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Phono Preamp Tube Rush

Is there such a thing as a tube phono stage that doesn't have tube rush? Is it just an inherent weakness of that type of pre or is it some combination of cartridge gain and preamp gain? I went from a silent solid state ASR Basis Exclusive to a Herron VTPH-2A (new home with space limitations) and now I'm using a Hagerman Trumpet with my Decca London Super Gold. Both the Herron and Hagerman have tube rush. The Hagerman beats the Herron in my setup and it really sounds incredible but in quiet passages and between songs, there's that hiss at high-medium and high volume. It's just there. No combination of new tubes, new cables, etc changes this fact. Same with the Herron. Anyone having a different experience with a tube phono preamp?
dhcod
three_easy_payments's avatar
three_easy_payments
2,097 posts
 
@lewm 

I appreciate the detailed explanation!  I was unaware of the Manley hybrid design.
dhcod OP
706 posts
 
Interestingly, changing from my Herron VTSP-1/166 to a Lamm LL2.1 made a big difference, and not because the Lamm itself is quieter because it isn't. Could it be something with input impedance?
hagtech
173 posts
 
It’s all relative. There will always be phonostage hiss, whether tube or solid state. The goal is to get it quiet enough such that it is lower than silent groove noise. How much SNR is enough?

I just tested my system (Piccolo2 - Cornet3 - Tuba) at full volume into an HP400 AC meter. The difference between a silent groove (my best is the Hi-Fi News Analog Test LP) and the tonearm up is 9dB. Perhaps not numerically impressive, but it’s like night and day listening-wise. The uncorrelated groove noise sounds way louder.

Forgot to mention, this is with a Dynavector 20XL MC cart (0.3mV) into 100 ohm loading...
tobes's avatar
tobes
436 posts
 
All tube phono with low output MC is probably impossible to get really low noise.
Low gain tube phono + SUT has been what I've used for the past 8 years. 
Cary PH302 has low 38dB MM stage and I'm currently using with Cinemag 1131 on 26dB (1:20) setting. I'm using vintage NOS tubes. Super quiet and dynamic with the Denon 103R.
hagtech
173 posts
 
SUT is the easiest way to get low noise input.  Works very well. 

I'm thinking all-tube may be possible using a pentode into a load of 10k or less.  Then again, microphonics will become the new problem... 
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