Marantz 7c Question - HELP !

[cydest]

Hi, while manipulating (blind) my Marantz 7c, I inadvertently used shorting plugs on the output RCAs. Of course no sound (nada) coming out of the 8b. I first thought my CD player was out. It took me a few minutes until I realized my mistake.

Your first reaction: what an idiot ! Well, I have to agree...

Your second reaction: please re-assure me that no damages to the 7c or 8b occurred (the set still sounds good).

- What could be theoretically damaged?
- Which components should I check?
- being a short-circuit, why did the fuse did not blew up?

Any inputs would be highly appreciated, and yes you can make fun of me on the forum !

thanks !

 

[jstang]

No issue for either one....

The fuse would not blow because output tubes would limit the current. The vast majority of the power is used for the heaters.

Many inputs for the preamp short themselves when deselected. So... Many low power outputs like the output stage of the 7c are shorted all the time.

For example, the 10b tuner uses the same 12ax7 for its output and when not selected...they are shorted by the selector knob of the 7c without any damage.

Johnk

 

[cydest]

Thank you very much !

 

[goatster]

agree 100 % with johnK . NOt a problem at all

In general, I use shorting plugs for all high impedance inputs on my preamp -- phono, mic, tape head. Lower impedance inputs not so crucial in my opinion

 

[jstang]

Actually the 7c does not short inputs.... The 7t does short the inputs to ground that are not sellected. The grounding takes place via the selector switch.

Obviously the input that is selected is not shorted.

Point is that for many years Marantz sold the 10b with the 7t and the 7t would short the 12ax7 output tubes with no negative affect.

So, don't worrier be happy...

Johnk

 

[cydest]

Your answers are really appreciated. Will finally return to deep sleep !