Soundcraftsmen DJ900 (refurbished)

Soundcraftsmen DJ900 power amplifier

SERVICED:
*replaced all electrolytic capacitors with quality Nichicon audio capacitors
*replaced large power capacitors with upgraded higher rated capacitors
*replaced differential input transistors with matched pairs of upgraded type
*replaced input constant current transistors
*set and tested phase control voltage and temperature protection voltages and operation
*repainted cover
*installed new rubber feet
*tested distortion(<0.05%) and played

This model is a powerful, tough built amp. The DJ900 is the heavy duty version with 6 MOSFET output transistors per channel. It uses phase control regulation to regulate running voltage and self adjusts to temperature sensed at different spots on the heat-sink and transformer.  It will run without shutting down even at the lowest impedances. All electrolytic capacitors were replaced with audio capacitors from Nichicon. The power capacitors were replaced with 13,000uF 100V capacitors where the originals were 11,000uF 75V. The new ones are also rated for a ripple current of over 15 amps each and an 18,000 hour life-span. That will keep up with the most demanding power hungry music for a long time. The PCR temp and voltage settings were adjusted and tested for performance and thermal stability. This amp got the full treatment because it was in good condition and I felt it was a worthy candidate. Someone will enjoy this and know they get the best sound and fresh parts to last. Thanks for looking.

Specs:
-205 watt RMS per channel 8 ohm, 300 watt RMS per channel 4 ohm,  450 watt per channel 2 ohm
 600W 8 ohm and 900W 4 ohm in mono bridged operation
-THD <0.05%
-IMD  <0.05%
-TIM immeasurable
-S/N >105 dB
-Damping factor >250
-Slew rate >40 V/uS
-Rise time <2.2 uS
-Frequency response +/- 0.1dB 20hz-20khz