Thump noise on the lead in on warped LPs


Hello friends
I have a Mitchell Tecodeck, with a upgraded Garrot Bros P77 cartridge.
I have moved appartments, which means I can turn up the volume a bit, but not that much!!
I have had a bit of a promble, a lot of my mint LP,s were purchased with shwink plastic, and a lot comes with a slight warp(Which I guess is normal)
I have played all above with no prombles, but now seem to have a "Thump" on the lead in track, when the cartridge,arrive to the top, but when the cartridge drops down from a very slight warp, it makes a Thump??, untill, half way thought 1st track, where it settles down
Hopimg some can help
Regards
David
128x128daveyonthecoast
I would try to fix the warp.

There used to be devices to fix warps. One remedy used to be to gently heat the vinyl between two sheets of glass in an oven. (Done carefully!)

I have a ring clamp on my VPI turntable which is heavy enough to flatten most warps.

Question: If this thump did not occur before your move, what has changed? Did you change any of your tonearm settings, like stylus pressure? Is the turntable support still level?
I suggest the back of your cartridge is hitting the vinyl .....a ring clamp would add height to the edge and probably make it worse. I suggest you raise the back end of your arm.... the result might even be better sound.
Turntables are tricky things to get set up optimally.

Warped records are always a problem, but more so with some setups than others.

Others might correct me, but if you hear the thump noise frequently regularly even with just modestly warping in the records, I'd suspect initially its most likely some combination of the tonearm having trouble tracking the record through the warp combined with a table system resonance occurring in the frequency range where the thump noise occurs.

All tables have resonant frequencies, but they can be tweaked in various ways using different combinations of tonearms of various mass and associated carts. There is info in agon forums and other sources on how to address these things.

Also, in general, higher mass tonearm/cart combos tend to have more difficulty in general trqacking through warped records due to the higher mass and associated inertia.

Its hard to recommend a specific solution to this problem, but at least these are the things I would say are worth researching and giving some consideration to to help remedy the problem.