Balanced or Not


I own a preamp which has both balanced and single ended jacks. I assumed that since I was using the balanced jacks I was getting the benefit of a balanced circuit. I have just now realized that just having balanced plug-ins doesn't mean your preamp (or any other component) is "balanced." Just wondering what sonic compromises are being made with equipment which has balanced inputs and outputs but that change the signal to single ended as it passes through it. If you are using the balanced outputs, what good is that if the signal going into this jack is single ended? Why would manufacturers do this? What is the advantage to not following the balanced circuit through completely?
frepec
Tube/SS, Vinyl/Digital, Balanced/SE, just relax, have fun and enjoy the music.
By jove, I think he's got it!!!
Thanks for the topic as I happen to be wondering if Bal or Unbal cables should be used for the female XLR to RCA outputs on my Fostex D5. The cable runs into my Denon DRA- 395.

Any suggestions are appreciated. r
Swampwalker,
Agree!
I`ve heard exceptional sound from both fully balanced and single end RCA systems. Can`t say one bettered the other.
Regards,
My preamp manufacturer mentioned to me that "RCA" is much more "musical" than XLR, even though he provided XLRs on the preamp.
For me it was an issue of "gain" in my system. XLR provided me with the necessary gain (twice the volts over the + and i terminals) and I am pretty happy with it. This is from a very recent upgrade from RCA to XLR between the preamp and amp.
Roscoe50, the best way of interfacing a balanced output to an unbalanced input is most likely with a Jensen transformer, as explained in section 3 of this paper. Examples of those transformers are shown near the bottom of this page. They cost around $200. If you want to pursue that approach, give them a call to obtain a recommendation of a specific model.

A less expensive alternative would be an ART DTI, specs shown here, although I can't vouch for its sonic quality.

Another alternative would be to have an adapter cable made up by a cable vendor, that connects XLR pin 2 to the RCA center conductor, and XLR pin 1 to the RCA ground sleeve. In theory a Jensen transformer is a better approach, but as a practical matter an adapter cable MIGHT provide results that are just as good.

The least preferable approach, IMO, although it still might provide satisfactory results, would be to use an adapter plus a separate cable, as you seem to be considering. If you want to try that I think it would probably be best to use an XLR-female to RCA-female adapter at the output of the Fostex DAT recorder, with an RCA cable connected from there to the Denon receiver.

The adapter cable approach and the adapter + cable approach will not provide any of the potential benefits of a balanced interface, regardless of the type of cable that is used, although as I say that might not make any difference in your particular setup.

Be aware, also, that most XLR to RCA adapters short XLR pin 3 (which is usually the inverted signal in the balanced signal pair) to ground (XLR pin 1). I suspect that won't cause any problems with your pro-oriented DAT recorder, but if you pursue that approach you might want to consider purchasing an adapter made by Cardas, which as I understand it do not short those pins together, at least on XLR-female to RCA-female adapters. Pin 3 SHOULD be shorted to pin 1, btw, when adapting an RCA output to an XLR input.

Regards,
-- Al