kaplang
Works for me !
Maybe or maybe not, It’s sometimes hard to tell.
Drop the needle: platter moving or not?
- Thread starter hbucker
- Start date
gusten
Addicted Member
So it gets harder at 33.3 rpm?
45 and 78 rpm records must get even harder
The needle sees the vinyl as harder when high velocity difference, there is not enough time to build up needed forces for indentations. That is why vinyl works as a format.
So it gets harder at 33.3 rpm?
45 and 78 rpm records must get even harder
My lady plays all of our records at 78 heh heh heh.
I think there's some confusion between motor load and the friction between the needle and vinyl. The car metaphor (starting from a stop vs. maintaining speed) doesn't apply to the question at all.
Although I know virtually nothing about the topic, my brain tells me that the force\drag that the needle sees will be the same no matter if dropped with platter is moving or not - it's just the rate of speed in which the force is accumulated (as seen by the needle).
Or did I miss something here?
Although I know virtually nothing about the topic, my brain tells me that the force\drag that the needle sees will be the same no matter if dropped with platter is moving or not - it's just the rate of speed in which the force is accumulated (as seen by the needle).
Or did I miss something here?
Needle sitting will be more inclined to dig into the vinyl. Lots of PSI at the tip of that thing. Tracking force might only be a couple grams, but the contact area is extremely small. Its definitely enough to press the tip into the vinyl, which just isn't that hard a material. Keep it moving and it won't do that.
Moral of the story, if you sit the stylus on the vinyl when it is not turning, the stylus can dig itself a little hole that you're then moving when the motor switches on. It could be possible to rip the diamond off the end. Maybe it won't happen but there really isn't any reason to risk it.
Moral of the story, if you sit the stylus on the vinyl when it is not turning, the stylus can dig itself a little hole that you're then moving when the motor switches on. It could be possible to rip the diamond off the end. Maybe it won't happen but there really isn't any reason to risk it.
beatcomber
AK Member
So, you are saying the contact area changes based on if the platter is turning or not? I'm just trying to understand, as I said, I know virtually nothing about this topic.
Or that the acceleration from a dead stop would apply the force more gradually than needle drop on moving platter? Man, I'm corn-fused. I better stop now, LOL
hbucker
Well-Known Member
I'm hearing him say, and the concept makes sense to me, that the spinning record displaces the force of the stylus across a wider area. Therefore, the load of the stylus is much less likely to damage one specific point on the disk.
I'm seeing it like this:
You're standing at the edge of a frozen pond. You are required to cross it, but you're not sure how thick the ice is. Would you be more likely to take a run at it and slide across the ice to the other side? Or would you prefer to go slowly, standing in one spot to make sure the ice were strong enough to hold you?
I would take a run at it, not wanting to stop in one spot too long.
That's the concept I'm hearing with moving platter vs stationary.
I do hear all kinds of talk about how vinyl is so fragile and easily damaged. Everything from "vinyl rot" to unlistenable damage caused by lower quality needles. Yet my 40 year-old records still sound good after being played on a variety of different turntables (the worst being my parent's old Magnavox console). So, I think vinyl is more durable than many give it credit for. Still, the above idea makes sense to me.
Right, it doesn't alter the contact area, it just doesn't have a chance to sit in one static location and potentially deform the material. The vinyl will "creep" away from the pressure point, allowing the stylus to move inward. If you keep the parts moving relative to one another there isn't enough time for the vinyl to move away from the stylus.
We're talking very tiny amounts here, but its a very tiny part. I don't really know if ripping stylus tips off is a major concern but its not impossible. The vinyl will mostly re-form back to it's original shape if you do this, its the stylus itself that I'd be more worried about, particularly the really small ones on super low mass (aka expensive) cartridges. I doubt you could affect a console changer or a modestly priced moving magnet cartridge if you tried. Would I try that with a several thousand dollar moving coil unit? Not a chance.
Records are tougher than people believe, and largely because they are not hard. "toughness" and "hardness" are almost inversely proportional. make stuff too hard and it just shatters. Throw an LP on the sidewalk and do the same with a shellac 78 sometime. One will shatter, the other just scratches.
We're talking very tiny amounts here, but its a very tiny part. I don't really know if ripping stylus tips off is a major concern but its not impossible. The vinyl will mostly re-form back to it's original shape if you do this, its the stylus itself that I'd be more worried about, particularly the really small ones on super low mass (aka expensive) cartridges. I doubt you could affect a console changer or a modestly priced moving magnet cartridge if you tried. Would I try that with a several thousand dollar moving coil unit? Not a chance.
Records are tougher than people believe, and largely because they are not hard. "toughness" and "hardness" are almost inversely proportional. make stuff too hard and it just shatters. Throw an LP on the sidewalk and do the same with a shellac 78 sometime. One will shatter, the other just scratches.
This is down to level at which my brain works - this I do understand - spreading that drop force over a wider area. Well done, and thanks.
Thanks to you to Gadget for taking the time.
vwestlife
Super Member
Ask any old-time radio DJ. Starting the platter with the stylus already in the groove causes cue burn, especially on styrene 45s.
http://tenwatts.blogspot.com/2007/12/cue-burn.html
http://tenwatts.blogspot.com/2007/12/cue-burn.html
