Opinions on Sony SLV-R1000 VCR?
 

I found a listing in the $500 range for a truly refurbished Sony SLV-R1000 by a highly rated seller. I'm not finding anything about the model in forum search. What's your experience?

I don't have an opinion on the unit, but if you're willing to spend that kind of money, I would strongly consider one of the approved VCR's from the VCR Buying Guide on this forum.

It's just not that good of a deck.

If you already have a quality with-TBC JVC, and a Panasonic AG-1980P as secondary, yet still feel the need to collect other-brand VCRs, then I say go for it.

My recipe is:
- 1st = JVC S-VHS with TBC, all-around best
- 2nd = Panasonic AG-1980P, for EP, VHS-C, linear audio, etc -- noting JVC can be fine at EP/VHS-C/linear too
- 3rd = another JVC S-VHS, but non-similar/different model
- 4th = other high-end models, but mostly for fun/play more than serious use/work

Jumping straight to a Sony like this would be a mistake, bad use of funds.

Also don't trust eBay feedback. Negatives are quite easy to get removed, which most people do not realize. The system has been gamed for years. And anybody selling dozens/hundreds of "serviced" VCRs is full of crap. Don't fall for it. In the 2020s, it's not an easy task for one person to do more than 1-2 decks per week, if truly servicing everything.

Thanks, that's the answer I was looking for!

I am curious about JVC linear sound problem.
Most family/private VHS (large part of digitization projects)are recorded with linear sound, not Hi-Fi.
I did not noticed difference between JVC HR-S7722/7711 and Panasonic NV-FS200.
And test cassettes show about the same result (however I did not tested full audio spectrum, only basic 100hz 1000hz 10Khz).
Where lie the problem of JVC?

From what I've seen, heard and discussed on this forum over recent years it's poor signal to noise ratio due to multiple tonal harmonics added by the VCR at playback. It seems JVC (on certain models) arent the only ones either.

Testing frequency response isnt enough. We have to test broadband noise performance in playback re the reference signal. This is a common test with solely audio tape gear, or should be.

My guess is SMPS and possibly video head drum motor. I see even in some mid priced Sonys (EZ77) the SMPS is nicely shielded inside a metal enclosure, whereas a JVC 7600 SMPS appears to have no shielding.

These things can happen when people are recommended VCR's solely or mostly based on their picture playback, forgetting the equal importance of audio playback, especially linear/normal audio which as you say was commonly used on many valued recordings.

Thanks for info! I did not noticed problems with SNR for 7722 and 7711. But I will check more carefully.

-- merged --

If we compare the manufacturer specifications of the HR-S77xx and Panasonic NV-FS200, we see that Panasonic has specified only the parameters of Hi-Fi audio - dynamic range better than 90db, frequency range 20hz-20khz etc. JVC is more precise (or more honest?) - specifying SNR 45db (which does not go with Hi-Fi at all, and JVC's SNR is not 45 db at Hi-Fi of course, it is better) and Normal audio frequency range 70hz-10khz. I believe this worth a test.

I have Panasonic linear audio test cassette 6khz/ 400hz-8khz-15khz. However not sure all frequencies are still up to specs. But at least it is possible to compare Panasonic & JVC. I am really curious :)

Attachment 19851

Linear audio can be tweaked on JVC VCRs, I've done it. I was willing to tweak every tape if needed but when I adjusted it to the optimal position for few tapes it ended up staying that way as it didn't sound as bad as it used to be anymore, So I guess over time the head stack goes out of alignment due to fast forwarding and rewinding or it was never adjusted perfectly at the factory. Either way it plays all tapes satisfactorily now.

Of course azimuth can be tweaked on JVC VHS decks and to my knowledge on every VHS and Beta deck ever made. Below is a diagram of the exact screw (and normally the only screw) to be carefully turned on a JVC 7600 ACE head, but I believe this position is the same for a number of JVC VHS decks.

This assumes that without even checking each tape, all were recorded to the 90 degree azimuth standard. We have no basis for assuming that until we check it. Our VCR may now be adjusted to 90 degrees but the tapes we play now and in the future may not have been recorded at that standard angle.

We check it by adjusting it, which means misadjust it to sound worse, then rock it through the peak alignment point a few times then carefully narrow it down to the peak point, normally the sharpest, clearest sound. Just as we did when tuning video tracking for peak RF signal on older VCR's before auto tracking was introduced on later model VCR's. (Below picture of front panel tracking adjuster on old Betacord deck). To my knowledge, unfortunately automatic linear audio azimuth adjustment has never been offered on any VCR or VTR so I assume we have to adjust it manually on every deck.

