Maybe, but probably not very practical. How long before successful alignment each time you play a record? With a pencil line it's permanent...throw it on and push it in place.
Can you describe the procedure with your spindle and then with the added pencil line? I'm seriously intrigued.
Just describe how the adjustable spindle works. What TT is it? I'll check it out on line.
Good to know. The early Sure test record from the early 70's was self defeating in that it also was off center and was useless unless you centered it first.
How so? The instruments of the day were not capable of the narrow BW detection needed to actually see the difference. Any fixed frequency has to average over a 1.8sec period (.5556Hz).
It's a roksan xerxes. Attached pic is best I could find in a rush to show how it looks with the outer spindle removed.
Attachments
A Rube Goldberg machine is one which makes simple tasks in the most complicated and indirect way possible ... instead of straight addressing the original problem.
How would YOU address the original problem? (and give up on vinyl is NOT an acceptable answer) 🙂
I was referring to the one used for minimizing tracking error of a cartridge. It consisted of a series of progressively difficult tracks for a stylus to follow plus tracks for accurately setting AS and VTA.
I don't see where "adjustability" comes into play. The idea is to remove the spindle after centering the record on the platter. So I understand your previous statement where you said you could also use a pencil. I was imagining an off center spindle which you would rotate, moving the record til it was concentric. 😉
I already answered on post #12 😀
😎
In case it´s not clear: drill a new hole in the proper center 🙂
You put the record on at the nominal centre (if it were made correctly). You then pull the outer spindle off and have all the adjustability you need. I did look at an off centre spindle, but it's hard to get the accuracy unless you machine 50 of them and a nudge to align with a pencil mark is very quick and easy.
Does not reference the hole at all:
YouTube
Yes, the form with onboard speaker has huge wow from Doppler, unless you listen from directly over the center of the orbit. And bass and stereo are compromised. But picture a radio link; better, a clocked data stream buffered to another stable clock in the receiver.
Another, this one "wireless":
YouTube
YouTube
Yes, the form with onboard speaker has huge wow from Doppler, unless you listen from directly over the center of the orbit. And bass and stereo are compromised. But picture a radio link; better, a clocked data stream buffered to another stable clock in the receiver.
Another, this one "wireless":
YouTube
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I don't like that solution in the OP, because there's still the tracking error that goes one way then the other with each revolution of the record, perhaps accentuated by the dynamic movement of the tonearm being pushed back and forth.
Fixing ths is one of the big features of my "ultimate TT design/build" that I will likely never get around to. It works pretty much like the Nakamichi (or how I imagine it works).
Have the spindle be movable inside the platter. Use two hobby servos (SG90 should work fine here), placed at 90 degrees from each other relative to the platter center. Each servo's horn (mechanical output) is mechanically connected to the spindle, so that it moves it maybe 1/4" in each direction (if the record is further off than that (!), just take the spindle out and align the record manually).
Connections to the servos in the rotating turntable can be made via concentric conducting circles on the bottom of the platter, with a mechanism activated by a third servo (or maybe just solenoid) that pushes conducting brushes up against the circles while the adjustment is being made. There would be no mechanical/electrical connection while actually playing and listening to a record.
This leaves the problem of how to detect eccentricity and generating the corrections to send to the servos. A device detecting tonearm angle, as used in the first video (or in the Nakamichi TX1000 video), could be used.
Or, with modern digital electronics and "A Simple Matter of Programming" (TM), one could use a Raspberry Pi and a camera made for it to look at, for one thing, the lead-in groove (looking for constant velocity movement as the record turns) and tell how far off the center of the pressing is, and send appropriate signals to the servos to correct it. I like this because you're not wearing the stylus on the record while centering it (doing something other than listening to the record content).
Fixing ths is one of the big features of my "ultimate TT design/build" that I will likely never get around to. It works pretty much like the Nakamichi (or how I imagine it works).
Have the spindle be movable inside the platter. Use two hobby servos (SG90 should work fine here), placed at 90 degrees from each other relative to the platter center. Each servo's horn (mechanical output) is mechanically connected to the spindle, so that it moves it maybe 1/4" in each direction (if the record is further off than that (!), just take the spindle out and align the record manually).
Connections to the servos in the rotating turntable can be made via concentric conducting circles on the bottom of the platter, with a mechanism activated by a third servo (or maybe just solenoid) that pushes conducting brushes up against the circles while the adjustment is being made. There would be no mechanical/electrical connection while actually playing and listening to a record.
This leaves the problem of how to detect eccentricity and generating the corrections to send to the servos. A device detecting tonearm angle, as used in the first video (or in the Nakamichi TX1000 video), could be used.
Or, with modern digital electronics and "A Simple Matter of Programming" (TM), one could use a Raspberry Pi and a camera made for it to look at, for one thing, the lead-in groove (looking for constant velocity movement as the record turns) and tell how far off the center of the pressing is, and send appropriate signals to the servos to correct it. I like this because you're not wearing the stylus on the record while centering it (doing something other than listening to the record content).
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