• exact
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Topic: Using RCA for speakers and XLR for tubes at the same time?

So currently I run my ADI-2 DAC with a speaker-amp connected to it via RCA. I use HD800 straight from the RME. But I was thinking of getting a tube-amp to try with my headphones. If I get an RCA-XLR-cable to connect the tube-amp to the RME's XLR-inputs, I'm all good? The tube-amp that I'm currently looking to get only has RCA-inputs, same goes for my speaker-amp.

I get that the audio will play on both RCA and XLR at the same time, but that's easily solved with just turning my speaker-amp off while using the tubes, yeah?

Just want to make sure I'm all good here.

  • KaiS
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Re: Using RCA for speakers and XLR for tubes at the same time?

exact wrote:

...If I get an RCA-XLR-cable to connect the tube-amp to the RME's XLR-inputs, I'm all good? The tube-amp that I'm currently looking to get only has RCA-inputs,
Just want to make sure I'm all good here.

Be sure to have the XLR cable wired according to the manual, page 37:

Quote:
The XLR line outputs do not operate servo balanced! When connecting unbalanced equipment, make sure pin 3 of the XLR output is not connected. A connection to ground might cause a decreased THD (higher distortion) and increased power consumption!

XLR Pin 3 should be left open.
This is a bit non-standard, usually XLR Pin 3 is connected to ground in XLR-RCA cables and adapters.
A snipping tool can “convert” those.

KaiS's Website

  • exact
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Re: Using RCA for speakers and XLR for tubes at the same time?

KaiS wrote:
exact wrote:

...If I get an RCA-XLR-cable to connect the tube-amp to the RME's XLR-inputs, I'm all good? The tube-amp that I'm currently looking to get only has RCA-inputs,
Just want to make sure I'm all good here.

Be sure to have the XLR cable wired according to the manual, page 37:

Quote:
The XLR line outputs do not operate servo balanced! When connecting unbalanced equipment, make sure pin 3 of the XLR output is not connected. A connection to ground might cause a decreased THD (higher distortion) and increased power consumption!

XLR Pin 3 should be left open.
This is a bit non-standard, usually XLR Pin 3 is connected to ground in XLR-RCA cables and adapters.
A snipping tool can “convert” those.

Wait, so how exactly would I "leave it open"?

4 Reply by KaiS (edited by KaiS 2021-09-28 14:32:22)

  • KaiS
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Re: Using RCA for speakers and XLR for tubes at the same time?

exact wrote:
KaiS wrote:
exact wrote:

...If I get an RCA-XLR-cable to connect the tube-amp to the RME's XLR-inputs, I'm all good? The tube-amp that I'm currently looking to get only has RCA-inputs,
Just want to make sure I'm all good here.

Be sure to have the XLR cable wired according to the manual, page 37:

Quote:
The XLR line outputs do not operate servo balanced! When connecting unbalanced equipment, make sure pin 3 of the XLR output is not connected. A connection to ground might cause a decreased THD (higher distortion) and increased power consumption!

XLR Pin 3 should be left open.
This is a bit non-standard, usually XLR Pin 3 is connected to ground in XLR-RCA cables and adapters.
A snipping tool can “convert” those.

Wait, so how exactly would I "leave it open"?

• Open the XLR plug (turn the back part counterclockwise),
• From the front, press out the interior together with the cable (don’t pull the cable).
• Look at the solder side of contacs, there are numbers.
• Contact 3 (the middle one) should have no connection.
• Remove any possible connection made there.
• Don’t remove the screening soldered to contact 1!

• You should end up with:
Contact 1 = screen, goes to RCA housing.
Contact 2 = hot (+), thin wire goes to RCA center.
Contact 3 = cold (-), not connected.
XLR housing solder connection = screen or not connected, as connection to screen is made when the XLR is plugged in.

KaiS's Website

  • exact
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Re: Using RCA for speakers and XLR for tubes at the same time?

Oh alright, thank you very much for the detailed explanation!

  • Registered: 2022-01-02
  • Posts: 3

Re: Using RCA for speakers and XLR for tubes at the same time?

Hello KaiS,
Thanks for the explanation. Can you please refer to a cable that can be modified - or preferably, a plug & play ready cable?

