Hi,

I have found that when I connect my tv (JVC-HV28P37S) via the phono output to my amplifier the TV sound (from the TV not the amp+speakers) can get muted and tinny - loss of volume and bass. The amp is off at the time.

The TV sound is fine provided I have the amp input switched to whatever I used for the TV (in this case the AUX), but if I change the amp's switch to, say, TUNER or TAPE the TV loses sound quality. This is with the amp off (or on - doesn't matter).

Its like the amp swallows the power unless connected to the TVs input.

I find this odd - I'm sure it didn't use to do it. Can anyone offer an explanation?

Thanks
J

[NST]

The only thing I can think of is that your amp is grounding the incoming signal when you're using a different input, for example Tape or CD. Some amps do this to prevent crosstalk in the other channels, but in your case it might have a knock-on effect on the TV's amplification.
Just out of interest, what make and model is your amp, and how old is it?

Hi NST,

Thanks for your reply and I'm sorry for the delay in getting back to you - couldn't get logged in again and when I reset the password I got nothing from the forum - just discovered the emails were being blocked as spam!

I think you are right - the amp is prob grounding the connection and it affects the TV. Not sure why this is happenning but the amp is old and it does have an earth hum from time to time so I think its time to look for a new one. The amp is a JVC AX2 I think - dates from about 1980 and had an impressive 2xTAPE, 1xAUX, 1xTUNER, 1xPHONO when I bought it!

I think I am right when I say it always did this sort of thing when the phono was selected, but I've not come across it with the other inputs. I should prob track down the hum - but I'm no expert in this and I need more connections these day, so sad as it may be to discard the worthy beast I think it may be the best solution.

I was worried it was the TV (coming up to the year and I thought I'd have to act quick before they get funny about the guarantee) but prob not.

Cheers
J

[NST]

Hi Jonathan,

Yes I thought it might be an old amp. Try selling it on eBay, there's normally quite a bit of interest when it comes to old amplifiers and receivers.
As for new amps, they tend not to ground incoming signals, as the switching and isolation is much better. I know that my Sony QS amplifier (TA-FB940R) uses a relay to connect each source when it's selected, thus removing the problem of stray signals actually entering the amp in the first place.

>Try selling it on eBay, there's normally quite a bit of interest when it comes to old
>amplifiers and receivers.

That's a good idea - I even have the original box and instructions and it would be nice to think someone might try to fix the intermittant hum and carry on using it.

Many thanks
J