Found shorted output transistors in right channel , left channel is ok. Original – SJ2517 and SJ2518 . Installed NTE 180 and NTE181. NTE 181 must be on top. No modification or adjustments needed. Direct replacement.
Year: 2025
Repair case # 879655. 03/06/2025 Krell KAV-3250 amplifier . No sound on one channel.
Repair case # 879655. 03/06/2025 Krell KAV-3250 amplifier . No sound on one channel.
Nice amplifier. Massive power transformer, has 3 separate independent audio modules containing preamp, driver and output section. Nice technical design, detailed components work. All modules are interchangeable. European school schematic design and idea, strong casing , good outlook , powerful amp. Minuses – use SMD capacitors in hard working schematic like this is not perfect idea. Modules develops lots of heat and destroying those capacitors fast. After 5 years they all are waste.
Troubleshooting – found shorted output transistors (6) , cracked soldering joints on board ( output transistor legs) , all 6 SMD capacitors are dead.
Unit returned to life after re-soldering cracked joints, 2 fuses , 6 transistors, 6 capacitors SMD.
Case 234511. Date 02/24/2025 . Technics SU-8600 amplifier. No sound.
Case 234511. Date 02/24/2025 . Technics SU-8600 amplifier. No sound.
Both channels not working. Protection Relay 
,t click.
Capacitor c506 100 uf x 63v in power supply section is dead. On picture new installed it is dark brown color capacitor in center , original was light blue. After replacement unit is working properly. Standard deep cleaning, controls cleaning and testing performed .