How to Connect Headphones to a SMSL DAC

I use a Singxer SA-1 amp with my Hifiman Arya Stealths and it sounds fantastic. It’s a fully-balanced Class-A amp that’s nice as I believe your DAC is also fully balanced, and here’s a nice used one you can get for $398 (a $200 discount). Can’t really go wrong with this one.

https://www.usaudiomart.com/details/649999098-sa-1-headphone-class-a-amplifier-pre-amp-excellent-condition/

@soix Thx!  I’m not sure about connectors.  Would I use the balanced out from the DAC to the balanced in on the Singxer?  Right now my powered subs are using the balanced out on my DAC.  Could I instead plug them into the balanced out on the Singxer? (My powered speakers are connected to the RCA out on the DAC.)

Yes, I’d use the balanced out from the DAC to the balanced input on the Singxer as they’re both fully balanced.  You’ll want to use the fixed output on the DAC (that disables its volume control) into the amp and just use the Singxer to control the volume.  I thought this was a headphone setup so not sure how the subs figure into this — you’d have to provide more info about what you’re doing here. 

Here’s my system.  I have a NODE N130, but I’m bypassing the internal DAC.  A USB cable connects the NODE to a SMSL M400 DAC.  The M400 has 2 RCA outputs, these are connected to my 2 powered B&O speakers.  The 2 balanced outputs on my M400 each connect to one of my powered subs.  There’s no more outputs available.

So say I bought a Singxer, I would install interconnects between the balanced outputs on my M400, and the Singxer balanced inputs.  Having unplugged the 2 subs, I don’t know where I would reconnect them.

‘Right now I’m using my iPad to control the NODE, but volume is controlled by a remote for the M400.  You mentioned that the Singxer would control volume.  I would be using my system for both headphones and my speakers.  I don’t understand if my speakers/subs need to all connect to the Singxer, or if those stay connected to the M400.  And then, how do I switch between listening via the headphones and the speakers.

‘All this does point to the utility of the NODE, where everything is in one box and controlled by one controller.

Well, I wish I was aware of the rest of your setup going into this because it changes a lot. Here’s what I’d do if I was you. If I’m listening to home audio just leave things as they are if it’s working for you. To switch to headphones just unplug the cables that go into the subs and plug them into the Singxer and switch the DAC from variable to fixed output (so only the Singxer’s volume control is operative). And if you go this route use a good balanced headphone cable into your headphones if you don’t already have one to preserve the balanced connection. It’s not the most elegant or seamless solution, but it’s not really hard to do and it’ll work and you’ll get all the goodness of the SA1 (and your DAC) into your ‘phones. I have a balanced headphone cable recommendation if you’re interested. Sorry for the convoluted answer (it sounds worse in words than it would be in practice and would only take a minute to change over), but I didn’t know all the other stuff you had going on here. You’ve got good headphones and they’ll reward you for the effort, and if you decide to upgrade headphones in the future your electronics will scale up nicely and let them sing.