TOPIC:

Hello, sorry if this has been asked already. I see that the software plugins for the 2x4 (and HD) offer the option of inverting the absolute phase of each output. Has anyone tried using this feature to provide balanced output from the board (or box)? I know the connectors are incorrect, but I have an OEM application anyway, so I'd be using the board inside of my own box.

What I mean is, if you don't use the crossover at all (bypassed), are there any possible issues with configuring the board to provide inverted outputs on #2 and #4 (and non-inverted on #1 and #3), thus providing balanced output for two channels? Thanks.

Sure, it's possible to create a configuration as you say. You just need to make sure that it's exact same latency/processing in both path (i.e. don't put more PEQ on one of the inverted channels than the non inverted..

DevTeam

Thanks for you reply.

So, if the processing on each output channel is identical, can I assume that the latency is identical also? Any difference would affect the phase.

Also, obviously, the levels have to be matched as well. Can I also assume that if they are set the same in the plugin, that they would be identical on the outputs?

What is the tolerance on the output impedance to ground for each channel? Thanks.

I need to decide if I need an audio transformer to make sure that the two signals are balanced.

We've actually never tried this setup you're trying to do here.. We're guessing it would work..
Doing an electrical balanced output would be the best way for sure. But worth trying if the software version work. Just need to have levels and processing the same.

HTH

OK, great, thanks for your reply. I guess there's only one way to find out: try it.

Hello dirkwright,
Have you tried to do the "balanced software solution" that you describe here ?
Is it working ?
Thanks,
Loïc

Howdy dirkwright,

Thanks for your post, i was just considering something similar, i.e. applying the miniSharc (in 2x8 config) or the nanoDigi 2x8, processing 4 inverted and 4 non-inverted signals on each board, to create 4 balanced outs per board. Those in turn would feed 4x2 (both IN&OUT) on a DAC8, This way i could create balanced DSP for an active four-way stereo speaker pair (containing a total of 8 balanced power amps), by using one 2x8 DSP board and one DAC8 per four-way speaker.

Given the above i was curious if you got around to testing balanced application of the SE 2x4/2x4HD yet?

Thanks for any input, gtz from Amsterdam, Yuri

No, I'm sorry, but I have been busy with other projects for a long time now. I have not had time to explore this any more. Good luck to you.

Old thread, but still relevant. Thought I'd try using my 2x4HD to create a balanced line out. Having a bit of trouble getting it to work. Hoping someone can help.

Starting with the DSP set-up, inputs, routing (levels 0dB, all DSP bypassed):

Now the outputs (levels 0dB, all DSP bypassed except INVERT channels 2 & 4):

Correct so far? Here's the wiring for my custom 3-pin XLR cables. I think I did this right, but could use some advice from someone more familiar with how balanced lines work:

Problem: When I plug in the XLR cables to test, I hear L & R output from the amplifier, but it's acting like single-ended, not balanced input.

Symptom: When I make any changes to outputs #1 (left -) or #3 (right -), it has no effect on the amplifier's output. I can invert, mute, change levels, or unplug either #1 or #3 (or both) and nothing changes. However, when I make changes to outputs #2 (left +) or #4 (right +), it reflects in the amplifier's output, as if using single-ended inputs.

Observation: Swapping RCA plugs #1 and #2 results in no change. Swapping RCA plugs #3 and #4 results in no change. This seems to indicate all MiniDSP outputs are functioning. The fault moves with the (-) side RCA cable for both left and right channels.

I haven't ruled out the fault being inside the amplifier, but felt this was unlikely. The amp functions perfectly in single-ended mode (input & output are independently selectable for SE or balanced operation).

Thanks in advance for any advice, suggestions.

@AAsearless,

From what we can tell from your plugin and diagram, everything looks pretty good. Maybe try to double-check if you have got all the soldering right on the XLR end?

DevTeam

Thanks for taking a look at my set-up. Good to know the plug-in settings are correct.

I did a continuity test (twice) on the RCA to XLR cables:

Strange it isn't working. Seems the amplifier could be the problem.

I wanted to cap this thread off for anyone else that may find it after some searching.

I'm using the MiniDSP 2x4HD and this technique DOES indeed work, in fact, very well.
I think the key may be using the Output 1/3 and 2/4 output pairing for FL+/FL- and FR+/FR- respectively instead of the Output 1/2 3/4 described here. I think there was another thread somewhere that noted the 1/3 2/4 configuration as well.

I constructed my own RCA/RCA to XLR cables exactly as shown here.

I'm feeding the MiniDSP 2x4 HD USB signal from a laptop and outputting from the DSP to a PS Audio HCA-2 amplifier. It sounds EXCELLENT.

Hey, thanks for the feedback.

So you're saying to use the following?
OUT 1 for Left (+)
OUT 2 for Right (+)
OUT 3 for Left (-)
OUT 4 for Right (-)

Which outputs would be inverted in this set-up? 3 and 4?
I'd need to rearrange my RCA cables on the HD2x4, right?

Thanks,
Aaron