Phono Preamp Tube Rush

An open mind and a test disc w spl meter :-)

I change something and if in a couple weeks i want to go to bed at night instead of listening, the change was bad.

dammmmmm audiophiles!!!!!. Please take this out of my mind.

I didn’t know about this, have never heard it, and now it is in my mind that I just haven’t been paying attention. I’ll listen tonight, better not hear anything.

I had my new dual arm tt CRANKED last night. 3 guitarists, Euryhmics, Michael Jackson Thriller, test record musical/imaging tracks, Stereo, Mono, ....

I heard some static between tracks, nothing else. I gotta get a fresh copy of that Eurythmics album, perhaps Valentine’s Day.

Fisher 80Z Mono Blocks; Fisher 500C; Fisher 800 (500c + am); now wonderful McIntosh mx110z (2 MM Phono inputs); My friends never push their system like I do, their speakers are not as efficient as mine, over 100db/1w/1m.
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Is this perhaps related to volume factors?

1. efficient speakers get loud before excess power needed by inefficient speakers, thus the ’rush’ doesn’t occur. Inefficient speakers get you into the 'rush' zone.

2. Low Output MC Cartridges, require more volume than MM cartridges that I use.

3. the combination of inefficient speakers and low output cartridges.

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@elliottbnewcombjr
The "rush" sound from your source components renders roughly the same on both efficient and inefficient speakers - because your efficient speakers are equally sensitive to both the noise to the signal (i.e. signal-to-noise ratio unaffected by speaker efficiency), and you simply set your volume control to the desired signal level (i.e. lower volume to compensate) - the ratio does not change.

With very low output MC cartridges you are reducing the signal without reducing your system’s noise floor (especially that before the volume control, i.e. phono stage), hence the issue - you have to raise the volume to hear same signal level, and thus you relatively amplify the phono stage’s noise level for the same signal level. The ratio gets worse as you go to lower output cartridges. Here is where SUTs can help - to raise your signal without raising noise (ground hums notwithstanding).

With very very efficient speakers as yours, you do have to become concerned about the inherent noise floor of your preamp and amp - i.e. the active gain stages AFTER the volume control. Especially the preamp, since its residual noise is un-attenuated, and amplified by the amp. Preamps that are dead quiet in normal systems may be quite noisy in yours! Generally you try to avoid high gain components with efficient speakers (mine Tannoys are an honest 96dB), but not all high gain components are equal - my ARC Ref 6 preamp has a demonstrably much lower noise floor than other tube preamps at roughly the same gain level (14 dB). It is dead quiet! Very impressive.

Thanks for clarifying.

I am fundamentally opposed to Moving Coil because of the extra amplification involved. I don't even want to hear a fabulous one, I don't want to go down that rabbit hole.

My Preamp, 55 years old, when direct to the integrated amp's bypass pre-in, then gets all volume from the preamp. In that use, I start to get noise, hum, around 11 o'clock position. It's just above my preferred max. so luckily I stay just below any noise.

I've hosed the internals with contact cleaner, no noises, but hum begins. I've tested my 17 tubes twice, but, to be sure, I ought to try some new ones before I spend some money switching caps .... Oh I'm keeping it, even if it needs spending some money.

Using my preamp into a line input, volume is created elsewhere, no hum from pre-amp even when system cranked. 

So, below my typically desired volume, in any configuration, this 55 year old pre-amp is noiseless. 

btw, The preamps FM Tuner, as they say: with a good signal, is superb.

the tube amp, Cayin AT-88, still sold, is dead quiet. Mine is early version with 16 ohm taps, sadly bias adjust is internal.
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Still never heard tube rush.
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btw, McIntosh does not service these, has no parts, and only referred me to 1 local service shop. He has a 12 week cycle for new work. Says he only needs 2-3 hrs work, probably not mush $ in parts. So, I say, put me in the schedule 4 months from now. No, I can't keep track like that. Bring it here, wait 12 weeks till I get to it.