GMA Callisto VS. Merlin TSM

Hi, sorry for a delayed response.

The system I am driving merlin is described as follows from the front end;

CARTRIDGE : Ortofon SPU AE with tuned original brass stabilizer and spacer mounted on SME 3009 on Thorens TD-124, SME stock cable

PRE-PRE AMP : BB OPA27 base gain amplifier, 18 times voltage gain , 100 ohms and 600pF input loading

CABLE : low capacitance teflon silver cable

PHONO AMP : passive RC RIAA filters between 12AT7 cathode ground resistor load gain and cathode follower buffer amplifiers

LINE AMP : FET-bypolar solid state with cascode differential front end, full symmetric over positive and negative rail

POWER AMP : bypolar differential front end with J-FET base constant current source, MOS-FET (2SJ50/2SK135)rear end, full symmetric, full thermal conjuction of positive and negative rail active devices, 136000MF and 600W class transformer in the power supplier

SPEAKER CABLE : 12GA silver plated copper strands in teflon insulation single pole wire used in random spacing between the wires

ROOM : 166" X 94" X 280", medium level damping with carpet and furnitures

OTHER : zobel network, jumper cable and speaker positioning instruction from Merlin was carefully applied - worked really well!

REMARKS : It is extremely transparent/sensitive and very picky for recording. I am going to try different phono stages and cables to make it more forgiving for some situations I have to play lower-fi recordings.

Only the tube phono amp has no feedback. I use TEAC MTZ-3 alignment mirror disc for the turn table alignment. The power amplifier is 75 watt RMS per channel at less 1% distortion at 4 ohm resistive load and it has internal zobel networks.

This post might be too late for Minbean now but I thought that I'd post it anyway - I visited the Green Mountain Audio factory in CO & heard the Callistos mounted on Skylan 24" sand-filled stands. The source was a Sony CDR (forget the model #), the DAC+pre was a modified Birdland Odeon-Lite, the power amp was a $2500 stereo Edge & all cabling was Virtual Dynamics Master series.

I can tell you that the Callisto stands up to all the hype that I have read about that speaker! The sound thru this system (modest by many of us' means) was simply superb! The factory listening room was nothing to to write home about but it was treated in the critical areas (ASC tube trap between the speakers + along the 1st reflection points, absorbers behind the speaker) but still the sound was extremely dynamic, transparent, clear & most of all the music had soul to it. Such good sound in such modest settings - to me, it felt that the speaker had removed the speaker-room equation. Common sense prevailed in setting up the speaker (proper separation, correct height, not too close to the back+ side walls & 100 hrs of burn-in) & not much more.
We played a variety of music & the speaker's characteristics did not change, the image remained locked at ear-eye level.
One of the most fascinating things was how much bass that little 6.5" woofer put out! On several notes I could hear it resonate in my chest! Totally unprepared for that! There is a dual down-firing port that is partially responsible for this bass + of course, the speaker engineering. The bass was distinctly ported (vs. sealed) but I'm happy to report that there was no overhang (something I was very antsy about before I heard the speaker).
Even if it is for grins, Minbean, do listen to the Callistos. They just sound right all the way & with any music. A speaker for all seasons!

try a fine stranded copper like audience au24s.
you'll love them.
b

"Such good sound in such modest settings - to me, it felt that the speaker had removed the speaker-room equation"
It has been minimized via physics. One of the great things about GMA speakers is that they sound good with most any amplifier. I agree with Bombaywalla, at least LISTEN to the Callisto in your room. It will take a few days to get used to the time/phase coherence of the product (after all, you've spent a lifetime hearing non time/phase aligned speakers) but once you do, you'll likely never go back to high order speakers again. I never dreamed that the crossover was screwing up so much in speakers I had previously owned and listened to. Minbean you should read the design concepts pages on the GMA website. VERY informative even if your NOT buying GMA speakers, you'll learn plenty about design. Might help you in your future purchases. Good luck.