So I got a 5K and M4 in the last two days to try out. All testing is on Ubuntu 21.04. So the M4 is going back. The M4 and the 5k sound very similar on the headphone out. I only heard the difference slightly on the Koss KHP30i Ultras. On those I favored the 5K. Both sound very good on my MMX 300’s. The 58X is a little less exciting on them. Hoping a balanced cable will improve them on the 5K. I didn’t check the mic quality on the M4 as I need an adapter. The mic in on the k5 is very good. People commented right away with the MMX’s boom mic. I love the auto switch from usb int/dac/amp to bt on the fly. It really is a great device. I would love a $200 version with a great knob for volume on the top and maybe optical in? Slightly stronger amp and a preamp output… You listening Qudelix?
So why am I bailing on the m4? Everyone is right the build quality is great. It shows up as front and rear stereo in ubuntu. It is a beautiful thing. So my desktop monitors are Vanatoo T0’s. Normally with a sub but not for this test. I usually source the vanatoo’s from a Schiit Modi 2. I prefered it to both the usb, optical and the bt input on Vanatoo. But the M4’s dac sounds really cool on them with no eq. So much that I totally prefer the optical interface to the M4’s monitor out. And of course the M4 for me was going to be a killer preamp with dual volume controls. But in this case it just doesn’t do it for me.
I might still try the Hel 2. I loved the feel of the device at the Schiitir. And of course the Asgard 3 was similarly beautify feeling and sounding. Both are on a 4-6 week back order.
5K is a winner regardless. Everyone should own one. The feature set is just too good.