I recently fully restored an Aiwa J9. Had one question when fine tuning it. As most other Aiwa walkmans, Dolby level is supposed to be 100mV +/-5mV on ANSI 200nWb/m test tape. The test point is at the Dolby IC output, right before entering EQ and power amp. Given 40 year old components and some head wear, this machine’s L/R channels are not exactly equal. I was wondering about two adjustment options: (1) L/R channels matching 100mV at the test points. At headphone output, its Left channel would be slightly higher than Right at all volume levels. EQ/Amp gains are not exactly the same maybe due to deteriorated caps. (2) L/R channels matching at the headphone output. At Dolby test points I would get 96mV on the Left and 102mV on the Right, or 0.5dB lower on the Left channel from the pre-amp. Since there’s no separate output level adjustment points, I went with option (2) for overall balanced L/R channels, but still wondering if that’s the best practice?
