AC Power: Conditioners versus Synthesizers

HDTV Forum · Post by **HDTV Forum** » Sun May 23, 2004 6:53 pm

The PS Audio PS300 costs over $1,200. Would I see or hear enough of a difference with this product to justify that kind of cost? Sorry, I don't buy it (nor will I; I can make much better use of that kind of money).

John

HDTV Forum · Post by **HDTV Forum** » Sun May 23, 2004 6:53 pm

I'm an EMC engineer. I work with this stuff as a living. Most claims on this are pure hype. If you see interference, lines, intermittent hash, dropouts, etc. in your picture then MAYBE one of these will work. That's only if it's a conducted noise problem. It won't do anything if it's from radiated interference. If you have a noisy appliance like a vacuum cleaner or whatever, either put up with the temporary noise, try plugging into a different outlet, or buy a new appliance - probably cheaper than these rip-off conditioners. Same with light dimmers - just trash the old noisy thing and go buy a decent switch that doesn't generate interference. These conditioners won't do anything for a signal that impaired for some other reason. Put your money into more or better toys instead. These things fall into the same category as the rip-off cables with a $.50 ferrite core, and sold as a 'video enhancer' or something. These fall into the same category as the water pipe or gasoline line magnets and their ridiculous claims. I use ferrites when I have to for EMC reasons (country laws EMC/EMI limits). Sometimes they work great, a lot of times they don't do squat, but don't get ripped off and pay 50 bucks for one. If your equipment has FCC/CE/VCCI/C-tick/etc. marks it already has enough internal conducted filtering on the AC power. These are my thoughts based on my knowledge and experience. If anyone still wants to blow their money on these then go ahead.

emc guy

HDTV Forum · Post by **HDTV Forum** » Sun May 23, 2004 6:54 pm

EMC Guy, you are right on the money. Power conditioners do nothing except give some surge protection. That's all. A big rip off of those with deep pockets.

Jack

HDTV Forum · Post by **HDTV Forum** » Sun May 23, 2004 6:54 pm

Jack - agree on the surge 100%. Surge suppression is a different matter altogether, but high price doesn't guarantee anything here either. While I'm here for a few moments before getting back to work, I'll further annoy those folks who have spent their money yet claim they see an improvement. Well, for one, there's alway the psychological effect of seeing things that don't exist because it justifies the expense. The other is - they might have seen an improvement, but, it really had nothing to do with the conditioner! The reason is this: when you start messing around with your unshielded power cords and the typical rat's nest connecting your equipment, you are radically changing how cables pick up energy, radiate energy, and couple them together. Believe me, I can measure radiated noise in a special test chamber with a spectrum analyzer, and make a slight movement of a cable to see 10 dB, maybe 20 dB variation of noise levels at various frequencies. This makes a bigger difference than the filters several feet away from the equipment on the end of the line cord. The filter can actually make things worse! Equipment is designed and tested with the power cords terminated with 50 ohms to ground. These filters can make the equipment 'see' a high impedance at various frequencies if they have a choke on the load side. This can jack up the switching noise (from the power supply) radiating from the line cord. Now wouldn't that piss you off - you spent all this money and the problem got worse! In this example, the conditioner might have actually done something by making things worse.

emc guy

HDTV Forum · Post by **HDTV Forum** » Sun May 23, 2004 6:55 pm

"These fall into the same category as the water pipe or gasoline line magnets and their ridiculous claims"

You're right, dude. My water pipe work just fine without no magnets, man!

Cheech

HDTV Forum · Post by **HDTV Forum** » Sun May 23, 2004 6:55 pm

Nearly all the comments are correct when related to line conditioners and there is much vodoo involved. The PS Audio is NOT a line conditioner although there is some vodoo involved with some features which I do not recommend you use if your intent is accuracy. It is a 120V AC generator or more accurately an AC synthesizer with its own power supply and signal generator that puts out pure clean power for your equipment. It is not a joke, snake oil or a way to seperate you from your money. You are buying a 300/600/1200 watt amplifier and they can be expensive not to mention it is a niche market. If you are a videophile/audiophile then owning one of these should be in your future. It is a work horse you will own for many years and it will bring out the best and most accurate results from your equipment investments.

