SeNNator

Now that my hammond case has arrived. My bundle of wires and boards now looks far tidier:




In honesty, the amp still makes the HD650 sound like a HD650, but with that little extra on both ends of the frequency range. It's a sound I thoroughly enjoy!

Unfortunately the potentiometer is wired backwards (anti-clockwise for Volume+) , but since it's just me using it I can ignore that.

Just swap the outer connections on the volpot and this too will work 'normally'.
The excess 'warmth' should be gone .... a touch of warmth should remain.

If you want you can shave that warmth off by using the values for the 'old pad' version.

Being one that has elementary reviewing skills I shall explain it as thus, in comparison to my O2 amp:

The HD650's sub bass response has improved noticeably. The bass doesn't fight for attention, but you can feel the headphones dive right into it when the music allows. The first time listening to it dive into such deep bass was a very, very pleasant moment.
mids feel "cleaner" and more controlled. This sounds weird for a HD650 that is known for it's brilliant mids, even more so when it's driven by the analytical O2, but the toned down mids of the SeNNator improved upon it's presentation (better words pending).
That said, the lowered mids has given space for the highs to present itself with less "obstruction" so to say, and micro details start to creep in here and there in some music I listen to.

It's a "balanced out HD650" yes, but I wouldn't call it neutral, and I certainly would not say that the amp has taken anything away from the HD650's.

Just received my Geek Out 450 DAC/amp and I am impressed. So I thought why not try it with the Schiit Wyrd. Real improvement. So I thought why not run the Geek Out/Wyrd into the SeNNator? The best I think the HD650's have sounded. The whole chain seems to have synergy. The microdetail of the 650's has improved, and the bass and sub-bass are even better controlled. Been listening for hours. No listening fatigue, but not smoothed over or syrupy. Bad recordings are bad and they are fatiguing at times. Instruments sound even more real than before and they were already very good. This setup is just drawing me into the music. The best thing is I am getting all the musical information, but I don't seem to have to turn the volume up as high to get the 650's into their "sweet spot". Great! Didn't realize how the sub-bass adds to the emotional impact of the music for me.

Edit: Oh my gosh! I just looked up and the Sun is coming up. I have been up all night listening to music .  Good thing I don't have work today!

Is different to be out of sync with most everybody else. Today was strange. Slept from about 11:30 am to 2:00 PM now I am awake again. Hope I don't do this regularly. I'm not working nights, just on holiday. Guess that's what they are for.

The thing I like best about the Geek Out's DAC is it plays FLAC files up to 24/192 directly from the USB port, well now on the Wyrd. Very versatile and switches no problem from one file format to the other, no sound or delay. Can't believe it's so small.

Yes, it is a single phase rectifier (when you mean the power supply schematic in the 3rd post)

The reason for that is that he wanted to use a single winding 15V AC adapter for a power supply.
There is nothing wrong with single phase rectifiers in low wattage power supplies though, not recommended for power amps.

The SeNNators I built both have a DC input and DCDC converters that create dual rail voltages.