Power line conditioners..

[Notorious]

I posted that on other forums as well, but there was no answer..
There is so much tam-tam about power line conditioners, power cables etc. that I decided to try to build one of my own.. Now only schema's.. I'm not able to find anything on internet, so maybe you guy's know something that might help me..

I have to "feed" two Audio Research D-240 Power amps and SP-11 tube pre amp
so conditioner (or maybe two separate) would have to deliver about 4000 VA or more on 220/240~ v
Does anybody knows/have expirience building someting like that?
I've also heard that UPS units are good power conditioners, but they are made for computers so I have no idea if you can use them for Audio purpouses..

[Holger Barske]

My first suggestion would be: NEVER use any kind of line conditioner on power amps. The dynamic losses are bigger than the benefits in sonic precision.

[Magura]

Since you dont state where youre from its hard to help you on this one.

If youre from europe, youre gonna find it hard to get that kind of power out of a regular mains outlet.

Magura

[Duo]

I find that the best way to condition power easily is to use large isolation transformers. They will dissipate line transients, small spikes, and noise as heat in the core. This helps to reduce the amount of noise and fluctuation in on the secondary of the transformer.

This is not a perfect solution, however, it is easy to implement, simple to use, and quite effective for its simplicity. The only problem with such transformers, is the cost, they're not cheap.

I happened to obtain a 5KVA transformer for free, but I imagine that they are very expensive.

[SimontY]

Hi,

HBarske said:

My first suggestion would be: NEVER use any kind of line conditioner on power amps. The dynamic losses are bigger than the benefits in sonic precision.

I run my [integrated] amp off a 2KVA isolation transformer, which I picked up from Ebay for under 20 UK pounds. I also saw several 3KVA units going for a not unreasonable price. I'm guessing that would be enough.

Back to the point of sonics...: I need to reconnect my amp straight to the mains to really get a precise feel of the changes. But, from what I remember, I did lose a certain crunch from dynamics - this is probably mostly missed from rock music - the bass and drums. However, I did gain masses of warmth and softness, which in my system at the time was needed, and I've not felt the urge to disconnect it. I believe I also got a lower noise floor with better low-level detail and subtlety. I'm quite sure the soundstage expanded too. I'd say its a trade-off.

Based on my experience, my advice would be to try one, if you can get one cheaply, because to spend big money, then regret it, would foolish.

Another thing to try is to take a motor-run capacitor, or lighting capacitor (I have 10uf) and put it across live and neutral, and put some 'Y' class caps across live and earth, as well as neutral and earth. And put varistors across them all too. I made a filter like this, and it seems to add warmth and realism to the sound. But like before its so long since I plugged it in...

[johnferrier]

The 2kVA versions of the following isolation transformers are about 368$US (discounted with quantity FWIW):
http://www.belfuse.com/Data/DBObject/page_07.pdf They do generate heat; the ones I'm familiar with run about 70 degrees C (though rated for ~150 d. C).

PowerVar makes good power conditioners. http://www.powervar.com/navwelcome.htm No schematic on their site, although they have interesting white papers. Their ABC1200 uses 22uF motor start capacitors across the Y connection and a large multi-tap torroid transformer (~26 lbs). I prefer using it with a Yamaha mini-system.


JF

[Notorious]

I'm sorry Magura.. I live in Amsterdam Netherlands, and frankly I'm really satisfied with sound I have. I have friends in record industry coming over to my place to listen their master tapes. (Dat's and CD's) and there were even few records mastered at my place. But as I already said ther's so much talk about, that I got curious..

Anyway, I have beast of isolation transformer at home, but his nullast is about 3½ - 4 A and I totally agree with guys here that low and stageing get richer somehow. I feel little "Scrudgie" to live that thing on 24/7. I also have professional EMI/RFI filters used in army radio broadcast and I guess that helps too.
For power amps would be the best to "feed" them directly from mains without circuit brakers between,( tap directly from power cable..) but we all know how dangerous that is.. ( I know somebody in France that did that to power his Krell's up..)
Thanx for your feedback tho...
If anybody is interested, Here are few links to power conditioners.. Hope you guy's enjoy reading it..

