Phono stage noise

excollier

Tricky question here.
I am using gear I bought new back in 1980. The amplifier is a Panasonic SU-2800.
My problem is noise on it's phono stage, like a buzzing along with a regular "ticking" sound.
I have an Aiwa turntable which also has a built in switchable phono stage, but it was switched off as the amp has it's own phono stage. This noise has been there ever since I replaced the original Panasonic turntable that died a few years ago. This noise is very noticeable and gets louder after an lp has been played.
Last weekend I bought a Rega Planar 1 turntable (I have been promising myself a quality turntable for ages). This also produces the noise but not as loud.
To try to run a check, I plugged the Aiwa tt into a spare line input and switched on it's phono stage - there is the noise again, via a different input ( all other inputs are normally noise free) so I'm guessing - no hoping - that this noise is down to a noisy mains supply and that phono stages are sensitive to it and pick it up. No other inputs or peripherals produce this noise.
One other thing, if I touch the pivot joint at the end of the tonearm on the Rega the noise gets louder until I remove my finger, even with the turntable powered off.
I have tried other power outlets too, but no difference, and the mains leads are away from any rca/phono leads.
Any thoughts and tips on this would be helpful.

edit: with the turntable unplugged from the amp inputs the noise changes, more of a very quiet "white noise" than a buzzing, and no "ticking". Perhaps a grounding issue as both turntables have no ground wire, where the original Panasonic tt did have one and was noise free.

akaSol

excollier wrote: »

Tricky question here.
I am using gear I bought new back in 1980. The amplifier is a Panasonic SU-2800.
My problem is noise on it's phono stage, like a buzzing along with a regular "ticking" sound.
I have an Aiwa turntable which also has a built in switchable phono stage, but it was switched off as the amp has it's own phono stage. This noise has been there ever since I replaced the original Panasonic turntable that died a few years ago. This noise is very noticeable and gets louder after an lp has been played.
Last weekend I bought a Rega Planar 1 turntable (I have been promising myself a quality turntable for ages). This also produces the noise but not as loud.
To try to run a check, I plugged the Aiwa tt into a spare line input and switched on it's phono stage - there is the noise again, via a different input ( all other inputs are normally noise free) so I'm guessing - no hoping - that this noise is down to a noisy mains supply and that phono stages are sensitive to it and pick it up. No other inputs or peripherals produce this noise.
One other thing, if I touch the pivot joint at the end of the tonearm on the Rega the noise gets louder until I remove my finger, even with the turntable powered off.
I have tried other power outlets too, but no difference, and the mains leads are away from any rca/phono leads.
Any thoughts and tips on this would be helpful.

edit: with the turntable unplugged from the amp inputs the noise changes, more of a very quiet "white noise" than a buzzing, and no "ticking". Perhaps a grounding issue as both turntables have no ground wire, where the original Panasonic tt did have one and was noise free.

Rega turntables are made to work without a ground, which is both a good and bad thing.
That aside, yes it sounds like you have a ground issue / over sensitive phono stage in your amp. The next obvious question is how much will it cost to fix and how much is a new amp?
A repair €100/150 while a new amp would be €200 (approx), obviously not what you want to hear after spending €300 on a turn table.
The last (and most drastic) option is opening the Panasonic and seeing if you can remove the phono stage (sometimes its just a small board attached to the main board) and then purchase an exterior one.

excollier

The same noise is produced from my other turntable, with it's built in phono stage, via the tape 2 inputs, so I'm really focussed in on it being a grounding issue with the amp - it just doesn't like a tt that isn't grounded to it's own dedicated ground terminal it seems......oh well.
I'm wondering if an external phono stage via the tape 2 inputs would cure this?

excollier

another idea

http://www.aqvox.de/REGA_250_300_Tonearm-mod-humm-free-remove-signal-groundrega_mod.html