|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
71.126.128.15
LinkyThe above (click "free" on the right column) is the background noise to my phono preamp. I remove my computer's power cord part of the way in, which is the quiet part, then replace it (when the noise cuts back in). There's a bit of hum and radio interference regardless but unplugging the computer kills most of the noise.
I can't plug the computer in anywhere else; all of my stereo is plugged into the same power strip as it out of necessity. Would a power conditioner eliminate the power line noise or is it due to something else? I don't want to drop a few hundred without knowing that it might help.
And should I get one for my whole hi-fi or just one of those two-outlet dealies to plug my computer and a power strip (with the stereo) into? I have a two-watt 45 amplifier so it's hardly starving for power (two watts, even into medium-efficiency speakers, is plenty loud enough for me, by the way; your results may vary but it's amazing how little I needed the other 148W when I moved down from solid-state).
Follow Ups:
Well, the problem is that the switching power supply in your computer generates RF . . . and your phono stage is picking it up. This may be coming back through the powerline . . . in which case a good power conditioner or power strip with isolate outlets (especially ones for digital components). If you follow Bambi's suggestion and get a non-toroidal isolation transformer, that might work too. . . just be sure that the computer is plugged into the power on the primary side of the transformer. I specify non-toroidal because these units have a higher RF rejection than toroidal units.My concern is that the computer is radiating RF into the air, which your phonostage is picking up. If that's the case, no amount of power conditioner, isolation, etc. will do the job. Because of their high gain, phonostages are particularly susceptible to RFI. Relocating one or the other might help. Having them close to each other is definitely not good.
Is there any way you can just shut the computer off when you're playing records? That would be the best . . . and the cheapest solution.
"If you follow Bambi's suggestion and get a non-toroidal isolation transformer, that might work too. . . just be sure that the computer is plugged into the power on the primary side of the transformer. I specify non-toroidal because these units have a higher RF rejection than toroidal units."You can do two things here: you can add a faraday shield on the primary of the toroidal transformer, or use a RFI/EMI filter on the AC input to the toroidal transformer.
Then again; you can also put photographs of your self in the freezer, which is cheaper than buying Bybee purifiers.
d.b.
for those of us concerned about sound.
The photos in the freezer tweak works like gangbusters. For those concerned about sound.
I have not tried the photo in the freezer. Can you describe the technique? Any thoughts on why it works?(I do not demand understanding from a tweak to use it. I have been happily using the Bedini for over a decade. As a matter of fact, a demonstration of the Bedini impressed and mystified my biggest skeptic friend.)
Winthorpe: Please email me for technique....no need to upset the locals....:-)
Well, if you were overweight and put photos of yourself on the outside of the fridge, it might encourage you not to eat.The . . . um . . . "belt effect," right?
Hey; I'm in the middle of quitting smoking, so I'll deal with losing weight later. :)
d.b.
aerobic exercise -- running, swimming, cycling -- cures smoking.A few hours of hacking and wheezing all of that crap out of your lungs is a powerful disincentive to putting more crap in from a cigarette.
I know.
I know somewhere between 'jack' and 'shit' about this kind of stuff. Thanks for the simple explanation...Yeah, I do unplug my computer when I listen to records. It'd be nigh-unlistenable without it!
It probably doesn't help that the phono stage is about the cheapest tube one made (a Ming Da MC767-RD). I really have mixed feelings about buying cheap Chinese crap; on the one hand, it's buying Chinese and not American or British, and all sorts of things go with that... but then again, I'd never be able to afford my tube system without Ming Da and Antique Sound Lab (although in my defense, I didn't know that ASL was Chinese until I read the first line of the manual: "For avoiding vacuum tubes damaged, please don't make carton being upside down." ASL manuals are a hoot). And they're the only two Chinese things in my whole system; everything else is either homemade (by somebody else) or from a U.S. manufacturer. Still...
But yeah, if I had more money to spend, I probably wouldn't have this problem. But I'm not rich by any means... ah, money. Must be funny in a rich man's world.
Mark Tinordi,I had a hum problem with my office system as I had intercionnected a synthesiser keyboard, the computer- whoch I use for HD recording, and the audio system, but there were all these different grounds. One of the problenms with having a computer connected to the same power as the audio system is that the computer is usually also connected to the phone or TV cable for the Internet, and these lines have separate grounds. In my case it was all the different grounds causing the problem.
To solve this and provide the best surge protection, I bought an 11Amp Oneac hospital isolation transformer power conditioner on Ebay for $50- plus $40 shipping (it weighs more than 40 lbs) and plug everything into that except the power amp, which, on Audio Research advice, goes directly to the wall to the same outlet as the Oneac. This $90 solution solved all my hum problems and I'm convinced the system is more dynamic and coherent. -The Oneac new four years ago cost about $1,200.
By the way, I recommend buying a 10Amp conditioner or higher- a 6.5 Amp Powervar proved to restrict the sound slightly, whereas the 11A Oneac and a 10A Powervar are just fine. And buy with a minimum of 6 outlets so you can plug eveything in to the same place. The Powervars are reasonably priced also- the 10A was $75 with $25 shipping a few months ago.
Here ya go
Mark
If you dont have a place to plug in your stereo on a separate line,the balanced power unit can help but I dont think a line conditioner will help.Do you have a tube or ss preamp..In my tube preamps like the mac c22 and the audio research sp6 both of which are tube,they isolate very well from the computer and thats because of the power transformer isolating the circuitry from the AC line per say.You may be able to put a small active line filter on the preamp rather than buy a power unit which is expensive.
This post is made possible by the generous support of people like you and our sponsors: