Question about Inner Groove Distortion (especially on shorter records)

This is only given on a hotly cut record though. But yes, you need a thin profile to track most grooves perfectly.

 

I think it is related:

LP distortion mechanisms

Even if you have vertical tracing distortion, the pinch effect gives considerable distortion as shown in previous calculation. Tracing loss will reduce the level at high frequencies.

 

Thank you! A very good article.

 

Yes! The term "pinch effect" is the more accurate term vs "tracing distortion". Pinch effect describes exactly what happens as a conical/ mild elliptical stylus tracks the inner groove. This can occur at the outer groove, but so slight that we hear no distortion. The inner groove is where the groove pitch (angle) increases very sharply. Factors that determine groove pitch are how hot the record was cut, a very loud passage, frequency (increase of frequency increases groove pitch) and the linear speed of the groove relative to frequency. Pinch effect occurs almost entirely from a laterally cut groove, the mono component of a stereo record. The vertical parts of the stereo groove, or difference signal are seldom distorted at the inner groove. In other words, a mono record will produce lots of pinch effect distortion. (commonly referred as IGD, inner groove distortion) Pinch effect distortion does occur on a brand new record, any tracking force, any vertical tracking angle, any anti-skate setting... nothing gets rid of it.

It's not as much the size of the stylus, it's the shape. (given a not a worn stylus)

Pinch effect occurs when the stylus gets forced upward at the narrowed parts of a mono groove, or the mono component in a stereo groove. (sum signal) The upward motion of the stylus is not part of the audio signal, thus produces out of phase distortion artifacts. A mono cartridge mitigates much of the out of phase distortion electrically, although the conical/mild elliptical still does not track the groove properly. A high quality elliptical of say, 0.2 x 0.7 mils will track most reasonably cut records without IGD, but will be challenged by an extremely loud passage at the inner groove.

The only remedy for pinch effect is a premium stylus, such as a hyper-elliptical, shibata, line contact, or other linear contact type. The shibata in particular most resembles the cutting stylus, so it has negligible pinch effect distortion.

 

First question is if the Lps are used or new? Never had IGD apart from damage on used vinyl, even when I was less clued up on cartridge alignment. I would not trust factory settings and recheck everything myself. Get an alignment protractor and stylus balance.

 

Dynagroove was designed to make record playback better on typical phonographs. Unfortunately, it didn't even do that. It was a failure, and horrible for those who had good equipment or nicer. Conical styli for those records and other records cut with a tracing simulator computer is best, other examples are London/UK Decca Phase 4, and Telefunken/Decca Royal Sound Stereo discs. Dynagroove as RCA first envisioned it was mainly used in 1963, gone or highly retooled by sometime in 1964, audiophiles and music lovers hated it with a passion.

The Jico SAS and MicroRidge are the same type tip, brought to you by Namiki of Japan. Also note this type of stylus profile demands much more careful setup and optimization on overhang, on VTA/SRA for best performance. Easiest done on arms with easy adjustments for this. Likewise the same caveat applies for Shibatas, StereoHedrons, QuadraHedrons, Linear Contacts, Fritz Gyger, MicroLine, Van Den Hul, and other exotic tip shapes. They do give you more detail, often reduce inner groove distortion, and also better high frequency tracking ability, but also can give you a lot of artifacts you don't want on less than perfectly pressed records.

 

I'll be looking for some better carts in the near future. I've heard the AT44MLa a couple of times here, but at close to $500 on Amazon, that's definitely going to wait a good while since I JUST got my U-Turn Orbit with the Grado a few months ago.

I'll certainly save up for it if it's going to be reliable. But are there any other really good carts for IGD? I've also heard the AT33PTG/II; and the Denon DL-301II. Any other suggestions?

 

Audio Technica has replaced the AT440MLa/b with the VM540ML, so that's the one you'd want to consider in the AT line if you want a good microline cartridge. But it goes for around $250, so it's not super cheap (the AT440MLa originally sold for quite a bit less than $200 when it was in production).

