Will Changing my 100 Watt Tube Amp to a 200 Watt SS Amp Solve My Problem?

John, Is the adjustibility of gain is the LS25 applied after the source but before the volume control and line stage amplification (tubes).  It did on my ARC Pre (a different model). The blurb I read on this pre-amp talked about the ability to reduce source gain in the context of matching gain of multiple sources. I didn't see anything about reducing pre-amp output gain. Typically you can only change pre-amp output gain either by internal implementation of a resistor or by adding an aftermarket fixed attenuator.

 If so, then any tube noise (or any other noise for that matter) would be passed on to the amp full strength. Since Mark's noise increases as he rotates his volume attenuator, the cause of the noise  increase must originate in the pre-amps circuitry before the amplification stage or in the source, which IMHO would more likely be the phono stage which are notoriously noisy. With a phono stage the noise could originate with the design itself, of if it uses tubes, then the tubes might not be low noise enough. It could also be the phono cartridge itself. 

Mark, I haven't read the preceding posts.  I'm sure Al or someone else have already mentioned this to you. But, I would point out that the difference between 100wts and 200 wts is only 3db, i.e. not very noticible. Now if your speakers require an amp with high(er) current (i.e. they have a impedence curve dropping to 4ohms or less) this could be an exception. But even if your amp could produce 800wts at  2 ohms you still would not be solving any noise issues caused by your pre-amp's amplifications stage.

FWIW. Forgive any redundancy created by existence of preceding posts.

Does it have a quiet phono stage? Or you could buy a gun. Personally, I I had to go solid state I think I'd choose the latter! :-)

Sorry, another question.Have you disconnected all of your sources from your pre-amp, in fact unplugging them is best, and then rotate your volume control to its 3 o'clockposition and see if you still have the noise? Rotate to max, any noise then? If the answer happens to be 'no noise' then add your sources back, one at a time until you find the one which starts the noise as previously described.

 If the answer is there was no change from your fully connected system then you have either found the noise floor of you pre-amp or that you have something in the circuitry in the pre-amp prior to the amplification stage which is causing it. You might then contact ARC and ask their service department techie.

Mark, Maybe a dumb question, but exactly where are you when you can first hear the noise? When you are in your listening chair? 6' from your speakers? 6" from your speakers? I know some folks, of the anal sort, like me perhaps, who put their ear right up to the tweeter and judge by this. Does this noise really intrude on the allusion of a black background when music is playing? Is the background noise a hiss or a hum?

Mark, I don't know how assessible the folks at Whest are but my next move would be to contact their service department or technician and set out the issues to them and see what response you draw, if any. 

Mark, What this says to me is that your issue is with the noise floor of your phono stage. With the cartridge (TT) disconnected from the phono stage the noise you are hearing is inherrent with the design or the mechanical condition of the phono stage.

 This really has nothing to do with, in an absolute sense, the gain issues. You can lower or raise the gain but this will not remove the noise issue. If you lower the gain from the phono stage but compensate by increasing the signal level with the volume control you have a net zero change. If the noise is a substantial issue for you after you have adjusted all of the gain possibilities you need to reconsider your use of this phono stage. 

BTW, FWIW, I really appreciate those folks who can rise above the obvious implications of my 'handle'. Says much more about them than me
I think. 

Hi Mark, It appears that you have sourced your problem correctly to your phono stage and/or cartridge. To determine whether its is the phono stage or the cartridge or both in combination, disconnect the IC from your TT to the phono stage and just listen to the phono stage at various gain levels and with your pre-amp VC . If there is no noise (as I suspect there will not be) then you have either a mismatch with the cartridge due to the inherent noise floor of the cartridge, something mechanically deficient in the cartridge or its set up. I'm not familiar with your phono stage or cartridge so I can't help you on this issue.

I'll save your eyes a bit by not amplifying on these comments but I would be happy to explain my conclusions if you ask.
1) There is nothing wrong with your pre-amp.
 2) There is nothing wrong mechanically speaking with its tubes.
 3) There is nothing wrong with having to listen with your volume control at 3 o'clock or even wide open if that is the position that meets your needs. Remember, all a volume control does in your pre-amp is lower the strength of the signal from the source before it reaches your volume control.. That's all. It does not lower the strength of the output from the pre-amp's tube section which is seen at a constant level by your amp.To some degree its function is redundant to the other options your have to reduce source output strength.

BTW, re the hum on the unconnected CD input selection. Small hums can be very difficult to trace. But before you conclude that this is a problem try connecting your dac to this input and see if the hum goes away.

Hope this helps a bit. Perhaps others can comment on your phono stage/cartridge/set up issues. 

Mark, I forgot to mention, be careful thinking about the wonders of a tube phono stage, ARC or not. The sonics are quite often great but noise, not so much. When I think about tubed phone stages I always think of high output MC cartridges. Low output MC's can be a real challenge. I used to have a love affair with Benz cartridges but that was quite a few years ago.