Yamaha MT4X Pitch Lowers As Tape Is Playing

Rick N. Backer

New member
Hi all,
I hope I'm posting this in the correct forum. If not, my apologies! I'm brand new here.

I guess the title says it all. I pop my tape in and as it's playing the pitch gets lower and lower. Never faster, just lower. [My MT8X is the opposite and only plays faster, but I may make a separate post about that.]

From what I'm reading about my MT4X it could be a problem with the belts being stretched out.

Could there be any other reason why this is happening?

If it is the belts, where would I buy new ones?

Thanks everyone!
 
I have no idea for sure without having the machine in front of me. But one thing I DO know for sure is the rubber parts fail. They either dry up and become slick or harden or turn to goo. It is inevitable. And 95% or better of all issues with vintage cassette machines are resolved by replacing the rubber parts with new parts and lubricating moving mechanisms of the transport.
 
I have no idea for sure without having the machine in front of me. But one thing I DO know for sure is the rubber parts fail. They either dry up and become slick or harden or turn to goo. It is inevitable. And 95% or better of all issues with vintage cassette machines are resolved by replacing the rubber parts with new parts and lubricating moving mechanisms of the transport.
Thank you. I will replace all the rubber parts. Is there a store you know of besides eBay? And what kind and brand of lubricant do you use? I figure I'm here to learn from the best, so I might as well ask. :)

I'll keep looking around for all the parts and I will definitely do everything you said.

Thanks again!
 
I know of no “store” that sells these parts. Back in the day you ordered them from the manufacturer. You can always contact Yamaha parts to see if they still have the parts but you may need to find the service manual to verify what kinds of rubber parts are present on each machine. Some have control belts…some do not. Sometimes there’s one, sometimes there’s two. Sometimes there’s a capstan belt, sometimes not. There’s always, on a cassette machine, at least one pinch roller. Sometimes there is a counter belt. If the counter is digital usually there is no counter belt. If the literature refers to a “direct-drive” capstan, there is no capstan belt. Usually there are one or more reel table drive “tires”. The Yamaha machines are less popular…not as many made. This doesn’t mean there not as good. They are good machines, it’s just harder to find parts and community support for them. I’ve never owned one or had one in front of me. You can just do a web search for the parts once you find what’s on the machine. It doesn’t have to be eBay, but that’s often times where I purchase rubber parts. Athan Corp makes the best replacement pinch rollers. I don’t know if they have the Yamaha parts.
 
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I know of no “store” that sells these parts. Back in the day you ordered them from the manufacturer. You can always contact Yamaha parts to see if they still have the parts but you may need to find the service manual to verify what kinds of rubber parts are present on each machine. Some have control belts…some do not. Sometimes there’s one, sometimes there’s two. Sometimes there’s a capstan belt, sometimes not. There’s always, on a cassette machine, at least one pinch roller. Sometimes there is a counter belt. If the counter is digital usually there is no counter belt. If the literature refers to a “direct-drive” capstan, there is no capstan belt. Usually there are one or more reel table drive “tires”. The Yamaha machines are less popular…not as many made. This doesn’t mean there not as good. They are good machines, it’s just harder to find parts and community support for them. I’ve never owned one or had one in front of me. You can just do a web search for the parts once you find what’s on the machine. It doesn’t have to be eBay, but that’s often times where I purchase rubber parts. Athan Corp makes the best replacement pinch rollers. I don’t know if they have the Yamaha parts.

Thanks again, sweetbeats!

Sorry, I didn't mean a store, I meant any place online where you can get replacement parts. I thought maybe you or someone knew of a place you buy from specifically.

*** And please don't pay any attention to my asking about "online stores" in my MT8X thread. *** I didn't see your reply here until after I replied in that thread.

Jeez, how many belts do these things have?! So far I found "Replacement Kits" on Reverb for my MT4X & MT8X. They consist of 2 belts and a pinch roller for my MT8X and same for my MT4X plus an "Idler Tire" (4 belts total if you count the Idler Tire as a belt). Like I said in my other thread, I may be able to ask the guy to make an Idler Tire - I hope I'm saying that correctly. Obviously, these terms and the inner-workings of multitracks are still new to me. I've only messed around with 1 or 2 others and I actually got one to work. I'm pretty handy and I have plenty of patience when working on them. I'm just very impatient when waiting to get paid Friday so I can order the belts and roller! Lol

I'm doing like you said and just replacing all the rubber parts.

It's too bad some of these belts can't fit other models. Instead of worrying about the Idler Tire belt specifically for the MT8X, it'd be cool if I could buy a different one for a different model and have it fit mine. Oh well. Maybe I'll ask the guy on Reverb. He makes custom belts which is pretty amazing.

Thanks again!!!
 
Don’t call it an idler tire belt. A belt is a belt. A tire is a tire.

And sometimes you can find common parts between models, but it takes investigative work, and sometimes even the expense of buying something you think may have common parts you need at the risk of finding out it doesn’t work. I’ve had to do stuff like that with my Audio Technica AT-RMX64…no service manual available and no parts support from AT at all…more rare machine with little community support…you have to use reasonable deduction practices and other clues. But I was able to find a Nakamichi deck with the same idler tire, and that’s how I replaced the idler tire on mine with a new part.

See my other reply in the MT8X thread.
 
My mt1x has a lot of pitch fluctuations but I always have found it apart of the cassette tape experience. How drastic is it?


I’ve replaced most parts on my mt8x, but you just have to do a bit of research, as to the dimensions and what not

Fixyouraudio.com has a bunch of pinch rollers that I’ve used for various cassette machines, also Amazon has a lot of belts. Speciality places like westcoastbelts also have some more specific stuff
 
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