Hello,
I have this Cary SLP90 Clone tube preamp. I did eventually get it to sound very good after some minor work: replacement of the 3.3uf 400v caps with mundorf aluminum oil caps which are great value priced, and premium 12au7 tubes.
The online reviews on this preamp as stock are over the top exaggerated in my opinion when compared to my custom tube preamp but I never expected it to be that good anyway. Stock the soundstage is very big, and the mid-range is a touch opaque. Replacement with the I expensive mundorf Alu. Oil resolved the opaque issue. Also it took a long time to burn in and sounded harsh prior to getting lots of hours with the Mundorf caps. Definitely highly recommended as a high value proposition tube Preamp! Go for it. The caps are not expensive and it's easy enough to swap out yourself if you can solder. A few of the small white Vishay caps were cold soldered so I just added more solder all good. Sounds very good in my secondary system. Excellent high value purchase I do not regret.