7 Reply by KaiS (edited by KaiS 2022-01-05 21:57:43)

  • KaiS
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Re: Using RCA for speakers and XLR for tubes at the same time?

f.franken wrote:

Hello KaiS,
Thanks for the explanation. Can you please refer to a cable that can be modified - or preferably, a plug & play ready cable?

You get plug and play cables in pro audio / musicians stores if you ask exactly for this (show my posting).

Else it’s a bit of a gamble how the internals are soldered and if it’s possible to snip off a bridge to Contact No. 3 (the middle connector).
Neutrik XLRs are easy “twist to open” to have a look inside.

KaiS's Website

  • Registered: 2022-01-02
  • Posts: 3

Re: Using RCA for speakers and XLR for tubes at the same time?

KaiS wrote:
f.franken wrote:

Hello KaiS,
Thanks for the explanation. Can you please refer to a cable that can be modified - or preferably, a plug & play ready cable?

You get plug and play cables in pro audio / musicians stores if you ask exactly for this (show my posting).

Else it’s a bit of a gamble how the internals are soldered and if it’s possible to snip off a bridge to Contact No. 3 (the middle connector).
Neutrik XLRs are easy “twist to open” to have a look inside.

Thanks again. My new ProCab CAB705 cable is waiting to be converted for the ADI-2 DAC which i also have in house now.
I want to hook up my active subwoofer (Jamo SUB 210) to the RCA outputs and my vintage amplifier (Rotel RA-980BX) to the XLR outputs, with the converted cable. Is that 0K to do?
Alternatively, could i use RCA splitters to connect both sw and amp to the RCA outputs?

9 Reply by KaiS (edited by KaiS 2022-01-10 08:49:00)

  • KaiS
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Re: Using RCA for speakers and XLR for tubes at the same time?

f.franken wrote:
KaiS wrote:
f.franken wrote:

Hello KaiS,
Thanks for the explanation. Can you please refer to a cable that can be modified - or preferably, a plug & play ready cable?

You get plug and play cables in pro audio / musicians stores if you ask exactly for this (show my posting).

Else it’s a bit of a gamble how the internals are soldered and if it’s possible to snip off a bridge to Contact No. 3 (the middle connector).
Neutrik XLRs are easy “twist to open” to have a look inside.

Thanks again. My new ProCab CAB705 cable is waiting to be converted for the ADI-2 DAC which i also have in house now.
I want to hook up my active subwoofer (Jamo SUB 210) to the RCA outputs and my vintage amplifier (Rotel RA-980BX) to the XLR outputs, with the converted cable. Is that 0K to do?
Alternatively, could i use RCA splitters to connect both sw and amp to the RCA outputs?

Although both variants do work, using separate outputs is preferable.

Switched off electronics can cause (minor amounts of) distortions.


If your new cable isn’t easily moddable by cutting a connection, get yourself a soldering iron and some electronics solder and learn how to DIY.
Neutrik XLRs are easy to solder, a good starter.

KaiS's Website

  • Registered: 2022-01-02
  • Posts: 3

Re: Using RCA for speakers and XLR for tubes at the same time?

ProCab XLR plug converted by means of my old soldering iron and latent skills. Everything works fine; thanks for the tips & tricks.

  • Registered: 2022-01-12
  • Posts: 6

Re: Using RCA for speakers and XLR for tubes at the same time?

Hi there, have you got your tube-amp already?
Wondering why don’t you get one with XLR inputs to fit the ADI-2?
I am currently using speakers connected to ADI thru RCA to a Marantz amp, and a Chinese made tube-amp connected to ADI thru XLR cables. It works well, although I can hardly tell the difference compared with using the ADI-2 headphone amp directly.
But with a tube-amp, you can have fun with changing tubes.
All the best.


exact wrote:

So currently I run my ADI-2 DAC with a speaker-amp connected to it via RCA. I use HD800 straight from the RME. But I was thinking of getting a tube-amp to try with my headphones. If I get an RCA-XLR-cable to connect the tube-amp to the RME's XLR-inputs, I'm all good? The tube-amp that I'm currently looking to get only has RCA-inputs, same goes for my speaker-amp.

I get that the audio will play on both RCA and XLR at the same time, but that's easily solved with just turning my speaker-amp off while using the tubes, yeah?

Just want to make sure I'm all good here.