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THD Amps

THD Amps
3510 6th Avenue W
Seattle, WA 98119 - 1513
Phone: 206.781.5500
Fax: 206.781.5508

THD Amps specializes in tube guitar amps and tube amp modification products. Their Yellow Jacket tube replacements allow you to change your tube amp sound and output wattage with no modifications. Their guitar amps are simply awesome sounding and are in the same ball park as Buddha, and Soldano: boutique amps at their finest. The UniValve was considered the amp of 2001 and their BiValve is a pure Class-A amp and uses a unique output transformer. It allows you to use almost any preamp and power amp tubes. This is one of the things that make these amps so popular. You can completely change the sound and response of the amp by change the type of preamp and power amp tubes. You don't have to re-bias or modify anything.


THD Flexi-50 Class AB Amp Head
THD Flexi-50

The Flexi-50 is a 50 watt class A/B tube guitar amp. This amp is made for the guitarist that wants great sound and quality from their amp. This is one of the hottest sounding boutique amps out. It has a punching A/B sound. This amp is hand built in Seattle Washington. It has a fat sound of the late 50's amercian amps (Class A/B) with an overdriven sound. Even at extreme overdrive you can hear the intricate sounds of your guitar and way of playing comes through. The distortion doesn't mask your tone.

THD Yellow Jackets Replacement
THD Yellow Jackets

With the Yellow Jackets EL84 Replacement you can use it to reduce the output wattage and sound of your amp. On Marshall amps if you can use them to lower the output wattage from 50 watts to 20 watts. It'll also change the tone from the Marshall to more of a Vox. It's really quite a neat thing. On 6L6 output amps like a Marshall 100 or Fender Twin you can use two Yellow Jackets (leave the other two open) and get a very different sound because these replacement tubes run in class A and not A/B which will give you a more compressed and warm sounding amp.


THD UniValve 15W
THD Univalve

The UniValve is a 15-watt class A tube guitar amp. This is one of the best amps out there. The main idea with this amp is that you can put almost any Power Tube, ie. 6L6, 6550, EL34 and others, as well as any preamp tube (12AX7, 12AT7 etc...) in the amp. In essence you can get the Fender Twin sound, or a 1970's Marshall (6550) sound, or a Mesa Boogie wound just by changing the type of tubes. The other amazing thing is that you don't have to re-bias the power tubes, the amp is self biasing.

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