Is there much, if any, benefit to balanced headphones?

[Count Arthur]

There are quite a few headphone amps and even DAPs available with a balanced heaphone output.

I've never tried it and I've always been curious as to whethere there is much difference when compared to the single ended output on the same amp with the same headphones?

 

[solderdude]

the search function gave me this link

 

[daftcombo]

the search function returned this picture:

 

[Count Arthur]

So that's a "NO" then.

 

[westyjeff]

The only difference is that some headphone amplifiers have a higher power rating on the balanced connector.

 

[Count Arthur]

I don't think I need more power, my current amp gets plenty loud enough. It has a feature that automatically switches from low to high power mode as you increase the volume and even with 300 ohm Sennheiser HD650s, with the exception of a few albums that are noticeably much quieter than the others, it will get way too loud for comfort before switching into high power mode.

 

[majingotan]

There are quite a few headphone amps and even DAPs available with a balanced heaphone output.

I've never tried it and I've always been curious as to whethere there is much difference when compared to the single ended output on the same amp with the same headphones?

Depends on the DAP output impedance (which can be different on balanced and unbalanced) and IEM pairing (not headphone). With headphones, there is ZERO difference except for volume while with IEMs, if the OI on balanced is slightly higher than unbalanced, that said IEM might sound "more diffused" due to damping factor variation across frequency

 

[Veri]

Some amplifiers actually perform better balanced. but then this is basically a design flaw...
Something like the THX AAA performs identical on SE/Bal, except that balanced goes further in power, should that be desired.

 

[Hipper]

Here's another thread:

https://www.audiosciencereview.com/...us-unbalanced-headphone-amplifier-drive.2327/

 

[Tks]

Mitigation against ground loops and the hums they cause.

Usually more power output (I can think of only one unit off the top of my head where they purposefully quelled power output because they felt 4V being pushed to headphones is overkill to which I agree). I think balanced XLR interconnect connections inherently can transmit more power safely as opposed to RCA.

A more robust and sturdy interface connection (the XLR connectors' pins for example either make contact at the same or they don't, as opposed to 6.3mm, 4.4mm, 3.5mm, 2.5mm, AUX/TRS/Jacks whatever you want to call them, need to be fully inserted for a full connection). Also a more secure connection due to the interface design and size.

Longer cable lengths afforded by the noise rejection as well.

Aside from that, that's pretty much it.

 

[Fluffy]

There is a clear difference. Balanced connectors or more "high end", therefore the manufacturer can charge more money for a device that has it. The more they use the word "balanced" in the description – the higher the profit margins.

But seriously now, today there is no actual need for balanced headphone connectors. The time of extremely power hungry planar magnetics has passed, and any respectable SS amp with SE jack can power pretty much anything. Also, the whole "less crosstalk" myth is totally bogus.

 

[March Audio]

Mitigation against ground loops and the hums they cause.

Usually more power output (I can think of only one unit off the top of my head where they purposefully quelled power output because they felt 4V being pushed to headphones is overkill to which I agree). I think balanced XLR interconnect connections inherently can transmit more power safely as opposed to RCA.

A more robust and sturdy interface connection (the XLR connectors' pins for example either make contact at the same or they don't, as opposed to 6.3mm, 4.4mm, 3.5mm, 2.5mm, AUX/TRS/Jacks whatever you want to call them, need to be fully inserted for a full connection). Also a more secure connection due to the interface design and size.

Longer cable lengths afforded by the noise rejection as well.

Aside from that, that's pretty much it.

Balanced headphone outputs are a bit of a misnomer. It's not the same as a balanced component Interconnect. There is no noise benefit and a ground loop isn't possible.

Power differences? Well if you raise the output voltage of a common ground amp it will do the same.

The only difference is a small benefit to crosstalk with a 4 pin connector V a 3 pin connector. It's measurable, in my tests the difference between 115dB and 123 dB, but that's in no way audible.

 

[Tks]

Balanced headphone outputs are a bit of a misnomer. It's not the same as a balanced component Interconnect. There is no noise benefit and a ground loop isn't possible.

Power differences? Well if you raise the output voltage of a common ground amp it will do the same.