To explain a little more, unfortunately with video head tracking, the manufacturers could not tighten the tolerances enough, so they had to provide the consumer front panel manual Tracking Control. It's the same with linear audio azimuth especially at the very slow tape speeds. The production tolerances could not be made that tight. Hence the need to tweak azimuth. Again we cant be certain a deck's linear audio azimuth is peaked on a given unknown tape unless we adjust it for that peak. If on some tapes it turns out that the azimuth was correct before our adjusting, we now know that for certain.

I suspect that if there was a manual linear audio azimuth adjuster knob on the front panel of every VCR, even better, on the VCR's remote, a whole lot more digitizing folk would be twiddling it, because it would be so safe and easy to twiddle it.

By all means test it. Remember that signal to noise is not the same as playback frequency response but each complements the other. A useful signal to noise test tape has reference tones punctuated by silent sections. In an excellent playback of these silent sections, we hear nothing but the tape's own hiss. This mere tape hiss shouldnt be confused with the VCR's play preamp hiss, as the two hiss types can sound similar.

What I meant is JVC linear audio can be improved by adjustment as the factory position can't be relied on, Once adjusted to an optimal level on some pre-recorded tapes I found out that there is no need to do it again as most tapes exhibited an acceptable db level and noise floor compared to what it was before.

And gravity. :wink2:

I've said for for years. These decks are are all 20-30 years old now. Gravity takes a toll. I realign everything for that reason. It's time consuming. But once done, it tends to be done for years.

Although, yes, FF/REW/PLAY can have some nuanced affects, forcing premature re-realignment.

I'm not sure if static gravity can play any role here, the parts are way too light to have enough force to move the adjusting screws, If throwing the VCR from the 10th floor than yes gravity is devastating here. It's usually brutal force resulting from damaged tapes, mis alignment or broken parts that turn the electric motor force into self destructing force and also without forgetting the human force from abuse and misuse.

VCRs get misadjusted by mere millimeters. Gravity can definitely affect mm over decades.

It may depend on which 'most tapes' we're talking about. If they were initially recorded on only one or two well adjusted decks we mighty get away with it but if we're a business digitizing tapes from many different owners using many different decks and camcorders, I suspect the chances of the audio azimuths all lining up as very low, especially if recorded in LP or EP speeds.

That gave me a chuckle. :D

There's this line in The Big Short, where Steve Carell (based on real-life Steve Eisman) puts his hand in the air, and says "0%"

That's how I feel here. 0% chance it will be the same client to client. Does not happen.

At best -- and this is what I do -- you can have multiple decks with multiple offset presets. That way, you're not tweaking endlessly inside a deck guts, you just swap out to another unit. Odds of a deck working immediately is vastly more than 0% now.

I said pre-recorded tapes, means commercial movies, That means the head now is as close as it can be to factory position or 0 degree, Remember linear audio is mono with one head that is about 1mm wide, it's more forgiving for mis alignment than any other head in the VCR, Having said that it is important to have it in the best possible position which is 0 degree.

For tapes recorded on mis aligned VCRs, I have a VCR ready for tweaking but I rarely have to do that, As I said they all play crisp audio with good audio level and very low noise floor. and I'm not a super fanatic to readjust the audio head for every tape, that's insane, but I don't question people who do it, you can be fanatic about any hobby.

Especially if fat bottom fall on it :) But regarding audio head misalignment, nearly all VCRs I use was up to specs, even azimuth. And it is nearly impossible to align azimuth by ear if there are up to 10khz on home cassettes. When we digitize mono full track tapes, it is very simple to adjust azimuth - simply look at phase spectrum display and adjust (all my recorders has azimuth alignment) because they all are digitized as stereo with 2x 2,75mm channel width and later mixed to mono. But for VCR linear audio - adjust for maximum level at 10khz and leave alone. You can not hear +-few minutes misalignment for speech anyway. But you need original test tape for that to be sure. And do not forget this thing, it is very important for linear audio (and erase) heads, otherwise, if heads are magnetized, you can print hiss on tape and even erase high frequencies (and there is nothing like "self demagnetizing" any more (however it does not fully demagnetize them), because no one use them for recording):

Attachment 19862

It's considerably less forgiving than playing back with a linear stereo head: the two linear stereo tracks are about 0.35mm wide. On the other hand the wider track gives potentially less noise than the narrower stereo tracks.

