PS Audio Noise Harvester

Electroid ( and others ): If you go back in the archives, you'll find that i make mention of this type of occurance more than a few times. This is why i've talked about using a VERY LARGE isolation transformer ( with tweaks ) to feed the entire system and individual isolation transformers ( with tweaks ) at component level.

The primary iso gets rid of most of the crapola coming in on the mains. The individual iso's catch what has "leaked into" the AC feed between the primary iso and the outlets. As most of us know, the wiring within the house can and does act as a long wire antenna for both EMI and RFI, so the individual iso's help to act as a secondary filter in this respect.

On top of that, the individual iso's also keep the "internally generated garbage" of one component from being pumped back into other components via their common AC feed. That's because each component is now electrically isolated via the isolation tranformer.

Iso's work going both ways. That is, they not only keep the garbage from getting into the component, but also help to minimize the amount of garbage generated within that component from finding its' way back into the AC lines to contaminate other gear. The end result of such an approach is that you have cleaner AC coming in for all of the gear with a drastic reduction of cross-contaminated AC at component level. Sean
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I'm an iso fan but didn't realize how much gear piece #1 was affecting all the others and so on until now with the recent harvester tests. I have big CJ power amps that would need fairly hefty ISO's. Getting one for my P-300 which feeds my sources and passive pre (control aspect) and then one for each power amp would be nice. I would need three total. What tweaks are you doing to them? It would cost a good bit, have you tried harvesters vs ISO's or with ISO's? Do you like the double philosphy in that if you draw X current get an ISO that is rated at 2X? Thanks in advance! Nice post. And yes most of my noise is coming from my gear, it is not already in my line!

ET

Well, from the comments about the guy that cut one open, it is probably a parallel line filter. The usual reason for combining 3 or 4 caps in parallel is to reduce ESR (equivalent series resistance) which also changes the resonant point of the circuit. The capacitive value adds when they are paralleled (the opposite of risistors). If you really think this helps, make your own with some capacitors. It will be a LOT cheaper that way. As a starting point make the combined capacitance around 1 microfarad. If you like diy you might want to connect them across the back of the duplex outlet so you don't use up a socket.

Not having seen the inside of this thing it is also possible, since there was an inductor in it, that it is what's called a pi filter. It's called that because when you draw the schematic it looks a little like the symbol for pi. A little googling should provide you with more detail than I want to put into this thread. It's amazing how much is charged for things like this considering what simple circuits they are. There is nothing new about these filters other than marketing them to audiophiles for a lot of money.

They work because the electrical circuits in your house tend to act like antennas. The filters roll off the high frequencies (rfi). To optimize them you should figure out where the first and last outlets are on each of your house circuits (not just the ones you are using for your stereo) and place one at both locations on all your circuits.

I am trying out a few of these. The lights blink ONLY when I have a dimmer in use somewhere in the house. So I guess that is the only noise problem I have in my lines?

Drubin: That is an interesting observation that you shared with us here. Is your system on dedicated lines? Do you have more than one line, and if so, do you have your analogue separate from your digital, etc ??? Are you running any other type of power line conditioner and / or aftermarket power cords, etc ??? Where do you have the Harvester's in proximity to your system, etc ??? Sean
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