[elmoe]

Thank you, I appreciate you taking the time.

 

[ruthieandjohn]

Chord Electronics, for one, eschews the inclusion of balanced outputs, stating that single ended is better for its high end equipment.

Yet many other vendors highlight balanced as an advantage, with one, Sony, even introducing a new connector, the 4.4 mm jack, for robust, compact balanced connection.

I don’t hear a difference, and I have not seen any blind studies that indicate a difference, nor have I seen any signal differencing comparisons, in which samples from a single ended and a balanced version from the same source are time aligned, subtracted, and the residual signal either listened to or analyzed (power, etc.).

 

[ostewart]

isn't there also the argument that certain brands deliberately make their "balanced" output on portable players sound better than their single ended ones. This tricks the consumer into thinking that it's better because it's balanced, and not because the circuitry is slightly different (A&K and Sony have been accused of this I believe).

I'm a skeptic when it comes to balanced vs single ended, especially with headphone amps, in terms of sound quality increasing anyway. A well designed amp should sound the same out of the balanced and single ended connections, only the balanced tends to output more wattage usually. But again it depends massively on the brand.

 

[gregorio]

I don’t hear a difference, and I have not seen any blind studies that indicate a difference, nor have I seen any signal differencing comparisons, in which samples from a single ended and a balanced version from the same source are time aligned, subtracted, and the residual signal either listened to or analyzed (power, etc.).

There are a couple of reasons for that:

Firstly, there are several variables involved: The amount of interference present, cable length and it's construction/shielding and therefore the amount of that interference that will be "picked-up" and, the amount of subsequent amplification of the signal (which includes the "picked-up" interference). It's trivially easy to conduct a blind test where the difference is clearly audible, given sufficient amounts of these variables but it wouldn't tell us anything beyond the system the blind test was conducted on, because these factors all vary between systems and listening environments.

Secondly, although balanced audio is a relatively new thing in the audiophile world, it is in fact a very old thing and not just some old scientific thing/curiosity that languished in obscurity until recently but one which was massively researched, developed and implemented at the time. That "time" started in the 1880's with the emergence of the telephone industry and it's need to transfer analogue audio signals over long distances and cope with another emerging technology, the electrical power distribution network, where mains power lines were commonly run alongside telephone lines for many miles and introduced a great deal of interference. The financial incentive to improve signal integrity (and/or maintain it over longer distances) could hardly have been greater, the president of Western Union reportedly said that if he could buy the telephone patents for $25m (getting on for $1b in today's money) it would be a bargain and that was when the telephone was still little more than a prototype! Telephony rapidly became a critical application and a matter of national importance/security for all developed countries and the amount of investment in scientific research, development, testing and then implementation was unprecedented. By the 1930's, balanced audio signalling had been researched to death and the effects of interference/noise was already old news, well known and understood in great detail. The studies/tests "that indicate a difference" are therefore probably around 130 or so years old (which is why you haven't seen any) and pretty much all of the testing/studies from about 1900 onwards were regarding better implementations of balanced technology, for example twisted pairs, number of twists per foot, amplification, etc. Most of modern audio recording/reproduction has it's roots in the research already carried out by the telecommunications industry by the 1930's, including digital audio which was proposed by an AT&T research scientist in 1928.

isn't there also the argument that certain brands deliberately make their "balanced" output on portable players sound better than their single ended ones.

I haven't heard of this but I wouldn't be surprised, it's an old audiophile marketing trick that's been used numerous times to artificially manufacture an audible benefit/improvement and thereby justify a more expensive product.

G

 

[SilverEars]

With it, I can try switching between SE and balanced headphone cables. I think there might be a very slight difference in FR in which SE has slightly more mids and balanced having slightly recessed. But it's slight and maybe intentional with the amp.

My main point is that you shouldn't discredit an amp if it's "merely" SE: a well designed SE amp will perform better than a poorly designed "balanced" amp.

It's interesting you say that because I have noticed similar for balaced output of a particular full-sized headphone amp, mids did sound dipped in comparison to SE. It also sounds like L and R are much more separated. The mids sounding dipped I wasn't fond of, but the more separation of channels increase the perception of sound stage width. Could be that the mids recession could have contributed to the perception of increased sound stage width.

I haven't tried out too many DAP balanced outputs, but it doesn't seem like blalaned outputs on DAPs sound better, but in ways seems like they sound slightly worse. This is with iems.

isn't there also the argument that certain brands deliberately make their "balanced" output on portable players sound better than their single ended ones. This tricks the consumer into thinking that it's better because it's balanced, and not because the circuitry is slightly different (A&K and Sony have been accused of this I believe).

I'm a skeptic when it comes to balanced vs single ended, especially with headphone amps, in terms of sound quality increasing anyway. A well designed amp should sound the same out of the balanced and single ended connections, only the balanced tends to output more wattage usually. But again it depends massively on the brand.

Those two brands were the ones I'm referring to that I don't notice balanced sounding any better, but just louder and maybe slightly worse.

 

[Davesrose]

It's interesting you say that because I have noticed similar for balaced output of a particular full-sized headphone amp, mids did sound dipped in comparison to SE. It also sounds like L and R are much more separated. The mids sounding dipped I wasn't fond of, but the more separation of channels increase the perception of sound stage width. Could be that the mids recession could have contributed to the perception of increased sound stage width.

