yet another 688 speed issue thread

[Bobby Darko]

take it apart alreadY!

No seriously, I guess I'm up to it too real soon, since I own 3 of these and none has had a belt changed in almost 20 years. Same goes for the roller...They do still work perfectly though. Great machines!

 

[heatmiser]

heat...

You go, man.

Great pics. Love seeing pics of other's setups. Your SG and Ampeg combo are sick. I had a chance to borrow a vintage Ampeg B50 valve bass combo once. It sounded incredible. That SG is a keeper huh???

Also, never enough pics of 688's. I'm glad you took the time to put them up.

Here...this is a thread with some detail about opening up a 424mkII. It will most certainly have loads of differences from opening your 688 up but there might be some applicable generalities: https://homerecording.com/bbs/showthread.php?t=289340

This is maybe a first, but I have to differ from cjacek on the condition of your pinch roller. It looks hardened. Some of the rubber compounds get gooey...some just get hard and glazed. Then some others harden and get these little bumps on them. They'll work, but it is a recipe for increased flutter. The original pinch roller on my 58 looked like that. If I were you, I'd get a new one. Now, Tascam said they didn't have them?? That stinks. I was able to get a new one for 234 and that is quite a bit older. Can you get the part number for it from them or did they give it to you? I could cross-reference. If you need to, send it to Terry (Terry's Rubber Rollers). You will get a better than new roller. You may pay a bit more than a new part from Teac, but if they are NLA then that isn't really an issue. Terry is a gauranteed service. I whole-heartedly support him.

Daniel et al, there are indeed only two heads, but on all the 8-track Teac cassette decks (238, 488, 688) it is a staggered head to increase the crosstalk performance.

Awesome. Thanks again. You guys all rule.

Although very rough around the edges, I really like the guitar/amp set-up I have. Hard to get it to break up except at uber high volumes, but then I can always settle for distortion/overdrive pedals. The reverb on that amp is fan-freakin-tastic.

I think the roller should be replaced, as I imagine the glossy area is more prone to slipping, but it has been more or less like that since I bought it, so I'm banking on the fact that my present issue has other primary causes (hopefully the belt). I appreciate the heads up about Terry's...

 

[heatmiser]

See, if it is something else, like the motor or something which regulates speed, that's gone south, then I think investing a little capital on the capstan belt (which I believe is the real major problem) would make sense first, to at least confirm that it is the capstan belt that's the issue. Then and only then, IMHO, should the focus be on restoring / replacing the pinch roller, idlers etc...

I ordered the belt from tascam tonight. Very reasonable. I upgraded shipping and it should be here early next week . I would've tried to tackle the roller at the same time, but that will have to wait for a bit. I guess one thing at a time for now. I'm just happy to have some direction here and some degree of hope!

I'd check and change the belt, for sure. While in there, I'd also make sure the pulley is properly affixed and tightened to the capstan motor shaft. A little slippage can cause a lot of grief.

Thanks for the tip Dave. I will take a good look around and try to check the pulley while I'm at it.

Yeah, heat. I'm sure you are gathering that we all think you ought to open it up and have a look at things...

Yes, the enthusiasm is palpable .

Just go slow, take pictures (both for being able to reassemble easier but also, selfishly, to see some pics of 688 guts up here...that would actually be great for other 688 owners if you have the time...totally understand if that doesn't work out tho'...), and when something isn't coming easy post up what's happening and I'm sure we can figure it out.

Will do. I will try to post pics and may take it apart this weekend. Maybe I should start a new thread for that process?

Anyway, I found the detailed thread I was thinking of:

https://homerecording.com/bbs/showthread.php?t=283800

It is just from last summer actually. Pretty step-by-step. Maybe I can just paste his instructions onto a new thread and add photos as I go...don't want to plagarize or anything though.

 

[heatmiser]

take it apart alreadY!

No seriously, I guess I'm up to it too real soon, since I own 3 of these and none has had a belt changed in almost 20 years. Same goes for the roller...They do still work perfectly though. Great machines!

Total Awesomeness!

I never tire of pix of casa cassette. I thought you only had two...now you are hoarding.

Yes, quite a lot of build up here. Almost certain to disappoint, but hopefully I will learn something (already have actually) and maybe help someone else along the way.

 

[cjacek]

I will try to post pics and may take it apart this weekend. Maybe I should start a new thread for that process?

Anyway, I found the detailed thread I was thinking of:

https://homerecording.com/bbs/showthread.php?t=283800

It is just from last summer actually. Pretty step-by-step. Maybe I can just paste his instructions onto a new thread and add photos as I go...don't want to plagarize or anything though.

A new "How to service your Tascam 688" thread might be an idea but if you decide to do that, I'd definitely link this thread to the new one to sort of continue the story, ala Cory's "Story..." related threads of time past.. Just my 2c..