[tomek]

Hi, I recently got a smaller ONEAC conditioner to use with my headphone rig, but I found that it emitted an annoying hum.  It wasn't incredibly loud, but it was certainly noticeable and irritating.

A friend of mine just got a bigger ONEAC conditioner and was really happy with what it did for his system, but complained it was even louder than mine.  I thought mine was too loud to begin with.

I'd like to pick up a ONEAC conditioner myself, a CB1115, but am weary since I can't even stand the computer on in the room when I'm doing my critical listening.

Anyone have experience with this?

[Bwanagreg]

I think it's a crap shoot. I have two of the 6 amp OneAC's (forget the model number) and they are stone silent. Of course, I also have them - and all of my gear - in another room away from the listening area just in case of this problem (my RAM CD player has more mechanical hum than anything else).

[Carlman]

Both of mine hum quite loudly.  I have an 1103 and 1107 IIRC.

I didn't hear much (if any) benefit to having these units (in stock form) in my system.

-C

[JoshK]

I have 4 OneAC units and none of mine hum.  Maybe I am lucky.  They definitely helped in many regards in my system.

[byteme]

I've got or had 4 oneac's and a powervar.  One of the Oneac's (CP1102) was brand new, no noise.  One (CP1102) was used and is quiet.  The third (CP1103) was used and hummed enough that I could hear it when it was quiet in the room.  Drove me nuts and now it's upstairs on computer duty.  The Powervar (ABC600) replaced the 1103 and was dead quiet until I plugged in the 4th item (it has 4 outlets) and I think I overloaded it, at that point it started humming.  To be fair, the 4th item was a 6 outlet strip so I pulled stuff off the strip until is stopped.  I'm glad that happened because it turns out it was my sub amp!!  Plugged into the digital side of the power supply.  My other Oneac (CP1102 again) hummed no matter what, but not too loud.  It's upstairs too now on the computer.  It is somewhat of a crap shoot, if you can find them new, typically, from my experience they are quiet - as long as you don't overload them!!

As for not making much difference, originally they made a noticable differnce to me, however, when I replaced the outlets with cryo'd Hubbell 5362 outlets.  Whoa - damn, BIG difference!!

[Jon L]

I've got or had 4 oneac's and a powervar.  One of the Oneac's (CP1102) was brand new, no noise.  One (CP1102) was used and is quiet.  The third (CP1103) was used and hummed enough that I could hear it when it was quiet in the room.  Drove me nuts and now it's upstairs on computer duty.  The Powervar (ABC600) replaced the 1103 and was dead quiet until I plugged in the 4th item (it has 4 outlets) and I think I overloaded it, at that point it started humming.  To be fair, the 4th item was a 6 outlet strip so I ...

Byteme, is that Hubbell IG5362 or plain 5362 you have?  I just had some IG5362 sent to be Cryo'd.  I'll be comparing them to ACME cryo outlets later.

As far as this noise problem.  You guys have to first figure out what type of OneAC you have.  They have mainly 3 types:  1) Isolation transformer(with some small caps for RFI filtering and surge protector), 2) ferro-resonant conditioner (has isol transformer also, but also has a HUGE motor-run cap inside looking like a big metal can), 3)UPS(should have some sort of battery backup).

#1 have very slight hum only audible when your ear is within inches of the thing.  Only if you overload the unit's rating, it'll start to hum loudly.  This stuff is best used with digital gear where it can do wonders.

#2 have the WORST noise problem.  They all have higher noise than #1, and most of them have a pretty loud noise audible from listening seat.  I've tried about 5 of these things and only one so far is quiet enough.  Audio use can be hit or miss, BUT if you stick your digital gear into #1 and plug #1 into #2, plug other gear into #2, things can sound quite good.

#3 should have the least noise as there is no isol tranformer or large caps.  The cheap ones sound like crap for audio.  However, expensive ones that output "true sine wave," are well worth the money (usually $800-1200 range) especially after a little mod.  BTW, this is what I use now...

[TheChairGuy]

Just in case anyone wants to try it...

I bought a CyberPower 1500AVR (UPS and Voltage Regulator)from Best Buy recently to use on my PC, monitor, printer, etc.

Of course, I had to try it out on my audio gear first.  Didn't sound bad at all after 48 hour run-in...almost the equal in benefit of my PS Audio 300 on front end gear.

It's a hefty bugger (but compact) at about 30lbs. and has a 1500v/amp capacity.  Connect your gear only to the UPS outlets (3 or them) and you have some effective voltage regulation for cheap. $179.99  

There is a closeout unit (very similar) in Best Buy for $149.99 called 1250AVR.  For front end, low draw components, it shouldn't make a hill o' beans.

It is a captive cord (14ga), so there may be additional benefit in chopping male end off and replacing with brass plated  one (should smooth out the sound a bit)

[byteme]

Jon L - I'm pretty sure they were IG's.  They were the ones that Virtually Dynamics was/is selling.  They are the ones reported to have the highest copper content.  I was planning on buying a bunch from a local electrical distributor for about $18/each and then sending them to get Cryo'd but I was able to pick up 6 of them for $150 shipped which was a better deal.  I believe that there is/was someone on a-gon selling these too.

[Jon L]

Jon L - I'm pretty sure they were IG's.  They were the ones that Virtually Dynamics was/is selling.  They are the ones reported to have the highest copper content.  I was planning on buying a bunch from a local electrical distributor for about $18/each and then sending them to get Cryo'd but I was able to pick up 6 of them for $150 shipped which was a better deal.  I believe that there is/was someone on a-gon selling these too.

You'll cry if you found out how much I bough the Hubbells for  

Let's just say it was less than $5 each.  I'm getting them double-cryo'd (double the cost).  Hope they are worth the hype.