What do you think causes the crackle and clicks we hear?

Actually, groove wear does not cause pops or ticks. It slows groove velocity. Dust ground into the surface does that along with static and overload. This is a problem we have all learned to live with. It just goes with the territory. If you don't like it go digital. 
MC you really need to go digital. This stuff is getting to your head or whatever you call it:)

I think pops are easier to understand but clicks and crackle noises, what causes this?

Some of course are caused by damage to the LP surface and static electricity. But not all. Many ticks and pops are caused by radio frequency overload of the phono section. The RFI is caused by the operation of the cartridge, which has inductance, interacting with the capacitance of the tonearm interconnect cable.


Many phono sections simply are not designed to deal with the RFI generated in this manner! So they overload and you get a lot of ticks and pops. When I say 'many' I mean most.

would disagree on static discharges, and some of the other ideas.

Have looked into this for a long time and taken many microphotographs of LP / vinyl groove surfaces.

first you need to understand what is  mixed in with vinyl pellets before the record pressing plants ever sees them. Many think mold releases are used. Have not found that to be the case.

But during PVC pellet processing, Calcium carbonate is added to almost all vinyl formulas during formulation as a processing aid for all the manufacturing steps, from extrusion, to pelletizing to molding.

during the record pressing cycle, the calcium carbonate is still in suspension in the PVC vinyl matrix during the heating cycle. During the cooling cycle, the rapid change in temperature causes the Calcium carbonate to migrate to the the cooler surface, collecting in the bottom of every groove.

As the stylus tracks the groove, the bottom of the stylus is hitting the tops of these larger particles. Want evidence? Take a look at the bottom side of your cartridge. you will likely see some fine dark white to light tan tiny particles clinging everywhere. these are tiny calcium carbonate particles the stylus removed from the bottom of the groove.

Have looked at over 300  records under a microscope and have never found one without the deposits.

Removing the calcium carbonate is the key to removing ticks and pops, and general groove noise. and its tough to do. But one done, its amazing how much better your vinyl will sound.

it can be removed with an ultrasonic machine as well as a vacuum type machine (VPI or nitty gritty).

Both require numerous passes on each side to remove the particles.

But once removed, your records will get amazingly quiet and the resolution and imaging will improve much more than swapping in a new phono cart.

best









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Interesting, John. Thanks for sharing!

Johnss, I have looked at many new records under a binocular microscope and have seen no such residue. The occasional finger print, some dust but no calcium carbonate. You see these round crystals in horse urine. I look for calcium pyruvate crystals in human joint fluid all the time differentiating pseudo gout from gout ( uric acid crystal arthropathy)
Uric acid crystals being negatively birefringent needles versus thepositively birefringent rhomboids of calcium pyruvate. 
The mold release agent is a very small part of the PVC additive mix. Additives such as plasticizer, the mold release agent, carbon black and some other stuff make up 2.5% of record PVC mix. It is in the mix. Not on the surface. 
Contrary to popular mythology generated by the record cleaning industry new records do not require any special cleaning as long as static is neutralized and incidental dust is swept out of the way. Only poorly kept used records require cleaning. I personally do not buy used records. I can certainly understand using a record cleaning machine on them though. But instead of all that record cleaning stuff I would rather spend the money on new records. My perspective may be different as I have been collecting records for over 50 years and have a fine stash of vintage records.