PV-5 and MV-52 Combo

[BillyB]

Hi guys.....

I have a PV-5 which I love and an MV-52 which I really like as well.

I though they would make a great combo.......and they do tonally.......but they are noisy when paired together.

I thought being of the same vintage they would make a proper combo.....

But I have found that they sound better when combined with other non CJ gear. Go figure....

I think that they both might be a little noisy which when separate is not a big deal......but when combined the noise comes through.

I have tried new tubes in both. Its really difficult to determine which is the culprit since when I separate them.....the noise level drops a lot.

Are they a mismatch??

[admin]

Are you sure you not getting something like a ground loop? Have you tried changing the plug orientation, putting a ground loop isolator between the two components? It's hard to explain why either one alone would not be "noisy" with other components but together introduce noise.

[BillyB]

I have not tried a ground loop isolator......

I agree its a strange issue. It almost seems like when the PV-5 and MV-52 the gain is a little too high and so the noise floor is raised.

I need to point out that when separated neither are dead quiet......but they are not noisy either. The noise floor is lowered dramatically.

[rthomeint]

How old are the tubes? That would be the first thing I would check.

[BillyB]

New tubes

[admin]

You may want to try rolling the tubes and see if the noise floor changes. If it does, it may still be related to the tubes. Sometimes a new tube will be bad.

I would also try a ground loop isolator, you can buy a cheap one. I would never use it in my system permanently because I find it significantly decreases sound quality, but it's a good diagnostic tool to have.

[BillyB]

I think I narrowed it down to the Phono Stage in my PV-5......

What are my options......

?

[jeffreybehr]

I think I narrowed it down to the Phono Stage in my PV-5......

Billy, if the fono stage is creating the excess noise, that noise will decrease to virtually zero with the volume control full down, because the VC follows the fono stage, thereby reducing its level of music AND noise. If the VC being full down does not reduce this excess noise, the noise is originating in the line section, and its noise is not decreased by the VC because the VC is between the fono and line sections.

The PV5's line stage has high gain--28dB IIRC--compared with modern linestage preamps. Try to mix the '5s fonostage (using its Record Out) with a lower-gain linestage preamp to see if that reduces system noise.