Phono Preamp Tube Rush

Harry, you did not read the thread carefully enough. I mentioned them way in the beginning.

Mike

If Johnson noise is a problem you can narrow the bandwidth of your cartridge to 100 Hz (stick chewing gum behind the cantilever I guess)
or dunk your cartridge in liquid nitrogen before you play a side:) 
Seriously, this is all academic because there is not a darn thing (reasonably) that you can do about it and I hate math.

Lewm, according to the meter I have yes with peaks just slightly over 110 dB. (I had ear protection on at the time:) God knows how accurate the meter is. I think more remarkable is that this is with ESLs (using subwoofers from 125 Hz down). From 10 row center the last NIN concert I went to hit 120 dB (I also had hearing protection on) Getting the meter into the concert was a bit rough. Had to take the battery cover off and show that it was working while everyone behind was getting pissed. Anyway, the loudest I ever play it on rare occasions is 105 dB usually with concert videos. Most of my listening with Rock and Jazz is at 95 dB. Don't forget to warm up your ears first! 
I love your Steelhead, almost bought one but right now I am looking at Phono amps with balanced outputs and inputs. Coming from where Manley does you would think they would do that. 
We live in a house I have been building since 1993. 
In regard to the SLN tubes the only thing I can say is that with the system set at 95 db I can not here anything with my ear right against the speaker over the background noise of the house. With the volume maxed out I can just make out a hum, again ear against the speaker. The Tubes are now 6 years old. I have no idea if this is noisier than when they were new but even if they do get noisier with age I suspect a SLN tube will always be quieter than a LN or standard tube of the same age and make.

Yes Ralph you are correct usually j fets I think and I do believe it is to reduce noise. My next phono amp Is going to be balanced. Can't wait to try that. I would like just a little more gain for ultra low output cartridges and I believe from what I have read that a balance design should have lower noise levels. Cartridges are balanced to begin with.

dhcod, It would take a severely defective tube to cause a 25% decrease in sound quality. I have not used a 12AX7 unit since 1965 and a Dyna PAS 3X but with 6922's the only significant difference between tubes is noise which is much easier to quantify than sound quality. Whatever differences there are in sound quality are marginal at best but having all kinds of crap going on in the background of quiet passages is annoying. I suppose if you only listen to Metal it does not make a difference and besides the tube with those gold pins must sound better. 

I have never heard an ARC phonoamp with "tube rush." They do have noise way down which is not a factor up to 110 dB in my system. I do use super low noise 6922's from Roger Modjeski's tubeaudiostore.com. He measures every single tube and puts them into three categories, standard, low noise and super low noise. The super low noise tubes are said to be one in 100 tubes tested. I have purchased 6 tubes and they are all obviously quieter than the ones ARC supplies. From my experience NOS tubes are a rip off. I had NOS Telefunken 6922s and they were no where close to Roger's tubes as far as noise is concerned. With Roger you know exactly what you are getting which is very reassuring. If your phono amp is noisy with super low noise tubes then it is either defective or a bad design.