I guess we all just view things a little differently. I would certainly consider the Avalon 2022 to be clean in that it has a natural sound. In my suggestions I was suggesting more of the "transparent" or "straight wire" sound. The Avalon 2022 is a pretty sound but you know you are using it (which is a good thing right?
). I certainly would not consider any Focusrite to be this way, or the ATC-2 as well. The Focusrite BLUE series make wonderful preamps, the RED series as well, but I have never really liked them as much as the BLUE (ISA) stuff. Personally I will never buy a Platinum series one though. They aren't bad for the money, but to me that have that "sterile" sound, and not in a transparent way like the Grace does. The ATC-2 in my opinion is one of the best bang for the buck channel strips. Pretty nice sound, sweet EQ, decent compressor. Basically a solid performer at a great price to feature to sound quality ratio.
However, when you listen to something like a Martech, Millenia, or a Buzz audio preamp, you will hear what I mean about the whole "transparent" thing. I was very worried when I bought my D&R console because I was commiting to 104 channels of very clean and transparent preamps. At the time I was leaning towards vintage Trident, maybe an MCI, and even considering an old SSL. However, my console was coming from someone I know and trust, it was only 7 years old (which is pretty new for a used large format analog console), had 3 brand new power supplies, and been upgraded with real P&G faders. It also came with one of the best tech support systems of any large format console out there (I have become good friends with the only US D&R rep and tech guy in the US). I do mostly rock and in general I love the whole "colored" sound. I discovered very quickly that the degree of transparency that the D&R puts out is almost a "color" of its own.
I guess what it comes down to is that "clean" or "transparent" is some sort of a personal observation. If you have using ART preamps, or Mackie's, or Soundcraft's, Behringers etc.... than yes a Focusrite or
an ATC-2 may seem very "clean" and "transparent to you. Then you get something like
an Avalon AD 2022, and all of a sudden you realize a new degree of this. Then you get a Martech, Millenia, Buzz, D&R etc... and the way you view your other equipment changes yet again. This isn't a bad thing. In fact its a good thing. As an engineer going through these changes it expands your sonic palette, and teaches about whole different sounds that prior to that you may have found unobtainable or impossible to achieve. You don't even have to get rid of the other stuff either. Thats the great thing. It teaches you how and when to best use your other gear to maximize your capabilities. I find that my D&R preamps in my console are actually very similar to the Avalon 2022. The biggest difference is that they tend to "disappear" a little. The Avalon is nicer in the sense that I feel like it adds a "smoothness" to a track. An almost gently and sweetly processed sound. The 737 retains some of those same characteristics (if you are driving it too hard) but adds an enhanced mid low and like 8k type feel that doesn't feel as natural to me, but in many ways feels a little "larger". This can be both good and bad depending on the source, the mic, the engineer, and the desired sound.
I hope this post quantifies a bit about where my OPINIONS are coming from. I don't want anyone to think I am talking badly about the other gear listed in this post. I am just trying to describe how I came to my opinions