THD

The THD Hot Plates are attenuators which allow you to drive your valve amp at maximum gain but at low volume. This makes it a great addition for recording or practice where you can get all the drive sounds you need without the need to have sound re-inforcement in your studio. Note each is optimized for a specific impedance (2, 2.7, 4, 8, or 16 ohms.). Choose the one that fits the impedance on your amp. See more information for a technical explanation of how an attenuator works.
More...

The THD Yellow Jackets are specialized adapters which permit the use of EL84/6BQ5 power tubes in place of 6V6, 6L6, EL34, 7027 6550 (under 520 volts) and 7591 types. They will work in any amplifier that takes these tube types, as long as the plate voltage is under 520 VDC. This accounts for over 98% of the tube guitar amplifiers on the market. (They also work in tube Hi-Fi equipment!) Because the Yellow Jackets ignore the amplifier's grid bias voltage, it is possible to take them in and out at will to adjust your power level and sound for the individual gig or session. Class-A With Any Amp!
More...