Its been a while since I have posted any DIY stuff, but I have been tinkering in the background. The latest project is still a bit premature to be thrown out into the wild, but still....
Anyway, a friend who knows my bent for audio electronics sort of challenged me to build him a quality DAC and headphone amp (separate boxes) that could rival commercial gear at a sensible price. Of course I took the bait I need an analogue input headphone amp for myself anyway....
This is the initial DAC box, a second is being made (for my friend) is about a 1/3rd less tall and looks sleeker with brushed front plate. The headphone amp box will match.
DAC is powered from USB,HPA will be from a wall wart.
Measurements. Im only going to post a few as Im still tinkering.
DAC output 1 kHz 0dBFS. Maybe not SOA, however pretty damn good. Note that the noise floor is in reality lower, this is an artifact of the measurement system. I need to build a notch filter which takes out the fundamental and it will drop about 20dB.
headphone amp with no load, same DAC feeding.
With my Oppo Planar Magnetics (32 ohm load) plugged in. SPL was 108dB ouch!
No thats not an error, its the correct plot. Barely no change in distortion. I need to find some high impedance cans to test now.
DAC -60dB
12kHz jitter (HPA output measured)
No, Im afraid Im not going to reveal the secret sauce quite yet
I will send it to @amirm when finished for some serious testing on his AP.
Oh yes, it does actually sound pretty good too !
Anyway, a friend who knows my bent for audio electronics sort of challenged me to build him a quality DAC and headphone amp (separate boxes) that could rival commercial gear at a sensible price. Of course I took the bait I need an analogue input headphone amp for myself anyway....
This is the initial DAC box, a second is being made (for my friend) is about a 1/3rd less tall and looks sleeker with brushed front plate. The headphone amp box will match.
DAC is powered from USB,HPA will be from a wall wart.
Measurements. Im only going to post a few as Im still tinkering.
DAC output 1 kHz 0dBFS. Maybe not SOA, however pretty damn good. Note that the noise floor is in reality lower, this is an artifact of the measurement system. I need to build a notch filter which takes out the fundamental and it will drop about 20dB.
headphone amp with no load, same DAC feeding.
With my Oppo Planar Magnetics (32 ohm load) plugged in. SPL was 108dB ouch!
No thats not an error, its the correct plot. Barely no change in distortion. I need to find some high impedance cans to test now.
DAC -60dB
12kHz jitter (HPA output measured)
No, Im afraid Im not going to reveal the secret sauce quite yet
I will send it to @amirm when finished for some serious testing on his AP.
Oh yes, it does actually sound pretty good too !
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