Onkyo TA-6511 problems with sound...

The belt has arrived.

Any idea what this could be on the flywheel?


There are 3 pairs of those marks, 120° apart (the Y).

It looks like it would rub off with a finger (if I would rub for a looong time).

Flywheel is made out of plastic, can I clean it with IPA?

Currently I'm cleaning it with soapy water, but I'm getting nowhere...
 

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A plastic flywheel is something I've never seen. Plastic coated maybe? Usually you need the weight and mass of a heavy flywheel to smooth out wow and flutter. Iso should be safe on plastic. I can't really make out the marks in the image to get a sense of what they are :)
 
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Hy, I'm not liking the plastic flywheel either, maybee it's just coated, I don't know, but it feels alot lighter than the one on my old Akai.

But guess what ... New belt thankfully fixed the issue with "robotic voice".
I will have to do further recording / listening to make sure everything else is good...
What I recorded with Akai still plays slower on Onkyo, but maybee the Akai is spinning too fast, will have to set up old Alpine car radio (the one that I fully trust), to see if either Akai is too fast or Onkyo is too slow...

Originaly I bought the Onkyo to record tapes for the Alpine, that I will use in my oldie when I put it on the road...
But as cassettes were a part of my childhood, I got sinked in and now Onkyo has a place in the living room :)
 
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That's great that the belt has fixed it... I wasn't hopeful on that tbh but good to hear its OK now (y)

If the speed is a long way out then you really need some kind of reference to begin with. Maybe a prerecorded tape with something that you can hear online as well as a speed comparison. I seem to recall many C90's playing for around 47 minutes per side and C60's playing for around 31.5 minutes give or take. Even something like that would get you to within a couple of percent.
 
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Prerecorded yes.... I had just remembered that I have old Dirty dancing prerecorded cassette and yes, it's playing too slow.

"The time of my life should be at 109BMP"...
By ear I would say it plays at 95-100BPM....
I will get Virtual Dj running and beatmach to the deck to see where it is...
 
Now that was a painfull thing to do after a loong time not doing it... but I manage to do it.
It's playing at 95.5BMP instead of 109.

I guess that right process would be to buy 3khz (or some different frequency) test tape, get line in on pc and some kind of software to show me the played frequency and match the speed?

But for now I would like to set it with a song... I guess if 5 minute long song plays perfectly start to finish, it should be pretty close.

The belt I installed was made by Thakker.
I can't imagine why speed would be off...
Should I jump straight into adjusting speed on the motor or should I check anything else like supply voltages for example first?
 
It's playing at 95.5BMP instead of 109.
What is BMP?
I guess that right process would be to buy 3khz (or some different frequency) test tape, get line in on pc and some kind of software to show me the played frequency and match the speed?
Either buy a tape sold as "test tape" e.g. from eBay or ask any friend with and adjusted deck (some of these are quartz-locked) to record one for you.
For hobby purposes you do not need a factory level tape.
 
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I would be surprised if the supply to the motor was low but measure it by all means. It would have to way down to affect motor with inbuilt speed control though... so very unlikely. I would just give it a tweak and see how it responds

Remember tape decks like this had only average speed accuracy and if you get it to within 1% then that would considered acceptable. If your other deck is considered OK then use that as a reference and match this one to it.
 
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BPM is beats per minute, used to measure music speed in production & DJing, for example trance music is at about 133BPM -kick hits 133 times in a minute.

Power supply voltage is good. I adjusted the speed and I'm pleased with the result.
Will order test tape.
 
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