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Why are records still warped?

This is more of a grouse than anything because I know the molding process won't ever be perfect. Still, here we are in the 21st century in the midst of a vinyl revival. Artists get it and are trying to satisfy us geeks with tasty pressings.

Cases in point are Bennett & Gaga's "Cheek to Cheek" and Lennox' "Nostalgia." Ordered both of them in (live in the sticks so no local source) and one dished, the other warped. Neither are unplayable, but both conditions are audible. Disappointing to say the least on such outstanding efforts.

The same week they arrived, I got copies of Hampton's "Silver Vibes" (mono) and Mendes' "Look Around" used at a swap meet. Perfectly flat with outstanding fidelity, especially considering their age.

Many of my "not" Golden-era pressings from the mid-70s through late-80s also lived up to expectations when I got them home. Many more did not, and that's why I ended up jumping on the CD bandwagon with a Sony CDP-101 in 1983.

In 2015, my digital playback deck is about 1000% better, CDs are better, SACDs are even better still, HD downloads can be superb, but still none of them best vinyl at its best. Unless it's warped.

We have the technology, know better and can better control the process. So, what is up with the warp thing? Is it laziness, budget or what?!?
effischer
lowrider57's avatar
lowrider57
5,417 posts
 
I've also been told that venders have to pay for the cost of a return in this new vinyl world. I'll bet a company with the "buying power" of Amazon doesn't eat these costs and returns them to their distributor.

In the good old vinyl days, you would return an LP to a store and usually get an apology. Then the owner/employee would inspect another copy to make sure it didn't have the same defect.
Oh, the good old days.
wattsperchannel
142 posts
 
If you really want to know:

An inherent outgrowth of the polymerization process is that each individual polymer chain has a different molecular weight (chain length). When the PVC pucks are formed (before the record stamping) they are created from small plastic pellets which are melted with heat to form the disk.

When the plastic melts it expands. When the plastic re-solidifies it shrinks an-isotropiclally (different amounts in different directions) due to the viscosity variations caused by the molecular weight (polymer chain legth) differences. This variation in shrink by direction causes warp. Some of the warp occurs initially but some will occur over time as the record sees elevated temperatures that cause the internal stresses (caused by the variation in shrink in different directions) to relieve themselves.

Even though the record business is run on antiquated equipment, all of the above challenges are faced by the highest precision plastics companies in the world. While improvements could be made through more modern equipment, longer cycle times, etc., no one will ever be able to make a perfectly flat record that stays flat it's entire life until constant molecular weights are achieved in the initial polymerization process.
swampwalker's avatar
swampwalker
5,138 posts
 
WPC- Thanks for the information which explains this issue very well.
effischer OP
564 posts
 
OP here - + 1 to WPC. A thorough and exact explanation of why it still happens with such alarming regularity. Thank you.

Also, I appreciate Lowrider's input. I knew there also had to be a business philosophy behind the bad attitude. Losing money sure makes folks cranky.
actusreus
733 posts
 
Perhaps I'm missing something, but I own many, many a flat record, some decades' old. Unless the polymerization process is a brand new phenomenon, which it shouldn't be, the thread question still stands and WPC's explanation is an interesting piece of information, but not much more than that. I think Bdp24 hit the nail on the head 2 months ago.
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