GMA Callisto

Well I've been doing some reading up on these speakers (mostly old threads). The 6moons review was the most recent and that peaked my interest even more.

On to my question what do current owners of GMA speakers use for a source and amplification. I'll be honest I've read only good things about the Berning ZH270 so that amp is at the top of my budget.

Early next year I'll be demoing a BC Galatea3.1 with my current setup.


I like the direction you are heading with the GMA Callistos. Amplification for me over the past 16 months has been a pair of AES (Cary) Sixpac monoblocks. They are 50 watts triode. I moved to tubes from a very nice Pass Labs x250 SS amp when I had my GMA Europas and I'm not looking back. Lots of air, lots of smooth across all frequencies. As always, call or write Roy at GMA, he'll talk your ear off regarding anything audio, I'm sure he'd have a thought or two. Good luck.

Thanks Mijknarf,

I remember seeing your system when Im did a search for GMA Callisto's under Virtual Systems.

I hope on my road I don't get distracted. I plan on giving Roy a call in the new future.

I use a levinson 331 with a bat vk5i pre. There was a thread a while back which Roy responded to in which he recommended some amps - edge for SS if i recall and manley for tubes. Check the older threads and see if its still there. If not, email gma or call em.
I know an Agon member that owns both the Sixpacks and a Berning amp, he may be a little more help than I. E-mail me if you wish. I have zero experience with the Berning, it certainly has a good following here, I'm sure it's a worthy candidate as well. Regarding "getting distracted" it's always good to go for a home demo, or buy used and re-sell if not what you expected. There is a ton of equipment out there, the possibilities are endless. True peace of mind lies with home demos that you hear for yourself.
I use a Cary Rocket 88R and Cary SLP50A with oil cap upgrade. All tubes have been replaced to nos of my liking and I have not turned back. The Callisto speakers still amaze me after a full year. I listen almost every day now and buy more and more music. Best audio purchase I have made in 30 years. Green Mountain Audio is a special place and I still communicate with Janet and Roy. Any questions, feel free to email me. I am a huge fan.

I have not heard the Berning ZH270, but I do know the Callisto's will show the quality of the equipment connected to them. Enjoy!
Well after reading numerous posts on AA(maybe a bad thing) I do now have some questions. What now has me worrried is how they sound if I'm not in the sweet spot, which it seems for these speakers is small.

Short of demoing these in my own inviroment can anyhere comment on how the sound differs from say sitting down to standing up all at the listening position.

2. How expansive is the soundstage
3. How does it differ say walking around.

Those are my biggest fears as my quests would never experience what I do.


I don't know what was on AA, but the sound stage is huge and fills my whole house. I can sit to the side and still enjoy these speakers. The sweet spot is everywhere, not just one location like planer speakers, ect. Yes, there is one perfect spot, but it is not very noticable and took some work to actually locate it. The set up has a tilt to tip the speaker forward or back slightly and the difference is so small, it takes time to find it. I sit, lay down, sit somewhere else, or walk around and I always enjoy the Callisto. You really need to hear these. I enjoy the Callisto so much, I upgraded my equipment also. There is no set sweet spot that if you leave that spot you will not enjoy them. That is the beauty of the dual bottom ports. Music is everywhere and not really directional IMO. I wonder if the posts were meant to damage GMA since the posts could not be more wrong.
Give Roy a call at GMA and he will give you the technical on the Callisto. Also, send me an email and I can send you pdf. files of documents on the Callisto that Janet Lynn, the CEO of GMA sent me recently. Lots of information in these.

Thank you for taking the time to answer my questions and to offer up information.