Preamp Headroom Question

Ralph, sorry to sound dumb, but not sure what you mean when you say "how much noise there is when the needle is in a good silent groove." Does that imply when the record is spinning??

I ask because I checked the phono noise level with the linestage set to 80 clicks (out of 104) with the TT motor running, but with the tone arm lifted OFF the record. Is there noise?? Yes. I can hear hissing about 2 foot away from the speakers. The noise level is about the same out of both channels. Much beyond 2 feet, it's pretty quiet, or quiet enough.

My linestage is pretty quiet, about -109 db; the phono pre is fair, about -74 db, but not outrageous for a tube phono pre.

I'm not sure how to assess noise if the stylus is in a "quiet groove" while the record is spinning. If you are referring to a quiet passage, like a single instrument playing (e.g., a flute or violin), I don't think it's too bad. If anything, on some records, I'm probably hearing the stylus tracing the groove. On other records, very little groove noise.

Having grown up in the 70s, vinyl was notoriously "hissy." OTOH, I just bought a brand new 200 gram Mahler LP re-issue from Acoustic Sounds. It's very quiet.

Not sure all of this is responsive to the comments and suggestions offerred by you and Al. But that's all there is to report.

My main Q was about dynamic headroom if I crank the linestage up. Per Al, shouldn't be a problem. If it is, it's likely happening on classical records which generally present large dynamic swings in volume. Less so on compressed rock.

Thanks

BIF

Ralph, I'm not sure I understand your comment either, especially the part about "in the latter case the noise should be less than that of the groove." Can you clarify? Did you mean "in the former case"?

Also, why would playing an essentially silent groove say anything more about the noise performance of the phono stage than an assessment that is made with the stylus lifted off of the record?

Best regards,
-- Al

My main Q was about dynamic headroom if I crank the linestage up. Per Al, shouldn't be a problem. If it is, it's likely happening on classical records which generally present large dynamic swings in volume. Less so on compressed rock

How you word your question suggests that you are thinking in terms of how an amplifier is set up. Specifically amps are almost always set up to achieve full output before you run out of volume control, anything farther causes overload/distortion. Preamps on the other hand are typically set so that as long as you do not overload the input you will not reach full output (before overload/distortion) even with the volume control all the way up.

IOW, in properly set up preamp/amp set up you never drive the preamp into overload and distortion no matter how much you open up the volume control. The overload is in the amp.

This is why the other posts are discussing noise levels/issues as that is the major concern when having to turn the volume control up all or nearly all of the way.

HTH

Ralph, I'm not sure I understand your comment either, especially the part about "in the latter case the noise should be less than that of the groove." Can you clarify? Did you mean "in the former case"?

Also, why would playing an essentially silent groove say anything more about the noise performance of the phono stage than an assessment that is made with the stylus lifted off of the record?

In most cases the noise floor of the LP is going to be higher than that of the phono stage. Since the noise of the phono section will be masked by the LP surface, it is only important for the phono section to be quieter than the LP. That is why lifting the needle off the spinning LP surface really isn't telling you much.

Now if the phono section proves to be the noise you hear when you set the needle down in the spinning groove, that is when you know you have a problem.

Silent grooves can be found at the beginning of LPs, and also between cuts.

Thanks Ralph. Yes, that makes sense.

Best regards,
-- Al