After a long wait I finally got my MASS 100 a couple of days ago, so I thought I'd share some experiences after two test drive sessions. First the obligatory pics:
The rig I tested it with: Laney GH50L, T.C. G-Sharp, Framus 2x12 loaded with Celestions and my trusty HSS strat.
The front panel:
The rear panel:
I didn't quite know what to expect from MASS so I was really curious to try it out. What I found out was that it does seriously improve the tone at reasonable volumes, but it still isn't the ultimate key to getting godly tones at bedroom levels.
For example, when I'm playing through the GH50L without the attenuator, the master volume is around 2 (this is with high gain, with clean tones you can go beyond that), and it's still quite loud. Now, with MASS I can run the master volume around 5 and still get the same overall volume levels. When playing at strictly bedroom volume levels (with the Laney that would mean master volume at around 1), the tone is still better, but whether the improvement is worth $200 is subjective. A POD setup will probably sound better, but on the other hand a formidable full stack in the corner sure as hell looks better
What difference does it make then that the master volume can be turned from 2 to 5? It seems to depend a lot on what you're playing. In every case it took away some fizziness that occurs when you run the GH50L at really low volumes. For metal rhythm it didn't do much beyond that. It was a nice improvement, but what impressed me a lot more were the high-gain lead tones. The MASS made them a lot thicker and fuller, a definite improvement there.
What MASS did best, in my opinion, were the low to medium-gain rock tones. If you dime the master volume and add just a little bit of gain, the overdriven tone with a strat neck pickup is so damn delicious it's unreal. Crunchy, ballsy, and chords still ring clearly without any mud. If you like playing this type of stuff in addition to metal, I can recommend the MASS in a heartbeat.
I found the +3/+6db treble boost option a bit redundant. It was probably implemented to compensate for one of the main drawbacks of attenuators: having the sound get muffled when using heavy attenuation. In this case MASS simply took away some of the ice spikey tone of my GH50L+V30 setup, which was nice. Some other amp+cab setups will benefit from the treble boosts, no doubt. In any case it would be a good thing if your amp had good EQ options to compensate for the MASS characteristics you don't end up liking. With MASS my amp's EQ curve is completely different than without.
I also couldn't resist trying to dime the amp with gain maxed - it didn't work well at least with this setup. There was no real improvement in tone, and the feedback was really, really bad. I'll try this again with another axe and better humbuckers, but I don't think maxing the master volume gives any benefit anyway apart from when you want to mildly overdrive those power tubes.
Oh, and a final public service announcement: you don't fuck with the bypass switch, the bypass switch fucks with you! I had the master volume beyond halfway and forgot to dial it down before flipping the bypass switch... almost shat my pants standing right next to the cabinet
I hope I can post some clips sometime demonstrating the effect MASS has. In some cases you do not have to be a gearhead at all to hear the improvement, in some other cases it's very subtle.
Thanks for a good review
I think no attenuator will really work for good metal rhythm at low volumes, as you really do need the speakers to be shifting some serious air to get a good sound. ie. it has to be loud. However, I've found my Mass Lite to be a good solution that lets me use 100W tube heads without seriously falling out with the neighbours. It means I can use my live rig at home for nice tube goodness without having to spring for a seperate rig.
Having said that, for anyone who just plays at home and doesn't plan on ever playing out, I'd recommend a lower wattage tube amp or a Pod/low wattage valve power amp combo over a big wattage head & cab with an attenuator.