Power conditioner plugged into computer battery

APC recently introduced a series of power conditioners specifically designed for audio/video applications.

Their "S" Type AV Power Conditioner with Battery is pretty much exactly what you are looking for: "Pure sine-wave battery backup, surge protection, isolated noise filtering, and voltage regulation all combine in a single unit to deliver pure, uninterrupted power for high performance AV, home security, and automation systems."

I have been running its little brother - same without the battery back - since November and am very pleased with it. The system sounds very, very good...

http://www.apc.com/products/category.cfm?id=15&segmentID=1

I am thinking about one of the better power conditioner plugged into an APC computer UPS with battery. The battery is only to keep power coming when there is an outage. It's the audiophile grade power conditioner that corrects for problems. What I don't know are: (1) can the conditioner correct for typical square wave generation from the battery; (2) I heard it switches to battery mode during outage, thus is it true that during normal operation the power conditioner would receive fully non-filtered electricity capable of handling things like transient current spike needed for the amplifier. Manufacturers of audiophile grade power conditioners would most likely expect you to plug their equipment directly into a wall outlet, and not through a possibly filtered system like the UPS. So the easiest way to find out would be asking if anybody plug their power conditioner into a computer battery back up and find no degradation in sound.

If your battery backup system can handle the power-up current draw then you probably can find an acceptable match for your gear. There are a few caveats, but generally once your amp has charged up the banks then it's pretty much your amp's responsibility to provide the required regulated current - that's what those things are designed for.

The suggestion re: APC stuff is something to follow up on, if for no other reason than they usually have decent info on their Web site or linked discussions that can help you figure out what might work and what to avoid.

What are a few "caveats" you would consider as exceptions to the rule after an amplifier already charged up its banks?

I currently use an old Power Pack II connecting to a 1100VA APC computer grade UPS. There is no way that I can concurrently turn all stereo gears on at the same time; therefore, the APC didn't trip. So then are you saying that there is no current limitation on the amp when music is playing? APC, in their S-type presentation, remarks that transient current need on some amps could be as high as 30A.

I most likely need to upgrade the Power Pack II. Has anybody compare APC S15 to the established audiophile power conditioners? Secondly, does anybody know if there is no power outage, then the computer grade APC UPS simply works in the bypass mode, sending unfiltered electricity into its outlets? It comes across that this square wave problem only play in when the UPS battery must be used. Thank you.

Please note that the APC unit provides a pure sinewave - as opposed to square wave power. Sinewave is what you need - computers don't care, and it is more expensive to produce sinewave power.

Secondly if you search the Forums you will see that almost all UPS, isolation transformers and the like limit current.

As Mr Hosehead suggests, it may be that once the UPS reaches full charge it will simply pass current straight through - there are only two ways to verify that, either measure it yourself or talk to the manufacturer. Since that would increase the cost and complexity of the unit with no benefits for its target market, my experience suggests that its unlikely.

The one way I know how to do it for sure is to use a 2,000-3,500w sinewave inverter tied to a large 12v battery bank. This type of unit which is designed for off-grid and marine applications, has a very fast switchover from the AC mains to the DC banks. It is also large, heavy and relatively expensive.

Finally I have compared the APC to both Equitech and BPT - the APC product is unique in that it is the only audio/video product that I am aware of that has a battery back-up. (This includes Running Springs, Chang, Gray etc)

Your engineering premise is fine - you just won't find what you are looking for at a low price point.