Forum newcomer grok gave me an idea this afternoon. With the announcement of the Model 990, we've had a lot of discussion about some of its numerous features - including the balanced outputs. In fact, the debate evolved to a very technical level, and there is a ton of good info both for and against the concept of balanced connections. I suspect, however, that most potential 990 owners are going to be like me and hook it up to existing amps or buy amps like the 7100 or 770 to go with it, making the whole issue of balanced outputs moot, so it seems that we might try splitting things out. With that in mind, I'm starting this thread with the idea of letting folks compare their first-hand experience with balanced and unbalanced connections. What about it, folks? It's been a regular topic of discussion here, even before the 990 sprang up over the weekend. A central thread on the topic could be a chance to really kick some things around. (Just try to limit the kicking to ideas, not other gunslingers. )

Gonk, thanks for starting a new thread. Here is a good link to get the ball rolling.

http://www.audioholics.com/techtips/audioprinciples/interconnects/Balancedvsunbalanced.php

This is a very interesting topic that generates a wide variety of opinions from audiophiles. My personal experience with balanced signals has generally been favorable, particularly in regard to hum and noise rejection. The sonic differences are often quite subtle, and equipment must be designed appropriately to provide the full benefit. Many units offering "balanced " outputs simply use an additional op amp to create an inverting output, and this can actually degrade the sound. True balanced differential operation for 8 (7.1) discrete channels would require 16 separate paths for amplification, volume control, and (hopefully) D-to-A conversion. Another possibility would be the use of output transformers to galvanically isolate the signal, but that would also be an expensive solution requiring 8 discrete transformers. It would be distinctly unusual to find either of these approaches utilized in an inexpensive preamp/processor, but maybe the Outlaws have pulled it off. The Outlaw M200 amplifier is an example of true balanced differential operation and is among the least expensive quality amplifiers on the market. It is a shame that an XLR input wasn't provided to take full advantage of the design. As for the 990, perhaps someone in the know can provide the answer?

I’ve worked in many professional and enthusiast situations with both audio and video signals. As to transferring a signal from point A to point B:

The properties of the cables are more important than the cost and much more important than hype. I think it sad when people spend $25 or more per foot to move a signal a few feet in their house when the professionals that recorded the signals in the first place used great-quality cables at $2.50 per foot or less to move a signal over even larger distances.

In a system where various types of signals pass among several pieces of equipment, there are various potential sources of signal interference. Changing from unbalanced short runs to balanced short runs in just one portion of the signal path will not eliminate problems of a more fundamental nature. If you have only one problem area and that problem is due to long unbalanced interconnect runs, then balanced runs will help. Otherwise, the benefits of balanced lines are offset by the inclusion of additional electronics in the signal path to deal with a balanced I/O situation, and you’ll still have to deal with the other problems, such a ground loops, if you have them.

If my power amp(s) were on the order of 10 feet from my pre/pro, I’d use good unbalanced cables. If that distance were on the order of 100 feet, I’d use balanced runs.

No matter which option you choose, use quality cables but don’t pay for hype.

IMHO, Outlaw included balanced connections on the 990 and 790 more because of what some consumers have been led to believe and are likely to buy at that price point rather than the actual audio engineering needs of the majority of users. If you are one of the rare users that would benefit from balanced lines, then by all means run balanced lines.

For me, the balanced out will be an advantage. I use a tri-amped system and the electronic xover (which would is driven by the pre/pro) has balanced inputs. At the moment, I use a cable and short the - in of the channel. I would have preferred an unbalanced input for the xover, but I liked the unit otherwise, so I built the cables. I'll probably get a 990 and use the balanced outputs. My 2 cents...

So, for most of us, would using a balanced connection (if it were possible) make sense between the pre/pro and a sub woofer, given its typically a longer run than between pre/pro and amp? Is it possible and advisable to mix balanced and unbalance connections in a system this way?

When using a balanced connection, are the lost beneficial distortion aspects of any consequence given the restricted material found in the "dot one" channel?

I'm with Stabie. I also use pro active xovers and the balanced to unbalanced thing is a pain. It would be nice to have both to make it as flexible as possible.

Balanced is also nice since my gear is in another room and operated by RF remote, I can still place my amps very close to the speakers without worrying about spurious noise picked up from long interconnect runs.

Originally posted by Kevin C. Brown in the 990 forum:

SH: I thought balanced outputs (i.e., balanced interconnects) remove *all* noise on both sides of the circuit? Why would odd order be any different from even order? The "order" is just the relationship of the added components to the original signal. But out of phase is out of phase, and they should be removed just as well. ??

Just reposting it here for him.

Owl's- Thanks. I'll have to keep an eye on this thread too. I'm still making my way through that Audioholics post...

No problem. Frankly, I'm curious to the answer myself.