Cool Stuff!

We take a lot of pictures here. Most are for reference - others are for LOLs! This page is dedicated to instruments I believe are worth posting. Thanks to all who have contributed!

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Keyboard: Circuit-bent Yamaha PSS-80

Owner: C. Marshall

The owner of this little keyboard wanted us to attempt to "circuit-bend" it. I thought I would give it a go - seemed like something fun to do! I have personally messed around with a lot of toys and consumer goods and have actually ruined some of them by attempting to apply amateur pseudo-tech thinking to make units operate way out of spec. That was difficult to achieve considering I am a repair technician and to blindly place a wire from this point to that point without understanding what could happen in the long run, makes no sense... However, after checking out some YouTube vids and then applying proper technical experience, I think I modded something here that will almost last forever and make a lot of glitchy racket as well!

Here is a soundbite of this unit. WARNING! This demo could blow your speakers or wake up your wife & kids! This unit sounds like it is geared more for Rhythm glitching rather than tone glitching. There are a couple of potentiometers that control feedback and distortion using the existing internal OP-AMPs without adding extra gain stages. There are also 2-way switches that will select glitching, add rhythm pulses and HI / LOW frequency feedback generation. The mods have been designed to allow for stock operation if desired - as if nothing was ever done to the unit in the first place. Also, there is a reset button just in case something gets out-of-control and takes over PLUS a line out jack for amplifier use or recording. Granted, there are other mods on YouTube for this unit that are pretty impressive - especially with the glitching but this unit has a sound as well. From what I am to understand - to circuit bend something is to use what is already there - that is the challenge - some folks will add logic and other semiconductor devices to get really interesting effects! Special thanks to Daniel Baum for the how-to and inspiration! [-marty]

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Pedal: Vintage MP-1 Maestro Phaser True Bypass and LED Modification

The owner of this pedal wanted a true-bypass modification with LED on the face to show it is in effect mode. I said "Uh...are you sure? I would have to drill a hole on the faceplate..." He said it would be fine with him. Now, not only does this pedal sound AWESOME, but it has an interesting 60's / 70's vibe and build to it - AMAZINGLY heavy-duty - as pure as analog can be! Pedals, like this one, are no longer constructed to handle the span between a light-toe touch and an industrial sh*t-kicking boot. So, with all that said, installing the TPDT footswitch wasn't too bad as no-one can really see it. However, the fact that I was being ALLOWED TO DRILL into the faceplate for an LED gave me a bad case of dyspepsia.

The solution was to place the LEDs inside the two clear plastic side knobs. Yay! The faceplate has been spared! You have to agree - it really does look pretty cool! Oh, yeah, a DC input connector was installed as well - these units do not have that feature. Why didn't Maestro include all this neat stuff in the first place?

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Amplifiers: Multivox Premier Amps

Owner: Mr. Coe

Condition: Fair to Good - Grills are a little stained.

Shown above are two Premier amplifiers made by a company called MULTIVOX Corporation of America in New York City - sounds impressive!. On the left, we have a model 100R and on the right, a G2R.

The 100R uses a pair of 6L6's and really sounds clear and clean - sort of Fender-like although a different color of tone - this amp is very light and can be used for almost anything. The G2R is much more reserved - I found it not as tonally pleasing but still sounded pretty good. It uses a 6BM8 tube for the reverb and a pair of 7591's for a total of 16 to 20 watts on the output.

Both use a 12" speaker and have tremolo (vibrato) as well. The 100R still has the original cast metal footswitch.

MAN! Check out the logo on the G2R! Perfect! [-marty]

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Amplifiers: Danelectro "Clover" Triplets

Owner: Mr. Coe

Condition: Fair to Good. These are very unique amplifiers with a BIG sound!

The four-leaf "clover" amps (due to the front baffle shape) are an interesting lot. Looking at the picture above, from left to right, we have a Maestro (series C), a Virtuoso and a Special.

