Hi folks,
I'm hoping someone can help me. I have a 31 year old Audionics BT-2 PreAmp. One channel is weak and sounds muddy. The other channel sounds great. I've verified that it is the BT-2 and not the CC-2 Amp.
The other problem is that when the tape switch is in the "Tape" monitor position there is "bleed-through" from any other component that is attached to the BT-2 and turned on -- in other words I can hear the tape but I can also hear another component bleeding through to the speakers.
I did open the case and reattached the volume and balance pots which were loose and turning such that the wires were wrapping around the pots. I didn't find any obvious broken wires or damaged solder joints on the pots. The pots seem to work as they should but the right channel is definitely weaker and muddy sounding. If the balance is mostly on the right channel, the volume does improve but it still sounds muddy compared to the left channel.
I did a bunch of searching on the internet and about the only thing I found of value was a mention of the "dreaded orange capacitor disease". If that's the problem I'm surprised it doesn't seem to affect both channels (or I'm just old and deaf and can't tell).
Thanks in advance for any assistance.
I'm hoping someone can help me. I have a 31 year old Audionics BT-2 PreAmp. One channel is weak and sounds muddy. The other channel sounds great. I've verified that it is the BT-2 and not the CC-2 Amp.
The other problem is that when the tape switch is in the "Tape" monitor position there is "bleed-through" from any other component that is attached to the BT-2 and turned on -- in other words I can hear the tape but I can also hear another component bleeding through to the speakers.
I did open the case and reattached the volume and balance pots which were loose and turning such that the wires were wrapping around the pots. I didn't find any obvious broken wires or damaged solder joints on the pots. The pots seem to work as they should but the right channel is definitely weaker and muddy sounding. If the balance is mostly on the right channel, the volume does improve but it still sounds muddy compared to the left channel.
I did a bunch of searching on the internet and about the only thing I found of value was a mention of the "dreaded orange capacitor disease". If that's the problem I'm surprised it doesn't seem to affect both channels (or I'm just old and deaf and can't tell).
Thanks in advance for any assistance.
you need o clean every switch and every pot of the machine very very carefully and effectivelly
then you need to make sure that all electrolytics inside work also propelry ... nice option will be that all need to be both replaced or upgraded
then you need to make sure that all electrolytics inside work also propelry ... nice option will be that all need to be both replaced or upgraded
Thanks for the advice. Sorry for the delay in responding but I've been away.
I believe all of the pots are sealed, but I will pull them and see if I can carefully open them without destroying them in the process.
Thank you!
I believe all of the pots are sealed, but I will pull them and see if I can carefully open them without destroying them in the process.
Thank you!
I think that did it unless my ears are deceiving me!! There were a few small openings I could spray contact cleaner into, so I did it repeatedly and worked the pots repeatedly and it looks like success! Huge improvement!
With my magnifying glass I did notice two little orange capacitors that looked like they said "MP 47K 1KV" and they appeared to have gotten hot on the top because the coating looked a little melted. Maybe this is my slight crosstalk problem when listening to the tape monitor with other components on. I'm not too sure I'm up to changing the caps as it looks like a delicate operation to get the board out without damaging some delicate connections. Maybe I'll get bold some day. For now I'll just leave everything off except what I'm actually using.
Anyway, the right channel is now booming loud enough to make the wall shake and it sounds immensely better. Even the left channel seems to have improved.
Anyway, THANK YOU SO MUCH! If you were here I'd give you a huge hug!
I live on the Big Island of Hawaii and getting any electronics repaired here is next to impossible. I love my old Audionics components.
Aloha,
Cheryl
Be sure to clean the selector switch. Both sides with deoxit and a q tip. The bipolar caps on the inside of the black boxes also need replacement. Unfortunately the chose to encapsulate the rest
Sorry to take so long to respond. Have been going through medical issues.
I did fix it by cleaning all of the switches and making sure the balance and volume controls (which kept working loose) were well grounded. Even if you tighten the switches they don't always ground properly to the case. I also cleaned the grounds for the circuit board and all of the rca connectors. I replaced the tantalum caps (which were WAY out of spec). It is working flawlessly now.
Thanks to everyone for their help.
I did fix it by cleaning all of the switches and making sure the balance and volume controls (which kept working loose) were well grounded. Even if you tighten the switches they don't always ground properly to the case. I also cleaned the grounds for the circuit board and all of the rca connectors. I replaced the tantalum caps (which were WAY out of spec). It is working flawlessly now.
Thanks to everyone for their help.
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