Do YOU like how your system sounds? If you think the bass is flabby, then you could add a powered sub, and remedy that. If you think it needs to be more transparent, then upgrade the tubes, in both the preamp, and the DAC. You have a system, capable of producing fine sound, with proper setup. So if it sounds fine to YOU, then it is fine.
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this is a stereo I have put together from used pieces, as I do not wish to jerk around I am looking for advice on what my next upgrade should be, I will probably buy used but I am not totally oppsed to buying new, my system------> Sony 7700 (as transport), Illuminations D60, CAL Alpha, Kimber select 1010, Audio Research LS-9, Kimber Hero, Golden Tube SE40, Kimber BiFocal L, Castle Severn 2-----> any recommendations helpful, if you have found that some of these components do not work well togehter let me know as I do not have the experience to know better, I just figured this system would sound better for the money than buying a system for retail.