• Registered: 2021-12-24
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Topic: Can XLR outputs drive headphones?

Hi, I'm planning to build a resistor box to put it between headphone and ADI-2DAC, in order to simulate higher output impedance. (about 120 Ohm) I know that balanced drive does not bring any practical advantage, and that ADI-2's high power 6.3 output offers higher voltage than any of line outputs. Though I prefer to do it with rear outputs because of aesthetic reasons. :-)
If I drive headphones with line output, will it damage the ADI-2 because of relatively low load impedance of headphones?

  • ning
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Re: Can XLR outputs drive headphones?

It won’t damage the device.

  • Registered: 2021-12-24
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Re: Can XLR outputs drive headphones?

Thanks, of course without any voltage drop with minimum 120ohm load impedance either?

4 Reply by ning (edited by ning 2022-01-03 00:54:32)

  • ning
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Re: Can XLR outputs drive headphones?

Of course there will be significant voltage drop. The xlr output has 200ohm output impedance. You will get very poor results when connecting any headphones (even 600ohm ones). It’a just the device won’t be destroyed by using those headphones as the 100ohms output resistance each side will provide stability(data sheet recommends >50 ohm output resistor for capacitive load and adi-2 has enough)/short protection to the op amp and the op amp itself has internal protection as will.

Opa1602 are designed to drive 2kohm loads. Your are not using it in the correct way though. You will end up with lots of heat and distortion…

If you just want to use a 120ohm resistor why not build it inside headphone cable?

5 Reply by KaiS (edited by KaiS 2022-01-03 01:27:19)

  • KaiS
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Re: Can XLR outputs drive headphones?

The XLR outs have an output impedance of 200 Ohms balanced (pin 2-3) or 100 Ohms single ended (Pin 2-1).

The resulting voltage drop into 120 Ohms headphones is:
-8.5 dB or factor x 0.375 balanced
-5.3 or factor x 0.55 single ended.

The OPA 1602’s maximum DC current of 55 mA limits the final output voltage into the 120 Ohms ‘phones to ca:
4.7 V / +15 dBu / 180 mW, same for balanced and single ended.

For most ‘phones this is way loud enough.
Most dynamic ‘phones will get a significant bass boost due to their driver resonance.
Nothing will break, nothing will excessively heat up and the sound quality will be OK if not driven too high.

Which headphones model you want to connect?


If for aesthetics, you could use an angled plug into the headphones out, alternatively.

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  • Registered: 2021-12-24
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Re: Can XLR outputs drive headphones?

My headphones are Beyer T1 1st gen with have 600ohm impedance.

So, there will be significant voltage drop and distortion, especially in comparison to its intended use.
But with 600 ohm headphones, I think I can just plug them into the rear XLR.
15dBu seems more than enough voltage.

Many thanks for the valuable information.
I didn't know about OPA1602 and its capabilities.

  • From: Norway
  • Registered: 2021-06-21
  • Posts: 398

Re: Can XLR outputs drive headphones?

What is the aesthetics point of this exercise. Maybe its do-able, but not ideal?

ADI-2 DAC, ADI-2 PRO, DigifaceUSB, UCXII, ARC, HEGEL.h80, KEF.ls50, HD650, ie400pro _,.\''/.,_

8 Reply by KaiS (edited by KaiS 2022-01-03 08:50:16)

  • KaiS
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Re: Can XLR outputs drive headphones?

IdleTalk wrote:

My headphones are Beyer T1 1st gen with have 600ohm impedance.

So, there will be significant voltage drop and distortion, especially in comparison to its intended use.
But with 600 ohm headphones, I think I can just plug them into the rear XLR.
15dBu seems more than enough voltage.

Many thanks for the valuable information.
I didn't know about OPA1602 and its capabilities.

Beyerdynamic T1, 600 Ohm is a different story.
Much lighter load than the 120 Ohm you originally asked for.

Voltage drop is only:
-2.5 dB / factor 0.75 balanced
-1.3 dB / factor 0.86 single ended.

Bass boost (at driver resonance) is just about 1/2 of above figures at max.
OPA 1602’s maximum current is no limitation into 600 Ohm.

Max. voltage is just ADI-2’s spec’ed values minus above voltage drop, more than enough to drive these ‘phones.
Max. drive voltage / max. power is:
13 V / 280 mW balanced.
8.3 V /  115 mW single ended.

No “resistor box” needed, just a correctly soldered cable for direct plug in.
There is no significant increase of distortion or other adverse effect.

Look at figure 12, red curve in OPA 1602’s datasheet to see what can be expected.
Still on par or better than what the DAC chip can do.
https://www.ti.com/lit/ds/symlink/opa16 … 52FOPA1604

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  • From: Hongkong
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Re: Can XLR outputs drive headphones?

WOW, if no resistor box needed, he can extend the XLR cable at the back of the DAC to his sitting position, make a wall outlet or something similar for the headphone ....

Pacifist, dumb, not stupid
Listen music out from a box which sounds
Reading words on paper/ screen
  • Registered: 2021-12-24
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Re: Can XLR outputs drive headphones?

Happy_amateur wrote:

What is the aesthetics point of this exercise. Maybe its do-able, but not ideal?

Indeed trivial thing, not even worth to mention.
The point was:  if there should be another small box near the ADI-2, I'd rather connect their back panels in order to avoid cluttering the front view. However it's a good thing that I don't need to make any "box".

  • Registered: 2021-12-24
  • Posts: 42

Re: Can XLR outputs drive headphones?

KaiS wrote:
IdleTalk wrote:

My headphones are Beyer T1 1st gen with have 600ohm impedance.

So, there will be significant voltage drop and distortion, especially in comparison to its intended use.
But with 600 ohm headphones, I think I can just plug them into the rear XLR.
15dBu seems more than enough voltage.

