1 (edited by AudioSource 2018-10-16 15:36:29)

Topic: Balanced Headphones

Let's assume to connect Main 1/2 through XLR Outputs directly to a balanced headphone. Would there be any downsite in comparison to the "Balanced Headphone Mode" apart from the power? Will it be enough to handle headphones?
The upside is, I still could use the channels 3/4.

I believe the XLR connections should stay the same? +, - and grounding separately.

2 (edited by AudioSource 2018-10-18 06:05:42)

Re: Balanced Headphones

edited: 18.10.2018 - 07:05

I have been digging around a bit to come to understand the approach of RME's concept "Balanced Headphone Mode" on four channels. Pretty impressive. In the manual "ground/shield" on the TRS is not connected. That scheme is correct, isn't it? Therefore the ground sound't be connected but isolated instead?

There is a downsite with the XLR method, mentioned in my previous post. It's only powered by two amps, which lead not to the same results as the quad differential amping alias "Balanced Headphone mode" in terms of THD, THD+N and power. The explanations here are mostly reliable https://www.headphone.com/pages/balance … ones-guide

If i still wish to connect XLR plugs to my headphones, will the connections be the same? 1: shield/ground 2: hot/+ 3: cold/black/-
I am just not too sure about the ground. Please could somone help me out with the XLR connectors? Help is really much appreciated.

3 (edited by ramses 2018-10-18 06:13:08)

Re: Balanced Headphones

AudioSource wrote:

I have been digging around a bit to come to understand the approach of RME's concept "Balanced Headphone Mode" on four channels. Pretty impressive. In the manual "ground/shield" on the TRS is not connected. That scheme is correct, isn't it? Therefore the ground sound't be connected but isolated instead?

There is a downsite with the XLR method, mentioned in my previous post. It's only powered by two amps, which lead not to the same results as the dual differential amping alias "Balanced Headphone mode" in terms of THD, THD+N and power. The explanations here are mostly reliable https://www.headphone.com/pages/balance … ones-guide

If i still wish to connect XLR plugs to my headphones, will the connections be the same? 1: shield/ground 2: hot/+ 3: cold/black/-
I am just not too sure about the ground. Please could somone help me out with the XLR connectors? Help is really much appreciated.

Not sure whether I understand you correctly. You do not connect balanced phones to the rear to the XLR outputs.
You use the phones preamp on the front, Phones 1/2 and 3/4.

Handbook chapter 18 shows an adapter that you would require if you want/need to use a 4-ping XLR plug.
Chapter 14.1.3 shows how to activate Balanced Phones mode.

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub13

Re: Balanced Headphones

ramses wrote:
You do not connect balanced phones to the rear to the XLR outputs.
You use the phones preamp on the front, Phones 1/2 and 3/4.

Why is that?
I don't understand your statement without an argument.

5

Re: Balanced Headphones

The rear XLRs have a source impedance of 200 Ohm which disqualify them for direct phones connection.

Regards
Matthias Carstens
RME

6 (edited by ramses 2018-10-18 06:24:36)

Re: Balanced Headphones

AudioSource wrote:

ramses wrote:
You do not connect balanced phones to the rear to the XLR outputs.
You use the phones preamp on the front, Phones 1/2 and 3/4.

Why is that?
I don't understand your statement without an argument.

You referred to the handbook without telling a page number reference.
So it was not clear to me what you really intend to do.
I only had the impression from what you tell, that you might want to use the rear ports for balanced phone use,
which is not the correct way to do it.

I only want to tell you, that for balanced phones use
- you need to use Phones 3/4 and 1/2 (the front output for phones, nothing from the rear of the device)
- you have either phones with 2 TRS plugs or might need the adapter which is shown in chapter 18

Meanwhile MC told you why. But even if you do not know the reason, the handbook tells you how to do it
and handbook quality is excellent with RME, thanks to MC for taking the time.

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub13

Re: Balanced Headphones

I gotcha guys. Thank you for your statements. I was not aware of an output impedance of 200 Ohms on the XLR outs. 2x 1/4 TRS with isolated ground works extraordinary good though.

Thank you!

Re: Balanced Headphones

Ever since I use a balanced headphone something wasn't just right in the audio chain. In case of the cable scheme I used RME's layout from the manual V 2.2 on page 38: https://www.rme-audio.de/download/adi2profs_e.pdf

I've been running some tests by listening to music, to celebrate my newly soldered balanced cables. It turned out for two balanced headphones, that the phase is inverted on both channels, when "Bal Phones Mode" is on. Additionaly tests with sample based noise impulses had shown that this suggestion was right.
It is possible to reconstruct the inverted phase polarity with a positive single sample impulse, by putting a headphone's loudspeaker closely to a microphone and mute the other headphone speaker. The recorded signal will become phase inverted. As soon as the "phase invert" switch on the ADI-2 Pro FS device was turned on, the sample based signal was positive (+). This procedure prooves a phase inversion somewhere in the chain.

