included in the eventual production version. I then built a piggyback head enclosure and stuffed it with a Dynaco Mark II 6o watt tube kit I built along with a Dynaco tube preamp. This was Norm’s first unit he used on the road with the Kingsmen.

It had so much low end! Almost too much. The electronic response curves were for HiFi not bass guitars but it out performed anything on the market. As Norm traveled across the country playing this monster, everyone was asking him were he got this amp. He told them to ask their local music dealer to call me and order one for them. I started getting calls from Jacksonville, FL; Boston, MA etc. – These dealers were ordering 12 at a time – the rest is history.

The original dream became the well respected 200S cabinet. We later built our own preamp mounted in the top rear of the piggyback cabinet along with the Dynaco Mark III. Later we built it all on one chassis.

I have no idea where that very first cabinet wound up. I heard that Fender might have it. It has an extra row of screws on the back of the cabinet near the ends. This is where the extra corner braces were located. It was covered with a soft expanded vinyl which got torn quite easily but the box was rock solid.

Sunn was first located on the corner of Quarry Rd. and Upper Boones Ferry Rd. (now Carmen Dr.). This was my Father’s home. He had a warehouse- shop in the back that we used. When we ran out of space we made a lease deal with a Bill Amburn who owned a private recreational swimming pool business in Tualatin. He wanted out of that business and we needed a building. He punched a hole in the wall, filled the pool with sand and poured a floor and we had our cabinet shop. Electronics assembly was in the office area up front. This building was located Just west of Boones Ferry Rd. on the south side of the Tualatin Sherwood Hwy. It later became a auto body shop. Hope this helps Conrad Sundholm

In Reply to: Sunn 1960s “Folded Horn” Cab Specs??? posted by Karl on September 05, 1999 at 12:27:24:

This design came to me in the twilight of my sleep. I don not have any drawings of the cabinet, but I do have a memory of its construction. The cabinet’s external dimensions are 24″ wide, 36″ tall and 15″ deep. A 1/2″ plywood liner was placed on the inside front edge of the cabinet to make it look “beefy”. The port in the 2 X 15″ cabinet was 5″ high and ran the entire width of the cabinet. The horn baffle was formed out of two pieces of 1/2″ plywood. The horizontal piece being about 3 to 3-1/2″ in depth and the 45 degree angle piece being 9″ long. On the dual 15″ cabinet there were two baffle assemblies. The 1/2″ plywood horn baffle pieces were glued into routed grooves in the sides of the cabinet. The single 15″ was simply 1/2 of the dual 15″ cabinet with the port at the bottom of the cabinet with a single horn baffle assembly. I could sketch it for you but no draw capabilities on this e-mail response mechanism. I would be more than happy to send you a sketch.

Conrad Sundholm………See what Conrad is doing now by clicking on this link!

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…………$34.95For All Your Guitar Needs !

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

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!

The 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.


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

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

“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.


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.


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.


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.


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.


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.


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