Balanced vs Unbalanced?


I am vaguely aware of the scientific merits of "Balanced wiring". I am only interested in the "Audio" merits.
CJ, a company that makes some of the best equipment on the planet, has no "Balanced" equipment that I know of. This puts some doubt on the audio merits of this circuitry. What is your opinion.
orpheus10
Alright, there is a fair amount of misinformation in this thread, and I thought since we essentially introduced balanced line operation to high end audio, I thought I should correct the misinformation herein and explain some of the whys.

Balanced operation exists for the sole reason of reducing/eliminating artifact in the interconnect cable. It will do so regardless of how long or short(!) the cable is. If it is set up right, it will always outperform single ended cables.

Balanced operation does not require twice as many components!! That is a very common myth. This is true even if the the preamp or amp is fully balanced. Now some balanced cirsuits will require twice as many components, and you will find that they also do not perform as well. The best balanced circuitry will also be differential. Differential circuits do not double components.

You can also run balanced operation without balanced components and realize all the benefits of the cables. This done via the use of transformers, as any transformer can convert from balanced to single-ended or vice versa, simply due to how its hooked up. I don't like transformers myself, but in cases where its either long interconnects or long speaker cables, the transformers and long interconnects will win out easily.

When I said that balanced operation is devised to eliminate cable artifact, I meant it- the cost of the cable becomes unimportant. However, to accomplish this, the balanced system has to be **low Impedance** (600 ohms is the standard, IOW what is driving the cable should be able to drive 600 ohms without distortion or loss of low frequencies). It is this last bit that has 90% of high end audio products falling flat on their collective faces, and is the reason why there is controversy about balanced at all. IOW if you don't embrace the standard, your balanced setup will be no better than single-ended and possibly worse.

Now if the components involved are internally balanced, you will realize two benefits: lower noise per stage of gain, and distortion cancellation with each stage of gain. So balanced preamps and amps can take advantage of that by using less gain stages as a result. This means that they will be more transparent, as reducing distortion reveals detail. I can expound more on that if you like.

Phono cartridges are balanced sources so LP can be run from needle to speaker fully balanced. The same is true of microphones and tape heads. CDs may or may not be balanced, but there is still advantage to using balanced operation with them due to the advantages of the interconnect itself. This is **not** to say that if your CDP is single ended that you can just stick a balanced cable on it and it will get better, it means that if you use it with a balanced preamp, the preamp will handle the signal fine and it will be delivered in better condition to the power amp.

I am certain I have forgotten a number of points but I expect they will come out in the responses to this post. The bottom line though is that balanced operation is a pathway to greater resolution and lower noise than is possible with single ended, but only if the standard is embraced.
I did forget something- a request. There are those of you here that disagree with my prior post and will have talking points. Please keep them if you can to one talking point at a time, so that we can be clear that they get responded to in a coherent fashion. Thanks!
Ralph, thanks for the excellent comments and explanations. FWIW, I am in complete agreement.

I would just add the thought that in principle it is certainly possible to use active devices, as alternatives to the transformers you mentioned, to fully achieve the benefits of balanced interfaces with designs that are not balanced internally. However, as you indicated most examples of that approach are not in compliance with the 600 ohm standard and/or are poorly implemented.

Best regards,
-- Al
I would like to point out that it's not all lollipops and roses. One unmentioned difficulty is that for everything to work as designed you have to have a circuit capable of producing 2 signals that are exactly the same except for their polarity. I agree that using a differential circuit makes it easier but there are still a lot of things that can cause an imbalance. If there were not the CMRRs achieved would be much higher than they are.

The other problem I see with Atmasphere amps is the OTL output. Ralph has done an admirable job of overcoming the stability problems experienced by earlier designs but I don't think you can overcome the inherent problems caused by paralleling a bunch of tubes and using them in a push-pull circuit. I have no explanation but cathode follower amps have never sounded as good to me as common cathode.

I have 3 directly coupled triodes and an output transformer between my source and my speakers which I believe leads to much better sound than you can achieve with a more complex circuit. Of course, if anybody wants to send me an OTL amp to try I would be happy to entertain them.

While I do agree with Ralph's explanation of the technical side of things I disagree that this leads to circuits that sound better than an SET, but of course this is a debate that cannot be won on either side.

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Herman,
IMHO, SETs are distortion generators. They can make a Yamaha violin sounds
like a Stradivarius. Like guitar amps, they should be considered more like a
musical instrument than audio reproducing equipment. Can SETs sound
good? Sure, I like them too. I used to built them when I was much younger.
But they are not Hi-Fi amps.

I know many people will disagree. Since we are talking about Hi-Fi here, Hi-
Fi or High Fidelity means faithfully reproduce. If an amp can make a Yamaha
violin sounds like a Stradivarius, it is not Hi-Fi, no matter how good it may
sound to some people.