Yeah, I also think that if it's an intentional difference in an amp's balanced vs unbalanced, the slight recession is for sound stage. I like that the iCan is only half rack size but outputs up to 14W in 32ohm. Only main disadvantage is that the tubes for tube mode are internal and makes tube rolling difficult. But when I've tried SE solid state: sound quality sounds identical to the headphone stage in my source (Benchmark DAC), and tube mode sounds very similar to my other SE tube amp. I wonder how many people who've criticized this amp for not having enough "micro-detail" didn't try it with SE output.

 

[bigshot]

Gregorio, are there any good books on the history of Bell Labs and the other sound research groups in the 1920s? I have some books on early recording, but they focus primarily on the acoustic era and playback machines. I'd be interested in reading about the research that led to them.

 

[pstickne]

Chord Electronics, for one, eschews the inclusion of balanced outputs, stating that single ended is better for its high end equipment.

I wish more companies put their foot down on making technical instead of pure market-chasing choices (and use/spin those to sell to a more ‘educated’ consumer, of course).

Of course, pretty pictures with a few technical looking words sell a lot (of junk), as evident by most any Amazon audio equipment listing..

 

[bigshot]

The junk sounds just as good

 

[pstickne]

The junk sounds just as good

Depends on which is being talked about.. there are definitely good sounding and reasonably built low-cost products and extreme ‘price value ratios’. Then there is literal junk.. same “impressively technical” pictures.

My biggest gripe about Amazon et. al. is lack of single-product single-brand (ie. too much rebranding of the same OEM/source), and I digress again.

Anyway, same issue: products chase the marketing more than the objective technicalities, where such marketing is compounded as the followers chase ‘audiophile’ leaders.

 

[bigshot]

I guess I don't care about brands. I just want it to work. If it doesn't Amazon takes it right back and refunds my money. I like that.

 

[Dogmatrix]

I believe the main advantage of true balanced architecture ie 4 amplifiers is the positive drive of both sides of the transducer . A very different situation to common noise rejection in cable transmission which is largely irrelevant to headphones .

 

[old tech]

Gregorio, are there any good books on the history of Bell Labs and the other sound research groups in the 1920s? I have some books on early recording, but they focus primarily on the acoustic era and playback machines. I'd be interested in reading about the research that led to them.

Not Greg, but the wikipedia article has a good summary and the references at the bottom can be a good starting point.
https://en.wikipedia.org/wiki/Bell_Labs

 

[gregorio]

Gregorio, are there any good books on the history of Bell Labs and the other sound research groups in the 1920s?

Not that I know of, although if there isn't, there should be! My knowledge/assertions comes from the opposite direction. Over the years of learning/studying about individual aspects of pro audio, the trail almost invariably led back to the telephony industry and by far the most commonly, specifically to Bell/AT&T. This is because AT&T held the original telephone patents and figured that in order to stay ahead of the pack of (national and international) competitors it had to come up with new practical ideas/patents. Because of this and the huge resources at it's disposal, by the 1920's AT&T employed around 3,500 of the best research engineers and scientists. While this is not uncommon today amongst telecom and information technology giants, it was utterly unprecedented at the time, plus, there was a lot more to discover about audio back in the 1920's than there is today.

We tend to think in terms of a recent/modern revolution in technology but that's not entirely true, the technology revolution started with the practice (and results) of massive commercial investment in technology R&D, which AT&T pioneered more than half a century earlier. Having said this, much of the basic principles/properties/behaviour of signal transmission were not only already known before AT&T even existed but had actually already been implemented on an inter-continental scale. By the start of the 1870's the British had direct telegraph connections (using under-sea cables) from mainland Britain to multiple different continents (even as far as Australia, on the opposite side of the world) and by 1911 the "All Red Line" was complete, a telegraph network with multiple redundancies that circumnavigated the entire planet.

[1] I believe the main advantage of true balanced architecture ie 4 amplifiers is the positive drive of both sides of the transducer .
[2] A very different situation to common noise rejection in cable transmission which is largely irrelevant to headphones .

1. I'm not sure I understand what you're saying. Firstly, if you were to provide a "positive drive" to both sides of the transducer, the net result would be no movement/sound. Secondly, I'm not sure what you mean by 4 amplifiers, presumably you mean the two amplifiers converting two (stereo) unbalanced signals into the 4 signal balanced stereo, plus the two differential amplifiers in the receiver/s (say transducers). However, the two receiving differential amplifiers output just two signals (the two stereo channels), the same as a stereo SE architecture.

2. No, it's not a different situation, there is only one situation and that's common mode noise rejection. A differential amplifier takes two input signals and creates a single output signal that comprises ONLY the difference between the two input signals. The two input signals are the original (unbalanced) signal and the original (unbalanced) signal with it's polarity inverted. As these two signals are exactly opposite, the difference between them is exactly the same as the original signal, which is what the differential amp outputs. However, any noise/interference picked-up by the cable is picked-up more or less equally across both signal wires and therefore affects both signals more or less the same.. As this noise/interference is the same on both input signals and as the differential amp is only outputting the differences, that noise/interference is therefore ignored (rejected). That's it, that's all a balanced architecture does, there's no other "situation" or magic occurring.

G

 

[bigshot]

Found a book on Bell Labs! https://amzn.to/2Xzpjin