Driving multiple amps with DirectStream DAC


#1

In short, does the DirectStream have beefy enough output stage to drive a power amp (Zin 25K ohms) and a pair of stereo subs (10K ohms) with y-splitters on the RCA outputs?

The manual strongly recommends bypassing a preamp if possible, stating that the outputs are “high-current”. However, I know that putting a load on both outputs (RCA & XLR) simultaneously is a no-no.

So, how about this use case - amp + subs? Does the DirectStream have enough oomph to do a good job at this or is an active line stage warranted? (I don’t own one currently or I’d try it.)

Relatedly, does the DirectStream’s output current stay constant regardless of volume setting?


#2

The 20dB attenuator is a 15 Ohm shunt to ground - no pair of amps is going to be that much of a load :)

The real issue with a Y and multiple interconnects is the potential for extra noise from groundloops, etc. not the output current of the DS.

The manual is referring to using both the RCA and the XLR outputs at the same time - in that case using the RCA will unbalance the XLR and you can potentially loose some common mode noise rejection compared to just using the XLRs. On the other hand many systems don’t have enough noise to worry about.

The bottom line is that the output of the DS has the same frequency response whether loaded by 100k Ohms or 15 Ohms - it’s only the overall level that changes (by design.)


#3

Thanks! By my calc I am driving a 7K ohm load with the two loads in parallel which should be no problem at all from what you’ve said.

Mind you, this is what I’ve been doing, and the sound is fantastic; I was just a bit concerned that someone would tell me it couldn’t possibly be great. :)


#4

I use both outputs of my DS to drive a multi amped rig. I can’t tell a difference in the performance of the balanced with the unbalanced in/out of the loop. Some have, however. It just seems to work in my system regardless of the technical issues.


#5

i also have been using both outputs, with the RCA’s connected to a pair of poweres subs. After disconnecting the RCA I feel it sounds better, and with so much bass it almost doesn’t need the subs. I will try the experiment again and puts the RCA’s back in. I even bought cheap XLR splitters this weekend and will have to see how it sounds that way.

Im not sure how to proceed to achieve my goal having the mains not produce I to the 30 ha range. I may consider multi dacs and use a high pass filter in Jriver or I may even try plugging the ports of my mains to get less low bass, and let the subs handle from 40hz on down.