I need a quiet tube amp

The Quicksilver Horn Monos are indeed quiet, but see if you can try them out first. I found them to be less musical than their other offerings. I've owned the Mini Monos, and heard the Mid Monos with 90db speakers, and they made no noise.

I am using an Audion Silver Night MKII 7W SET with 104db Klipsch La Scala's, and I cannot hear a sound, even with my ear next to the speaker. I had another pair of SET amps that were wonderful when the music was playing, but could hear the hum during the quiet passages.

Another fantastic amp is the Audiomat Arpege. Very engaging for all types of music.

All the best,
Howard

Sounds like you have ground loop issue. Also, a 300B SET can't really drive the 87db proac. This sounds like equipment mismatch issue.

Check out www.decware.com. Their Zen triodes are DEAD quiet, and oh so engaging!

I am definitely going to check out the ground loop issue immediately.

But, as regards the speaker issue, the ProAc 2.5s have an impendance curve of about 6.5ohms to 11ohms and an extemely benign phase angle which, even at 87db, makes them a very easy load. I've tried a well regarded speaker line that is marketed to SET users (92db model) and it was more difficult to drive properly than the 2.5s. Also, my room is small (11 x 13.5 x 8ft ceiling) and I sit at a medium distance so this also makes things better. I also tried a stand mounted two way rated at 91db which did not come to life like the ProAc. Finally, my amp is extremely well designed with huge Tamura trannies that are desgined for better drive characteristics than most SETs.

I have been poking around trying to find something easier to drive and as musical as the 2.5s for the last three years but have so far been unsuccessful. But I am looking for a 2nd amp with more power and will use for "power music" listening.