I tripple checked the soldering scheme from RME, and also the 4-Pin layout of my headphone manufacturer and I can say either is true:
The soldering scheme for the +/- 1/4 TRS is inverted or the device has a DSP based phase invertion.

4-Pin XLR layout https://assets.sennheiser.com/global-do … l_0218.pdf

9

Re: Balanced Headphones

This is easy to answer: there is no phase error with the ADI-2 Pro, neither in normal nor in balanced mode. The error is in your external cabling, if there is an error at all.

Regards
Matthias Carstens
RME

Re: Balanced Headphones

My TRS connection is following, like described in the manual:

Right channel:
Tip: red
Ring: white
Sleeve: stays unconnected

Left channel:
Tip: blue
Ring: white
Sleeve: stays unconnected


MC wrote:
The error is in your external cabling, if there is an error at all.

What you are saying is that the wiring colors of the cable are inverted?

Right channel:
red: -
white: +

Left channel:
blue: -
white: +


I've never seen such a cable before. In fact, it would rather surprise me. I don't want to make accusations, nor do I want to pin point any fault. Until now, there is no standard for balanced headphones for wiring, apart from the 4-pin XLR's. For gods sake I am thankfull for TRS sockets.
However, as you can see, this phase issure is rather strange, don't you think? If you wish, I will add pictures as proof and a detailed report of my phase experiment, which in my current aspect proofes an inversion somewhere in the chain after my DAW.

11

Re: Balanced Headphones

I have no clue what this is about. Neither RME nor Sennheiser talk about colors.

Regards
Matthias Carstens
RME

Re: Balanced Headphones

How did you determine there is a polarity (not "phase") issue? How did you make sure there is no error in external cabling or test devices?


Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

13 (edited by AudioSource 2018-10-23 17:34:09)

Re: Balanced Headphones

Thanks to everyone for your posts.

I couldn't reproduce the error with a directly connected TRS Out to XLR In as phase reversed signal. There wouldn't be a reason for an error anyway since TRS and XLRs are standardized.

I got in touch with the Sennheiser support and I've been waiting so far to get a reply. I will keep this thread updated as soon as I have an answer about the respective wire connections.

14 (edited by AudioSource 2018-10-25 10:50:02)

Re: Balanced Headphones

The statement from Sennheiser is as expected. The wires I soldered and RME's schema do match. It means that I didn't make a misstake by swichting polarities in the soldering process. But the phase inversion is still present. Here a shootout, recorded with my mic, in the described method above on the headphone outs 3/4:

normal mode, Beyerdynamic headphone → normal phase
balanced mode, Beyerdynamic headphone → normal phase
normal mode, stock TRS cable Sennheiser, Sennheiser headphone → normal phase
balanced mode, stock TRS cable Sennheiser, Sennheiser headphone → normal phase
normal mode, confirmed balanced 2xTRS cable, Sennheiser headphone → inverted phase
balanced mode, confirmed balanced 2xTRS cable, Sennheiser headphone → inverted phase

Maybe the stock pins on the cable ends are inverted. I am going to solder a second cable anyways to drive my other headphone in balanced mode. I will update this thread.

Any suggestions so far?

15 (edited by ramses 2018-10-25 12:07:00)

Re: Balanced Headphones

AudioSource wrote:

Here a shootout

No clickable URLs found in your posting.

AudioSource wrote:

Any suggestions so far?

Simplify, as I mentioned in this or other thread already, the difference won't be audible anyway.

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub13

16 (edited by AudioSource 2018-10-25 13:11:32)

Re: Balanced Headphones

ramses wrote:
No clickable URLs found in your posting.

I didn't post a URL. What kind of further explanation do you need to clarify the topic?

ramses wrote:
the difference won't be audible anyway.

Then why can I hear it? It would have been impossible to notice a phase inversion without noticing it and post a threat for this purpose, don't you think so? Imagine complex transients like snares, vocals, bassdrums. Everything which comes phase inverted from the recording studio will not sound as expected. We naturally tend to like a positive-negative signals more, than negative-positive signals. Please let's stay focussed on the thread.

17 (edited by ramses 2018-10-25 14:20:52)

Re: Balanced Headphones

I though you mean with shootout that you linked information to this thread. Simply a misunderstanding.


> Then why can I hear it?

You mean the "phase issue" that you report ? Because smth might be wrong with the cabling ?! I don't know.
But to that in particular I didn't refer...

I simply mean that the difference between balanced and unbalanced operation of phones at these short cable length
is near zero, inaudible. You could simplify the setup by connecting the phones the usual way unbalanced.

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub13

Re: Balanced Headphones

ramses wrote:
the difference between balanced and unbalanced operation of phones at these short cable length
is near zero, inaudible.

I got your point and agree with the trivialness, wound't I be such a audiophile maniac smile
For the sake of audio quality: it sounds better.

19 (edited by ramses 2018-10-25 17:42:42)

Re: Balanced Headphones

AudioSource wrote:

For the sake of audio quality: it sounds better.

