To Philip Beaudette,

I enjoyed your review [of the Simaudio Moon Evolution 600i integrated amplifier]. Having owned three generations of Simaudio integrated amps (I am looking to replace my venerable i-5 integrated with my last amp; yeah, audiophile promises, just like drunkard promises!) and hearing their higher-end stuff at stores and shows, I am familiar with the overall Sim sound and design philosophy. One thing I did not catch in your review concerns the so-called liquidity/lack-of-hardness/tube-like sound, etc., or whatever other adjectives are often used to describe this aspect of audio reproduction. Do you think that the 600i conveys some or a lot of that sonic trait? In my quest for that last amp, I’ve recently listened to an Ayre preamp/power-amp combo (Vx5e and Kx5e) and I am struck by how your listening impressions of the 600i -- notably the silence, transparency, ease of reproduction, etc. -- match what I heard from the Ayres with ProAc D28 speakers (I own the D38s, so I am salivating at the potential), which also provided the neutrality with that smooth sound I am asking about.


I don't know how Simaudio’s 600i would compare with the Ayre Vx5e and Kx5e combination that you heard, since I have no experience with Ayre. However, I think the term “liquid” is an apt description for the 600i. It does sound very smooth, but I wouldn't go as far as saying it’s tube-like. The 600i’s noise floor is just too low and the amp is so firm in the bass that it’s a solid-state amp, through and through. That doesn't mean it sounds hard, though. The 600i reveals the character of the recording and won’t mask any harshness that is already inherent in the music.

It sounds like you are pretty familiar with the Simaudio sound. I reviewed a couple of less-expensive Simaudio products before I ever wrote about the 600i, and I will say that this integrated does have Simaudio’s house sound. It just takes things to the next level. If you already like what your i-5 does with your ProAcs, you can expect the 600i to take performance up a notch while still retaining those things that I imagine you already love about the sound of the i-5. But if you're looking for a different sonic flavor, it might be worthwhile to look at another brand (such as the Ayre), since I think you'll hear more of a difference listening to another company’s products rather than another product from the same company. The best thing, of course, would be to find a dealer who will let you borrow the 600i for a weekend to try out with your speakers. For $8000, they should expect you to want a thorough audition. . . . Philip Beaudette