The Special, on the right, is my favorite of this lot as it sounds crispy and begins to overdrive properly when used in tandem with a guitars volume control. This little and very light amplifier packs an 18 watt punch using two 6V6s - the preamp and vibrato use three 6SJ7s - all powered by a 6X5 rectifier. What I believe is truly "special" about this Special is the Vibrato! It is the power tube grid bias type and sounds very pleasing to the ear - similar to an old Tweed-era vibrato.

The Virtuoso is pretty loud for it's size! It clocks at about 36 watts (only 3dB more than the Special - you would think it would be a little louder). NO! It is a lot LOUDER! Sonically, the "loudness" of this amplifier is easy to listen to and seems musically louder than one would think - it must be the Rola field-coil speaker inside the enclosure that helps with the warmth but who really knows - we can only speculate...

The real interesting part of this amp is the Filament circuit. One of the tubes is a 12SJ7 and the filament is energized by the center tap of the power transformer. HUH? How does that work? Isn't the center tap usually "0" volts? Why didn't the engineer just take the opposite taps for the 12.6vac? Well, there could be an issue with hum or noise here (or maybe a patent issue as well...). So, by placing an electrolytic capacitor's positive plate on the center tap of the filament secondary and referencing the other plate to chassis ground, the new "virtual 0v" rail will "float" above actual 0v. Since electrolytic capacitors like to charge on their own anyway and assuming the positive charged elements within the vacuum tubes tooling have anything to do with the charging effect, the voltage rises and stabilizes based on the Rx and Cx time constant curve. There is a "happy place" that allows just enough voltage at Cx and just enough current to flow through Rx to energize the 12SJ7 filament. [-marty]

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Amplifiers: 3 of them! - "Leopards and Cheetah"

Model: Fender Ultimate Chorus


Model: SUNN Enforcer


Model: Marshall "Cadillac" JMP - Modified!

All three of amplifiers crack me up! Each one has a story on how they came to be and the owners were more than happy to tell them! [-marty]

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Amplifier: Ampeg Reverberocket 2 - 1965/1966-ish

Owner: Steve Morgan

Condition: Fair to Good++ (Small scratches on front panel - handle is frayed - Tolex is slightly marred and grill cloth is stained - same as any other Ampeg of this age)

Man, what a find --- I really wanted to work on this one!! Steve told me "wait 'til you hear it..." He was correct in every way ( I knew it!) -- this amp really has a glassy tone with round warmth. The reverb (original pan by the way!) really added depth to the sound. I have never seen an "RR2" version and I looked through three vintage Ampeg service manuals full of schematics and could not find this one. I don't think there are too many of these out there...

This amplifier reacts the way I like! The tone of the guitar is clean and gets louder as you bring up the volume BUT, when you get closer to that magic sweet spot, it starts to rev up and really sound good. It is just-left-of-slightly-overdriven without those harsh overtones! Maybe that CTS has a lot to do with it! Thanks Steve! [-marty]

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Amplifier: Fender Harvard Amp - 1955 to 1961 c.e.

Owner: Jorge A. Beliz Jr.

Condition: Another amp that has seen better times but again -- CHARACTER!!!!

email: "My grandfather Freddy played Lap-Steel with it..."


Here is another example of Fender's simplicity in design from the late fifties! I believe it is a 5F10. I really like the sound of this amp because it has a 12" speaker in it - Originally, they were manufactured with a 10" speaker but this one has been modified - I would have used an alnico Jensen but I guess the Celestion would do. It distorts well when turned up but was also a lot cleaner than the smaller Champ amp - I think it is because of the 6AV6 single triode tube in the front of the preamp. It really is perfect for a lap steel or a Gibson L7 or any other hollow body guitar with pickups that sound darker and lighter than a modern humbucker == yeah, yeah, a strat or tele would be ok too...

