@Jafox (and others): That might be (and probably is) a flawed electronics somewhere in my system; however, I don’t think that the CA-7A, a flagship preamp from Nakamichi is intrinsically flawed. This might not be just a bad preamp design, period. This particular CA-7A might need more tune-up or replacement of some parts. Alternatively, some other component(s) of my system should be replaced (e.g., Luxman with dedicated power amp). All specific suggestions and comments on this subject are welcomed.
What is NOT WELCOMED though are comments on what priorities I should or should not have and what type of gear I should or should not use in my system, no matter how obsolete you think they are. You set priorities for your own system and other people set priorities for theirs.
@Almarg: Thanks for the suggestion to use high-capacitance cables. I have A DMM with capacitance test function and will test cables on hand. However, I would not like to sacrifice the bass output for things like soundstage or dynamics so cheap $20 high-capacitance cables might not be the best thing to use…
To all: The preamp got a dedicated power cord five days ago and it results in a DRAMATIC improvement of sound. Missing bass and lower midrange appeared; in fact, in some records I hear too much or “muggy” lower midrange. The cord is nothing special, Audio Thrills with the retail (new) around $70 or so. I didn’t believe in power cords importance for low power consumption gear such as preamps before.