Sorry no, from my understanding this can not be the case. I cross checked this with google and
personally think that this can be regarded as "common sense" in regards to this topic.

1. Balanced audio is less susceptible to noise, allowing the use of long cables without degrading noise performance.

2. Because the 3 cables (hot, cold, ground) are twisted, balanced cables additionally reduce interference from magnetic fields.

So, keeping the noise floor ~3dB more distant (by slightly higher SNR) this doesn't make the music itself any better !
Its only 3dB less likely that you can hear any noise.
In fact with the ADI-2 Pro you do not hear any noise, be it unbalanced or balanced.

And .. in the range of ~120 dB SNR the noise floor is already so extremely low, so that the around 3 dB higher
SNR gives you neither noticeably / impressive results and especially not a better sound.

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub13

20

Re: Balanced Headphones

AudioSource wrote:

Everything which comes phase inverted from the recording studio will not sound as expected. We naturally tend to like a positive-negative signals more, than negative-positive signals. Please let's stay focussed on the thread.

For this very purpose the ADIs have the Polarity option. Just use it. You will have to do so anyway as one never knows which polarity the source has. You can then set the sound to your taste by a simple click. No soldering iron needed.

Regards
Matthias Carstens
RME

Re: Balanced Headphones

Ramses wrote:

I cross checked this with google and
personally think that this can be regarded as "common sense" in regards to this topic.

To google a topic and make some assumptions doesn't proof anything. I don't want to offend you, but please be aware that some parts of your statements are not even true.

MC wrote:

For this very purpose the ADIs have the Polarity option. Just use it. You will have to do so anyway as one never knows which polarity the source has. You can then set the sound to your taste by a simple click. No soldering iron needed.

Thank you for your concern. I am aware of the phase inversion, it bothers me to put it on and off all the time as soon as I change my headphones.

To conclude the topic I soldered another cable from Sennheiser. The exact problem in terms of phase inversion would occur on both channels, haven't I soldered them "phase inversed" instead. This leads to my final statement: due to the lack of standardization on balanced headphones plugs, sockets, cables and so on, this problem related to mine could happen to anybode who wants to drive a headphone this way. Sennheiser nor RME could implement a fully accepted standardization. When something trivial as an expected standardization is not cristal clear, one will ultimately do a lot of trials end errors to find out the real problem.

Thanks to everyone for the helpful replies.

22

Re: Balanced Headphones

I can easily proof your assumption to be wrong. I generate a digital + signal, which equals a positive DC voltage. It will be a positive DC voltage at the pin 2 of the rear XLR outputs, and the tip of the rear TS outputs, at the tips of the front TRS outputs, and in balanced mode again at the tips of both TRS outputs. This is a 'standardization' and it is fulfilled.

There is nothing inverted with the ADI-2 Pro or DAC. The balanced cable adapter diagram printed in the manual will work 100% correctly.

Regards
Matthias Carstens
RME

23 (edited by ramses 2018-11-18 21:58:25)

Re: Balanced Headphones

AudioSource wrote:

Ramses wrote:

I cross checked this with google and
personally think that this can be regarded as "common sense" in regards to this topic.

To google a topic and make some assumptions doesn't proof anything. I don't want to offend you, but please be aware that some parts of your statements are not even true.

Did you do blind or even better double blind tests to proofe your statement ?

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub13

Re: Balanced Headphones

I am having the same problem. I bought a Dyson audio balanced RME Adi 2 pro cable. I have tried to headphones with balanced cables. 1: A Hifiman HE-560 and 2: a Sennheiser HD600.
When I listen to Jamming from Bob Marley and the Wailers Legend, I am hearing the ring bell sound on the right ear. When I don't connect balanced cable(s) and use the stock headphone (unbalanced) cable, then the bell sound is coming from the left ear (where it should come from).

AudioSource wrote:

Ever since I use a balanced headphone something wasn't just right in the audio chain. In case of the cable scheme I used RME's layout from the manual V 2.2 on page 38: https://www.rme-audio.de/download/adi2profs_e.pdf

I've been running some tests by listening to music, to celebrate my newly soldered balanced cables. It turned out for two balanced headphones, that the phase is inverted on both channels, when "Bal Phones Mode" is on. Additionaly tests with sample based noise impulses had shown that this suggestion was right.
It is possible to reconstruct the inverted phase polarity with a positive single sample impulse, by putting a headphone's loudspeaker closely to a microphone and mute the other headphone speaker. The recorded signal will become phase inverted. As soon as the "phase invert" switch on the ADI-2 Pro FS device was turned on, the sample based signal was positive (+). This procedure prooves a phase inversion somewhere in the chain.

Re: Balanced Headphones

I am not that good at English. I should have writen it. I should also have written that I really love the Rme. Anyway, I Found the solution. Now I am listening again in balanced mode. It seems I have to connect the balanced cable in a specific order: Grey in the 1/2 input and black in the 3/4 input