Edit: LP Gear currently has the 440MLb for $236 (NOS at this point), but at that price, you're probably better off getting the VM540ML, which some people like more anyway.

 

AT95VL

 

Those prices are high because some joker is hoping people are really that dumb. The 440 may have been discontinued but it was replaced by the 540ML which is basically the same cartridge with some minor changes. You can buy a 540ML for $249.

AT also recently released the new VM95 series. There is a VM95ML (Microline) and a VM95SH (Shibata). You can buy those direct from AT for $169 and $199 respectively.

The AT33 and DL301 are low output moving coil cartridges. You'll need a step up transformer or MC head amp, or a very good MC capable phono pre to run those. Denon never says what the actual tip dimension are on the 301 styli. IIRC it's just a finely cut elliptical, not a true advanced stylus. The PTG has an ML stylus on a boron cantilever - that should deliver excellent tracking if properly set up on the right arm.

 

I'm using a VM540ML, I had a 440 and hated the tinny sound, the 540 is not the same!

 

But when everything is up to snuff, the rewards are greater than the disappointment.

 

Thanks for the tip on pressings to go for and ones to try and avoid.

 

I got the Audio Technica vm95ML cartridge last week. I’ve played about 25 records now and the only one giving me inner groove distortion is Toys In The Attic. The record sounds decent until the last track, You See Me Crying. This one sounds absolutely horrendous, everything distorts. Is this a known issue or my record simply damaged? I bought it used. I’m thinking that since I’ve had no problems on any other record, even ones with far more surface noise, that this is an isolated case.

 

Groove wear most likely.

 

If this is the most recent cut done by Ryan Smith (RKS) who does excellent cuttings, I’ll put my money on groove damage from the previous owner.

 

It’s an early pressing. I saw the recent RTI pressing at Wal Mart last week. I might pick it up to compare and contrast.

 

Reissue probably sounds better than the original anyway.

 

Low tip mass helps mitigate this. My Yamaha MC-1s with beryllium cantilever is pretty amazing in the inner groove, even on older/worn records.

 

I dont know of a relation between diamond mass and audible groove wear. What determines trackability of inner grooves is just the diamonds shape and how its installed.

 

This is a subject close to my heart, as I am running an AT95e on my LP120 that has given me nothing BUT IGD and pinch noise, no matter how heavy I track (I am at around 2.3 grams for this nominally two-gram cart) or how I play with the anti-skate (which I was told has nothing to do with it anyway)...

I can't afford the 440MLa/b replacement, by a long shot, but I had my eye on Turntable Needle's ATN3400 "HyperElliptical" stylus replacement/upgrade for the 95e for $120...does anyone have any personal feedback about this stylus? Should a HyperElliptical at least track the inner grooves better than the standard elliptical on the 95? I realize I'm not going to get shibata or microline level performance at this price, but does this 3400 seem like a good upgrade?

ATN3400 ATN95E Type HyperElliptical Upgrade Bonded Stylus for Audio Technica AT3400 AT95E etc 710-DHE

 

It is certainly a lot better than a normal elliptical. But if youre gonna spend 120$ why not go an extra 50$ and get the AT95ML which has a Microline stylus on it, which is the same as the 440MLa or more relevantly the current version 540ML.
This is pretty much the best stylus you can get for tracking, at least at this price. IGD should be near eliminated with proper installation.

heres from the same site:
AT-VM95ML Audio-Technica Cartridge | Turntable Needles

 

If yo

If you got those Aerosmith LP's used, I'm betting they got a beating on some head bangers old TT. So could just be groove damage from an old beat up cart.
I have a couple of their newer re-issues. Was hoping for the sound of the original LPs I loved so much but turned out to be disappointing.

 

Might be a hair better but $120 for a bonded "hyperelliptical" vs. a nude microline at $169 is penny wise, pound foolish.

 

You should try the new VM95en if the ML is out of your budget. I bet it is a big improvement going to the nude stylus(it was for me 100E to nude 120e). Then you could spring for the ML stylus later on.