Tube Preamplifier - Zero Feedback - Pure Analog
This is simplicity and purity. Sorry it doesn't cost more...
We're actually not sorry. We are very pleased to offer this superb value. The PA 555 has 150 volts running a single 12AX7 Tube. The input signal runs directly to the grid of the tube, and the tube provides 11.1 dB of gain. No feedback, no integrated circuits. It doesn't get much simpler than this, nor as pure. If you really want to hear tubes, there is no better way. It’s a pure analog gem, and a stunning value at this price. Try it in a desktop system with the Audience ClairAudient speakers, and a zero negative feedback, Class A, (SET perhaps?) amplifier.
The single 12AX7 tube is directly connected to the audio signal, and provides the gain. It has a huge influence over the sonics presented by the PA555. Try some different tubes to get exactly the sound you prefer.
Roll Power Supplies
One of the ways the PA555 keeps the price tag so low is the wall wart style switching power supply. Even though it sounds great stock, one can do much, much better with a good linear power supply. Heck, even a Jameco linear wall wart supply will provide improvements, just be sure you get a 15 volt DC power supply with at least 500 milliamps of current.
- input connectors: 1x 1/8″ TRS Stereo jack; 3x RCA Stereo jacks
- output connector: RCA Stereo
- power: 15 VDC 500mA
- size: 6″w x 2.5″h x 5.4″d
- dimensions: w6″ x h2.5″ x d5.4″
- weight: 2 lb.
- input impedance: 10k Ohms
- output impedance: 100 Ohms
- max output gain: 11.1dB @ 1kHz at .1% dist.
- thd: .01%
- s/n ratio: 103dB, unweighted
- Crosstalk: -75 dB
- Frequency Response: 5 Hz – 198 KHz +/- 3 db
- Tube: 12ax7