A problematic Teac X-2000R

2014-03-31 18.59.39

Recently I obtained, for a fair price, a Teac X-2000R. It is a stereo reverse deck, with 6 heads, which means it will record also in reverse. It has dbx built-in, and it can use (chromium) EE tape. A digital counter in hours, minutes and seconds and bias fine tuning on the front panel is also provided. It has 9,5 and 19 cm/s speeds.

Dual capstan

Another prominent feature that is has, however proved to be a very problematic one. The deck is equipped with 2 capstans. This feature was introduced into the later tape deck models, almost towoards the end of the tapedeck-era, to further improve tape-head contact and wow&flutter. These assumptions are correct, and they work well when the deck is in new condition and everything is well calibrated and up to specifications.

On this deck however, things were not new and not up to specs. The dual capstan design is a challenge in itself, but things are further complicated by the fact that it has to function in reverse as well. On this unit that is accomplished by a belt that ‘travels’ across different parts of the flywheel that varies in diameter.

Problems

After the initial cleaning, optical and technical/mechanical, it soon became apparent that the tape handling was not up to par. Sometimes the tape would ‘run away’ from the heads a bit, resulting in loss of audio or worse: tape jam. Things were even worse when playing in reverse. I soon found out (through the service manual) that there were adjustments to be made to the tape tension.

Tape tension

But the increased tape tension was not the solution. When it was ok in forward play, it was bad in reverse. Or vice versa. Or it differed when loading large reels (26 cm) compared to 18 cm reels. Or it was different with different brands of tape. And that wasn’t even reproducible across sessions. And the next day it would be different again.

Solution

Of course the first thing I did was to change the belt. I have a blog of that action, but it is in dutch. So here it is, sorry only in dutch:

====== BEGIN OF DUTCH TEXT ======

Nou, de siem-snaar was snel binnen, en vanochtend was het toch regenachtig, dus aan de slag gegaan met het vervangen van de Teac X-2000R snaar.

Ik heb de uitbouw gedaan volgens de foto’s in deze thread, daar heb ik heel veel aan gehad:

http://www.audiokarma.org/forums/showthread.php?t=59729


Daar wordt behandeld een X-1000R, en die blijkt toch niet helemaal hetzelfde van binnen. Ik kwam meteen al een grote print tegen die in de weg zat, deze is er niet in een X-1000.
Hierdoor kon ik niet bij de bovenste schroeven komen van de plaat waar de capstanmotor op vast zit. De print moest dus los en daarna omhoog gelift worden, er zitten helaas te veel kabels aan vast om hem compleet uit de weg te krijgen.







Na wat kabelbomen losgeknipt te hebben, kon ik de print opbeuren en omhooghouden met een plakbandrol.





Hierna kon ik er wel goed bij.





Nog even de plaat losknippen van de motor zelf:



Er zitten alsnog wat kabels in de weg, maar die zitten gelukkig vast met connectoren. Loshalen die hap dus.





Eindelijk uitgebouwd. De 2 vliegwielen in de achtergrond:



De 2 vliegwielen verwijderen. Goed links en rechts uit elkaar houden.



Overigens viel me meteen op het grote verschil tussen de snaren: de oude is een stuk langer dan de nieuwe. Dus of de oude was wat uitgerekt, ondanks dat het rubber nog vers aanvoelde, of de nieuwe is ietsje te krap. Of allebei.

Toen heb ik alles losgehaald en schoongemaakt en opnieuw gesmeerd: de vliegwielen, de aandrukrollen en het aandruk mechanisme. Oud vet verwijderd, nieuw vet er op. 

Alles zeer grondig schoongemaakt. Vliegwielen er weer op, meteen de washers aan de voorkant weer over de capstans gedaan. Nieuwe snaar er op:



En toen alles in omgekeerde volgorde weer vast. Het was een beetje pielen om de snaar weer over de motor te krijgen, maar het ging uiteindelijk wel. Als laatste de print weer laten zakken en vastgezet.

====== END OF DUTCH TEXT ======

Unfortunately this was not the solution that fixed it completely, although the situation improved a bit. Even increasing the tape tension to incredible heights (or incredible lows) did not fix it. So I went online to find a solution.

Several fora messages suggested that everything in the tape path was relevant to my problem. From tape guides, to the rubber idle rollers, to lubrication of the tension rollers, to the state of the rubber of the pinch rollers. From the tape tension to the smoothness of the tape in question. It seems that everything was related to weather the dual capstan principle would function correctly.
So I soaked the pinch rollers in detergent for one night. The rubber was much softer and grippier after that treatment. Again, a little improvement, but no permanent fix.
I switched the pinch rollers from left to right, to see if that would improve the situation. No way.
I lubricated all the moving parts, I installed the little O-rings that were required for the rollers to function correctly (expensive little buggers!). Still there was no definitive solution that worked all the time.