You did not also mention the other equally important variable here which is linear tape speed. The slower the tape speed, the less forgiving of azimuth error. Standard VHS SP tape speed is 1.313ips (NTSC) or 0.921ips (PAL). That's slower than the standard Compact Cassette (1.875ips) and of course it gets slower. LP halves those speeds and then even slower, SLP and EP.

From Wiki: "... This speed is quite slow: for SP it is about 2/3s that of an audio cassette, and for EP it is slower than the slowest microcassette speed. This is widely considered inadequate for anything but basic voice playback, and was a major liability for VHS-C camcorders that encouraged the use of the EP speed."...

Unfortunately the Wiki article makes no mention of the added problems of azimuth misalignment the slower the tape speed. A given misalignment at SP speed might just make speech and music a little dull and more hissy, but at LP it will be worse, and EP even worse still. Speech can become not only dull but barely intelligible, with even more background noise.

This is the same set of problems encountered with audio magnetic tape well before Beta or VHS were invented. Nothing new here.

That's why getting the best results out of economical consumer formats can be actually harder than the more expensive and robust pro formats. It takes more expertise! Getting good, consistent results can involve more than just buying "the best" gear, banging in a tape in and pressing play.


For me to adjust azimuth at the beginning of a VHS tape takes me about 30 seconds max. Often a lot less. That's because I have built into a few of of my VCR's a basic, no frills external azimuth adjuster control (pictured).

So I dont have to:

1. open up the VCR,
2. find the correct azimuth screw (there is only one correct azimuth screw in each machine),
3. locate the correct non magnetic screwdriver for that screw,
4. adjust azimuth with the machine open and nothing to steady the screwdriver but my own hopefully steady hand, careful not to accidentally touch or damage parts inside the VCR especially the delicate spinning video head drum or the moving tape, and avoid to electrocuting myself by touching exposed high voltage components.

I dont have those problems or risks. There's just one external knob to adjust. In making a simple mod, I made it easier, quicker and safer, and at less than 30 seconds per tape, adjusting audio azimuth for each tape takes only a tiny fraction of the maximum playing time of the average tape, say 180 mins for SP and 360 minutes for LP.

I'm not saying that everyone should or could make this sort of mod. Maybe most cant. I'm just showing it can be done by those with the skills and it makes adjusting azimuth a lot quicker easier and safer.

Pictured a TOTL Nakamichi cassette deck with a front panel azimuth adjuster built in from the factory.

Pictured also is a professional Studer tape machine used in the record production business. Note the professional azimuth adjuster knob and matching scale, acting on the play head azimuth. Most pro studio tape recordings are more forgiving for a given azimuth error than SP VHS yet still these pro's have the adjuster fitted.

Also pro recorded tapes often have alignment tones recorded including for azimuth. This makes it easier. You could be stone deaf and still get the azimuth right just looking at meters rather than listening. No such luck with most amateur recordings. All we have is listening to whatever was recorded on the tape and align azimuth to that as best we can. (At least when using a mono track ACE head which is the most common). Another example where getting the best results from non pro audio recordings is actually harder. For here we have nothing but our listening skills to guide us.

You have wrong Studer. At least for reproduce :) But in case of your DIY VCR azimuth adjustment, keep in mind original azimuth screw thread does not allow to adjust azimuth N times and it is not precise. So you will never get back to initial adjustment without test tape. Original thread is coarse. You should make a knob/screw like original Studer, otherwise your screw will wear out very fast. Or with servo motor like on CR7 ;) And how you can adjust azimuth by ear for mono recordings with FR below 10khz I can not imagine (if head is not terribly misaligned).

I'm not sure what you're saying. Please tell me what I got wrong.

On the decks I've looked at the ACE head screws and threads usually are not greased ex factory. As part of the mod I grease them. Finer pitch screw threads might make things more precise but the large adjuster knob diameter essentially "gears it down" and in practice it's quite useable. If the pitch is too coarse how could the factory staff have ever aligned azimuth in the first place?


No need to. I adjust azimuth to each tape to be digitized. Each tape to be digitized is my "azimuth alignment tape".
I'm not digitizing standard alignment/calibration tapes. They make rather boring listening and so far nobody has asked me to digitize one. Of course if I ever sold a machine I would first adjust azimuth to standard.


