Rotel Preamp Phone Stage - Major Noise

[tonym]

Hello. I have a Rotel 1070 preamp on a Carver amp. Never had a Turntable on this system until I received one as a present this Christmas. A vintage Phillips 312 with an Ortofon 5E mm cartridge. With the phono connected (properly grounded), if I switch the preamp to the phono stage I get a very high level of static and noise. Grounding has been checked and rechecked and it is fine. This Turntable was hooked into another system and presented no noise. Replaced the TT ground wire and tweaked the tone arm and alignment. So the issue seems to be with the Rotel phono preamp stage.

Any advice? Should I get a separate phono preamp and hook it through the aux input? Or should I just dump the Rotel and get a new preamp with a less sensitive phono stage? I am committed to moving back into vinyl with this system configuration or with a new one. But I am not sure how to proceed.

 

[docvale]

is the noise decreasing/increasing with the volume control?

 

[tonym]

is the noise decreasing/increasing with the volume control?

Hi. The noise increases with increased volume control and vice-versa. Tonal quality of the record playback is actually quite good and denser sound passages will drown out the noise. But noise always comes forward in quiet passages and between tracks. I'd say that, roughly, it's a 1-to-10 ratio -- where if the volume was at 10, the noise would be at 1 (without music).

 

[docvale]

If you are happy with the Rotel pre, the most logical option would then be getting an external phonostage and enter into a line input.
Fixing the internal phono of your pre, even if doable, might be costier.

 

[Solypsa]

Just for kicks remove the signal cables coming from the turntable to the phono input and all others. Then flip through inputs ( carefully raising volume as needed ) and listen to the audible background noise levels between the inputs. Any notable differences? Phono input will always have more gain but this is looking for major issues.

Next, with TT cables re-attached ( but without a record playing ) , select phono input and carefully raise volume till self noise is audible. Now touch the tonearm, and the rca jacks ( if metal ), and various points on the 312. Anything change in the noise?

Anyways if you go with a new, external phono preamp take a look at Hagerman Audio. Made in Hawaii, by a designer that is very experienced with high-value phono preamps. The Bugle3 is $199.

There are lots of good full function preamps with decent phono sections that can be had used too...

This is a good time to ask yourself if you are likely to be upgrading pieces...not saying you need to spend a ton but best to make lasting buys.

 

[tonym]

If you are happy with the Rotel pre, the most logical option would then be getting an external phonostage and enter into a line input.
Fixing the internal phono of your pre, even if doable, might be costier.

Agreed. I'm now on the lookout for a good phono pre in the ~$200 range.

 

[tonym]

Just for kicks remove the signal cables coming from the turntable to the phono input and all others. Then flip through inputs ( carefully raising volume as needed ) and listen to the audible background noise levels between the inputs. Any notable differences? Phono input will always have more gain but this is looking for major issues.

Next, with TT cables re-attached ( but without a record playing ) , select phono input and carefully raise volume till self noise is audible. Now touch the tonearm, and the rca jacks ( if metal ), and various points on the 312. Anything change in the noise?

Anyways if you go with a new, external phono preamp take a look at Hagerman Audio. Made in Hawaii, by a designer that is very experienced with high-value phono preamps. The Bugle3 is $199.

There are lots of good full function preamps with decent phono sections that can be had used too...

This is a good time to ask yourself if you are likely to be upgrading pieces...not saying you need to spend a ton but best to make lasting buys.

With the phono cables unplugged, i get some noise from the phono stage and zero noise from the other stages. With the preamp set to phono, and the volume up a bit, as soon as I plug in the phono cables the noise increases 10x. And still zero noise on the other channels. Touching the tone arm makes no difference. I'm afraid it's the Rotel phono stage. So now I'm looking for a good phono preamp in the $200 range. I'll check out the Bugle3. Thanks!

 

[tonym]

Hello. I have a Rotel 1070 preamp on a Carver amp. Never had a Turntable on this system until I received one as a present this Christmas. A vintage Phillips 312 with an Ortofon 5E mm cartridge. With the phono connected (properly grounded), if I switch the preamp to the phono stage I get a very high level of static and noise. Grounding has been checked and rechecked and it is fine. This Turntable was hooked into another system and presented no noise. Replaced the TT ground wire and tweaked the tone arm and alignment. So the issue seems to be with the Rotel phono preamp stage.

Any advice? Should I get a separate phono preamp and hook it through the aux input? Or should I just dump the Rotel and get a new preamp with a less sensitive phono stage? I am committed to moving back into vinyl with this system configuration or with a new one. But I am not sure how to proceed.

UPDATE:
This fix may be of use to others.

So, I was having no real luck reducing my phono preamp stage noise down to a tolerable level. I tried lots of fixes, including trying to ignore it, but it was really ruining my record listening. Finally, in response to a post like this one on another bb, someone made a suggestion that was a direct hit.

They said that it might be related to my wifi system, specifically if we had a plug-in wifi extender system hooked in at our house. We did. These range boosters plug into your wall and use the house wiring to extend the range throughout bigger houses. We require this so that my son has decent reception upstairs for his work and, more importantly to him, his gaming.

We disconnected the range extender as an experiment and my phono noise disappeared -- 100%. Buuut, no wifi upstairs.
Talked to a tech nerd friend who told me to try an alternative to the plug-in house wiring solution: it's called Moca. It uses the house coax wiring instead of electrical wiring. The house cable/coax runs into most rooms, including my son's, so this was viable. We bought it, installed it, and —magically— it worked.

Nomo phono noise, better wifi coverage than before, and my vinyl is now in play once again.