I have heard Soulution 5 series, Boulder (2060 generation so much older), Gryphon (owned Mephisto) and Robert Koda (own K160s today). All of these were either in our system or in a system very very similar at the store which I have known for nearly 20 years (same speakers as at home, same cables, different source (DCS Vivaldi vs Zanden 4-box at home). *BTW, I have also heard Constellation (excellent) and Ypsilon SET Reference Monos...but since you did not ask, will not take up any more air time on those.)
My observations:
- Soulution was very evenly balanced, powerful and you knew it had detail. It was subtle, but I think the 'messaging' in the signal was that the musical detail was just a touch (I mean a touch) highlighted so you knew it was there. By touch I mean, when you heard it, the detail retrieval occurred to you. You noticed it. In the end, I really respected it just did not feel passionately about it.
- Boulder was clean, effortlessly powerful and ultra q-u-i-e-t. I admired the fact that it came across as utterly unflappable in the sound room...but it even appeared to be the kind of amp you could drop down the stairs (so heavy!) and it would still work perfectly. Built like a tank and well built. And that kind of solidity, confidence also came thru in its presentation...again utterly unflappable by any signal, no matter how powerful, how percussive, deep, high, loud...or sometimes equally...insanely soft (almost missable without a super low noise floor). You felt someone was giving you the unvarnished truth...I will come back to this point later...and so it would seem that is entirely Boulder's goal.
- Gryphon. I have owned the original Antileon, Colosseum and then the Mephisto. So know them well...10 consecutive years, and between nearly getting the Boulder and then 3 Gryphons...super-powerful, pure Class A has been a theme for me. Right or wrong. The Gryphon's emphasis is on creating such a remarkable lifelike presence in music that it breathes a powerful sense of life into performances. Part of that comes from what I have now come to believe is a shade of extra power in the mid-bass (not much mind you, but 'just enough') that when you play recordings through them...piano, vocals, guitars have a power to them which is unmistakable, addictive and something you can easily sit back and soak in forever. It is super addictive, satisfying and whether you are at volume 1 or 100...you never lack for body in your music. I really really got a thrill out of that from Gryphon. Additionally, as time went on, the much much earlier (original Antileon) sense of darkness fell away, and generally speaking, while Gryphon's propsulsive bass tends to add weight to sound (and arguably a darker tone)...it really has a very very filigreed set of highs that are also very extended.
- Robert Koda. Now this is a tough one. First, I come back to the 'unvarnished truth' of Boulder. It was what I think of when I hear it, and that includes the term unvarnished. Some have found that some fundamentals or harmonics in the notes are ever so slightly stripped. On the one hand, I think I do see that in the older 2060...on the other hand, I can see that your upstream equipment could probably very easily counterbalance that. So it is a signature but not an insurmountable one.
Now we come to Robert Koda. This is a designer whose background is Kondo (ultra extreme, ultra custom, ultra music-as-a-pure-form-of-art) but who after 20 years has evolved to entirely solid state (again, pure Class A) and entirely his own designs. But he applies his intensity and extreme Kondo-homage purity ethic to his own solid state designs so that rather than deliver unvarnished...he literally seems to be design the purest and simplest circuit with the lowest noise floor (and does things like pure solid copper chassis tp block EMI, RFI, etc), design an insane 238-part hand soldered attenuator, where only 2 parts actually touch the circuit at any given volume or something crazy like that)...and his K15EX emerges as something that truly is the closest to pure music I have ever encountered.
Meanwhile, he takes this same ethos recently to develop the K160s...much, much tougher to figure out for me, coming from a Gryphon background. I drop them in...and they are so pure, so low-noise-floor and so effortless, they make the Gryphon feel like it has mechanical things going to reproduce sound. BUT...here is the BUT...it takes me a YEAR to finally get the bass right. Why? Because the entire system had been meticulously set up around the Gryphon whose propulsively powerful bass is renowned.
Whether the Robert Koda is absolutely dead even across the entire spectrum, I cannot say. All I can say is that after reworking the entire system, piece by piece particularly including repositioning the speakers by centimeters and Absolute Sounds adjusting the internals...the bass is extraordinary...breathtaking articulate and nuanced in a way the Mephisto was not in our system (despite being supremely articulate). And shockingly, much more extended...much deeper and more resolved at that depth. Even the famous midbass of the Gryphon is bested by now the Robert Koda...but it took a lot of minute adjustments across the entire system that had been living with Gryphon for 10 years consecutively. And by bested, I do not mean that the Robert Koda now has a protruding midbass, but rather that the finetuning of the system now provides a depth and power in the midbass that when amplified by the Robert Koda has pure power while at the same time having extraordinary nuance. And this gives a richness of detail and life to the midbass...without making it fulsome or weighty to do so. It just feels right. Finally, the Robert Koda bass is firmly best in sheer all-out power and now shows me that its bass always had the ability to match the absolute organic purity of its midrange and treble.
Relative to the Gryphons, the Robert Kodas are NOT drop-ins. The K15EX probably is for most systems to be fair. But you have to be ready to ensure your system is set up to produce exactly the sound you want BEFORE it gets to the Koda K160 monos...and then as soon as it does reach them, they will produce effortless, powerful, organic, nuanced music. But if there is something up in the chain just off (particularly in the bass), there is no extra fat in the K160 to smooth that over. It just wont play it until your system delivers it. it took me a year to get it right, and it has been another year of finetuning the upstream. However, this extra year of finetuning has resulted in extraordinary improvements where I realize that without the Robert Kodas, I would probably not have been able to achieve this because the earlier pre-Robert Koda amplification would not have been up to it. It takes time and effort...but the Robert Kodas make that so eminently worthwhile in a way that no other piece of equipment ever has for me with perhaps its equal being the Zanden 4-box which after 15 years remains in the system to this day. A note of advice if you will.
Hope that helps. One man's experience.
Thank you!
