I'm just about as new to this forum as I am to this machine, an otari MX-5050 BQII 1/4" 4-track, and to analog reel-to-reels in general. My only other experience with this stuff is on an MTR-90 2" 24-track that required minimal calibration to sound amazing.
I picked this guy up a few days ago for only $250 (!!!) complete with the roll-around cart, a bunch of take-up reels, 4 new reels of quantegy GP9, an (albeit ancient and flaky... more or less useless) MRL tape, a demagnitizer, and the original manual. The guy who had it before me barely used it and only owned it for a few months, having bought it on eBay from a quiet connecticut studio. It looks practically new... all-in-all an amazing purchase.
So I started playing around with it, cleaned the heads and stuff with isopropyl, and noticed that it was pretty horribly calibrated... I could slam the inputs but the signal coming off the tape was wimpy. I whipped out the manual and cracked open the case and began twiddling; it wasn't long until I had the first three channels at their proper levels, but channel four seemed pretty flaky. I calibrated the input section and all seemed well, but both the sel-rep and repro heads pull very little signal off tape. I swapped channel strip 4 with 1, and the problems stay on track 4.
So I have some questions... where should I be looking for the problem? It would seem to be in the heads, but I would doubt that both the rec and play heads are equally mis-aligned. If I monitor the sel-rep head while recording (using the onboard test oscillator at 1k), the level is exactly what the input level reads, so the signal is making its way out to the rec head at the proper level. From there... I don't really know what to check... I'm thinking that maybe I should flip the tape over and see if what was not working on channel 4 comes out channel 1 properly...
I'm a touch nervous about playing with the alignment of the heads too much as I don't have the proper test equipment (though it seems that the HP voltmeters and oscillators and stuff the Otari manual recommends are quite cheap on eBay). I just don't know if I should bother getting this stuff, or whether it's necessary in my case.
So if anyone with some analog experience could shed a little light for me, I'd be extremely grateful... thanks in advance!