OK......here it is in a nutshell. I will give more details later when I have time.
The Redgum RGi-120 is working the best for me. It has the most taut, detailed and weighty, fierce bass.......by a long shot. I'm not simply talking quanity here. I'm saying quality. Bass of every other amp was soft, round and indistinct by comparison.......even the Butler bridged monos at 800 wpc! I know....hard for me to believe too!
I tried the two Butler 2250 stereo amps three different ways:
* one stereo amp (250 wpc)
* bridged mono (800 wpc)
* vertical biamp (250 watts to each driver)
The best was bridged mono. It beat the vertical biamp. I can't really say how the vertical biamp compared to the stereo. Once I realized bridged mono was the best, I didn't listen much to other configurations. The Butler always sounded relaxed, smooth and composed on the Sunnys. It never got aggressive or bright sounding.....much to my surprise. So much for preconceived notions.
My big surprise with it was the lack of bass punch and slam. Sure it could play loud effortlessly, but the bass was billowy and soft, despite the humongous power on tap. Bass attack and leading edges were simply MIA.
In my research on the Redgum I came across a comment on some audio board where the poster said that the Redgum bass is boosted by 3, maybe 6 db. I have no idea how he knows that, or if it is even true. If it is true, I really don't care cause the Redgum bass just sounds really good to me. To my ears it sounds completely natural and in balance with the rest of the range. It does not stick out or sound hyped or overblown at all. It just sounds "right". A buddy of mine (with a killer system) thought the same -- he loved the Redgum bass presentation.
Redgum is clean and fast everywhere. It has the most coherent, incisive, open and "interesting" presentation of all. Music has a natural rhythmic flow with it. Every time I switched over to another amp I found myself wanting to go back to it in very short order. That just about says it all. Seems more powerful than it's specs.
None of the three Class A amps (Bedini, Rawson Aleph clone monos, Monarchy monos) are working right in my system. All are very similar in their presentation: soft and dark, and lacking in incisiveness and rhythmic drive and slam. They all have great reviews so it's gotta be a synergy thing with my speakers. They are all similar in output power ( around 80 wpc) and since a 38 wpc tube amp drove my speakers with much greater gusto, detail and openness, it should not be a power shortage thing. I'm guessing that for whatever reason, my speakers just don't like the Class A circuit.
It's too bad cause I can hear that they are real nice sounding amps --smooth, rich and musical. Just lacking in drive and a bit shut-in sounding in my setup. Would love to hear them on a more simpatico speaker, for I am confident they would be VG on the right one. Just don't have the available funds to satisfy that curiousity right now.
The McCormack is my 2nd favorite, but the Redgum beats it quite handily in the bass dept, and is also more open, fast and incisive sounding. The music gets exciting with the Redgum in place, especially bass heavy stuff. It has a rhythmic drive, attack, weight and slam not yet matched by any other amp I've tried. It also has a crystal clear sound over the entire freq range that manages to avoid peakiness, shrillness and edge. Vocals and lyrics come thru more clearly and intimately with the Redgum.
None of the SS amps ever got aggressive, or hard, or bright sounding -- a pleasant surprise for me. The Sunnys are not a typical horn. They exhibit none of the typical honk or shout or peakiness of said designs. They are quite relaxed sounding. I can't say for sure but my guess is this is why the Class A amps are not particulory suited to them...cause they lean in the same direction. I would not call the Sunny horn loaded mid / tweet "ruthlessly revealing". To my ears it leans to the smooth, suave and refined side of things, and actually needs a little verve and gusto to wake them up.
I know some are probably surprised at these results. I know I am. The Redgum is so small and unassuming looking, and doesn't have the rep or audiophile approval credentials of these others. That is mainly the result of the lack of a marketing presence in this country, certainly not a reflection on performance! Do not sell it short. It is a very good
amp. I have been rolling these amps in and out now for several weeks, so I am quite confident in what I am hearing. Additionally, a few audio buds that have visited and compared them concur with these findings. So I'm not crazy, dammit!
I'm not saying that any one is absolutely better than another. Just commenting on what works best in my system and for my ears. If you have a different system, and a different set of ears, it is quite possible you will choose differently.
Remember, this is just my choice from the SS I have on hand. I am still missing my tubes. No SS I have heard in here gives the lovely liquidity and 3D space and palpability and presence like they do. In my experience SS does not convey that sense of beauty and wonder (when called for in the music) that tubes do, and SS cannot stir my soul or connect me emotionally to the musical message as well as tubes. I loved my PrimaLuna integrated from the mids on up. Just didn't have the low end control and slam I need. Need to combine that with the Redgum bass and I am set. Passive bi-amp, anyone?
More later....maybe. Feel free to ask questions. Anyone who knows me knows I will give my honest assessment of things. No sales pitch here. No need for it. I know they are all great amps, and in the right system will make someone very
Oh, forgot to mention. D/T my fondness for tubes, and to keep comparisons equal, I ran my Minimax linestage into the Redgum's line level inputs. (Remember, it's an integrated). I can't access the amp section directly, but it's line section is passive so I simply fully opened up its volume pots. Redgum still came out on top, despite this slight handicap.
PS: the Butlers and the McCormack are on loan, so they are not for sale.
Thanks Chris and Bob!
OK...not so much of a nutshell!
Sorry for the long-windedness.