Two 6V6 tubes in the output section and the 6AV6 really give this guy a smoother tone == the power supply uses a 5Y3 and the V+ will crash when loud chords are played but, it's a tweed -- just how I like 'em! [-marty]

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Amplifier: Two Fender Amps: Black Face 1964 Deluxe amp and 1963 Princeton.

Owner: Rocky Carrasco

Condition: Very Good! These amps are used quite a bit for gigging but Mr. Carrasco has succeeded in keeping them really nice and clean and running great!


Low power amps are really popular - especially during these recent times! They sound great at full volume! I wanted to turn both of these baby's up but, I must remain a professional and try not to "rock out" on customer gear. Both of these amplifiers sound just like little monsters - lots of bite yet pure and smooth. I still say a black face amp sounds better than anything new you could ever buy -- which should really make you think... How old are these amps? Both have the original transformers in them -- Rocky still uses them to gig... THEY STILL WORK! So, with that said, don't be a "pink-o" and BUY AMERICAN MADE INSTRUMENTS!!!!!! For the most part, you will NEVER see amps like these in a land fill.

Rocky and I have had many conversations regarding 6V6 tubes. Which 6V6 tubes are the best to use in these amps? We found that the RCA Black plate was the best. The gray plate sounds good as well. The old Sylvania brand is pretty good but are just as hard to find as the RCAs -- So, what to do? We tried the JJ and although they are not like the Sylvania or RCA, they were the closest to vintage - not too harsh! -- all the others are sub-standard (aka: crap). Thanks, Rocky! Nice Amps! [-marty]

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Amplifier: Fender Princeton Reverb-Amp - "OF" Date code (June, 1965)

Owner: Glenn Carels

Condition: Very Good+! This amplifier is in REALLY NICE shape - Owner says that it was hidden (almost forgotten) in his dad's garage!

This Princeton Reverb-Amp is a dream come true! This is something you would be blessed to find in a garage somewhere! Glenn sent us a note after we serviced his hidden jewel:

"Since I brought my amp back from your shop four hours ago, I cannot stop playing. My Gibson Les Paul (P 90 pickups) and Lucielle sounds amazing through this Fender amp. I am grateful to you for bringing my amp back to life! The tone is crystal clear with warm overtones and begins to break up just enough when I begin to push a little. This amplifier has not sounded this good for a very long time. I forgot how sweet it sounds! Your approach of retaining as much of the original parts to retain the vintage tone while being balanced by the new parts for reliability is genius... ...I appreciate your efforts, passion and commitment to your craft. I wanted to take a break from playing to write this email and say thank you. I am once again inspired to play."

Genius?!? OK, that is a little bit over the top but I will agree with the passion and commitment part! YES! Working on beautiful examples of American Engineering (something mainstream manufacturers have forgotten...) always turns my screws!

Keeping circuits as original as possible is important! We want to preserve as much of the original tone as possible here! So, with the exception of what is considered "wear parts," we left the original components in place with a couple of differences. First of all, instead of installing an "off shore" brand of bias capacitor, a Sprague Atom was put in to "keep it American." Anything else would have been blasphemy! On the other hand, someone early on decided to install Actual English Mullard 12AX7s in the Vibrato and Phase inverter sockets. Cool but we want to hear the Mullard - not the "dead" RCA 7025 in the header socket! So, why not switch out the 7025 with the Mullard in the Phase inverter? Not crazy but practical - what a difference!!! The 7025 makes a great phase inverter for this amp and was clean as F*CK! So, now we can hear the breakup of the Mullard 12AX7 with the smooth RCA 7025 phase inverter to a pair of JJ 6V6s! Installing another Mullard in the phase inverter socket would be too hot and crisp! --- oh yeah, the recto was replaced as well with a Sovtek 5AR4. Thanks, Glenn! A Pleasure! [-marty]

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Amplifier: Fender Tweed Champ 5F1 circa 1962 c.e.

Owner: Rich Salaja

Condition: A little beat up - Ahh! but, what character! The stories this amp could tell!