The only difference is a small benefit to crosstalk with a 4 pin connector V a 3 pin connector. It's measurable, in my tests the difference between 115dB and 123 dB, but that's in no way audible.

I agree. For whatever reason, my dumb self was just talking about balanced in a high level generality. I just read the title and saw he was specifically asking about balanced headphone out. Sorry about that, and to OP, that was just rambly what I said.

 

[3font]

Comparing at the same sound output levels (same voltage across the headphones):

• If the performance nonlinearity-limited, "balanced" output will allow the positive/negative portions of the output driver to run at half the voltage and potentially improve linearity.
• If the performance is noise-limited however, noise spectral density should be ~3dB higher and "balanced" will degrade THD+N, with the degradation amount depending on the measurement bandwidth.

The latter would probably be more likely with today's excellently linear amplifiers.

Also note:

• Output impedance is doubled in either cases, so load impedance fluctuation-related problems would worsen (not a problem if the output impedance was already very low).
• Some amps report quite different stereo crosstalk values for single-ended vs "balanced", e.g., -90dB vs -127dB for the Monoprice AAA 887

Is any of this audible? Likely not, but I do subjectively like the look and feel of the XLR connector

 

[Schackmannen]

https://benchmarkmedia.com/blogs/application_notes/audio-myth-balanced-headphone-outputs-are-better Excellent article on this topic.

 

[March Audio]

https://benchmarkmedia.com/blogs/application_notes/audio-myth-balanced-headphone-outputs-are-better Excellent article on this topic.

This is bang on correct.

 

[solderdude]

The only difference is a small benefit to crosstalk with a 4 pin connector V a 3 pin connector. It's measurable, in my tests the difference between 115dB and 123 dB, but that's in no way audible.

That is seen from the connector side with a certain load impedance. For headphones the essential difference lies between a 3-wire cable (common return wire) and a 4-wire cable with low impedance headphones.
A very good example is the AudioQuest Nighthawk that purposely made a cable with a high resistance return cable.

The difference in crosstalk between the 2 suplied cables (the thread is about cables) is an audible 10dB. The silver cable has -34dB crosstalk and the gold one -24dB. These are audible levels and explain differences between the 2 supplied cables when using music.

 

[solderdude]

4V being pushed to headphones is overkill to which I agree

That depends on which headphone it is and how loud one wants to play. There are several headphones that need more than 4V (sound level/output voltage is logarithmic so to get a few dB more the output voltage needs to be higher quickly)
Headphones with a sensitivity below 100dB/V may well benefit from more than 4V as a maximum output voltage when you want to turn up the volume shortly for critical or 'lifelike' listening levels.

For normal listening levels you are correct. 4V will be enough in those cases.

It's a bit like saying a 300W amp in a living room is not needed.

 

[March Audio]

That is seen from the connector side with a certain load impedance. For headphones the essential difference lies between a 3-wire cable (common return wire) and a 4-wire cable with low impedance headphones.
A very good example is the AudioQuest Nighthawk that purposely made a cable with a high resistance return cable.

The difference in crosstalk between the 2 suplied cables (the thread is about cables) is an audible 10dB. The silver cable has -34dB crosstalk and the gold one -24dB. These are audible levels and explain differences between the 2 supplied cables when using music.

The OP specifically referenced amps not cables, but anyhoo, yes the bigger problem is the cable. Any cable that uses 4 wires with separate and not common 0 volts (even if terminated into a 3 wire connector) will not have an audible issue. Any cable should have appropriately low R, Land C.

 

[solderdude]

Indeed the amps are not really the issue. Also the plug doesn't have to be.

I've never tried it and I've always been curious as to whethere there is much difference when compared to the single ended output on the same amp with the same headphones?

If there is an audible difference between the same amp and the same headphone does not depend on the amp, is what I intended to clarify.
It is the cable (3 or 4 wire), the common return wire resistance in relation to the headphone impedance (and in some cases maximum output voltage).

So with the same headphone and the same amplifier (SE or balanced) the answer is... anything between no audible difference and an audible difference in the stereo imaging depending on the headphone and above all the used cable.

By definition one could say the balanced cable/headphone (4 wire) is always the better choice but in most cases there is no audible benefit unless the SE output has a low maximum output voltage.