Meeting

In April I went to a meeting of fellow tape deck enthusiasts where there was an opportunity to work on decks. I tagged the deck along, and fortunately there was an expert who was willing to take a look at the Teac. Immediately he found one problem: I had put the tape tension way too high. We measured more than 100 gr. when 50 was required. He used a Tentelometer, a very rare instrument which he posesses. It looks like this:

After we adjusted the tension to 50 grams, the tape handling was still not good. In fact, it was worse. Then, the guy helping me thought the problem might be in the capstan motor, of which the carbon brushes would have degraded over the years resulting in less powerful drive. So, on the fly he opened the capstan motor, removed the old brushes and (he had them available) installed new ones.20140412_145008 20140412_144659After this, still no good. But I had new carbon brushes! Jeey!

At the meeting we came to the conclusion that maybe the new belt I had put in was not an original Teac spare part but a fake. So I went to an official Teac repair center and got myself an original Teac approved belt. After I installed that belt, still not any better. Grrrr.

The solution!

Eventually, as a sort of last resort, I took the Service Manual and went through all the mechanical adjustments mentioned there. Some I could do, some I couldn’t. For instance, I haven’t got a spring scale necessary to measure torque. And then, finally, after I adjusted the pinch roller pressure to a much lower value, it suddenly all seemed to come together.
When I adjusted for a very, very low pressure of the pinch rollers on the capstans, even to the extend that I could very easily stop the tape when playing, the tape would indeed run fine along the heads and reverse play was no problem. So I adjusted for a little more pressure but anyway now it works great and I haven’t got any more tape issues.

Great sound

After that, I planned to calibrate the deck. This also proved to be not as easy as I thought. The service manual mentions a lot of steps and I think I did them all 4 or 5 times. The problem was that the record calibration required EE or Chrome tape, which I did not have. Fortunately I could borrow a Maxell XLII tape from a friend.
Bu after I calibrated the deck using the EE tape, it did not sound good. The level was way too low. And when I recorded at a higher level, the amount of distortion was unbearable. Something was not right here. After advice given to me on my favorite forum, I used normal tape to do the calibration. It still wasn’t to my expectation. I’m not sure what fixed it, but I repeated the calibration procedure several times, and after that I found the recording to be very good!

EE (chrome) tape

So the deck was performing as it should, reversing as it should, handling tape as it should and now I was to test it with EE tape and with the dbx noise reduction and dynamic expander on.
The result was, well, as close tot the original sound as you can hope for. The high tones were beautiful, and the sound was quiet as a CD. Out of nowhere the music starts. This is tape technology at it’s finest. I am very happy with my new tape deck.

17 thoughts on “A problematic Teac X-2000R

  1. Michael Brenann

    Hello, In this report on your Teac X-2000R issues you mention that a friend had and installed new brushes in your capstan motor. I was under the impression that those brushes were not available so I would greatly appreciate it if you could tell me where they can be obtained. Thanks and best regards, Mike

    Reply
  2. Jaap Kroesschell

    Beste Philip,

    Dank voor het delen van je kennis en ervaring. Ik heb je blogs met veel plezier gelezen, en veel geleerd. Ik heb zelf recentelijk een bandrecorder aangeschaft, en verheug me erop ermee aan de slag te gaan komende zomer. Je schreef over een bandrecoder gebruikers / enthousiastelingen group, zou je me hier een link van kunnen doorsturen? Ik heb nl. (nog) geen calibratie tape, en andere tools. Misschien kan ik via die club iemand vinden die een calibratie band voor me kan maken op een gecalibreerde machine (ik ben immers een amateur, geen pro).
    Blijf vooral vloggen/bloggen!

    Met vriendelijke groet,
    Jaap

    Reply
  3. Alain Deneef

    Hello, do you have a source for these carbon brushes in the capstan motor? Did this person remove and replace the carbon pad only (how do you attach the new carbons?), or the complete assembly with the copper spring blades?
    Thanks,
    Alain Deneef

    Reply
    1. Philip van der Matten Post author

      Alain,

      The friend had made the new brushes himself, by filing a larger piece that he had obtained somewhere so that it would fit in the motor. So it was just 2 very small pieces of carbon that were installed into the copper tabs. They are held in place by the tension.

      Reply
  4. Jere Brewer

    My Teac X2000R has the same problem as described, especially in reverse play. I have the service manual and just to understand correctly what you did, there is an adjustment to the pinch roller pressure stroke adjustment nut. Is this what you adjusted to fix the problem? The manual says to adjust to 1.0 mm clearance between the pin and stopper cushion. Did you adjust to this clearance or just adjust to lesson the overall pressure? There is another section that is titled pinch roller pressure measurement but it only describes how to measure the pinch roller pressure and says if it’s not in the specified range you must replace defective parts, there are no adjustable parts. So, I just wanted to get clarity as to what you adjusted, hoping that I can fix my tape deck’s problem as well. Thanks.

