Adromada III or sumo nine

I have a polaris class a/b. probably more along the andromeda sound. Back in the late 80's I listened to both of them extensively and the polaris to me was had more natural clean harmonic structure such as in the overtones of a guitar. I kind of wanted a to hear a nine but never did. It is little forward in a nice way. Also compared it with rowland model 1 on theil speakers and a lot of similarities even though different because of mosfets and bipolars but the polaris was 90% of the rowland in that system to me. I know this is not about the polaris but it is nice to hear about Sumo's and know of potential upgrades. Thanks

Hi Brian,
Jason Stoddard is still around, he is a co owner of Schiit Audio. He was the head designer at Sumo when Jim sold out and did the conversion from the Nine to the Nine Plus. He would be available to answer any questions, plus full Schematics are available online. As much as I loved the Nine, My modded piece is sooo much better than the stock, I'd hate to discourage anyone from improving this amp. Mike Bettinger used to do parts upgrades on this amp himself, he may also be willing to do upgrades.
Tim

Hi Brian_eno

Glad you are enjoying the Sumo amp you acquired. What is Revision C on the Nine Plus you have? Does that mean you have a 3rd generation Sumo Nine Plus? I don't think I've ever read anywhere about different revisions for the Sumo amps.

Mike Bettinger does great work on Sumo and GAS amps. He send me pics of the work he did while he was re-building my Sumo Nine and I was amazed. Very nice work. I'm contemplating a reference re-build for my Sumo but I really don't like being without it. Even in this summer heat I enjoy the music it makes. I did eventually get used to the fan noise.

Just acquired a Sumo The Nine Plus (Revision C).
Wonderful sounding little gem highly recommended.
Sounds almost as good as the Levinson ML-2's I once had, delicate and detailed.
Do not try to service/upgrade it your self because it needs more skill the your average DIY'r.
Had perfect feedback from Mike Bettinger from GASaudio(http://www.gasaudio.net/index.html). Very decent guy superb communications. The Nine and Nine Plus are worth the investment of upgrading by GASaudio in my opinion.

My vote is for the Sumo 9. I acquired one at the end of last year and had Mike Bettinger of GASAudio.net restore it this summer. The Nine really does sound phenomenal. After letting it warm up properly the music it makes is wonderful. From cold start it sounds fine but with the full warm up time it sounds great. The only thing I don't like about it is the fan noise. The 9 runs hot and the fan helps keep things cool but I can't find an AC fan that can push out decent CFM that is quieter than 33dBs.

There is no comparison to the two. I have been a Sumo dealer back in the early 80's and sold the Original Andromeda as well as the Andromeda II and the Nine. The Andromeda was a Bonjourno piece, all bipolar outs, very tight and controlled, very fast, but lean and a bit dry for my taste. The Andromeda II was not a Jim Bonjourno piece, this is after Randy Patton bought the company, Jim would not use mosfets at that time. It was a bit better in the mid range as well as not as dry on top, but not near as controlled on bottom nor as fast in its overall presentation. The Nine is just a fabulous sounding amplifier. Other than power, it lunches both of these amplifiers in every aspect. A year or so ago, I picked up a Sumo Nine and had Ed Martin of the old Marcof Electronics do extensive mods. Litz hardwired in and outs, nearly tripled the filter capacitance, replaced the bridge rectifiers with newer higher voltage pieces, tons of better resistors and alot of electrolytic replaced with pure polypropylene caps. This improved every aspect of an already very nice amplifier. The bottom is more substantial, everything about the wonderful midrange and top end stayed in tact and it lost the slightest bit of grain that it had. This has turned out to be an outstanding amplifier for very little money on the mods.

maybe a bit late here, but i have owned the Sumo Nine. reviews i've read about the Andromeda have not been good, but the Sumo Nine is a well regarded, if quirky little amp that makes a nice sound. can be a bit tiring to listen to, but if you like detail then you will be in heaven. it'll double it's output into 4 ohms, so there's plenty of juice. i enjoyed mine for some years before upgrading. definitely recommended, but if you need it serviced...

Been a few years, but the Nine had better sound quality than the Adromeda. Doesn't have as much power of course, but it actually was pretty decent if your speakers aren't power hawgs.

It was a balanced output working like a bridged amp usually does if solid state. For instance 10 volts out going to ground in a normal amp would be +5 volts and -5 volts on the Nine outputs. This potentially is good along with it being non-switching class A for sound quality.

I even used mine with some Acoustats for awhile. Had to be a bit gentle with volume, but within its power envelope it sounded good even on the revealing electrostats. It probably isn't as smooth and grain free as modern designs, but generally was a musical amp.

I had a 9 a rep left with me for a while when I was thinking of carrying them, I remember that I thought it was a good amp at the time but it was so long ago I can't remember much else except I thought it was well built for price.