This is the finished amp complete with my fingerprints.
I still only have about 8 hours listening on it, so it’s really still just a preliminary impression, I’ll keep listening, and if my overall impressions change I’ll update. But my ZMF Eikons arrive tomorrow, and while I will listen to the ZMF’s on it along with my other amps, it might be a week or two before I get back to “listening to the amp”.
The bulk of listening was done as follows Amazon Music HD -> USB -> Gungnir Multibit -> Whammy -> Focal Elex. I did try a number of other heaphones, the whammy had no problems driving any of them including the T50-RP2 (11 on the volume dial, so plenty of headroom).
I built mine from the Kit supplied by DIYAudio, the kit is complete (minus a chasis) and they are high quality parts. You’ll want to sort and label the resistors before starting, with my aging eyes and the tiny text, that required magnification and about 45 minutes.
The build itself is straight forwards, you can build the power supply section in 3 different ways, and all of the parts for all 3 are in the kit (the build guide covers these), you will have components left over when you are done. I used the LED reference design, so I ended up with some extra resistors.
The build guide has you build and test the PSU first, that’s what I did, after that it’s pretty much put the components in the right holes, the only thing you don’t populate is the isolation caps in the feedback circuit. Note that the power circuit is dealing with mains voltages, and you need to be comfortable with that.
I used a Hammond 1455T2201BK enclosure, it’s basic, the circuit board is designed to slide right in, you need to ensure you drill the hole for the volume pot in the right place, and cut the hole for the IEC socket slightly above the center line (I think mine is offset 2mm vertically), so it can’t interfere with the resistor it’ll end up being close to. I like the amp enough I’m considering making up a custome facia for it.
Total build time for me was about 4 hours to put everything on the board, another 3 maybe messing around with the enclosure, but I 3D printed test plates to ensure I had clearances, if you just used paper templates, it’s probably an hours worth of work to cut the holes and finalize the I/O wiring.
The Amp takes a long tiome to get to a stable temperature, the Voltage regulators get hot, the FET’s in the amplifier, not so much, I left it on overnight, and it stabalized at about the same temperature as the Gungnir.
The noise floor is pretty good, there is a slight audible hiss when the volume knob gets past the 3 oclock position with no input, given most of my listening was closer to 9 oclock, it’s not really relevant.
Overall I really enjoy listening to the amp, it’s a very Neutral/Natural sounding amp, with perhaps a hint of warmth.
I like the tonality, bass has impact and control, the trebble has good extension, but isn’t fatiguing, and I liked the timbre on vocals.
The dynamics were also a standout for me, it resolves details really well without shoving them in your face.
It’s a really good sounding SS amp, better than any other SS I own, which is limiting my ability to give a complete review.
If your comfortable building the amp, and you don’t need the additional features they provide, I’d take the whammy over a Jotunheim, or any of the THX amps I’ve heard, how it competes with higher end SS amps I can’t really say, because I just don’t have a reference.
I do still prefer my Liquid Platinum, but it’s not a very interesting comparison. It’s a tube hybrid, and it’s balanced out of the Gungnir, which does make some difference. I just prefer the additional body and warmth the tubes impart and the increase in soundstage the LP provides.
Link to the DIY Audio page, includes links to the build guide.
Wayne Colburn talking about the design of the amp.