Teac A-3340 Head adjustment / alignment

[AnnieJohnson]

Hi All,
I am trying to adjust Record and Playback heads on my Teac A-3340 but do not have access to any test tapes.
I do have the following equipment:
1. Audio frequency oscillator
2. Oscilloscope
3. An AKAI X5000 (which has its heads in original and perfect condition)

I wonder if someone who has more experience can read and confirm if I am using the correct approach.

To adjust Playback head:
1. Record a test tape (using 15 KHz signal) on AKAI which is 2 channels only.
2. Reverse the tape (as if I was recording side B of the cassette) and record the same 15 KHz signal using my Akai.
3. All 4 channels on the tape now contain 15 KHz tone.
4. Load this tape on Teac A-3340.
5. Connect 10Kohm resistor as the output terminals (output 1 and 4 as they are at the two opposite ends of playback head).
6. Connect oscilloscope on output channel 1 and channel 4 of Teac and make adjustment to Azimuth (as per the manual)

Repeat the same with 10 KHz tone.

Will this procedure work or help with playback head adjustment?

Regards
Annie

 

[WarmJetGuitar]

BUMP.

I'm pretty sure you need a calibration tape. I'm in a similar situation myself and I'm sure some of the experienced people in here can help you out.

 

[toddyjoe]

Your plan will not work for two main reasons. For one, because you recorded channel 1 and channel 4 in two different passes and in opposite directions, the odds are 359 out of 360 that the two tracks will be out of phase even if they use the same 15 kHz tone. Phase and frequency are two different things, and the only way you could ensure phase would be the same for all tracks would be to record all four tracks in one direction and in one pass using the same reference tone. Because azimuth alignment relies upon the test tones on the two compared tracks being 100% in phase, your adjustments will not be accurate.

For two, using a test tape created on another machine only means that your Teac will be calibrated to that other machine and only that other machine. Your Teac will not be aligned to any standard calibration and there will be no assurance that anything you play or record on the Teac will sound the way it is supposed to. It does not matter if your Akai has original and perfect-looking heads if the Akai itself has not been recently calibrated and aligned, and it is highly unlikely that even a perfectly-calibrated Akai consumer deck has adequate electronics and mechanics -- and a sufficiently flat and wide frequency response -- needed to create a usable test tape. That is why companies like MRL are not using Akai machines to create test tapes. Only an MRL or equivalent alignment/calibration tape has the necessary accuracy to objectively align and calibrate your Teac and without such a tape your alignment efforts will be no more accurate than if you tried to adjust using your eyes and ears.

Brand-new 1/4" MRL tapes can be had for about $100. I am not sure what the going service rate for aligning a Teac A-3340s may be but it might cost about the same. Unfortunately, alignment/calibration expenses are all part of joining the reel-to-reel club. Good luck and feel free to ask questions!

 

[Alfredo_S]

Hi Annie,
Anyone correct me if I'm wrong, but:
If the tapes you record are to be played back only on this same machine (and not on another 4 track machine), azimuth correction might not even be necessary.
You could however check if the record and playbackhead are properly aligned by scoping the monitor (playback)outputs 1&4 while recording the test tone.
Then (if necessary) you can simply adjust the playback (or record) head and you should be fine.
If errors are too great however, you'd better use a dedicated alignment tape.

Good Luck,
Alfredo