    Reply
    1. Philip van der Matten Post author

      Hello Jere,

      This blog I have written many, many moons ago and since then I have fixed a lot of other devices. So, I can not recollect what I did exactly, but I can tell you that indeed the nut on the top of the deck was the solution. I think I recall that I adjusted it for a setting in the lower part of the ‘pressure-scale’ :), you just try that.
      I think that makes sense because the pulling capstan should be able to pull the tape to the point where it is tight between the 2 capstans. It works in unison with the forward tension. And if the pinch roller pressure is too tight, it won’t be albe to do that.
      Hope that helps a bit. Just keep following the SM to the letter, and try some setting, eventually it will work. But remember ALL the components need to be in good working order. It is NOT just 1 thing that fixes it.
      Good luck.
      -Philip.

      Reply
  5. Jere Brewer

    Hi Phillip,

    Thanks for the fast reply. I am going to give the adjustment a try and see what happens. So glad to find your website while researching the problem. I too have already tried various remedies but with no success and it only does this in reverse play, no problem at all in forward play. On a bit of a different subject what is your opinion on replacing all electrolytic capacitors in a tape deck? My X2000R is probably my youngest tape deck and my oldest is probably fifty years old. The oldest one, I did recap and really can’t tell any difference in the performance of the deck, but every capacitor I took out showed much higher capacitance , on the capacitor meter, than what it should be. Also, it’s very time consuming to replace them all, I spent maybe a month working off and on when I had time. Some guys say if it’s not broke don’t fix it, while others say it’s a ticking time bomb to leave the old capacitors in there. Just wondering what your thoughts are on the subject. Thanks again for your help, and I will let you know if the adjustment helps fix the problem.

    Reply
    1. Philip van der Matten Post author

      Jere,

      Glad you like my blog.
      Please check http://www.tapeheads.net/showthread.php?t=43728 as well, lots of good info there.
      About the caps: I am not an authority on electronics, far from that, but there is truth in both views, as always. I could not agree with you more that it is very time consuming, and the fact that most values are off when you check. One sometimes wonders how it could operate at all.
      I usually let the internet speak: some models are known for their bad caps, or other problems, and that is then well documented in the community. So I foloow that.
      Fun fact: I have replaced caps in a 4-channel amplifier from ’74, but only on 3 channels. Replaced the transistors also. All with new good parts. Then I measured the thing: nothing I could distinguish channel 1-3 from 4. So what was all the trouble for? Maybe the ticking timebomb thingy. Anyway, I had fun.

      Reply
  6. Rob Rivet

    Is there a place I can bring my X-2000R rather than try to fix it myself? Somewhere in the metro-Boston area?
    I am somewhat handy with most mechanical things but electronics require a gift I do not possess.

    Reply
    1. Philip

      Rob,

      What is the problem? Sometimes it is easier to fix than you think.
      Best is to try the tapeheads forum, http://www.tapeheads.net/forumdisplay.php?f=4 , which is full of the most experienced people willing to help.
      You can browse through the posts or search in them and you should probably find a member in that area. If not, you can always make a new thread describing in detail the exact problem you experience with your recorder, and then the experts will jump in and help you eitherway.

      Good luck!

      Reply
  7. Johan

    Nou Ik wilde er net een kopen ik blijf lekker bij de robuuste a 3300 serie. Ja ik moet zelf de de spoelen omdraaien is ook wel weer leuk om te doen.

    MVG Johan

    Reply
  8. Spencer

    If the tape is drooping in only one play direction, it is critical that you observe the belt in operation– it should run on the ridge of one capstan pulley and the flat of the other in one direction, and when the play direction is reversed, the belt must shuttle on to the opposite ridge and flat. This creates a slight difference in speed of the capstans ensuring tape tension on the heads. There are a couple of reasons the belt might not shuttle– wrong size belt, either length or width. Also, there is a certain amount of play that is required in the capstans, which is adjusted with the nut and bolt on the thrust plate (the end of the capstan sits in the bearing on the other side of this bolt). If the clearance is too tight on one or both capstans the belt will not shuttle.

    If the tape droops in both directions, the capstans may have been reinstalled on the wrong side.

    Reply
  9. ASIM MASOOD BUTT

    HELLO MY SELF ASIM MASOOD BUTT FROM AZIZ JEHAN BEGUM TRUST FOR THE BLIND WE HAVE TWO SET OF TEAC 2000 R BUT UNFORTUNATILY BOTH SYSTEM CAPTION MOTOR BELT ARE BRITALE AND NOT AVAILABLE IN LAHORE PAKISTAN SO TELL ME CAN YOU ARRANGE IF YES SO HOW TO PROCEED FOR THIS MATTER
    REGARDS
    ASIM MASOOD BUTT
    +923004255113

    Reply
  10. ASIM MASOOD BUTT

    HELLO MY NAME IS ASIM MASOOD BUTT I REPRESNT AZIZ JEHAN BEGUM TRUST FOR THE BLIND AND WE USE TEAC 2000 R SPOOL TAPE RECORDER BUT UNFORTUNATLY BOTH SYSTEM CAPTION MOTOR BELT IS BRITTLE AND NOT AVAILABLE IN LAHORE PAKISTAN SO CAN YOU ARRANGE IF YES SO TELL ME HOW TO PROCEED
    REGARD
    ASIM BUTT
    +90-300-4255113

    Reply

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