I am currently repairing an old school sound stream reference 500. The only issue remaining after replacing the output transistors is a constant 35AC on one of the speaker terminals.
After searching through other threads, I’ve determined that the rectifier(s) are more than likely causing the issue. Can anyone tell me what the best substitute for these rectifiers would be? According to the schematic, I would need to find substitutes for the FED16BT’s used in this amplifier.
After searching through other threads, I’ve determined that the rectifier(s) are more than likely causing the issue. Can anyone tell me what the best substitute for these rectifiers would be? According to the schematic, I would need to find substitutes for the FED16BT’s used in this amplifier.
Those are dual doubler rectifiers and are harder to find. The only place I’ve found, and the only exception to the eBay rule, is to purchase these from originalparts_nos thru eBay. Normally, never buy from eBay, but this seller can be trusted IMO. This seller usually has lots of hard to find Soundstream parts.
That said, I’ve only ever seen failed rectifiers blow fuses and burn up power supplies. Did you test them with your meter? Normally they come up shorted making the amp non-functional. That also said, they have a high failure rate and so I always replace them even if they measure ok, just for precaution as I’ve seen old ones fail on my bench out of the blue under testing.
Voltage on speaker terminals usually is caused by a shorted output or shorted/leaking driver. Also check switches.
That said, I’ve only ever seen failed rectifiers blow fuses and burn up power supplies. Did you test them with your meter? Normally they come up shorted making the amp non-functional. That also said, they have a high failure rate and so I always replace them even if they measure ok, just for precaution as I’ve seen old ones fail on my bench out of the blue under testing.
Voltage on speaker terminals usually is caused by a shorted output or shorted/leaking driver. Also check switches.
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If a shorted rectifier would cause major issues with the power supply, I possibly have something else bad.
Perry, I measured ~35 AC on one pair of the speaker terminals. I will clean the switches, re-check the rectifiers, and also confirm that it was AC and not DC on the speaker terminals. If I had 1 bad rectifier, wouldn’t that effect a pair of the speaker terminals?
Perry, I measured ~35 AC on one pair of the speaker terminals. I will clean the switches, re-check the rectifiers, and also confirm that it was AC and not DC on the speaker terminals. If I had 1 bad rectifier, wouldn’t that effect a pair of the speaker terminals?
The rectifiers all feed a common pair of rails that are shared by both channels. If the amp had separate sets of rails for each channel, a defective rectifier may be able to affect one channel but that's not the case with this amp (from the diagram I have).
