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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.

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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 .