bottom line on UPS for small remotes?

[squeegybug]

Originally Posted by cleantone

Than what is all the talk about the square wave AC about? I'm getting more confused the more I look into this.

I'd like to repeat:

So how about a UPS behind a True Sine Wave Inverter? Would that make my rig happy? I assume it would not only benifit from the TSWInverter but if the UPS needs to kick in, the TSWI would sine the square?

Well, you are still running off wall current this way. Any voltage fluctuations are still going to be there, and the digital equipment will grab every peak it can. Of course most power supplies are robust enough to deal with this and not have functional problems, especially computers. But it does make a difference in the audio in my experience.

The little office supply switching UPS doesn't do any power inversion or filtering until the wall power fails. Whether it adds noise just being in the current path, I couldn't say, but have been told they can. And I know they are documented to cause lots of distortion when they switch over to battery.

The noise I was referring to from my online Liebert is mechanical acoustic noise from the big cooling fans. The audio itself is remarkably cleaner and quieter.

Steve

[TonyDigital]

Originally Posted by squeegybug

I bought an online sinewave Liebert UPS here:

Mine is the GXT-2000, don't see any of those in stock at the moment. Be aware they are *very* loud and heavy (about 80-90 lb), so not sure how one like this would suit your remote setup. I just put it in a machine room, powering my entire studio and a separate PC/laser printer. On wall power failure it has run up to 30 minutes perfectly. Don't know how long it would take to exhaust the batteries, and of course that depends on the load.

There is no question in my mind that this is one of the best (if not the best) additions I have ever made to my studio. The audio is truly smoother and fuller sounding, I have made comparison recordings to confirm this. Same thing, perhaps even more, on playback. Digital systems really like continuous sinewave power.

And of course the obvious advantages of avoiding interruptions.

Steve

Liebert makes a good products but I've always been a true APC believer. On our servers we run Smart-UPS 2200's and they're rock solid reliable. New or refurbished UPS, APC has always been a champ. We've tried some Liebert units but some of the tech guys weren't impressed with the reporting and communcations aspect, other than that the protection was great.


Tony

[caleymw]

Here's a question:

Do online UPS units present a different ground resistance than a straight wire, or is the ground path really completely unaffected? I assume the latter...

It has occurred to me that if there is any change in the treatment of the ground path, then putting any less than the entire system on a UPS might expose one to ground differential hum. And more generally, the idea of powering some part of an audio system with a different flavor than the rest seems potentially problematic.

Is there a best practice here, or does it matter at all?

[Rick Sutton]

Originally Posted by caleymw

Here's a question:

Do online UPS units present a different ground resistance than a straight wire, or is the ground path really completely unaffected? I assume the latter...

It has occurred to me that if there is any change in the treatment of the ground path, then putting any less than the entire system on a UPS might expose one to ground differential hum. And more generally, the idea of powering some part of an audio system with a different flavor than the rest seems potentially problematic.

Is there a best practice here, or does it matter at all?

When I've used a UPS on remotes it was only the AC source for the recorders involved while other gear sourced AC straight from the wall plug. I had no issues with hum.