[James Tanner]

  I am putting together my Hifiman HE-6 setup.
 
Can I leave the Balanced Outputs (in the back) connected to my Bryston 4B-ST if I am listening to either Balanced or Unbalanced headphones?  I don't mind disconnecting the headphones when using the preamp section but I would prefer not to disconnect the XLR cables in the back.
 
I will be using the BHA-1 as a preamp into the 4B-ST to drive the HE-6s.  However, I really like how the Grado RS1is sound from the headphone amp.  The amp section drivers the HE-6s okay but I think I would choose the HE-500s with my WA6-SE.
 
I am expecting my HE-6s driven by the BHA-1 and 4B-ST to be close to my endgame.

 
Hi
 
Yes you can leave the rear XLR's connected.  In fact the BHA-1 is capable of driving all the connections at once if needed.
 
Enloy!
 
james

 

[Trance_Gott]

I have a question. My HE6 has a cable with 4 pin XLR plug. I created a adapter from 4 pin to 2x 3pin XLR to connect my HE6 to the XLR output of my Phonitor 2 on the rear side. I tested this cable with the BHA1. When I connect my HE6 via adapter on the rear of the bryston the sound plays a lot lower then the connect to the 4pin XLR on the front. With my Phonitor2 it is the same. The front 6,35mm plays a lot louder then the 2x 3pin XLR on the back. Why? Is the impendance of these outputs a lot higher then the plugs on the front?

 

[James Tanner]

Hi 
 
All the outputs are in parallel so we feel the adapter may be mis-wired.  
 
james

 

[Trance_Gott]

1x NC4FXX-B to 2x NC3FXX-B

4-pol:
1- left +
2- left -
3- right +
4- right -

3-Pol:
1- Ground (not used)
2- Channel +
3- Channel -

 

[bfreedma]

James,

You might want to edit your post above to obfuscate the email address.
Unless you want Mo to get a lot of spam, in which case, disregard.

 

[James Tanner]

1x NC4FXX-B to 2x NC3FXX-B

4-pol:
1- left +
2- left -
3- right +
4- right -

3-Pol:
1- Ground (not used)
2- Channel +
3- Channel -

HI 
 
Looks good - not sure what is going on.
 
james

 

[Rob80b]

  Hi 
 
All the outputs are in parallel so we feel the adapter may be mis-wired.  
 
james

 
 

1x NC4FXX-B to 2x NC3FXX-B

4-pol:
1- left +
2- left -
3- right +
4- right -

3-Pol:
1- Ground (not used)
2- Channel +
3- Channel -

Hi Trance
 
I’m with James on this one, your wiring scheme is correct but I’d double check to make sure you have indeed soldered all the wires to the correct pins, happens to the best of us, twice I crossed wires on my 4 pin adapters even after triple checking.

 
Due to the close proximity of the headphone drivers to the ears, unlike speakers, correct polarity may not be totally obvious  but phase cancellation will and is noticed as a drop in volume output.
 
Robert

 

[Rob80b]

Also, I’ve brought this up before, if one is making reference to the BHA-1 manual the diagram is showing the pins from face on (front) and not the side to solder the wires so remember to reverse the order when soldering, all too easy to get distracted from the correct order.
 
http://bryston.com/PDF/Manuals/300028%5BBHA1%5D.pdf
 

 
 
Or just use these diagrams.
 

 

[Trance_Gott]

Thank you!
I don't have solder the wires self. I will contact the electrician which solder it for me.

 

[Rob80b]

Hi Trance
 
If you try both connections see if the 3 pin adapters sound as clearly defined with regards to stereo imaging and bass, if not, that would be a tell tale sign that one of the 3 pin XLRs has the wires reversed.
 
Robert

 

[James Tanner]

  I have a question. My HE6 has a cable with 4 pin XLR plug. I created a adapter from 4 pin to 2x 3pin XLR to connect my HE6 to the XLR output of my Phonitor 2 on the rear side. I tested this cable with the BHA1. When I connect my HE6 via adapter on the rear of the bryston the sound plays a lot lower then the connect to the 4pin XLR on the front. With my Phonitor2 it is the same. The front 6,35mm plays a lot louder then the 2x 3pin XLR on the back. Why? Is the impendance of these outputs a lot higher then the plugs on the front?

 My apology - From Engineering:
 
 
Yes he is correct.
The rear output has 50 ohms isolation resistors in series with the signal  and is not expected to drive headphones only line inputs 10k ohms or above.
This is easily modified if necessary. NOTE: The an overall load impedance on theBHA1 should not be less than 16 ohms. 
 
Stuart

 

[Rob80b]

   My apology - From Engineering:
 
 
Yes he is correct.
The rear output has 50 ohms isolation resistors in series with the signal  and is not expected to drive headphones only line inputs 10k ohms or above.
This is easily modified if necessary. NOTE: The an overall load impedance on theBHA1 should not be less than 16 ohms. 
 
Stuart

Thanks Stuart...James
 
Good to know

 

[Trance_Gott]

   My apology - From Engineering:
 
 
Yes he is correct.
The rear output has 50 ohms isolation resistors in series with the signal  and is not expected to drive headphones only line inputs 10k ohms or above.
This is easily modified if necessary. NOTE: The an overall load impedance on theBHA1 should not be less than 16 ohms. 
 
Stuart

Thank you for the info! Yes this makes sense now.

 

[CanadianMaestro]

   My apology - From Engineering:
 
 
NOTE: The an overall load impedance on theBHA1 should not be less than 16 ohms.   
Stuart

I didn't know this. Many thanks. I've never used headphones/IEMs with less than 16ohms Z, but I shall avoid doing so.

 

[Funkehed]

. When I connect my HE6 via adapter on the rear of the bryston the sound plays a lot lower then the connect to the 4pin XLR on the front.

Am I reading it right? You are connecting the headphones to the pre-amp outputs of BHA-1 on the back panel? BHA-1 has only one pair of 3-pin XLR headphone outputs, they are located on the front panel.