SOLD: Mass Kobo Model 394
For Sale
Shipping Destinations
  1. North America
Or Best Offer
Oct 17, 2018 at 3:43 PM Thread Starter Post #1 of 8


500+ Head-Fier
Oct 31, 2016
Boston, MA
(sold pending payment)Up for sale is one of the best solid state amps ever made - the Mass Kobo Model 394. This is an mk1 version and I am the first owner. Cosmetically there are some scratches on the black top piece and a nick on the top left corner of the faceplate.

Recently got a checkup with Mr. Mass and is in perfect shape sound wise. Comes with the stock power cable. No box though. I'm selling mine because a friend asked me to help sell his 394 mk2, and I decided to keep his mk2, even though sonically they are identical except for the balanced input gain switch. Looking for $3,200 all in including Paypal fees and shipping to within the US.

A few words on the 394, since it's a bit of an exotic amp here:

- It's a fully balanced design with a phase splitter for balanced out with SE input. The XLR input defaults to a low input gain on the mk1 which was replaced with an input gain switch on the mk2. The power supply is custom built in Japan and takes 100-240v plug-and-play. As a consequence of not using a linear power supply the 394 is more sensitive to dirty power than the GS-X mk2, though.

- I've extensively demo'd the GS-X mk2 and IMO the 394 compares favorably to the GS-X mk2. The GS-X mk2 is very fast, bright and clean, but the 394 is at least as good resolution-wise and much more composed. Treble regulation is noticeably improved and the 394 is a bit more punchy in the bass. IMO the GS-X is great at giving thicker sounding headphones an "edge" but can be a bit shouty with less warm cans and really hard to drive ones. If you've tried the Mass Kobo 404, the SQ is similar but the 394 is a vast improvement in resolution, control and power.

- The comparison to the Liquid Gold is an interesting one that can go both ways. The Liquid Gold is a little less authoritative, thicker, and just a tiny bit more grainy than the 394. But the CALG excels at lower-mid and in particular mid presentation where the 394 might be a bit too restrained and polite. For classical music and Japanese vocals the 394 wins but I think I'd go with the CALG for vocals in general.

- Another interesting comparison is with the Audiovalve Solaris. The Solaris is a very well-composed and clean tube amp, and the 394 is a relatively punchy and not overly bright solid state amp. It's not warm in the way Pass Labs amps are, but it is in many ways less solid state-ish than the GS-X mk2 or the Headtrip, just like the Solaris is less tube-ish than the WA5 or ZDS.

- IMO it pairs best with the TH900, Utopia and Abyss 1266 phi (which is what I use it with). The HD800 is also a truly excellent pairing (Mr. Mass uses one with his 394). I like it a little less with the LCD4, and I don't think it has enough power on tap to get the K1000's to their best possible level, although that has more to do with the crazy amount of power they need.

Anyways, before this turns into a full-blown review, please PM me for questions. Local pickup in Boston preferred. Shoot me an offer if you're interested. No trades other than a Chord Dave or Hugo TT2.

Edit: Pictures added. S/N build date is 05/2016.
Last edited:

Users who are viewing this thread