Speaker noise - hissing

More info is needed.

What make and model for the amp? How old is it? Has it been serviced lately? How many hours are on the tubes?

Does the hiss occur when only the amp is on and no sources are connected?

Same with the speakers. If the speakers are particularly efficient you may notice hiss that a less efficient set of speakers would not reveal.

In short, the more information provided, the better the answer.

I've found that Sovteks and a lot of common Russian-made tubes can be quite noisy, especially the Sovtek 12AX7LPS. It most definitely is always the preamp tubes or the smaller tube types such as 12AX7/12AU7/12AT7, 5751, etc.. Never had noise problems with Output tubes.

Welcome to the musical world of tubes. In exchange for SS nasties, there is tube hiss...our imperfect world. The EH and Tungsol tubes are known to be very quiet. Get phono grade tubes if you want really quiet. I find the tubes at RAM/Rodger Modjesky, Tube Depot, and Tubestore have good quality. There are others, but I have purchased from these. jallen

Are you referring to a 50 watt power amp or integrated? You didn't mention whether you have a tubed preamp which would be the first source I would investigate.

Newbie hit it pretty much right off.

I've had noise on SS systems, running them single ended. I've even had some noise on Ss going XLR. the former interface being the more noiseier of the two.

In combo rig, Tube + SS amp, single ended only, there was a bit more noise than all single ended Ss gear would produce.

None of the aforementioned systems did however produce enough hiss or fuzz to be noticeable at less than enormous listening levels in between the tracks.

I'd have to get up and get close to the speakers to notice it... and turn up the volume while I was very close to the speakers. XLR is/was the quietest. All SS came in second. hs + SS was third... and the noisest was all tubes runing SE.

Again, I still can't hear even the loudest (all tubes) from my listening chair. I gotta get within a couple feet of the speakers with the volume up to hear the hiss.

Two things fixed or made it better... the phono line tubes, and power conditioning. A third item helped but in a much lesser degree... tube rings... oddly enough. They helped imaging too.

As was said, it only takes one to make things irritating. give Andy at Vintage Tubes a call.