This is one of the simplest, early production amps Fender had ever made (aside from the little catalog amps sold by Sears may moons ago). This little guy was, and still is, used professionally and can withstand a fair amount of abuse -- it is also one of many amp models that have been cloned and copied and modified and blown up and resurrected and continues to this day to be a standard for excellence!

As you can see, we installed NOS (Sylvania 12AX7, RCA 5Y3, Tungsol 6V6) tubes in this one because, well, I just cannot see it any other way. Vintage tubes for a vintage amp! This Champ has a modest 5 watts of power and a single volume control - NO TONE CONTROL - what for? No-one uses the tone control anyway! [-marty]

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Amplifier: Fender Super Reverb circa 1965 c.e.

Owner: Rich Salaja

Condition: Pretty good - Minor bruises but I call them battle scars - grill cloth is great!


OK... I am going to make this quite clear. THIS IS THE ABSOLUTE BEST SOUNDING BLACK FACE SUPER I HAVE EVER HEARD IN MY ENTIRE 23 YEAR CAREER OF AMP LISTENING! Yea, she has taken a few hits but WOW! - what a silky sound! This amp is pretty much the same as any other super but there is one minor difference - which is what makes this amplifier sound so great -- the tubes. Yup, the tubes made all the difference in this amp -- super quiet and super clear. So, what are they you ask? Forget about it! That is Rich's secret (now mine) - and don't try to blow up the image to see what they are because I have already blurred them out! --- and NO, they are not 12Ablah-blah-blahs or 70xx or 57xx doohickeys. These wonderful and bell-tone-like sounding tubes are very rare and hard to get. I may never own any like these but I will try to find them for my twin.

The back of this amp shows 4 Jenson 10's that are pretty worn in but sound nice anyway -- they may be the trick to why any amp sounds so "warm" or "worn-in" rather -- not the fact that they are Jensons but more-so the fact that they are pretty comfortable to listen to -- kinda like wearing old sneakers. This is a really nice amp =-= thank you for sharing Rich! [-marty]

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Amplifier: Bell 3725, xxxx - circa 1940's? - 1960's? c.e.

Owner: Max Walters / Rich Hernandez

Condition: Fair to pretty good (for an old monophonic pre/power amp...) Lots of scratches but who cares!

Website: "The Turn Out Prose" on MySpace

When Rich came to me and asked if could modify a BELL pre/power amp into a guitar amp, I thought he was joking but after thinking about it: "a guitar amp? SURE!" I took on the task and 12 watts later, success!

His Bell amp sounded so good that his friend Max found another one (Red - first pic) that was even older and wanted the same mod. Success AGAIN! Now there are two Bell amps out in the world that sound really great as guitar amps! [-marty]

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Amplifier: Jim Kelley - Reverb Model circa 1980's? c.e.

Owner: Curtis Eilenberg

Condition: Excellent! Wicker grill is pristine! Wood enclosure is very nice with no scratches!

email: "I bought my first single channel head from Jim Kelley in the 80's... It has a very sweet, warm, powerful sound -- replaced the JBL E-120 with a Jensen."


What a shame Jim Kelly decided to stop making amps like this one or at least stop designing them under his own name brand! It has a really smooth tone in the mid-range when overdriven. The clean sound is nice with hints of "ground round" - kinda like a Fender Deluxe on steroids! We clocked this baby at about 36 watts. The inside is impressive as well - Totally hand wired!

As you can see, the inside of the chassis is CLEAN and very simple - there are no LDRs, FETs, relays, reed switches or anything else that would make the tone a little "cloudy." This amp was built simply and efficiently. That is why it sounds so transparent! [-marty]

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Amplifier: Another Jim Kelley - Reverb Model 2? circa 1980's? c.e.

Owner: Curtis Eilenberg

Condition: Excellent! Tolex Great! Almost Perfect!



