Tascam 246 problem!

  • Thread starter Thread starter famous beagle
  • Start date Start date
The Ghost of FM said:
So, if the seller is willing to have the unit professionally repaired, go for it and stop messing with it any further as you may have already thrown it further out of whack and beyond what a semi-experienced tech can restore. And I'm referring to the dbx calibration calibration trim pots.

Cheers! :)
Click to expand...

Am I right in thinking that the meters should read the same on playback as they did recording?
 
Hey wondering if you ever found a solution here after all these years! Or what you ended up doing with your 246? I recently picked one up that’s in pretty great shape but with almost the exact same problem that you described in here. On mine it’s tracks 1 and 3 that record weak signals, so the whole left side of the mix.
 
I think low record/playback response would be a calibration issue, but to me would seem normal for this age of analog gear. You'd need at minimum a calibration reference tape for a double-speed cassette deck. I can't remember if you can switch off dbx on the 246, but if you can, switch off the dbx for calibration. You also need to remove the bottom cover and have a service manual reference for which pots to adjust. The very first thing you do is play the calibration reference tape, and adjust the playback level for "0" on the meter. Now you know you're reading "0" at a reference level. Then, you have a tedious cycle of recording to "0", rewinding and seeing how close to "0" it plays back, then adjusting the Record-level pots to bring up the signal. Your goal is to have a standard reference for "0" (Vu) playback, and adjust the record amps to that. It involves a lot of recording short segments of a test tone, rewinding, looking at your response, adjusting, and repeating until you get Record and Play to match exactly or as closely as possible. If you don't start with a calibration reference tape, you're really shooting in the dark. Without a legit calibration reference tape to start the process, you may somehow get the meters to hit "0" and still be wildly out of wack. Home calibration is a tech's thing or DIY'er's thing, but either way you should have some technical expertise and proceed methodically. I'm sorry if some of that is redundant.
 
Thanks for the long response! Something interesting that I’ve only just realized is that the problem is not consistent between tapes. I have a (used) Type I tape that records every track with almost no loss in dBs and a few NOS Type I and Type II tapes that all record poorly on one or two tracks, but not always the same tracks. e.g. could be 1 & 3 or 3 & 4 or 1 & 2, etc.
I wasn’t aware of this inconsistency because I’d been working with the same cassette for a couple weeks. The problem doesn’t seem to be the tapes because if I have weak recording on 1 & 3, I can flip the tape over and record on tracks 2 & 4 and then flip the tape back over and those recordings will have good signal playing back backwards on 1 & 3. But if I flip the tape over and record on 1 & 3 the signal will be weak on 2 & 4 when I flip it back over. So the problem is happening in the machine, not on the tape.

Hope I explained that in a way that makes sense, does it still sound like a calibration issue? It’s hard for me to understand why the recorder would behave so differently with different tapes. I’m going to do some more testing to see if there is at least some behavioral consistency between tape brands or anything. So far I’ve been trying to use something different with each test.

Another thing probably worth mentioning is that I haven’t ever demagnetized the heads, but I’ve got a demagnetizer coming in the mail next week.
 
You must log in or register to reply here.
Back
Top