Balanced Buffer Needed with a Balanced Volume Control?

[DualTriode]

Hi All!

I am trying to pick the correct forum to place this post in?

I am a little slow to the party; I just bought a Cambridge Audio DacMagic DAC box. My question is about the balanced line level output of this thing.

First stop is to connect this thing to a balanced “pro audio” SS power amplifier. Will a passive balanced volume control (passive line stage) work or do I need something like a balanced B1 buffer in there too?

Suggestions? Recommendations?

DT

 

[clm811]

Balanced B1

Hi.

I also bought a DacMagic with balanced outputs and am building a balanced B1
from imported boards(see pic). You'll need two stereo boards plus a 4-gang pot.

I look forward to using this combo to drive a Forte power amp with balanced inputs.

-Chas

 

[clm811]

Just finished final assembly,

Everything works, exept for a defective 4-Gang Attenuator (from China on eBay) I am contacting the vendor to see about a replacement, but it's way past the 14day return period...

I wired it up with a one stereo pot on each channel, and the sound with CD's is GLORIOUS!

I've just ordered a 24bit/192kHz USB to SPDIF adapter, so I can listen to my PC.

-Chas

 

[AndrewT]

fit a bal to unbal input transformer to your amplifier.

 

[DualTriode]

Hello clm811,

Nice project, your Balanced B1 Buffer.
Did you try the passive approach, without the B1 buffers, with only the ganged attenuators between the DacMagic output and the power amplifier input?

DT

 

[clm811]

Did you try the passive approach, without the B1 buffers, with only the ganged attenuators between the DacMagic output and the power amplifier input?

Thanks for the kind words.
Nope, I was concerned about input/output impedance, so I went with the buffered approach.

The sound is quite nice and I don't find myself wanting to turn down the volume as much as before(lower distortion?)...

-Chas