[Haoleb]

I have been researching different products that eliminate DC riding on the AC mains while trying to pinpoint the problem I am having with my Odyssey Tempest preamp and of course this has led me here. The main question I have is what are the possibilities that this product could fix my problem? Of course Its impossible to say without trying it but Im guessing someone (Dusty) will have a better idea than I do.

I get a loud hum in the phono section, and there is audible buzzing from the toroid. I have done every standard thing to try and  find the problem possible. The only thing that had any real effect was running the preamp off of a battery backup device. Even though the transformer buzzed even louder when I had it running off of that, im guessing due to what probably looks more like a square wave than anything, I havent got an Oscilloscope so I couldnt say for sure. there have been a few people with the same exact problem and it seems to be due to certain ac enviroments.

Do you think it would be worth me giving the XDC-2 a try? Everything I have read about these type of devices is that they wont rectify any type of noise through the speakers, but since I dont think this is a ground loop type issue maybe it would? I have been looking into some DIY ones too since a premade one from any company will be nearly as much as I paid for the entire preamp so I may end up going that route. Basically looking for input from people who have used these things though.

Thank you!

[denjo]

Haoleb
I had an annoying hum from my amplifier transformer but when I swopped power cables, the hum totally went away. This was my experience which I thought might be helpful to you. I had no idea that a PC could make so much difference. If you really think about it, the PC is the vehicle that carries the power and a poorly shielded PC could be carrying all that RFI/EMI, even though your conditioners may have done a good job cleaning the AC power.

Hope you manage to remedy the hum problem!

Best Regards
Dennis

[Haoleb]

I only wish it were that simple. So far I have tried grounding more things inside the preamp, Turning every circuit off in the entire house except for a dedicated one I was powering the preamp off of, Tried lifting ground, Tried adding internal sheilds, Tried every type of outlet in my Monster HTS3600, Also tried my PS audio prelude PC on it. Nothing made any real difference. Grounding the circuit board to the chassis made a small improvement but that was it.

Only when I eliminated my AC power completely by using the battery backup the hum went away completely. We even have our own transformer for our house that is between us and the power company.

All these things were tested using a battery powered headphone amp that is dead quiet by itself.  The tempest is really sensitive in the phono stage with this problem for some reason, The regular inputs are unaffected. The only thing that both myself and Klaus who builds these things know is that it has to do with the effects that certain ac enviroments have on the preamp. Some people have no problems whatsoever!

[CIAudio]

It's possible XDC-2 could fix the problem, but you'd have to try it to know.

If DC is causing the mechanical hum, maybe the cartridge is picking up the vibration and then amplifying the noise through the phono preamp?

[HumanMedia]

If the D200 torroids are physically humming (which mine do), does this affect the performance of the amps?

The physical hum is annoying, but if i put the amps in an enclosure where I cant hear them, then is the problem solved?

Or does DC offset affect the torroid or any other components performance, and therfore the quality of the audio?

I guess the vibration alone caused by the DC offset cant be good for caps and other components, is this correct?

Are there any negatives of using the XDC on the D200s? (can the filtration be a negative)

[CIAudio]

DC can cause the performance to be degraded due to saturating the core of the transformer, but mechanical hum is what you'll notice most.

XDC-2 won't degrade performance in any way.

[Guliver]

Is there possibility for XDC-2 - 220V +with EU Shuko?

[CIAudio]

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Is there possibility for XDC-2 - 220V +with EU Shuko?

The 240V version (XDC-2S) uses Schurter IEC as shown below. A common cable to use between XDC-2S and the component is Volex 17525. 

[DaveX]

The 240V version (XDC-2S) uses Schurter IEC as shown below. A common cable to use between XDC-2S and the component is Volex 17525.

Dusty, I may purchase 2 of the XDC-2S's for my D200's from the UK distributor, 2 because I have the amps well spaced apart and one unit would share my pre-amp. Can the XDC-2S be placed very close to the D200. Thanks.


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