PRT-08A 12AU7+12AX7*2 + 6N11 Tube Stereo Preamplifier PCB / Kit / Board Base On CAT SL1
PCB size: 154*254*1.6MM FR4
Works voltage:
0-AC220V >=0.05A
0-AC9V >=1A
0-AC14V >=1A
We have the suitable transformer for this board. if you need. please contact us.
This preamp are using 1pcs 12AU7 / 2pcs 12AX7 and 1pcs 6DJ8 (6922)
We can provide the clear PDF schematic via email.
ZERO-ZONE PRT-08A preamp is reference the famous CAT SL1 preamp Circuit , The sound quality is very good. Sharp dynamics, accurate positioning, medium frequency mellow, tube tastes very strong. was considered the almost the perfect tube preamp design.
The CAT-SL1 design tubes are not like the other brands - multiple isotypes; but the targeted tube to meet the school requirements, the first level using U-tube 12AU7, The input tube; the second stage uses a high U tube (12AX7), which is an SRPP structure, taking its bandwidth and buffering between the front and the back, and also preparing for the third level. The third stage is 6DJ8, which has a larger screen output current, so as to push the rear stage power amplifier.
The high-voltage power supply uses a regulated power supply, and the MOS tube is used as a voltage regulating tube to make it more tube tastes tube taste.The filament is divided into two sets of voltage regulators, which respectively supply 12.6V for 12AU7, 12AX7 and 6.3V for 6DJ8 (6922)
In terms of ingredients, using Panasonic and 718 resistors, gold-plated ceramic tube holders, BC-Philips capacitors, ELNA capacitors, etc., high-voltage regulators using the Toshiba and coupling capacitors are ERO+MKP series, which has a high cost performance.
In the PRT-08A, we added a 30 second delay on the output component.Avoid the whistling of the preamp when power on.
