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Phono input on amp

Q

Quimbly

Guest
Hey all,
My amp doesn't have enough inputs. It's old model, probably from the late-70s to early-80s. It has two "Tape" inputs, and "Aux" input, and a "Phono" input.

Currently, I have my tape deck hooked to the Tape1 input, my CD player to Tape2, and my computer to Aux. However, that leaves my TV and DVD/VCR not attached to my system.

We generally don't watch TV, and usually only watch movies originating from my PC. But there are times when the lousy speakers on the TV are annoying, so that I'd like to hook my TV up aswell.

What potential problems can I run into by hooking my TV (or any of the other audio sources) to the Phono input of the amp?

Thanks!
 
Q

Quimbly

Guest
Yes, but why?

What would happen if I plugged in something other than a turntable?
 

Zacabeb

Active Member
Other possible differences aside, the phono input is designed for much lower levels than a line input, and passes the signal through a RIAA equalizing stage. Connecting anything else than a turntable would violently distort the sound and amplify it to a level way above normal level. It could also possibly cause damage to the circuits, and possibly other components including the speakers.

Addition: I made a test with my old amplifier and my old headphones, both which I considered "expendable". The result was that the sound was extremely distorted, and somewhere around 40dB (!!!) louder than via the CD input. The sound came actually came through in spite of the fact that the volume was turned all the way down.

So, in a nutshell, it is not at all possible to use the phono input for a line level signal, unless you use a line-level-to-phono-level converter. The mere attempt to connect a line level source directly to the phono input may damage your system and will not result in anywhere near acceptable sound. I advice against even trying it, as that alone may result in damage to your system.
 

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