Okay, OzarkTom sent me his amp and I have spent a little time with it.
Usually when an amp comes in for me to listen to there is always some setback or some negative quality that stands out. I usually notice it right away and it is hard for me to get past. I am just used to some really nice amps and it is hard for me to go back to average or typical. However, this one was different. Hmmmm... okay... wait a minute.... really? Hmmmm...
I had a pair of Serenity Acoustics Super-7's burning in so it was no problem to drop this amp in. I had no idea what this amp really was or even what the power rating was. I just dropped it in and turned it on. These speakers have 97db sensitivity and the amp only drives them from 200Hz and up. The lower ranges of these speakers have their own servo amps.
I hooked the amp up using the supplied small battery.
Funny thing is not a whole lot changed for me. I took me a while to let it soak in that this was a different amp. Critical listening noted differences from the tube amps that I am used to. But the differences weren't night and day or buzz kill differences. Nothing really great stood out to me, but nothing was really wrong either. The amps were pretty smooth, real balanced, had good detail levels, and a good vocal range. Even the dynamics were real good. I had no idea it was only an 8 or 10 watt amp.
A little back and forth with my little Dodd Audio, battery powered, 30 watt mono blocks, with some selective music revealed what one would expect. The little MG3 lacks some of the lushness in the mid-range. It was not quite as musically involving as my tube amps either, but it was no blow away. My tube amps also had better imaging and sound stage size, but not by a lot.
This is a great sounding little amp. My only real gripe was a little bit of buzz or hum. It was clearly louder than my tube amps (they are very quiet) and could be heard from the listening position. On a speaker with 90db sensitivity or less it might not be heard. But on a speaker with 97db sensitivity the humming needs attention. If that humming noise floor were dropped out then I'd really like it.
I also couldn't help but wonder how much better it would sound if I put it on my big 100 amp hour battery? Being battery powered is a great thing. AC power and noisy AC lines are pretty rough on these digital amps. The last set of digital mono blocks that came through here were really finicky about power cables and power conditioning. They needed a good $1,500 worth of conditioners and cables ahead of them for them to reach a reasonable sound. This little MG3 amp was plugged into about a $16 battery.
I also noted it sound better with the volume knob pulled back a little from wide open. Usually these cheap little pots sound best all the way up. This usually puts less resistance in the path, and sounds better. Not so with this one. And the hum was a little less too. It might sound better if this pot were removed too. I controlled the volume with my Dodd Audio battery powered pre-amp.
My whole system is off the grid except for the amps powering the servo subs. So this amp fit right in.
Two thumbs up for this little amp.
