Quietest amp you ever owned ?

A few years ago I had the little Antique Sound Labs MG SI 15 DT integrated and was impressed how quiet it was; in other words with the amp on and no music playing it was dead quiet when I put my ear right up to the drivers on the speaker. I am curious what other amps out there are as dead quiet since most amps have a slight hum or hiss that can be heard when music is not playing. At the time I was using Coincident Conquest speakers which are pretty efficient.
Spectron Digital One, a digital switching amp. I owned one to power my Maggie 1.6's, back in 1999. Dead quite with volume all the way down or up!
Still using my dead silent Dynaco ST-80 (by Panor 1996) with my conquests. Never heard such power and detail out of a 40 watt amp/20 watt triode.
Art Audio PX25. The most "black" background.
H20 Signature Monoblocks. No background noise what so ever.
A 1982 TRANS-NOVA TWIN 200 made by Acoustat; dead quiet at full volume. I don't use it anymore, but I still have it.
I have a Belles amp that is super quiet, it doesn't work.
The new TRL D-225 dual mono amp is the quietest I have ever heard. No hum or hiss whatsoever.
TRL ST-225 Integrated. Dead quiet, no hiss, no hum.

Incredibly fast and dynamic, too.


The degree to which an amp will be perceived as quiet or noisy depends to a certain extent upon how efficient (or inefficient) the speakers it is used with are, e.g, a 92 db/watt efficient speaker will make upstream components sound noisier than an 86 db/watt efficient speaker. In fact, the noise level with highly efficient speakers, like horns or many single-driver speakers, can be intolerable unless partnering components are chosen with an eye toward their noise characteristics.
Innersound ESL 300. It's just dead quiet.

Yamaha M-80

SNR -127dB
Elevick I never knew the Dynaco ST-80 was that quiet; I had a ST-120 way back in the early 70s. The reason I am asking this question is that I am running a pair of modified Klipsch KLF-20s in a second system and, as Raqual has pointed out, the more efficient the speaker the more the amplifier noise comes through. Speaking of Dynaco I had a ST-70 at one time with the Sutherland front end board and it was dead quiet; on the other hand the stock amp with the 7199s was pretty noisy. Thanks everyone for your input; I've learned a great deal.
Yamaha MX1000U
(1979 - solid state, 760wpc @ 4ohm; 960wpc @2ohm; 460wpc @8ohm) which I still use with fabulous results. I am amazed that for the power output and the cheesy original power cord that this monster does not put out ANY noise. Totally clean.
Even my CR-1020 (1978 - 90wpc @4ohm; 70wpc @ 8ohm) which is in a separate system performs in the same quiet manner.
A while ago I sold my much newer Mac and a Krell but kept the Yamahas. Do it again Yamaha ... where'd you go.
The 80 can't be compared to anything Dynaco originally produced. I've played with 70's and even had a pair of fully restored/upgraded MKIV's. Nothing can touch this amp. Panor+25 years of technology really made a difference.
The re-release of the 70 should be quite nice also. Finally, I do believe there is a 160 out there.
Elevick I'll have to try to pick up one of those 80s.
My nomination is a tossup between the Tom Evans Linear A and the Wavelength Triton. Both are quieter than any of the SS amps I've owned - so quiet that with my ear inside the 97dB speaker cones I can't tell if they're running. This is with the Tom Evans Vibe line stage, because all the other preamps I have except for a TVC add way more noise than either of these amplifiers.

Noise on the Wavelengths was measured during construction at .12 mV or 120 microvolts... Both are super-quiet, but the Linear A manages to put more music in front of that black background - but that's a topic for another thread.
I just changed over to balanced cables on my Spectron Digital One and it is absolutely dead quiet all the way to maximum setting on the volume control. But once fed a signal, the dynamics are unbelievable! (I also use Rothwell Electronics line attenuators on the input and Spectron's own Zobel networks on the speaker posts).
Singlepower Audio SDS-XLR tube headphone amp. Even through the most sensitive headphones with volume up all the way....Not a peep.
Red Wine Audio Signature 30.
I've heard the Red Wine Audio Signature 30 and have to agree it is extremely quiet. Want to get the newest version of the Antique Sound Labs KT88 single-ended tube amp with remote.
Both my Edge NL12.1 and my Pass X350 were completely silent (but the Pass was HOT HOT HOT; The Edge is barely warm).