B2 not playing on both channels cleanly for first 20 seconds.

Oh and a key piece of info I should have shared is that I never get any static or repeat of the "poor connection" behavior by playing with the switches in front. It always cuts cleanly off and on. So my initial focus will be the components in the schematic upstream of the speaker relays. Some were already identified above. I am going to pull these and test them first.
 
Good advice in this thread. The input selector and volume control bypass is my favourite modification for this amplifier - and to my ears it resulted in most difference (i.e., improvement) !

When you look at the circuit diagram for this amp, nothing cleans up the signal path more.

Heed Oilmaster's advice, though - you need to add a proper ground.
 
Did you mean TR-220?
No....
TO-220 is a transistor case style.
TO220dwg.gif
 
So...I pulled TR217, TR218 and C223 and they all tested good. But in the process of flipping the power board over a couple of times the BR brown wire broke off from its solder connection because the wire had corroded. Then I noticed that the BE blue wire on the opposite end of the board had the same corrosion problem and was just hanging by a thread. I stripped enough off both wires to get clean wire and re-soldered both.

I connected the amp back up to my main listening system and turned everything else on first so I could hear what it did from a cold start with a music signal playing. As soon as it clicked on it started playing music fine on both channels with no delays like it did before. It has been playing fine for the past hour. It must have been the re-soldering of the BR and BE wires that fixed it because that is the only change I made.

Thanks for all your input and help.
 
I've seen one B-2 with bad corrosion issues on lots of wires and solder connections.:yikes:. A bitch cleaning up that mess.
 
The one I had, had gotten wet.All the solder had heavy white oxidation. Solder doesn't flow very good after its oxidized.
 
Back
Top Bottom