1956 Voice of Music8 watt amplifier

This was a fun one. 1956 (or so) Voice of Music 8 watt amplifier. I like that it's just called "8 Watt Amplifier". No fancy school names, nothing clever to shift more units of these babies!



Complaint was it's dead! Lights on but nobody home. That's a good thing. Always easier to fix a dead amp than one with annoying intermittent problems. In this case all those beautiful Mica Mold capacitors were just plain dead. I also replaced the filter caps and added a cap to the 300 ohm cathode resistor on the 6v6 output tubes. This helps low end response while also helping tame some hum away. So it ain't on the schematic. Who cares? Let's improve it!

Super cool slide out chassis:




10" Jensen Alnico 5 speaker! Worth the price of admission.




Some shots of the not 'mil spec' bowl o' spaghetti design:



Mica Mold Capacitors! I'd love to hear a fresh set, never have. They're almost always leaky. One read a whopping 114 vdc on the potentiometer side!



But either way, they sure are pretty. I replaced them with a set of Mojo Dijon for the preamp, and Sprague 225P polyester Orange Drop caps for the phase inverter. An amp like this can benefit from that setup, very clear and warm, but not mushy.



Shot of the filter cap. I upgraded the 470ohm 3 watt resistor with a 500 ohm 5 watt. Also used 2 watters for the 10k power resistors. I like to never see an amp again once it leaves so why not?



Cap dated 47th week of 1956!




Schematic included! I love that. No guesswork if something is burnt.





I love the speaker connectors.




How does it sound? Perfect for what I like. It's not your Neil Young rage box, it's subtle and sweet. Very open and clear sounding. This was never intended for guitar, it's a PA amp. It's the kind of thing I'd use in my living room while someone is playing a big Gibson J45 or  Martin D-18. It gets only slightly louder than one of those at full strum. Perfect accompaniment amp.

Single 5Y3, pair of 6V6 tubes driven by a 12AX7 and a 12AY7. Same tube compliment as a Tweed Deluxe but completely different sound due to a completely different circuit. So if you like something fresh and unusual, seek one out! This is a lovely amp to look at as well as play. And I like nice looking things in my living room. 

-J

1963 Fender Vibroverb. One of the rarest of all.

I had the honor to work on this old Vibroverb last month. At first glance I thought is was a reissue model cause it's so clean. I looked at it again and said "No way!" thinking it must be a kit. Then I realized I know the owner and he has pretty fine stuff.

I've never seen one in person. This goes on my bucket list of rare Fender amps like the 3x10" tweed Bandmaster here.

Amp was blowing fuses. The filter caps were bubbling so I replaced them but unfortunately the problem was the reverb driver transformer was shorted. BUMMER! Nobody makes quite the same part so I just used a new Heyboer with a large washer to hold one end on. No holes needed to be drilled this way and no one is ever going to see it anyway. Easy fix.

The original part goes into a plastic sandwich bag so the owner can decide what to do with it. Paperweight or get it re-wound? He doesn't care since he doesn't use reverb anyway.

Amp sounds amazing. First model to sport those 'brick drop' caps like you see in late 60's models.

Did I mention this amp sounds amazing? I'd go so far as to say aggressive. If cost were no object....



The culprit:





Brick drops!








Original speakers. At some point they were wired backwards! I've seen this many times....




Original milk chocolate footswitch. Mmmmmmm.....

Little Silvertone 1471. 5 watt killer!

Another gem from Indigo Ranch that's been sitting on a shelf since the 90's! This belongs to Sonic Circus as well.




It was totally dead, ripped mouse eaten speaker and all. Found a cool Utah to throw in, re-capped it and it's making music again.

Circuit is similar to your classic tweed Princeton (Champ with a tone control) and it's got a great early Eric Clapton type of sound. Smooth breakup, warm but good bite.. I particularly liked the low end. Smooth and creamy not unlike Billy Gibbons. I just want to play some ZZ Top on this amp.

Simple 6V6 driven by a 12AX7 with a compact 6X4 rectifier.

Here's a funny video of it's first few notes after 30 years of being mothballed.

https://www.youtube.com/watch?v=sumDxmeaeP0



And some photos!











Planet Capacitor, guaranteed for 1 year!!!





So there you have it. These are cheap as chips. Yes, built rather crappy but who cares. Just don't let it get wet as they are made of pressed paper! Fantastic tone. Who says you need a pine box to cut great tracks anyway?

j

1950 (or so) Gibson BR6F

The first good small tube amp I bought was a Gibson BR6F. I found it at Guitar Exchange in Catonsville, Maryland back in 1992.

I....love....these....amps!

6SJ7 driving a 6SN7 phase inverter feeding 2 hungry little 6V6 tubes. 5Y3 rectifier. 10 watts into a 10" field coil speaker.

A word about the field coil speakers. They often sound lovely. Don't do what I did to mine: run a bunch of pedals into it and blast off for hours. I killed mine and once that speaker is dead, that's it. It'll never be the same. You want to treat the elderly nice and gentle, with respect. Leave those dumb ass pedals in the bag and learn to play better!

I probably could have had that speaker rebuilt, but I blew mine up in 1995. No internet in those days and tough to find someone to rebuild it properly

If you do blow it up, check these cats out:

http://www.thespeakershop.com/home/speakerrepair.html

his one was at Southside Guitars. It's long sold. I re-capped it and replaced the power cable. I hope the new owner just plugs in and plays it!

