Major Mark 2c+ Mistake

[Boogie-fever]

Without looking, I plugged a cable that was connected to my 2C+'s preamp out, into the amp's speaker jack...
Major blunder, because now the amp puts out very little volume with a speaker plugged in.
Any educated guesses as to what components I screwed up, and what it may take to repair this amp?

 

[glguitarman]

Ummm, could be very bad...

 

[McBarry]

Tricky call with the info given..
Was a signal running through the preamp out at the time? How loud was the signal ?
Was a speaker connected to the OTHER speaker jack all throughout this time?

Are U able to work inside a live chassis, or just looking for ideas before sending to the hospital?

Re what to troubleshoot, after a quick look at PSU voltages (inc bias), I'd go O/T, then V2 or wherever the preamp out derrives from, because you've possibly injected a signal INTO there, and possibly a huge signal at that..

Obviously, check/swap tubes..

Let us know, as many could learn from your unfortunate mistake.

Lastly, MB are bloody robust.. Take heart..
DB

 

[stokes]

I would think the most likely failure would be V2.

 

[NunoVanBamSteen]

I did something similar, plugged a cable intended for fx send into speaker out, ended up blowing the input of the delay I was using and the output transformer of my Boogie. The O.T. Ended up costing about 30-35 bucks delivered and I replaced it. That and a handful of JRC4553 drivers for my delay and back in action.

See about nabbing a schematic of your amp and if you need help deciphering it, post it here and we will see what went bad. My guess would be the output transformer, as there are multiple taps on it and you probably fed some voltage that the preamp out isn't used to seeing.

 

[Boogie-fever]

At the time, I was planning to send the 2c+'s, preamp signal to the power amp of a 2B, Coliseum Series. However, I began A-B-ing both amps and they sounded remarkably similar. Without looking, and thinking that i was holding a speaker cable, I plugged the 2c+'s preamp out, into its own speaker jack. I proceeded to disengage the standby switch, and the volume was only up around bedroom levels.
Subsequently something had fried out, and the amp had very little output volume...
Meanwhile, I was asking around about the amp, yet I couldn't properly trouble shoot it...
Completely embarrassed, I brought it to Boogie, in Petaluma. I was told it was probably the tubes, and I was given the option of leaving the amp there... Deciding to bring the amp home, I changed out the tubes. This didn't solve the problem, so I tried a different set of tubes. By then, a connector from the tube socket had broken off and was still left collared on one of the 6L6, tubes' prongs, when I removed the tube.
At this point I needed pro help and eventually brought the amp back to Boogie.
I received a call yesterday letting me know that my 2c+, had been repaired.
Ultimately, the original problem was that a tiny transistor needed replacing.
The tube socket was reconfigured to work properly.
The job only cost me $75,
and I am happy!
I'd like to thank every one that responded to my original post.
It's great to finally have some conclusive closure.

 

[soundguruman]

Without looking, I plugged a cable that was connected to my 2C+'s preamp out, into the amp's speaker jack...
Major blunder, because now the amp puts out very little volume with a speaker plugged in.
Any educated guesses as to what components I screwed up, and what it may take to repair this amp?

Possible blown output transformer.

 

[stokes]

Without looking, I plugged a cable that was connected to my 2C+'s preamp out, into the amp's speaker jack...
Major blunder, because now the amp puts out very little volume with a speaker plugged in.
Any educated guesses as to what components I screwed up, and what it may take to repair this amp?

Possible blown output transformer.

Not even close,stop skimming.

 

[Henz]

At the time, I was planning to send the 2c+'s, preamp signal to the power amp of a 2B, Coliseum Series. However, I began A-B-ing both amps and they sounded remarkably similar. Without looking, and thinking that i was holding a speaker cable, I plugged the 2c+'s preamp out, into its own speaker jack. I proceeded to disengage the standby switch, and the volume was only up around bedroom levels.
Subsequently something had fried out, and the amp had very little output volume...
Meanwhile, I was asking around about the amp, yet I couldn't properly trouble shoot it...
Completely embarrassed, I brought it to Boogie, in Petaluma. I was told it was probably the tubes, and I was given the option of leaving the amp there... Deciding to bring the amp home, I changed out the tubes. This didn't solve the problem, so I tried a different set of tubes. By then, a connector from the tube socket had broken off and was still left collared on one of the 6L6, tubes' prongs, when I removed the tube.
At this point I needed pro help and eventually brought the amp back to Boogie.
I received a call yesterday letting me know that my 2c+, had been repaired.
Ultimately, the original problem was that a tiny transistor needed replacing.
The tube socket was reconfigured to work properly.
The job only cost me $75,
and I am happy!
I'd like to thank every one that responded to my original post.
It's great to finally have some conclusive closure.

Old post but I wish repair techs there would tell you/ us exactly what part failed. Instead of just a tiny resistor failed.