OK = Another gem from a great amp maker. A bit like the other Reverb model only this one has channel switching using some of the most industrial grade multi-contact relays I have ever seen in an amp. Those suckers really go "Ka-Chunk" when they switch but not through the speaker. You can rent both of these beautiful Jim Kelly amps (among a large selection of others and vintage guitars) at

"Matched for Jim Kelly..." Wow... --aaand these REALLY have lasted for all this time!?! Hmm... [-marty]

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Amplifier: Gibson GA30 circa 1953? c.e.

Owner: Jason Mills

Condition: Fair to Good (slight water damage on chassis and a funky galvanized metal handle-not original. Picture below is shown with the back panel removed)

This little amp is by far the most interesting and smoothest sounding machine I have ever heard for its age. It has two speakers -- each with its own unique tone. The combination is wonderful! The timbre this amp delivers cannot be reproduced unless you use the same tube types that are in it (see pic).

This picture shows the tube types in their proper locations: 5Y3, 6V6(2), 6SQ7(2) and a 6SJ7. I guess the only way to describe the tone of this amp is to compare it to the preamp and amplifier sections of an old 1950s DELCO tube car radio(you know, the ones with the vibrators that rattle when they start to fail). If you hook one of those suckers up to a couple of decent speakers, you would be quite surprised how fantastic (aside from the AM noise and hiss) an old car radio sounds -- really smooth! It has to be the 6SQ7s dual triode and the 6SJ7 pentode tubes with the metal envelopes. I am told by other techs that they hate these tubes because they sound like crap but I disagree. These tubes definitely contribute to this machines sonic characteristics. Bravo! Thanks Jason, I enjoyed servicing this one! [-marty]

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Amplifier: Fender Bandmaster AB763

Owner: Art Brueggeman

email: "I collect vintage Fender amps, and this Bandmaster was a real FIND!! -- have the matching cab, original covers and footswitch."

Condition: Good to Excellent (Small scratches on front panel - white powder corrosion on chassis - same as any other fender of this age)

This amp is by far the most original one I have ever had in my shop. It is really pretty and in very good condition. ALL components were original before the repair. We replaced a couple of parts but really, it made hardly any difference on the tone!!!

This picture shows how clean and almost perfect the inside is. Notice the 10% carbon composition resistors and the paper capacitors. I believe this machine is still functional because it has been used all this time and has not been sitting around drying up. No crackling, No loud buzz or hiss -- even the power supply caps are still good --WOW!! Thanks Art, you are correct, this is a find! [-marty]

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Amplifier: Fender Pro Amp 6G5

Owner: Andy Siara


Condition: Poor to Fair (lots of scratches, tolex damage and blemishes everywhere - this is to be expected!! This amp has been used a lot!)

The Pro is one of those amps you never see around -- not like a Twin or a Super. It has a sound similar to a brown amp -- it breaks up and is muddier than heck!! All six preamp tubes are 7025s and the two 6L6s drive a 15" speaker!

I have to say, I was mighty impressed with the sound! I plugged my bullet into it, broke out my harp and turned it up (not too loud though out of respect for the machine and the owner...) BLISS!! The back of this amp states "Fender Electric Instrument Co. Fullerton CA. Great tone! It is a wonder why there aren't more of these beauties. [-marty]

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Amplifier: Fender Twin Reverb circa 1965 c.e.

Owner: ME !!!!

Condition: Excellent!

email: "What can I say -- This amp is my favorite! It sounds PURE and clean and works well with my pedal board (that is a different photo and will be posted sometime in the future...)"


First of all, let's start this section with my favorite amp from 1965 -- the black face Fender Twin Reverb. "Did you modify it?" you ask... No. But, I did improve it's functional characteristics - alnico speakers, NOS black plate RCA 6L6's, new plate resistors, MINIMAL capacitor replacement, blah - blah - blah - all the usual stuff without altering any semiconductor values! [-marty]

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