Not sure what you're saying. Again in the absence of alignment tones I adjust using the content on the tape. What do you do? Do you have experience in adjusting azimuth without test tones, using all that is there, the tape's contents? Expert audio tape digitisers do it regularly.

Of course they do. I have 6 Studer A80, all speeds from 9 to 76cm/sec including 2x QC, A820, CR7, and they all has playback azimuth adjustment knobs. Original or made by JRF. But it is nearly impossible to adjust mono 1 channel azimuth by ear if recorded frequencies are below 10khz. +- 3 bogen minutes are not audible in this case even on VCR speed. If you want to mess with VCR linear audio head azimuth, order correct knob from John French. With fine thread stud.

Wrong. It can be if you digitize full track mono tape in stereo and align head in accordance with phase spectral display. In all other cases you should return to nominal azimuth before.

Of course we cant align to frequencies higher than the recorded frequencies because there are none there to align to. What are you referring to? Aligning to bias tones? Not likely on a VHS linear audio track.


I find this unintelligible. Again when a tape such as VHS linear audio was - for whatever reason - obviously recorded off standard azimuth, what do you do when digitizing it?

I only want to say - if recorded frequencies are below 10khz (speech) it is nearly impossible to adjust azimuth by ear for mono recordings. Except for music recordings, but VHS tapes with music recorded with linear audio is rare. For stereo you can switch to mono and adjust by ear on headphones very simply.

If azimuth is off +- 3 minutes I do nothing. And 99% tapes are in this range. Because it will improve nothing for linear mono audio. My heads (vcr ;)) azimuth is always at 90° adjusted in accordance with original test cassettes (what all are close to each other). In those very rare cases when azimuth is really off because someone is messed with head at recording, it should be adjusted. But this is what you can hear well immediately, because those sound like from WC. But it is rare.

And for those tests I have Panasonic NV-FS1 what I commonly use for rewinding. I do not adjust azimuth on my JVC or FS-200 if I am not sure there is azimuth problem, not simply how it sounds. In 99% if sound is like from WC, it is recorded that way.

Radiocom, I find it hard to relate to your description in degrees and minutes to actual sounds. For me it's simple. Having an external azimuth adjuster as pictured, there is no setup time. I can quickly and easily listen to a sample of any tape playback while slowly turning the adjuster to find the peak point in the azimuth curve. It normally takes very little time.

You claim that 99% of tapes were recorded to the azimuth standard. I would never rely on mere listening sans adjustment to judge whether there is azimuth misalignment or not, or to what degree. For me that's too subjective and unreliable. We have no reference except this unknown recording made on whatever unknown VCR or camcorder. Adjusting azimuth on any given tape from misaligned to aligned then misaligned on the other side, then back to the peak tells me whether it is aligned or not. Maybe my deck was initially aligned to the tape. Maybe not. Adjusting azimuth in and out of alignment confirms that one way or the other.
Why use an indirect method of assessment, which includes an unnecessary assumption, when a direct method is possible?

Yes monitoring in linear stereo and alternating with mono summed monitoring is useful as again it provides some sort of reference point, but many people dont have access to a linear stereo VCR, and many amateur VHS and VHSC tapes were recorded in linear mono. With no linear stereo playback and no easy and safe way to adjust azimuth, many people dont know how much better their linear audio could sound.

I am just trying to say that with your method you are likely to play tapes with a much larger azimuth error than if the head was adjusted to a test tape. Because you can not hear what the hell you are adjusting. So - no to your method.

And keep in mind - original azimuth screw thread wears out. Adjusting azimuth N times even when it is not necessary simply damage your linear head assembly. This is why I advice to have separate VCR (it can be your sharp for example with that knob) what you can use only for test purpose if there are suspicions something wrong with azimuth. And right method is to adjust azimuth to 90 degree in accordance with test tape first and only then reproduce particular cassette and adjust azimuth and try to hear what changes. Not "on the fly" from one tape to another.

P.S. One more example - for speech recorded on audio cassettes digitization I use Nakamichi LX-3 and 480 (restored of course) with removed erase head. There is no need to use CR7 or Studer A80QC for any crap. But this is not because there are no other dual capstan decks but because of possibility to adjust playback head azimuth N times (and pressure pad lifter of course). Those nylon screws does not wear out. And speech is recorded commonly in half track mono. So when reproduce in stereo you should not hear nothing - simply look at phase spectral display and adjust azimuth "on the fly" and mix to mono after digitization. But if there is "stereo" recorded, you should return to nominal azimuth with test tape and then try to adjust something or decide to leave it as is, simply applying digital phase correction after recording.

