There is crud in AC.

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woodsyi

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There is crud in AC.
« on: 23 Sep 2010, 02:33 pm »
I was reminded just how much when I was moving plugs around in search of what I thought was a ground loopy noise (induced by a battery powered phono stage of all things).  With all else being the same, my amps were putting in some serious background noise when directly connected to the AC outlets.  When I put them back on my AC regenerator, Purepower 2000, background noise calmed down.  With the number of tubes in the chain, my system is never going to be silent but feeding the tubes clean AC and steady voltage definitely keeps the noise down and stable.   :thumb:

Out of the many power "conditioners" I tried a few years back, this was the only one that did not choke my amps at full throttle.  I had my issues with it as I had to return several units for failure.  But they seem to have righted the ship with the 2000 model.  I was habitually blowing out the 1050 model and I really think I put too much load on it.  The company gave me a free upgrade to 2000 (after several free replacements of 1050) and provided the mod kit to reduce the fan noise, which I understand is now a standard option.  It's been good for over a year now.  I would now recommend it, especially for anyone using a lot of tubes. 
« Last Edit: 23 Sep 2010, 03:39 pm by woodsyi »

*Scotty*

Re: There is crud in AC.
« Reply #1 on: 23 Sep 2010, 03:31 pm »
I got the same bad news about the AC power when I put Occam's Felix power filter in my system.
The change for the better with the Felix in the system was dramatic to say the least. Unfortunately some attempt to clean up the AC power your system receives must be made in order to successfully pursue better sound quality.
Scotty

mort

Re: There is crud in AC.
« Reply #2 on: 23 Sep 2010, 03:42 pm »
With all of the cash that people put into their systems, I am a bit suprized that more folks are not producing their own power with high end pure sine wave inverters wired to a dedicated battery bank. The inverter/charger could charge the battery bank when the stereo is not in use and be disconected from the grid durring critical listening. This power source would be infinatly cleaner than any public power utilities.

srb

Re: There is crud in AC.
« Reply #3 on: 23 Sep 2010, 04:35 pm »
With all of the cash that people put into their systems, I am a bit suprized that more folks are not producing their own power with high end pure sine wave inverters wired to a dedicated battery bank. The inverter/charger could charge the battery bank when the stereo is not in use and be disconected from the grid durring critical listening. This power source would be infinatly cleaner than any public power utilities.

If you're going to use batteries for listening, why go to the expense of charging them with expensive "high end pure sine wave inverters"?  Dirty AC power feeding a standard charger should be able to charge the batteries just as well.
 
Steve

*Scotty*

Re: There is crud in AC.
« Reply #4 on: 23 Sep 2010, 05:03 pm »
Mort is talking about going off the grid,(ie using the batteries to power the pure sinewave inverter).
By generating his power from an inverter which could power an entire house with low harmonic distortion 60Hz AC he is free to use any equipment he wants and is not limited to equipment that must be battery powered.
This approach is on my short list when I move back into a single family dwelling unit.
Scotty

srb

Re: There is crud in AC.
« Reply #5 on: 23 Sep 2010, 05:18 pm »
Mort is talking about going off the grid,(ie using the batteries to power the pure sinewave inverter).
By generating his power from an inverter which could power an entire house with low harmonic distortion 60Hz AC he is free to use any equipment he wants and is not limited to equipment that must be battery powered.
This approach is on my short list when I move back into a single family dwelling unit.

I see.  So this system would be similar to whole house solar cell powered systems with AC inverters.  Would the intention be to power one or more stereo or home theatre systems with dedicated lines to the A/V rooms?
 
In other words, not interfaced with the main breaker panel like the whole house systems, but an independent system with it's own dedicated lines?
 
Do you have any links to these smaller scale systems that you may have looked at?
 
Steve

*Scotty*

Re: There is crud in AC.
« Reply #6 on: 23 Sep 2010, 05:58 pm »
I don't have any links stored about smaller scale systems. One of the reasons for going with a whole house capable inverter with guaranteed low harmonic distortion AC capability is to try to keep your AC impedance as low as possible to avoid compression on dynamic peaks. The transformer on the pole can supply an enormous amount of amperage and has a very low dynamic impedance and it would be advantageous to try get near the point of diminishing returns with your inverter size. A fifty amp inverter might do the job but the odds are that 200 amp unit will sound closer dynamically to a direct connection to the main line.
You could run a separate system with dedicated lines but I am inclined to try to go off grid for my whole house.

