Tape transfer to digital question

[knobtwiddler]

I think there are quite a few determining factors as to whether you ought to dive in and tweak azimuth on a deck that wasn't designed to offer it as a user adustment. One of them has to be whether your deck has a fierce solenoid. Ironically, Naks (which make it easy to adjust AZ with a mini driver, or in some cases give you a knob to control a servo that does it) used a cam that raises the head block slowly and delicately. I am very fond of my Sony 666 and 777 decks, but they make a loud clunk when the block is raised. In this latter case, you really want the varnish on the screws or I suspect AZ will drift over time due to solenoid shock. I haven't proven this hypothesis, but I think there are grounds to suspect it'll happen if your solenoid is fierce.

[TIMTAPE]

If your 666 and 777 Sony's have the same mech as my Sony 555 they aren't very convenient for adjusting azimuth anyway. As for adding a custom front panel adjuster even more difficult. Not designed for it. Teac/Tascam and probably others made consumer and pro cassette decks with motor and cam driven head sled/pinch roller etc engagement. Then of course the classic Naks. These Naks didn't even use sealing paint on the head screws. The adjuster screw heads are serrated and a tiny plastic arm lightly holds them in their detent positions, like some HiFi amp tone control pots have detent positions in say 1db steps. In addition I often paint my own marks on adjusters and the base plate so I know what is the nominal reference point. If they have moved I can see it easily. Again when playback for transfer is the only mode in view, azimuth is determined solely by each tape played, not by the azimuth reference tape. It's a short term adjustment only, never intended to be set in stone. But if you think your Sony heads might change azimuth from the vibration of the solenoid, why not test your hypothesis? Remove the screw sealant, paint a temporary alignment mark on the screw head for reference, engage the solenoid multiple times and observe the results.

[knobtwiddler]

Hi Tim,

>666 / 777 different to 555

I think all 3 models are pretty different. The TC-K666ES is unique in that it has DD / QL reel motors (only Revox and a couple of other German OEMs had that feature). There are several models of 555, and I suspect that they are different to the 777 models (of which there are 3, which each have slight differences). None of them make AZ tweaking easy (you have an inner screw, with an outer locking collar).

If I need PB azimuth, I use my Naka CR-70 (JDM CR-7). The interesting discovery for me has been that, after much research and being fortunate enough to be sent a mint example by a friend in Japan, I have found the PB azimuth control less useful than I expected. On the occasional rogue tape that has terrible alignment it's been invaluable. But that's only been one or two tapes so far. I do very little recording and the CR-7 was gotten for archival purposes. I've checked my azimuth servo with a scope and it works well. But I think - as Ted has intimated - that the usefulness of the PB azimuth servo is dimished somewhat if you have top-notch tape handling. The CR-70 has less take-up-tension and back tension than any other machine I own, but it also measures the lowest W+F. I had a B215 for a time and I felt a similar way about it, i.e. top end clarity was exemplary, and the azimuth knob wasn't really needed. I can imagine that with single capstan machines, were I to have one with an azimuth knob, I'd be using it a lot more often.

[TIMTAPE]

Originally Posted by knobtwiddler

Hi Tim,

>666 / 777 different to 555

I think all 3 models are pretty different. The TC-K666ES is unique in that it has DD / QL reel motors (only Revox and a couple of other German OEMs had that feature). There are several models of 555, and I suspect that they are different to the 777 models (of which there are 3, which each have slight differences). None of them make AZ tweaking easy (you have an inner screw, with an outer locking collar).

The specific problem I alluded to re my 555 was the cassette carriage mechanism. Like other cassette machines a hole is provided for a screwdriver to adjust azimuth but once the screwdriver is inserted, you cant see the screwdriver point or the screw head you're meant to insert that screwdriver blade. Even without the screwdriver inserted it's still very hard to see inside. Then if the tape happens to end and the machine stops, there's risk of damage to the machine as the azimuth screw goes flying back to its resting place with the screwdriver still attached to it. Change the screw head to an Allen head type and the problem could become even worse. Is seems like an afterthought. Not suitable for serious azimuth correction work. Making this feature work better would involve probably a lot of messing around.

Originally Posted by knobtwiddler

If I need PB azimuth, I use my Naka CR-70 (JDM CR-7). The interesting discovery for me has been that, after much research and being fortunate enough to be sent a mint example by a friend in Japan, I have found the PB azimuth control less useful than I expected. On the occasional rogue tape that has terrible alignment it's been invaluable. But that's only been one or two tapes so far. I do very little recording and the CR-7 was gotten for archival purposes. I've checked my azimuth servo with a scope and it works well. But I think - as Ted has intimated - that the usefulness of the PB azimuth servo is dimished somewhat if you have top-notch tape handling. The CR-70 has less take-up-tension and back tension than any other machine I own, but it also measures the lowest W+F. I had a B215 for a time and I felt a similar way about it, i.e. top end clarity was exemplary, and the azimuth knob wasn't really needed. I can imagine that with single capstan machines, were I to have one with an azimuth knob, I'd be using it a lot more often.

