As new, including box, 4 ohm version….How does a Hot Plate® work? A THD Hot Plate® is a tuned network of capacitors, resistors and inductors which adjusts the overall EQ as the volume is turned down to compensate for the human ear”s frequency response. Your ear perceives sounds differently at different volumes: the louder the sound, the more sensitive your ears are to highs and lows. As the volume drops, your ear becomes more sensitive to the mid-range, and less so for highs and lows. The Hot Plate® compensates for this, working like the “Loudness” switch on a hi-fi. The THD Hot Plate® is the first, and for now, the only attenuator that is frequency compensated. How do I use it? The THD Hot Plate® is designed for use strictly with vacuum tube guitar amplifiers, and each version is optimized for a specific impedance (2, 2.7, 4, 8, or 16 ohms.) These inductive loads are frequency compensated, which means it will give you the best possible sound for that impedance speaker and amplifier combination.
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