IWISTAO HIFI Mini Tube Amplifier 2x3W Class A Single-ended 6J1 Preamplifier 6P1 Power Stage plus Tone Adjustment Preamp
This is a mini class A single-ended tube amplifier, which use tube 6J1 as a preamplifier, and tube 6P1 as a power stage. Especially, it adopted switching power supply instead of power transformer to reduce the weight and volume of tube amplifier, also adopted boost circuitry to provide high voltage, its background noise is mostly between 0.5 mV to 1 mV, when volume potentiometer close to the minimum, and your ear touch to the speaker, and hum is not likely to be heard.
And, the preamplifier has tone control functions and adopts class A power, sound extremely delicate, slender high-frequency, low frequency plump and elastic, if use top op amp IC like as OPA2604 or LME49720, it will achieve perfect sound. Specially, it used a R-type audio dedicated transformer. And it has direct access function; you can skip tone adjustment to achieve original sound completely.
When audio sourcing record, speaker unit, placing the device is not necessarily perfect, and if your preamplifier adopt pure straight, it may not be able to meet the demand. At this moment, add tone adjustment function is very important. If you no extra power supply equipment, passive preamp tone is preferred, which can enhance the effect of high and low frequency is obvious.
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