Scotty

turkey

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Re: There is crud in AC.
« Reply #7 on: 23 Sep 2010, 06:09 pm »
Other than a simple filter that's built into the power strips I use, I rely on the power supplies of my stereo equipment to remove the "crud" from AC.

So far it's worked well.

 :thumb:

chlorofille

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Re: There is crud in AC.
« Reply #8 on: 23 Sep 2010, 06:16 pm »
... I rely on the power supplies of my stereo equipment
So far it's worked well...

 :thumb:

Agreed.
Ever since I started using choke loaded (CLC) power supplies for my amps, all that AC garbage has disappeared. Hail the mighty chokes !!  :thumb:

woodsyi

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Re: There is crud in AC.
« Reply #9 on: 23 Sep 2010, 07:31 pm »
Felix definitely helped on source equipments.  I am sure designers put in filtering (including choke, pi, etc) in PS as best as they can, but I find them inadequate in most cases, especially in big power amps requiring large current/voltage.  I have not found many "conditioners" that will not limit a pair of 200W KT99/6550 tube monoblocks.

mort

Re: There is crud in AC.
« Reply #10 on: 23 Sep 2010, 09:15 pm »
Indeed what I am refering to is using a Outback 2500 watt pure sine wave inverter (aprox $1800.00) that drives a four plex outlet dedicated to audio only. This set up provides a constant out put of twenty amps with a limited time output of up to 60 amps clean a/c power. Hardly any gear short of a concert P.A. system even aproches these power consumption levels under normal use. The outbacks are extreamly fast and quite. listining while the system is charging would be possible as a pass through from the grid, with the inv/chrgr sipping power to meet the batteries charging demands however I beleive that the charging process would introduce noise so listening would best be acomplished durring invert only.

Quiet Earth

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Re: There is crud in AC.
« Reply #11 on: 23 Sep 2010, 09:32 pm »


I have a very small AC generator for my turntable motor and it gets quite warm. I only use it when I'm spinning a record. I can imagine that a full system regenerator would be a beast.

How much energy is required to generate your own 20 amp sine wave?
Is there a lot of heat involved? Can you leave it on 24/7? How long do batteries last? Do they go into the landfill?

Why not build a better power supply as suggested above? Just curious . . . . .

srb

Re: There is crud in AC.
« Reply #12 on: 23 Sep 2010, 09:47 pm »

How much energy is required to generate your own 20 amp sine wave?
Is there a lot of heat involved? Can you leave it on 24/7? How long do batteries last? Do they go into the landfill?

Here is the product sheet for them:
http://lib.store.yahoo.net/lib/wind-sun/fxvfxspecs.pdf
 
The efficiency is quoted at 90% - 93%, so they seem to be much more efficient than small consumer inverters I have seen.
 
Steve

AKA KURO

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Re: There is crud in AC.
« Reply #13 on: 25 Sep 2010, 08:51 pm »
Quote
So far it's worked well

Until, that is, you try a truly high-end solution, such as Torus or Richard Gray.  You really need some isolation on your front-end pieces, amps notwithstanding.  THEN you will hear something that really works well, unless you have perfectly clean and stable AC in your house. 

turkey

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Re: There is crud in AC.
« Reply #14 on: 27 Sep 2010, 03:26 pm »
Until, that is, you try a truly high-end solution, such as Torus or Richard Gray.  You really need some isolation on your front-end pieces, amps notwithstanding.  THEN you will hear something that really works well, unless you have perfectly clean and stable AC in your house.

Thanks for giving me my morning chuckle. :)




« Last Edit: 30 Sep 2010, 02:17 pm by turkey »

BaMorin

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Re: There is crud in AC.
« Reply #15 on: 16 Nov 2010, 04:22 pm »
Until, that is, you try a truly high-end solution, such as Torus or Richard Gray.  You really need some isolation on your front-end pieces, amps notwithstanding.  THEN you will hear something that really works well, unless you have perfectly clean and stable AC in your house.

