Building DAC with lineout and headphone out

[XDVD]

I'm making a DAC using a DIYINHK AK4493EQ (768kHz/32Bit AK4493EQ DAC BARE PCB, I2S/DSD input - DIYINHK). It sounds great right now with the lineout. I've probably committed a sin and have wired up headphones directly to the lineout and run at cut volume.

I have dual +-12V (could up to 15V too) rails using a variety of op-amps (opa2134, ad8620, etc.). I haven't been rolling op-amps yet.

What's the recommendation for adding a headphone amp or headphone out? I have a lineout going to a tube amp currently that I am very happy with. I'd like to add a headphone out.

I'd ideally solve for low-impedance IEMs (massdrop plus universal IEMs) as well as higher impedance cans.

Should I go with a single pole 4 throw setup and switch between two lines? If the single op-amp is able to drive sufficient volume

 

[abraxalito]

A line out works fine as a headphone out provided there's enough current available. If your output opamp is a dual then consider getting an adapter sporting an OPA1622 like this : OPA1622 Dual OPA DIP8 (Unit) - Audiophonics


Note the 0V pin on one of these is 'virtual' (created by two resistors from the rails) so a wire explicitly grounding the node probably is an improvement.

 

[XDVD]

Thanks for the feedback. Will order.

If I wanted both a headphone out and rca lineouts in the back that could be left hooked up to my tube amp does that change any recommendations?

 

[Markw4]

The OPA1622 adapter boards without a real ground pin will produce more distortion than a properly connected OPA1622. It may be possible to run a short length ground wire from the OPA16322 ground pin to mainboard ground. One guy did that and measured considerably less distortion. Ummm...using a resistor voltage divider between the power pins as an approximate ground is not really the best solution, IMHO.