Hi All, I noticed that my home recorded tapes, recorded from LP using a Kenwood KX7030 deck on older TDK SA90 tapes sound dull on my walkman. But when I tape over the hole for tape type detection so that it plays with type I settings, the sound is noticeably better. The cassette deck I used for recording has autobias settings, and not really a way to manually change it. What can I do to make sure that the recordings sound properly with the type II settings. Or should I just tape over all the holes and live with it? I'm wondering if my recordigs can sound better with a different setting or way of recording. Job
Assuming the Kenwood KX7030 deck has the tape path alignment right, your WM-EX512 likely has a tape path alignment problem. However the KX7030 being a dual-capstan deck wouldn't necessarily assume has good alignment because such decks are sensitive to belt used, pinch rollers condition and the supply roller height adjustment. Covering the holes of the cassettes with tape is not a solution, as 120us EQ also adds more noise and doesn't adress the root cause. You won't have a flat frequency response by doing this, just make it sound better by boosting the highs, while also boosting noise floor at the same time. First thing I would do is test those recorded cassette in a different player if you have that possibility. This way you can confirm if the deck's alignment is right or not. You can also use a pre-recorded tape for this test. If the walkman is confirmed to be the issue, things to check are the pinch rollers and head position (to not look angled, the plate on which is mounted can get bent).
Thanks for the rundown! I have replaced the belts and the pinch rollers in the walkman, and pre-recorded tapes sound quite nice on the walkman, so according to your rundown it seems that the KX7030 is to blame, which I assumed. I only replaced the belts there. Should I replace the pinch rollers preemptively? I have no way of checking the azimuth other than by ear, and the deck sounds fine. I have no other player that I can use to test at the moment. Should I get a test tapes to check it? I see some for 60 eu which is quite a lot, are there cheaper alternatives for test tapes for azimuth? What is the supply roller height alignment? How can I check this? The pinch rollers look fine to me on the deck, and wow/flutter seems to agree, it's around 0.08% RMS. Speed is perfect too. Wow and flutter on the walkman are 0.25% RMS, this is quite high, perhaps another clue?
Wouldn't jump on replacing the rollers peemptively, as not all new rollers are same quality as the original ones. Clean them well though. Ideally azimuth isn't the first thing to check/adjust either, as the height of the supply roller does influence the tape path on a dual capstan deck (that's why it is adjustable). What you can do is check the alignment with supply roller engaged and disengaged (manually pull it off the tape). If it's adjusted correctly you shouldn't see any difference in the waveforms/phase. As far as test tapes go, you can get one from HansPeter Roth, see the attached image. You need tape at the position 3. They're nowhere near 60euros (for just 1 tape) and are very good tapes. W&F is ok at 0.08% WRMS, but that's around double of what it should be (0.045% WRMS). As with tape path you can check the W&F with supply roller lifted off from the tape. Ideally lifting off the roller shouldn't change the W&F figure. It's what we want to see in this scenario, case in which the higher W&F is caused by something else and can be ingored at the moment (as it's not related to tape path). On the walkman itself however that 0.25% WRMS is fine for this unit. W&F on these will depend a lot on motor and capstan bearing wear but also on the belt itself, but at this value it's not an issue.
Hi Valentin, Thank you again for the great advice! I will get the Azimuth test tape. Is this the one I need to check the waveform with the supply roller? or can I use the 3000HZ test tape I got from fix your audio for this? If the w/f is better with the supply roller disengaged, I think this is a case for a misaligned supply roller? Thank you so much for your time and effort! Job
When I disengage the supply roller when measuring w/f the speed is a bit faster, about 30 hz, and w/f remains the same, still around 0.08% RMS I have also looked at the waveform of the 3 khz signal with software with the supply roller on and with the supply roller disengaged. Please see the Screenshots, i don't know if this means something but there is a change. i have ordered a 10 kHz azimuth cassette. This is with thre roller disengaged And below with the roller engaged Job
If the W&F doesn't change it's good. Fact speed changes is likely from the extra drag, but would ignore it for the time being. As far as test goes, you can do a rough measurement with the 3kHz tape also, but this has 2 problems: - the frequency is a bit too low for this measurement; - it's not recorded as a full track (with mono head), so any phase differences that existed on the original recorder will exist on such tape;
