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Goth child
11-06-2009, 10:02 PM
Need some help guys!
Heres my system.
ATI At3000 2 channel power amp.
YS Audio Balanced a2SE tube pre.
Sony sacdx5400es cd player.
A1 dreadnaught.
Monster Hts1650 console.
Polk Audio SRS 1.2tl Rdo tweeters,no crossover upgrade.....yet.
Belkin high current power cables.
Wireworld Eclipse3 bi wired speaker cables.
Wireworld Eclipse3 balanced inter connects.

I have 2 small issues with my YS Audio Balanced A2 SE pre amp.
Firstly there is an audible hiss coming from the tweeters on my SRS1.2tls.
The hiss is in both channels and gets louder as I turn the volume up.
Secondly if I hold the volume control with my hand I can hear random radio stations faintly through the speakers!This is also both channels and gets louder as I turn the volume up.
Theres no faults with the pre switched off.The fault is on all inputs,EXCEPT the processor pass thru(Im assuming this bypasses the pres volume pot?)
Switching interconnects etc doesnt eliminate the problems.Im guessing its something to do with the volume pot???
Ricardo
11-06-2009, 11:23 PM
Have you tried a different set of tubes? I owned that pre and I can say it's the quietest tubed pre I've ever owned.
Goth child
11-09-2009, 12:16 AM
Have you tried a different set of tubes? I owned that pre and I can say it's the quietest tubed pre I've ever owned.

The pre is stock standard.I moved to a new town about 6 months ago and left everything packaged up while I was waiting for my Dreadnaught parts to arrive from the USA.It was about 3months before everything got set back up.The pre was much quieter and definately didnt pick up radio stations as background noise!
As a side note what did you replace your A2Se with?
Ricardo
11-09-2009, 07:08 AM
Ok. If it didn't have the problem before, maybe it's related to the power in your new home? Did you make any other change that could be a probable cause?

I replaced mine with a BAT VK-5i
Goth child
11-11-2009, 05:06 PM
I have tried it at another location and it is still noisey.Why does it get radio stations when I hold the volume pot?
Someone told me the volume pot might not be grounded properly.
TroyD
11-11-2009, 05:14 PM
sounds like a ground loop issue.

BDT
RuSsMaN
11-11-2009, 05:33 PM
It's a hiss not a hum big dumb.

Change the tubes out.
disneyjoe7
11-11-2009, 05:55 PM
Could it be just a loose tube, since it makes noise since he move it?
RuSsMaN
11-11-2009, 06:05 PM
All tubes exhibit microphonics, some more than others. He also just moved, box could have been bumped, dropped, bounced around, whatever.

I'd start with the tubes, I've picked up the local am news radio station on a preamp before.

Cheers,
Russ
187CAM
11-12-2009, 08:17 AM
Tubes
markmarc
11-12-2009, 02:52 PM
Start with the simplest solution first:

Put on your tube gloves and re-seat all your tubes.
Goth child
11-19-2009, 03:23 AM
Start with the simplest solution first:

Put on your tube gloves and re-seat all your tubes.

Ok.So I have lifted the lid and made sure the tubes are all tightly in place.I dont really know what Im doing ,so Im assuming thats what you mean by re seat?
187CAM
11-19-2009, 09:09 AM
Look at them all you want. Make sure they are all glowing. Make sure they have clean pins. Do whatever you want to THOSE tubes. Then try a new set. 12AT7's are easily found everywhere. Get some good ones like the British Military / Mullard's I have in my closet. I'm out of the Russian ones. LOL