I have a Gray's power station that I run most of my equipment through. The first problem I had with it, was hooking it up to the big ol' Sony wide screen.
The second problem I had was the stereo store didn't have another one. It took me about 8 months before I could pry it out of my wifes hands and move it to where it was intended. The stereo sounds better, the picture on the Sony is back to........ummm "store normal"

Vapor Audio

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Re: There is crud in AC.
« Reply #16 on: 16 Nov 2010, 04:54 pm »
Indeed what I am refering to is using a Outback 2500 watt pure sine wave inverter (aprox $1800.00) that drives a four plex outlet dedicated to audio only. This set up provides a constant out put of twenty amps with a limited time output of up to 60 amps clean a/c power. Hardly any gear short of a concert P.A. system even aproches these power consumption levels under normal use. The outbacks are extreamly fast and quite. listining while the system is charging would be possible as a pass through from the grid, with the inv/chrgr sipping power to meet the batteries charging demands however I beleive that the charging process would introduce noise so listening would best be acomplished durring invert only.

This is an interesting solution, and I'd like to learn more about it.  I'm in the process of building a dedicated room and powering it is obviously a big consideration during the build.  Unfortunately finding an electrician who has any idea what I mean when I say I want the cleanest AC possible is like looking for a Unicorn.  So I'm going to have to research my own solutions and tell them how to implement them. 

mort

Re: There is crud in AC.
« Reply #17 on: 17 Nov 2010, 01:57 am »
This is an interesting solution, and I'd like to learn more about it.  I'm in the process of building a dedicated room and powering it is obviously a big consideration during the build.  Unfortunately finding an electrician who has any idea what I mean when I say I want the cleanest AC possible is like looking for a Unicorn.  So I'm going to have to research my own solutions and tell them how to implement them.
the other cool thing about this set up is that if your power goes out your stereo wont, you can still listen!

HAL

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Re: There is crud in AC.
« Reply #18 on: 17 Nov 2010, 02:19 am »
The Xantrex Prosine 2.0, 2000 watt true sinewave inverter has lower garanteed THD than most of the competition when I was looking.  It also has a remote start function that makes it nice to remotely place the unit for use since it has a cooling fan.  I found a refurbished unit for about $750.  Works well for backup power. 

An interesting side is that the PS Audio Power Plant Premier has lower output distortion than the Prosine.  I measures 2% THD on the Xantrex and 0.5% THD on the PPP running from the wall.  Both work well. 

raindance

Re: There is crud in AC.
« Reply #19 on: 17 Nov 2010, 02:30 am »
I was reminded just how much when I was moving plugs around in search of what I thought was a ground loopy noise (induced by a battery powered phono stage of all things).  With all else being the same, my amps were putting in some serious background noise when directly connected to the AC outlets.  When I put them back on my AC regenerator, Purepower 2000, background noise calmed down.  With the number of tubes in the chain, my system is never going to be silent but feeding the tubes clean AC and steady voltage definitely keeps the noise down and stable.   :thumb:

Out of the many power "conditioners" I tried a few years back, this was the only one that did not choke my amps at full throttle.  I had my issues with it as I had to return several units for failure.  But they seem to have righted the ship with the 2000 model.  I was habitually blowing out the 1050 model and I really think I put too much load on it.  The company gave me a free upgrade to 2000 (after several free replacements of 1050) and provided the mod kit to reduce the fan noise, which I understand is now a standard option.  It's been good for over a year now.  I would now recommend it, especially for anyone using a lot of tubes.

OK, so battery powered products cannot cause ground loops. Phono stages are high sensitivity so they can pick up noise coupled into the cables through the air, or noise can be added through the phono ground lead because the battery powered unit is ungrounded.

The ground loop must have been elsewhere. The reason your amps quietened down is most likely because the power conditioner provided isolation and in so doing removed the ground loop.

There is no way at all that noise on AC mains can get into the filtered DC that powers the innards of your amplifier unless it is a poorly designed amplifier and then it would be high frequency hash that is easily filtered out in a well designed power supply.

I don't recommend running amps off any kind of AC regenerators as I find it kills dynamics. I advise filtering the power to noisy digital devices and plugging amps straight into the mains.

By the way, you'd get more improvement by increasing the guauge of wire between your breaker box and your outlet for your audio gear.

Also, make sure your grounds are not daisy chained (like most outlets are wired in houses in the USA). Each outlet you use for the same audio system should have a unique ground wire run back to the house ground buss bar. Daisy chained grounds will cause ground loops.

Lastly, make sure you do not have a cable box connected to your system in any way shape or form. It will add a ground loop for free. You can buy ground loop isolators for the RF feed, but that's another story.

Just my 2c, but hopefully it will save some folks a buck.