I agree a high quality dual capstan cassette deck will probably have better azimuth stability in both the short term and the long. But this very strength on its own, and when playing back tapes made on similar decks, can be a liability when transferring various cassettes recorded originally on various modest and definitely NOT dual capstan cassette machines, especially when presenting such a recording in its original mono (or summed mono) state (advantages of lower tape dropout and potentially lower tape noise). I've transferred many such cassettes and seen and heard the phenomenon many times.

I still use my dual capstan Nak transferring such cassette tapes but while I transfer both mono and stereo tapes in stereo, I've always monitored with the ability to switch between stereo and mono where the first sign of the onset of azimuth related comb filtering in mono is most audible, and I can gently, manually, nudge the play head back on track. The software takes care of the remaining inter channel errors.

I guess a Dragon would track such azimuth drift as even though it is reportedly quite slow in responding to azimuth changes, we're talking about original recordings with a slow drift anyway. But I'm not about to buy a Dragon any time soon.

So again, absolute azimuth accuracy can be a liability, creating an increasing azimuth drift error re the tape being digitized. We can often digitally time align left and right channels for minimum comb filtering, but we cannot recover azimuth error within the left channel or within the right channel, and in my experience the error can be that much, when using our top of the line dual capstan deck. The high spec deck basically tracks down the centre of the road when the actual tape recording can be subtly heading off in another direction!

[TIMTAPE]

[QUOTE=TIMTAPE;1515524]

Originally Posted by knobtwiddler

Hi Tim,

>666 / 777 different to 555

I think all 3 models are pretty different. The TC-K666ES is unique in that it has DD / QL reel motors (only Revox and a couple of other German OEMs had that feature). There are several models of 555, and I suspect that they are different to the 777 models (of which there are 3, which each have slight differences). None of them make AZ tweaking easy (you have an inner screw, with an outer locking collar).

The specific problem I alluded to re my 555 was the cassette carriage mechanism. Like other cassette machines a hole is provided for a screwdriver to adjust azimuth but once the screwdriver is inserted, you cant see the screwdriver point or the screw head you're meant to insert that screwdriver blade. Even without the screwdriver inserted it's still very hard to see inside. Then if the tape happens to end and the machine stops, there's risk of damage to the machine as the azimuth screw goes flying back to its resting place with the screwdriver still attached to it. Change the screw head to an Allen head type and the problem could become even worse. Is seems like an afterthought. Not suitable for serious azimuth correction work. Making this feature work better would involve probably a lot of messing around.

Originally Posted by knobtwiddler

If I need PB azimuth, I use my Naka CR-70 (JDM CR-7). The interesting discovery for me has been that, after much research and being fortunate enough to be sent a mint example by a friend in Japan, I have found the PB azimuth control less useful than I expected. On the occasional rogue tape that has terrible alignment it's been invaluable. But that's only been one or two tapes so far. I do very little recording and the CR-7 was gotten for archival purposes. I've checked my azimuth servo with a scope and it works well. But I think - as Ted has intimated - that the usefulness of the PB azimuth servo is dimished somewhat if you have top-notch tape handling. The CR-70 has less take-up-tension and back tension than any other machine I own, but it also measures the lowest W+F. I had a B215 for a time and I felt a similar way about it, i.e. top end clarity was exemplary, and the azimuth knob wasn't really needed. I can imagine that with single capstan machines, were I to have one with an azimuth knob, I'd be using it a lot more often.

I agree a high quality dual capstan cassette deck will probably have better azimuth stability in both the short term and the long. But this very strength on its own, and when playing back tapes made on similar decks, can be a liability when transferring various cassettes recorded originally on various modest and definitely NOT dual capstan cassette machines, especially when presenting such a recording in its original mono (or summed mono) state (advantages of lower tape dropout and potentially lower tape noise). I've transferred many such cassettes and seen and heard the phenomenon many times.

I still use my dual capstan Nak transferring such cassette tapes but while I transfer both mono and stereo tapes in stereo, I've always monitored with the ability to switch between stereo and mono where the first sign of the onset of azimuth related comb filtering in mono is most audible, and I can gently, manually, nudge the play head back on track. The software takes care of the remaining inter channel errors.

I guess a Dragon would track such azimuth drift as even though it is reportedly quite slow in responding to azimuth changes, we're talking about original recordings with a slow drift anyway. But I'm not about to buy a Dragon any time soon.

So again, absolute azimuth accuracy can be a liability, creating an increasing azimuth drift error re the tape being digitized. We can often digitally time align left and right channels for minimum comb filtering, but we cannot recover azimuth error within the left channel or within the right channel, and in my experience the error can be that much, when using our top of the line dual capstan deck. The high spec deck basically tracks down the centre of the road when the actual tape recording can be subtly heading off in another direction. To the credit of the Nak Dragon designers, at least the Dragon tries to follow it!