It's your claim. Please explain yourself. Give examples.

Maybe my English is not good enough, but I think I have already mentioned enough examples. I will draw your attention again that for a mono track played as mono, the azimuth can be adjusted only according to the maximum level of the upper frequencies played. However, if these frequencies are absent, or they are episodically present, then all the adjustment is based on the principle of "I think this is correct, because I heard it that way". This is not a constant test tone from test cassette, according to which you can adjust the maximum (or minimum, if the sound track is divided into two, recorded in counterphase) level. So if you decide to mess with azimuth, the first you should be sure there is azimuth error enough it worth correction (using separate test vcr for that purpose). And then on main VCR be sure azimuth is at nominal position first (or calibrate nominal azimuth in accordance with test tape first) and then make azimuth adjustments. After playback return to nominal adjustment with test tape. But never "on the fly" from tape to tape. But it is up to you - that's your tapes and your VCRs so you can do all what you want.

Thankyou. I thought that might be where you were heading but it's your point so it's right that you explain it.

Of course in such a case we are in a sense flying blind re correct azimuth at points where there is not enough HF content for fine alignment to them. But if there is not the HF content in certain passages, such fine azimuth adjustment no longer matters, for now there are not the relevent HF's to be lost through azimuth misalignment! This is "the cat chasing its tail"!

After such a recording we can only say, "Well if those HF's had been still there, those HF's would have been captured." ! It becomes a pointless exercise aligning for frequencies no longer there.

We can only align to the content on the tape at time of digitization.
As you say using a stereo playback head helps in such a situation because it's more forgiving re azimuth misalignment. I sometimes capture a mono tape in stereo while monitoring in summed mono, including keeping an eye on an Azimuth Corrector tool's live meter.

Not because it is more forgiving but because you can exactly align correct azimuth on the fly and loose nothing. It is very simple - start Adobe audition phase spectral display, start 2 channel recording and adjust azimuth in seconds. After recording mix both tracks to mono.

In 80s most tape recorder manufacturers, including Studer and Otari stopped or limited full track head manufacturing. At least when I bought last new Otari MTR-15 fom Otari GmbH in early 2000s, they told me mono heads (I was interested in full track recording heads) are not produced long time ago, only old stock maybe is available in Japan. Instead of this for full track (6mm track width) mono was used stereo heads with each track width 2,75mm with mono/stereo switch (that 0,5mm gap between tracks affects nothing in real life).

For stereo azimuth adjustment switch to mono and you can adjust azimuth with ears very precise because of phase shift. + control on spectral display.

P.S. Some useful resources (however I am sure we hijacked this thread, it is no more related to OP Sony) :):

https://mrltapes.com/mcknight_azimuth-in-mtr.pdf

https://richardhess.com/notes/2006/0...hows-and-whys/

But the narrower tracks in a stereo linear audio head are more forgiving because the stereo pole pieces are narrower! This is no small thing. As Latreche stated earlier the standard linear audio track is 1mm wide. At only 0.35mm wide the linear stereo R/P heads are almost 3 times narrower. They are less sensitive to a given azimuth error because they sample a shorter wavelength. We can have a great playback head with sub micron gap length but unless azimuth is aligned to that same micron level of precision that head's fine resolving ability is wasted.

Especially for people without the skills/confidence to open up a deck and tweak the linear azimuth to a tape, this is an audio quality advantage. Played on a deck with a linear stereo head many tapes especially LP/SLP/EP which sound muffled on their linear mono head deck will sound considerably clearer. Many which sound only moderately muffled on a mono playback head will likely be reproduced with little or no HF loss on a linear stereo head.

Speaking of relevence to the original post, the Sony SLV-R1000 SVHS deck may have this linear stereo AC head. But this information isnt always made clear in owners' and service manuals.

If I was searching for a VHS VCR with good linear audio especially for LP/SLP/EP recordings but could not tweak the internal AC head azimuth I would be looking at a good quality deck with a stereo linear audio head. Unfortunately in video digitizing discussions this factor is rarely if ever mentioned. What would help people choose a suitable VCR for digitizing their tapes and who cared about audio quality is a list all the quality VHS machines which have the stereo linear AC head. Especially so for the LP/EP/SLP recordings. This factor could be incorporated into existing lists.

