I have the Sony Es 999 CDP. I'm interested in modding the unit, but I need some more confidence in my decision. Will the mod make a significant change to redbook sound or is it a subtle change that requires "golden" ears to appreciate? I have been told that I would need to spend at least $3500 on a new CDP to approach what Dan can do to the Sony. I'm not unhappy with my current sound although I feel there is some "edginess" on redbook. The stock 999 LF extension seems to be adequate and fairly tight. I find the 999 to be resolving in its presentation and I wouldn't want to lose the resolution in favor of a tube-like quallity that might lose some definition. If you have some insights, I would certainly love to heat them. I have some input over on audio asylum, but I thought there might be some valuable opinions over here. Thanks in advance for your insights.