Many thanks for the valuable information.
I didn't know about OPA1602 and its capabilities.

Beyerdynamic T1, 600 Ohm is a different story.
Much lighter load than the 120 Ohm you originally asked for.

Voltage drop is only:
-2.5 dB / factor 0.75 balanced
-1.3 dB / factor 0.86 single ended.

Bass boost (at driver resonance) is just about 1/2 of above figures at max.
OPA 1602’s maximum current is no limitation into 600 Ohm.

Max. voltage is just ADI-2’s spec’ed values minus above voltage drop, more than enough to drive these ‘phones.
Max. drive voltage / max. power is:
13 V / 280 mW balanced.
8.3 V /  115 mW single ended.

No “resistor box” needed, just a correctly soldered cable for direct plug in.
There is no significant increase of distortion or other adverse effect.

Look at figure 12, red curve in OPA 1602’s datasheet to see what can be expected.
Still on par or better than what the DAC chip can do.
https://www.ti.com/lit/ds/symlink/opa16 … 52FOPA1604

Relieved to hear that. Thank you!

  • Registered: 2021-12-24
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Re: Can XLR outputs drive headphones?

Johannes AU wrote:

WOW, if no resistor box needed, he can extend the XLR cable at the back of the DAC to his sitting position, make a wall outlet or something similar for the headphone ....

Nice idea!

13 Reply by Johannes AU (edited by Johannes AU 2022-01-10 05:29:29)

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Re: Can XLR outputs drive headphones?

IdleTalk wrote:
Johannes AU wrote:

WOW, if no resistor box needed, he can extend the XLR cable at the back of the DAC to his sitting position, make a wall outlet or something similar for the headphone ....

Nice idea!


Thank you smile

Actually I have kind of idea before (which was asked by my friend who owns a yacht and want multiple output sockets at the boat, like power sockets, that he can plug the headphone wherever he likes), doubted if the XLR output of the Dac can drive balanced headphone or not, but impedance varies from phones to phones, and need some plug modification. Now I understand that is a solution there, even for active speakers with flexible location smile

Pacifist, dumb, not stupid
Listen music out from a box which sounds
Reading words on paper/ screen
  • KaiS
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Re: Can XLR outputs drive headphones?

Johannes AU wrote:
IdleTalk wrote:
Johannes AU wrote:

WOW, if no resistor box needed, he can extend the XLR cable at the back of the DAC to his sitting position, make a wall outlet or something similar for the headphone ....

Nice idea!


Thank you smile

Actually I have kind of idea before (which was asked by my friend who owns a yacht and want multiple output sockets at the boat, like power sockets, that he can plug the headphone wherever he likes), doubted if the XLR output of the Dac can drive balanced headphone or not, but impedance varies from phones to phones, and need some plug modification. Now I understand that is a solution there, even for active speakers with flexible location smile

Of course the headphones outputs can be extended and/or distributed too, and are much more universal in the use for headphones of all impedances and sensitivities.

KaiS's Website

15 Reply by Johannes AU (edited by Johannes AU 2022-01-10 07:54:00)

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Re: Can XLR outputs drive headphones?

KaiS wrote:
Johannes AU wrote:
IdleTalk wrote:

Nice idea!


Thank you smile

Actually I have kind of idea before (which was asked by my friend who owns a yacht and want multiple output sockets at the boat, like power sockets, that he can plug the headphone wherever he likes), doubted if the XLR output of the Dac can drive balanced headphone or not, but impedance varies from phones to phones, and need some plug modification. Now I understand that is a solution there, even for active speakers with flexible location smile

Of course the headphones outputs can be extended and/or distributed too, and are much more universal in the use for headphones of all impedances and sensitivities.


I told him already few months ago, but they prefer XLR fetish, kind of obsession..... They even ask the DAP manufacturer to use the ground contact of the pentaconn connector for their IEM ... they want to connect the ground to Entreq ....

Pacifist, dumb, not stupid
Listen music out from a box which sounds
Reading words on paper/ screen

16 Reply by KaiS (edited by KaiS 2022-01-10 08:35:29)

  • KaiS
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Re: Can XLR outputs drive headphones?

Johannes AU wrote:
KaiS wrote:
Johannes AU wrote:

Thank you smile

Actually I have kind of idea before (which was asked by my friend who owns a yacht and want multiple output sockets at the boat, like power sockets, that he can plug the headphone wherever he likes), doubted if the XLR output of the Dac can drive balanced headphone or not, but impedance varies from phones to phones, and need some plug modification. Now I understand that is a solution there, even for active speakers with flexible location smile

Of course the headphones outputs can be extended and/or distributed too, and are much more universal in the use for headphones of all impedances and sensitivities.


I told him already few months ago, but they prefer XLR fetish, kind of obsession..... They even ask the DAP manufacturer to use the ground contact of the pentaconn connector for their IEM ... they want to connect the ground to Entreq ....

There’s no reasonable way to connect the ground to balanced headphones / IEMs.
There’s simply nothing to connect it to.


ADI-2s XLR outs are only suited for higher impedance destinations.
600 Ohm are OK, below 300 Ohm you move outside of the used OPA’s spec’s.


So many myth-driven stupidity out there, it’s annoying.
In the net everybody can be an “expert”, no education needed, just enough followers.
The audiofool industry likes it, standing there, rubbing their hands and collecting the money for snake oil of all kind.

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  • Registered: 2021-12-24
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Re: Can XLR outputs drive headphones?

KaiS wrote:

There’s no reasonable way to connect the ground to balanced headphones / IEMs.
There’s simply nothing to connect it to.

Beyerdynamic connects the ground to their Tesla magnets.
However there's a user MOD to disconnect the ground to "open up" the sound.
What a wonderful(?) world...