I much prefer these discussions to include sharing of actual audio and video examples. So trying to lead by example here.

I may have shared this audio before. LP mono linear original audio, captured with mono linear head, custom azimuth aligned by ear. Being a PAL recording this LP track runs at even slower tape speed than NTSC LP. Actually a quarter the speed of a standard compact audio cassette. This is from a roughly 6 hour long VHS E 180 tape.

No audio processing/ restoration used here. Straight off the tape.

Is azimuth alignment critical here? Is the Pope a Catholic?

Apologies for the late reply directly to your enquiry. I'm a service technician. I have no direct experience of this machine but here's a link to a video from an experienced technician familiar with servicing them. He has a high regard for this high end model while noting a few problems with a machine which he proceeds in the video to repair. Hope this helps.


https://youtu.be/0XMh7NKjzng?si=Q4kVEfZAmbO36A5z

radiocom, I've been puzzling over various things you've said about azimuth in this thread, and wondering if there is a simple solution here.
Is it possible your VCR has only mono linear audio, not stereo?

In your case, it is impossible to say this because there is no reference point (azimuth adjusted to 90 degrees according to the test tape) and then the particular tape was played with the nominal azimuth, then +1min+2min, -1m-2m, etc. In your file main high frequency is 4khz, at peaks 8khz so azimuth adjustment (for LP) is useful if error is more than about 1 minute.

radiokom, in your post #29 above you cited a Richard Hess article: "Azimuth: Hows and Whys." Thankyou. I reread it.

You might care to read Richard's first paragraph, which I have copied here.


"There is a recurring question as to what is the best way to set azimuth for playing a tape. Many people assume that using the test-tape alignment is best. Well, that makes another big assumption: The recorder used a proper test tape alignment. While that can be the case, it usually is not.

If the tape has tones on it (a big if in many collections), you align to that, right? Better, but consider this: When a 1963 album was being remastered, the mastering engineer aligned to the tones and after doing all his magic found that the tones were not recorded at the same azimuth as the program. Big redo!

Aligning to the track material itself is the only way to properly adjust azimuth in the absence of tones and it is still necessary to check the track material even if there are tones. The wider the track and the slower the speed, the more critical the azimuth adjustment is. Stereo makes it more critical and often times easier to adjust..." *

author Richard L. Hess, Audio tape restoration, Canada

*(My underlining).

You should read all article and understand what is written.
This for example:

If you have a mono tape, that’s all you have, but if you have a stereo or multi-track tape, you can sum channels that have similar program on them that should be in phase and get a wider baseline for tweaking the azimuth.

It seems that you simply consider your azimuth adjustment method to be correct and protest if anyone challenges it. ;)

He's talking about a stereo or multitrack tape. I assume he means using a matching multitrack head to read that tape, and then summing tracks with the same content for as he says a wider base for more accurate azimuth alignment. That makes sense to me. It allows better summing of the similar tracks to potentially reduce tape noise and dropouts. But again is your vcr linear head actually stereo or is it mono? Why not check this?

There is nothing to check, linear audio for all S-VHS decks we (I) use (Panasonic NV-FS200, HS1000 JVC HR-S77XX series etc.) is 1 track mono.

P.S. I have few professional Panasonic with stereo linear audio and Dolby B, but they "belongs to the museum" © :).

P.P.S. Although - one idea came to my mind as a result of this controversy. To use a professional Panasonic with a stereo head for accurate determination of azimuth error. If until now I did it "by ear" on the NV-FS1 and then decided it worth alignment or not, then by playing a mono track on a VCR with a stereo linear audio head, the azimuth error can be determined in a few seconds using the phase spectral display. And then decide there is a reason to mess with adjustment or better to leave it alone.

I suspected they might be mono. So you know you can't capture in stereo and compare time alignment of left and right tracks? I thought you might have seen the identical left and right waveforms and wrongly assumed azimuth was correct for that tape, and almost every other tape you played. Oh well I tried to help. Now I'm confused again as to what's going on.

Relax, I own a professional sound restoration studio and have some experience with azimuth for more than 35 years :) But as I wrote in edited comment above, it would be a good idea to use professional VCR I already have with stereo head to determine azimuth error in seconds.