Guitar Amp - What Kind?

[CJ]

in the shop today , nice antique, no name on chassis or cab, anybody have a clue what this is? Thanks!

 

[musika]

Kamico Musical Instrument Amplifier unknown Ampl/Mixer Kay Musical

 

[CJ]

Dang! That was fast! Thanks Musika!

 

[Flatpicker]

Wow! I've never heard of those. It looks strikingly similar to Leo's Woodies which came out that same year. Wonder which came first - the chicken or the egg? Hmmmmmm

 

[musika]

That is old.... 1946 (even a few years older that me!). Maybe one of the first guitar amps ever made? No controls - or is that a volume pot on the back side?

 

[Rusan]

Wow! I've never heard of those. It looks strikingly similar to Leo's Woodies which came out that same year. Wonder which came first - the chicken or the egg? Hmmmmmm

I don't know whose amplifier came out first, but Kay predates Fender as a company by many years.

That's a really neat old amp, and with a UX4 base 80 rectifier instead of the octal equivalent 5Y3. How cool is that?

It's also interesting that it has a 6SJ7 and 6F6. Many of those types of guitar amps were designed with tubes having very high heater voltages, so their filaments could be strung together in series with a proper value resistor and powered directly by the AC line. Not exactly good engineering practice, but it allowed the power transformer to be smaller and cheaper. Televisions especially used tubes with specific heater voltages for use in series heater strings. The highest voltage filament used the full AC line voltage and dropped it to the next filament's required voltage and so on, until you finally got to the last tube that might be 3 or so volts.

Series AC line heater strings, death caps, unpolarized AC plugs and accessory jacks on radio receivers carrying full B+ were some scary stuff.

 

[andYz00m]

I think Uncle Doug restored one of these in a video. Ill try and find it.

 

[CJ]

There is a guy blowing some cool harp on you tube, this one has the electro mag speaker replaced. We also have a Gibson GA 90 in the house with eight 8 inch speakers in the wood cabinet.

 

[CJ]

Make that six 8 inch speakers, do not have edit button on phone wtf?

 

[Rusan]

I think Uncle Doug restored one of these....

That got me to thinking about all the old amps and tuners I repaired or restored back in my day. It made me chuckle when I recalled this particular '66 blackface Bassman head.

The owner said it smelled "hot" and was humming. When I opened it up, I immediately noticed one of the screen grid resistors was burnt, which those of you who work on vintage Fenders know is not unusual. You'll frequently see the color bands scorched from overheating, but this one was actually completely burned up on one end. Charcoal. Toast. Even worse, one of the power transformer primary leads had been cut too short during assembly, and was stretched tight from the power switch to the transformer across pin 4 of one of the 6L6 sockets! The solder on that lug was dull, gray and highly oxidized from having been overheated so many times. Miraculously, the cloth insulation of that primary lead somehow wasn't burned through enough yet to be making contact with the lug, although it did look rough.

My first thought was, "That thing had to have been arcing. Why didn't it blow the fuse? Hey, wait a minute..."

I removed the fuse holder cap, and guess what? Sure enough, the old "aluminum foil wrapped around the fuse" trick.

The (then) nearly 40 year old owner had proudly boasted that the amp was a 12th birthday gift from his father, so one would assume it should have had at least *some* value to him. Instead, it was extremely dirty inside and out, had two different brands of power tubes (both completely worn out), and he'd been playing it for months in that present condition before having it serviced. I told him it was a miracle he didn't fry one or both transformers.

We also have a Gibson GA 90 in the house with eight 8 inch speakers in the wood cabinet.

Wow CJ, that's a cool (and rare) old amp!

 

[Brian Roth]

Quoting:

"I removed the fuse holder cap, and guess what? Sure enough, the old "aluminum foil wrapped around the fuse" trick."

We used to call those a Wrigley 100 Amp no-blo fuse....

Bri

 

[dougsta]

Wow! I've never heard of those. It looks strikingly similar to Leo's Woodies which came out that same year. Wonder which came first - the chicken or the egg? Hmmmmmm

Leo was a radio repair man, a few mods to a table top radio and hey presto a guitar amp.

 

[Rusan]

Quoting:

"I removed the fuse holder cap, and guess what? Sure enough, the old "aluminum foil wrapped around the fuse" trick."

