Axiom Home Page Forums General Discussion Stereo Question About Tubes and Tubed Gear

Alright, so my YS-Audio Symphonies Plus preamplifier arrived in the mail yesterday. It's a very nice unit, great soundstaging and synergy throughout, it's gotten rid of that high frequency annoyance I was talking about previously; but now I have a different problem.

I hear this constant hiss, even when a input source is not plugged in coming from the preamp. It's very subtle, something you would hear on a cheap stereo with the volume about half way up to maximum. But compared to the previous gear I was using, which was a mackie mixer which was dead silent it's rather annoying.

Is this one of the 'characteristics' of tube designs or is it the preamp I'm using? Someone suggested replacing the recitifier tube and that didn't do anything either.

Also, I should note that moving the volume or balance control has no impact on the noise.

Hi Intricate,

The background hiss is just one of the intrinsic traits of tube gear, which has inherently more thermal noise than well-designed solid-state equipment. As you noted, most good solid-state gear is dead-quiet, unless you have an extra gain stage like a moving-coil transistor phono preamp. There is so much gain in the latter that it makes thermal transistor noise audible.

Late1960s and early 1970s transistor stuff often had audible residual hiss, but designs have greatly improved over the decades since.

Regards,

Alan and BrenR;
Thanks for the quick replies.

Well, I've used several preamps in the past; a H/K citation twenty-four, a carver (I don't recall the model number) a rotel RC-970BX, and I sold all of them because it all sounded pretty much the same... just with a little bit more or less THD.

And that's why I was using my friend's mackie in the meantime; but with the music I hear from my system with this preamp, the pluck of a guitar string on Eric Clapton's cds, or the resonant voice of Allison Krauss, I'm simply amazed.

I actually opened the unit up, fiddled around with the tubes a little; they have these metal caps to dampen microphonics I guess, one of them wasn't seated properly and it seems to sound better now.

Intricate,

Glad you got it sounding good. As I read these posts, I remember reading a study on pyscho-acoustics that found that when there is slight residual background hiss present on music recordings, like the kind you described or with tape or vinyl, many listeners actually "hear" more high-frequency content or detail. It's a strange phenomenon.

Or maybe it's just older audiophiles who grew up hearing music with background hiss present--it was a given for years in all recordings and of course vinyl too--so that when they hear the identical music with no hiss in the background, they describe it as "lacking detail."

I once suggested this to one of my regular record reviewers in Canada who had an enormous collection of vinyl that he always described as having more detail than CDs, and he became quite angry. . .

Regards,

Actually Alan, I'm 19 years old and I think that vinyl sounds better than cds as well. I can't figure out why but it just seems to be more pleasing to the ears, and there seems to be more treble-like detail.

Which reminds me, I should post pictures of my setup. But that'll have to wait, I let my bestfriend borrom my camera and he's in Italy.

Alan, I have to tell you though, the M80ti's are good musical speakers. Kudos for designing and selling them.

Vinyl... always with the vinyl...

Why doesn't my favorite format... *pause* *CHA-CHUNK* *pause* get any love?

Bren R.

*Edited to save myself from emberassment*

hehe.

Edited because I'm a really nice guy.