And a video of my friend Eric playing it.....

https://www.youtube.com/watch?v=_PUzJnwjELg

The amp:

1939 Kalamazoo KEH amplifier built by Gibson

Such a cool amp. This came from a good friend of mine. He bought it at a local shop as-is and it was dead.

I love them when they are dead. It's easier to fix a dead amp than one that sort of works. Example is the Oahu amp I bought in Dallas last year at the guitar show for $100. The power switch was dis-connected. Simple fix. The rest is just change caps and resistors as needed.

This was no exception. Dis-connected wire got it going. I had to re-cap it, ground it and change a couple super microphonic 6C5 tubes but that's it.

These early Gibson amps are exceptionally well made. Easier to work on than what they produced from the 1940s on forward. Odd, cause the early ones are service friendly like a Fender. They got worse over time where Fender just kept getting better. I like how you can simply unplug the field coil speaker in these. You just pull the chassis after that and do your thing.

Plus the looks:









This is one beautiful piece of equipment!

Tubes are 3 6C5 preamp tubes, a single 6L6 and an 80 rectifier tube. They do run rather hot. This one showed evidence of the transformers getting hot. I replaced the cathode bias resistor with a bit higher value. Makes things sound a little 'looser' but you know, I'd hate to see the output transformer die in this 80 year old amp.









Tube sockets were labeled right on the socket itself. Classy!


Yup. From the glory days of American manufacturing. These were factory built. Not cheap! You need to pay a builder to get this kind of quality today. Not cheap but come on, you're worth it!

-J

DaVinci 2x12 "High Fidelity" amp built by Magnatone (model 260)

Here's one that was intimidating. A true barn find full of dead bugs and mouse faeces.... effing gross!

It was sold to my friend Dave at Sonic Circus for $50 a few years back. We weren't expecting much since it had spent so much time growing uglier due to neglect.

But once I cleaned it up, re-capped it, fixed the tears in the speakers it came back to life. And it has of course a gorgeous voice! I'm not a fan of the stereo Magnatone amps, too complicated, oddball expensive tubes, but these simpler ones are the bomb. It's about 25 watts with 2 6L6 tubes. Nothing expensive or difficult to find tube wise either. Just a 5u4 rectifier, some 12AX7 tubes and a 12AU7.

These 'stencil' amps built by Magnatone for other companies are a real bargain. Not exactly cheap but not what you pay for one labeled Magnatone. See my other post for the Panoramic amp I still have.

This amp is basically a Magnatone 260. It's now making music again at Sonic Circus. Dave has a beautiful Vox AC-30 with the copper panel. With the pitch shifting vibrato in the amp the 2 seem spiritually connected. Though, I prefer the Magnatone amps myself. Straight up Bo Diddley tone! Less noisy than the AC30 too, though, no diss on Vox. Those are amazing too.









Do notice the Celestion 'Guitar Center' model speaker I threw in. Not a bad choice but fortunately I was able to get the original speaker going again!



Bowl o' spaghetti construction:





And there you go! Get out there and try one of these. They have quite a sound! J

1965 Fender Showman amplifier. Killer bass or guitar head.

When I was in high school I had a cousin named Bryan. He had issues with telling the truth. But while I didn't trust him I loved the cat anyway. He wasn't a blood relative, just my god brother.

One day he showed up to my house with a Fender Showman, property of the Baltimore City Public School system. Yeah, he stole it.

But whatever. I'm sure they didn't notice it. The amp was missing tubes, badly neglected much like Bryan and that school system. It just needed help.

I was fascinated with the thing. I just wanted to get it working. I opened it up and shocked the hell out of myself on the still charged filter caps. It had power just no sound.

So I found a few tubes for it at Radio Shack and got some resistors that matched. I'm not sure if I even knew what a resistor was in those days. One just was burnt so I had to match it. Yes, Radio Shack in the Columbia Mall sold tubes! Good tubes. Not the crap made today.

I got it working. I remember it sounding like it was underwater, not in a bad way, it was just so warm.

Thus started my fascination with tube amps. And my fascination with the Fender Showman. I think I traded that chassis in on something I bought at Angela Instruments a couple years later. Early on when Steve had his shop in Savage Mill, or maybe in his house. Those were the days!

I did buy a working one when I was in Berklee. I used it for a while. I think I was fascinated as well cause a Marshall Plexi was intimidating to me. A Marshall seemed like an exotic nuclear power source. Yet, when I watched Jimi play Monterrey in the film, he had his Marshall and a glorious Showman amp too. Seemed more manageable to me.

So this one was from Indigo Ranch and had been sitting neglected for a couple or more decades. Simple re-cap, re-tube and there you go. I replace the (either 500pf or .1000pf) cap that feeds the phase inverter with a .002-.005. We're using the amp for a clean 80 watt bass amp. The Showman is 8 ohms, whereas the dual Showman is 4. I prefer these.

Such a beautiful sound......










Old caps. It's dumb but on an amp like this I re-use the sleeves cause they have the dates on them. But folks, do change the filter caps. It's just stupid not to!




Did the usual. New grounded cable yadda yadda..... Transformers are all original and this amp is no longer sad and neglected, its cutting tracks once again at Sonic Circus in Vermont!

J