Balanced XLR

[Kubs]

Thought I would make use of the balanced xlr connection between my amp and DAC. So, I went to my local music instrument shop and purchased 2 xlr cables at £5 each ... I wasn't expecting much in difference between rca and xlr but I was wrong ... It was like removing a duvet from the area where the music was coming from ... I was able to switch between rca and xlr from the amp remote allowing me to do a rapid comparison ... If you have a balanced xlr option available please make use of it ... I found it revelatory.

 

[davedotco]

you do realise that the MDac uses unbuffered outputs, don't you?

 

[Kubs]

I don't understand, Davedotco?

 

[davedotco]

I don't understand, Davedotco?

Nobody understands Davedotco.......*dirol*

If you use both outputs on the MDac at the same time, they will interact with each other, the balanced output may no longer be symetrical due to the effect of the loading on the +ve rail of the balanced output by the loading on the unbalanced connection.

 

[Kubs]

I see ... So i should disconnect the rca ... ?

 

[davedotco]

I see ... So i should disconnect the rca ... ?

Use either output, not both. The design is cheapskate, the two legs of the differential amplifier drives +ve and -ve on the balanced out and the same +ve leg of the amplifier drives the unbalanced out.

The loading on the +ve and -ve legs of the balance output is therefore different, the +ve leg 'sees' both the balanced and unbalanced impedance, the output of the +ve and -ve legs of the balanced output will be different, not good.

 

[andyjm]

If you have a balanced XLR option available please make use of it ... I found it revelatory.

As a general rule for normal short runs of cable in home hifi systems there is no benefit in using balanced connections - and there are potential disadvantages. That's not to say that in your case balanced doesn't sound better - perhaps who ever designed the output stages of your DAC or input stage of your amp made a better job of the balanced connections.

It would be wrong however to assume that is true of all systems. A bit like saying 'I have a red car, and it goes well, therefore all red cars go well'.

Edit: Dave's point is relevant as well, cant be too specific without knowing the circuit topology, but it is possible by having both connections in at once it isn't a fair comparison.

 

[ID.]

Not that I've ever used XLR, but my understanding is that balanced outputs use a higher voltage as well, so this would have an effect on the volume (you would hit the same volume earlier?) which would also impact on one's perception of the sound. Or perhaps I've completely misunderstoof/misremembered something.

 

[unsleepable]

Not that I've ever used XLR, but my understanding is that balanced outputs use a higher voltage as well, so this would have an effect on the volume (you would hit the same volume earlier?) which would also impact on one's perception of the sound. Or perhaps I've completely misunderstoof/misremembered something.

This also depends on the amplifier. Bryston ones for example have the same sensitivity regardless of input, so all other things being equal they will sound louder on balanced inputs than on unbalanced ones. The rear switch can be used to make them equivalent. Others like the Arcam P49 have different sensitivities, and they sound equally loud using the balanced inputs with double voltage.

I don't know how the Musical Fidelity M6500i goes about this.

 

[Kubs]

Whatever is going on, it sounds great ... 🙂