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The Fanton Guitar Amp

The "Fanton HiFi Stereo" amp looks like it was built in the 1950's. Although it is built with inexpensive materials, there are several high quality details: finger joints and a gold piping.

The original amp was built point-to-point and connected directly to AC, which is considered a major electrical hazard. The underlying tone was horrible and it couldn't be fixed without completely rewiring everything.

The new amp is a single-ended 6AK6 with a 12AX7 preamp and GZ34 rectifier tube. It provides about 1 watt of pure tube tone, which perfect for a low power amp!

The circuit is based on the Fender Champ with only one stage of gain and a volume control. We found that this gives the best tone with great crunch and cleans. It is an extremely dynamic amp!

The amp is wired point-to-point with tag boards, which many people believe gives old amps their unique tone. It has a single orange drop coupling capacitor (in the upper left corner) that was originally in the Precision PA amp.

The vintage 6" alnico speaker is a big part of the tone.

It has a Mercury Magnetics Axiom power tranformer for about 300 volts to the 6AK6, which is its maximum rating. The output transformer was custom built by Musical Power Supplies - it's their Champ transformer with a few extra winds.

Perhaps the most interesting part of building this amp (besides restoring a 1950's amp) was the major mistake. The layout was backwards, which meant that I had to switch the order of the preamp tube pins.

I brought the amp to Larry Rodgers to buy the rectifier tube and fire it up for the first time. Larry grabbed his guitar and started playing. The amp sounded gorgeous. I tried changing the tone and volume knobs while Larry kept playing, but they didn't work.

A quick look into the amp showed that I had accidently bypassed the tone stack and second gain stage. Putting them back in resulted in horrible distortion and feedback. Apparently the 6AK6 hates to be pushed too hard!

Larry emphatically suggested returning to that original circuit since the tone was fantastic. Besides, a Champ doesn't have a tone stack. It's not needed if the amp sounds good to begin with.

It's a little odd having treble and bass controls that don't do anything, but tone is the first priority!

Here are some sound files with the amp on 10. I used a Fender Strat. You can hear me switch from the neck to the bridge pickup, and then from single-coil to humbuckers.

The idea was to show how you can get different sounds by switching pickups and varying your playing.


Check out my tube guitar amp repair blog (on MySpace)

Natural health research and writing is my main career. I'm a licensed naturopathic physician. www.naturdoctor.com and LinkedIn

Building and selling tube amps for guitar and HiFi is a hobby based on my previous career as an Electrical Engineer. Ampersand Amps