Richard F. Fisher

HDTV Forum · Post by **HDTV Forum** » Sun May 23, 2004 6:55 pm

Richard - it sounds like snake oil to me. Please explain, why you need to provide 'pure sine wave' AC power into a device which basically just chops it up, runs it through some mag components, then filters it to DC? Did you know that the equipment itself, especially if it uses switch-mode power supplies (almost everything these days does), will distort its own power source no matter how pure it is? This is called power line or low-frequency harmonics. Equipment is designed to handle a pretty good level of line distortion, noise, cycle dropouts, and brownouts and it will work just fine. If you bought a piece of equipment that can't handle something less than a 'pure sine wave' then basically it's a piece of crap. They must have really used a cheap-ass power supply with poor filtering. Good internal power filtering (DC side) is a requirement these days. You've got digital logic and DSP circuits running near analog amps and maybe RF. This is the biggest challenge - keeping all this stuff separate inside the same box. The AC side is electrically so far away that it just doesn't matter. By the way, get yourself a real power conditioner. These are the ones I use - http://www.pacificpower.com/

emc guy

HDTV Forum · Post by **HDTV Forum** » Sun May 23, 2004 6:57 pm

Richard - it sounds like snake oil to me. Please explain, why you need to provide 'pure sine wave' AC power into a device which basically just chops it up, runs it through some mag components, then filters it to DC?

Because noise rejection is typically only 30-50db.

Did you know that the equipment itself, especially if it uses switch-mode power supplies (almost everything these days does), will distort its own power source no matter how pure it is? This is called power line or low-frequency harmonics. Equipment is designed to handle a pretty good level of line distortion, noise, cycle dropouts, and brownouts and it will work just fine.

Working and reproducing accurately are two different goals. It is obvious that you don't need this for your stuff to "work". Nor do you need an ISF calibration for your display to have a picture.

If you bought a piece of equipment that can't handle something less than a 'pure sine wave' then basically it's a piece of crap. They must have really used a cheap-ass power supply with poor filtering. Good internal power filtering (DC side) is a requirement these days. You've got digital logic and DSP circuits running near analog amps and maybe RF. This is the biggest challenge - keeping all this stuff separate inside the same box. The AC side is electrically so far away that it just doesn't matter.

I am so glad that the professional community disagrees with you on this point and it has been documented. The PS Audio comes with a 30 day trial. If you can see or hear a difference then it was worth it. If you can't then it may be overkill for the quality level of equipment you have.

Richard F. Fisher

HDTV Forum · Post by **HDTV Forum** » Sun May 23, 2004 6:59 pm

Because noise rejection is typically only 30-50db

Vague, you're throwing out numbers with no definitions. Noise rejection depends on where in the circuit you are looking, required SNR, gain/bandwidth, and all sorts of things. Noise coming through power supplies from the AC is insignificant compared the the noise generated by the circuits on the DC load side. An RF gain stage may need much more than 50 dB rejection of supply noise to meet min. SNR. Each sensitive circuit needs to be designed to have adequate filtering and sheilding depending on what else is on the same supply or circuit board. Maybe your power conditioner will help if you're sharing your video equipment with a MIG welder. Otherwise the noise coupled through is a nit compared to what's generated internally.

Working and reproducing accurately are two different goals.

To my definition they mean the same. The equipment works to specifications and to how it was designed.

I am so glad that the professional community disagrees with you ...

Sure, when the 'professional community' is the same bunch of people making big bucks off this unnecessary equipment.

emc guy

HDTV Forum · Post by **HDTV Forum** » Sun May 23, 2004 7:00 pm

Richard,

If you can't then it may be overkill for the quality level of equipment you have.

Only the equipment that's lacking? I'm suprised that you didn't mention it could also be the abilities and/or skills of the listener. After all, not all are true audiophiles.

You're mellowing.

a