How to test multiple DAC/amp combos without the delay or switching between them?

What is the best way for me to A/B test a particular DAC/amp combo? I feel like by the time I unplug the headphones and switch devices, my audio memory is already fading.

Say I have a Modi / Asgard 2 plugged into one USB port of my PC and a Bifrost Multibit / V200 plugged into a different USB port and that I have them both carefully volume-matched for a particular set of headphones...

Can I somehow have the headphone output from both Asgard 2 and the headphone output from the V200 both going into some sort of switchbox that has a single headphone output to my headphones?

That way I could change PC output devices from Modi to Bifrost Multibit in Windows and simultaneously hit a button on the switch box to change which amp is outputting to my headphones.

Or is there a better way?

 

You could use something like http://www.amazon.com/gp/product/B00DAXINYO and some RCA to 1/4" adapters to achieve what you want. Might be easiest to use Foobar/Jriver configured to output to both of your DACs simultaneously, that way the only switching your doing is the switchbox to determine which amp feeds the headphones you're listening through.

 

JRiver will let you play a single stream to multiple outputs...pretty cool for this.

 

Oh, I had no idea I could run multiple USB DACs at the same time. Possible with foobar?

 

You could also grab a VB-Audio virtual cable splitter and output to two places at once:

http://vb-audio.pagesperso-orange.fr/Voicemeeter/banana.htm

 

In JRiver you create two zones which output to their respective dacs (you can also do all sort of dsp for each zone), then activate the "link zone" feature which essentially slaves one zone to the other in terms of what gets played.

There's *probably* an add-on in foobar somewhere that can do that, but I don't have experience with that...

 

My suggestion is not really to quick A/B but play a whole playlist, and close your eyes and really sink into the music. After that try making the switch, you might find that much easier to do.

Virtual Audio cable and multiple usbs plugged in is really not a good idea, you could get ground noise and jitter and other nasties that you might not be aware of creeping into the system.

If you wanna A/B I highly suggest using 2 seperate laptops/systems.

 

This is the most important thing. Don't compare, just listen to how it makes you feel and what stands out. Then do it with DAC B. Then A, then B. After you start to understand how each feels, then, not while listening, compare in your head. If you try and listen for the differences and compare while listening, you'll trick your brain.