[mrfeedback]

Originally posted by SimontY
....Back to the point of sonics...: I need to reconnect my amp straight to the mains to really get a precise feel of the changes. But, from what I remember, I did lose a certain crunch from dynamics - this is probably mostly missed from rock music - the bass and drums. However, I did gain masses of warmth and softness, which in my system at the time was needed, and I've not felt the urge to disconnect it. I believe I also got a lower noise floor with better low-level detail and subtlety. I'm quite sure the soundstage expanded too. I'd say its a trade-off.
In my experience running the system or at least parts of the system from an isolation transformer pays very nice sonic dividends.
First reaction may be that "a certain crunch from dynamics" is lost or lessened, but on closer listen these dynamics will be found to be FALSE dynamics.
These are products of distortions that also add harshness and masking to mids and highs.
Some recordings can 'glare' on certain notes and sounds, adding 'dynamics' but these are false dynamics.
A good recording played on a good system may initially sound dynamically flat, but further listening reveals more detail and less noise masking, and actually bigger real, more musically correct and satisfying dynamics and contrasts.
Studio master tapes sound clean and at controlled level, and do not have these transient dynamic peaking characters.

Based on my experience, my advice would be to try one, if you can get one cheaply, because to spend big money, then regret it, would foolish.
Yes, if you hunt at garage sales, flea markets etc you can find them cheaply.

Another thing to try is to take a motor-run capacitor, or lighting capacitor (I have 10uf) and put it across live and neutral, and put some 'Y' class caps across live and earth, as well as neutral and earth. And put varistors across them all too. I made a filter like this, and it seems to add warmth and realism to the sound. But like before its so long since I plugged it in...
I have found that varistors can add a 'layer' of fine dirt - long time since I tried them but that was my impression at the time.

Eric.

[SimontY]

Ahh, Mr Eric, you continue to educate me

I myself wondered if that leading edge impact type effect I initially missed was a false addition. One thing I have noticed with my system developing musically, is that it doesn't sound very punchy, in that it never really thumps the sound at me, like even maybe a £3-4000 'shop' system seems to. This is conterversial (to the measurement brigade perhaps?) and off-topic, but I believe this false [dynamic punchiness] character comes from using heavy metal and glass supports and stock, often soft, equipment feet. Perhaps the cabling too, and total lack of mains conditioning!

I've grown to dislike this false hi-fi shop sound, because it never quite fools me into thinking its real music. People have sometimes looked at my huge sub, and said "where's the bass then?" - and others have certainly thought it. But if I play a bassy track, say Bjork - Hyperballad, you wouldn't want anymore bass, it would be unpleasant (so loud and around 40hzish), and things rattle! My point is, with some of the things many people do (and fail to do) to their systems everything ends up sounding the same (coloured)!! I think every system needs attention paid to the power, of there will never be deep, rich bass, clear treble, or naturally warm mids. Of course, that attention could be paid inside the equipment

I'd like to add that I thought an isolation transformer might be a cure to my harshness and glare, Eric reminded me of this. It wasn't, it had only a modest effect in this department.
superfluous-- (I'm going to say this in every thread I post in now: it was Kimber cable that cured my harshness!! First 30% or so was cured by replacing main cable to amp, then an even bigger chunk was removed by internally wiring with Kimber. I love it so much, my white glaring sheen over all music has been turned off, forever!)

[Upupa Epops]

I can't imagine listening WITHOUT isolation transformer ! With this is sound much more clean and , as say mrfeeback , is without false signal , which somebody think , that is right sound. Everything is better - bass , trebles and mainly space in recording. If you have good apparatus , you must have this transformer - who says that not , don't know whatabout is good sound. Certainly this transformer must to have larger power , than is summary power of all apparatus ( 1,5 - 2 ).