We used to call those a Wrigley 100 Amp no-blo fuse....

Bri

Leo was a radio repair man, a few mods to a table top radio and hey presto a guitar amp.

Leo's amps and guitars changed the face of music overnight, spawned countless copycats and forever influenced the design of electric stringed instruments in a way nothing else has. What's always been amazing to me is that even though Leo was an electronics guy, he wasn't a guitar player. But, he was obviously a brilliant businessman, who changed the world.

 

[mjrippe]

I swear that 50% of the guitar amps I have repaired had the wrong value/type fuse. It is the first thing I check, always before putting it on the Variac. I told one owner that his Fender Champ would literally be on fire before the fuse blew!

 

[AnalogPackrat]

Leo's amps and guitars changed the face of music overnight, spawned countless copycats and forever influenced the design of electric stringed instruments in a way nothing else has. What's always been amazing to me is that even though Leo was an electronics guy, he wasn't a guitar player. But, he was obviously a brilliant businessman, who changed the world.

Leo understood two important things that made a big difference. 1) make amps easy to service, 2) listen to your customer. He wasn't a player, but listened to his friends and customers who were. Leo was able to find cost-effective ways to meet the needs of most players. And easy to service amps kept them playing.

I helped a friend fix an early 70s Ampeg 1x12 combo roughly comparable to a Deluxe Reverb a few years back. What a PITA that thing was. Sounded good, but poor design.

 

[Rusan]

I swear that 50% of the guitar amps I have repaired had the wrong value/type fuse. It is the first thing I check, always before putting it on the Variac. I told one owner that his Fender Champ would literally be on fire before the fuse blew!

Hey, I know that guy too!

"This thing keeps blowing fuses! Well, I'll fix THAT! Hand me that box of 30 amp fuses."

That relates to item #1 on the "10 Infallible Rules of Amplifier Repair" poster I used to have on the wall, which says "The power transformer will always blow to protect the fuse."

I helped a friend fix an early 70s Ampeg 1x12 combo roughly comparable to a Deluxe Reverb a few years back. What a PITA that thing was. Sounded good, but poor design.

Yep, they're like an old Vox; "clutter city." I have one of Jess Oliver's post-Ampeg creations in for a complete rebuild right now, a 1972 Oliver PA100-XR 2-channel PA amplifier head. It's not bad, but not super easy to work on like an old Fender or pre-'73 Marshalls. Like all the big Ampegs he designed during his tenure there, the thing has stoopit high B+. He definitely believed in squeezing every last milliwatt out of the finals, no matter the cost.

 

[Nick Nack]

Leo's amps and guitars changed the face of music overnight, spawned countless copycats and forever influenced the design of electric stringed instruments in a way nothing else has. What's always been amazing to me is that even though Leo was an electronics guy, he wasn't a guitar player. But, he was obviously a brilliant businessman, who changed the world.

And just think; if he'd been a yorkshireman, the guitar that Jimi Hendrix torched onstage would have been a Fender Tadcaster.

 

[CJ]

here is that Gibson,

 

[CJ]

this is going out tuesday so the boss wants me to check it out,

 

[Rusan]

Drool, drool, drool....

That Bassman reminds me of a cool story you guitar amp guys will like:

A friend of mine used to manage a local music store. One day, a guy walked in with an early blond Tremolux head, which he said didn't work and would blow fuses. The guy was just learning to play and really only needed something to amplify his guitar with, and hoped he could at least get *something* for it. My friend asked if he'd take an old Crate combo amp they had as an even swap. He did.

The owner took it back to the bench, and was rather surprised to find it had EL84 power tubes. He thought it was odd, but nothing more, and put it up on a display shelf with some other vintage Fenders, where it sat for at least 20 years.

A friend of his came in one day with his buddy, who was visiting from another state. He said his buddy was a true expert on all things Fender, so he showed him the oddball Tremolux. The guy didn't say anything then, but called him at the store a couple of days later to tell him what he had. It was an ultra-rare 6G9 Tremolux that less than 200 of were made, with far fewer thought to still exist, much less in original, unmodified condition.

He closed the store a couple of years ago and retired, and was selling his Fender and Altec collections. I asked if he still had the Tremolux, and he said he'd sold it, but wouldn't say for how much. I recently saw one on Reverb for $4,900 CAD.