Tracking down cause of distortion on vinyl


Hi all -

Recently LPs on my modest system (Technics SL-1200 w/ KAB Groovemaster) have been sounding off - kind of thin and distorted, especially on loud tracks or passages. The stylus on my cart was destroyed by someone in the house, and I had to replace it with a JICO back in February. The JICO was fine at first (although the suspension was not as good as the original - did not track as well and needed higher force), but I have heard they have quality control issues and suspect that is the cause. But how can I actually verify this?

Is it worth getting a test LP (I hear mixed opinions on the worth of these) - is there anything typically there that would isolate mistracking, say, as the cause?

I love the cartridge, but don't love the idea of ponying up for another questionable stylus (assuming I'm unlikely to get any credit on it now), if that is indeed the problem.

Also, is it true that if it is mistracking badly it is damaging any vinyl I put on?
dmsantini
For $50 at least get yourself an AT30 and see if the problem is the replacement stylus or otherwise.
"with the JICO, records were much more likely to skip from anyone walking around the room, lead-groove skip became common, etc."

That's the key sentence. The compliance of the new assembly is different than the original. It's like putting the wrong shocks on a car. Read on...

http://www.theanalogdept.com/cartridge___arm_matching.htm
http://www.vinylengine.com/cartridge_database.php
http://www.soundfountain.com/amb/ttcartridge.html

Setting up a phono cartridge can be a pain in the butt, but must be taken seriously and done properly. If you decide to purchase a new cartridge, make sure it will match well with your arm. Hopefully, you know the overhang spec and have a way to measure it.
Hi Richard,

You obviously know way, way more about this stuff than I do. The KAB Groovemaster was one of Stanton's DJ carts, fitted by Kevin @ KAB with a stylus along the lines of a Pickering D3000. That stylus was destroyed by someone accidentally (I went to play a record one day, and it was bent completely sideways).

The JICO imitation stylus sounded perfectly good for the first few months, so I don't think the diamond was off-alignment in the beginning. However, there were immediate differences from the original - with the JICO, records were much more likely to skip from anyone walking around the room, lead-groove skip became common, etc.

I suppose it's possible that whatever inferior material they used has caused the suspension to sag, changing the VTA of the diamond. I did mess with adjusting that some, and it did seem to help a little bit, but just a little.

Right now I'm playing with a Grado Gold I got from someone on here, trying to get that aligned perfectly. First attempt was not great, second attempt pretty good, but I think there's still room for improvement. But I fear that whatever mistracking the old cart was doing did do some damage to some records (comparing a few that I know I listened to and heard distortion with the old cartridge to records that I did not play at all during that period), so I'm loath to do much more testing with that needle.
"Groovemaster:" that sounds like a disco cartridge from the Florida incarnation of Stanton, right? (Sorry: I need corroboration because, although I wrote a book about Stanton/Pickering products, I haven't covered them after they went disco because their own product information has been so dodgy and unreliable).

What are the specifications of your original stylus? I know that Jico isn't in the habit of stating certain specs (I disapprove of any needle seller who doesn't give them up-front, by the way).

First, Stanton's products, even in the Florida incarnation, have offered that superb blend between performance and toughness that's always been their specialty. The ruggedness is focused in the stylus assembly. To break a Stanton needle takes a bit of doing. Yet, it can happen. A curious cat can do it. It's unlikely that your original Stanton stylus could "settle in" to the degree that its vertical tracking angle has changed. And I understand that Mr. Bacon likes to personally inspect the Stanton needles.

Imitation needles, however, don't duplicate every feature of the original, even if the patents have expired. They especially don't match Stanton's ruggedness. A dealer once sent me three imitations for my opinion. Two of them were originally good, but their elastomers hardened over time. Thus, five years later, they have the compliance of a wood toothpick and even with increased pressure, they sound awful. Cause: the imitator made a poor choice of rubber for the elastomers.

Stanton's stylus design, although the industry's strongest, isn't engineered with rotational alignment "locking" shapes (The ELAC/Shure's square mounting tube does). Thus, it's possible for a factory final assembler to either get the rotion wrong or to fail to "worry" the rubber elastomer properly so that tension doesn't cause the rubber to settle into an incorrect position. In short, examine your needle, viewing it from the end, and see if the diamond is rotated out of the correct position. If I remember correctly, factory tolerance should be within 5 degrees.

Some imitation needles, especially those that don't track very light or have advanced diamond shapes, can perform well. But they can differ from the orginals, slightly, in vertical tracking angle/stylus rake angle.

So, what I recommend is that you experiment with fore-aft angle of the cartridge. Excessive VTA, even if by only a couple of degrees, can cause the sound to be harsh, especially on the sibilants and other complex waveforms.

I'm interested in knowing if this works for you.

Richard
This is an integrated cart, so there's nothing to adjust relative to the tonearm - if it's misaligned, presumably something is damaged with the cantilever.

I have actually cleaned it with the Magic Eraser since this started (I'm a little scared of that device, so try not to use it much) and use a Zerodust before every LP. (Interestingly, Kevin/KAB is not a believer in either of those accessories.) Of course it's possible I'm not using the Magic Eraser effectively - I'll try again with the audio on so I can hear that it's doing something.

However I have noticed that the new JICO stylus seems more likely to pick up dirt by the end of playing a side than the old stylus did.

Long ago there was a stereo store here in the DC Metro area which would put your cart under a high-powered microscope and check it out for you - too bad they're not around, as I would like to have it inspected.

The guesswork aspect of all this is troublesome, unless I just feel trying another cartridge out for fun.

I will definitely avoid playing favorite vinyl while I work this out. Thanks for the responses!
A dirty stylus can sound a lot like you described. Before you spend significant money on a fix which might be only guesswork, try properly cleaning your stylus.

The key word in the previous sentence was, "properly". I've saved a dozen "worn out" or "damaged" cartridges (including very expensive LOMC's that cost more than your whole rig) for owners who swore their styli were clean before sending them in for service/replacement.

They were wrong but happy to be proved so, since I saved them thousand$ in unnecessary replacement costs. Here's how: Effective stylus cleaning. Search for "magic eraser" on this forum or Vinyl Asylum for hundreds of user testimonials.

Doug

P.S. Regarding a test LP, you've already used several. The records that your stylus isn't playing/tracking cleanly demonstrate clearly that there's a problem. No test LP will tell you any more. It's excellent that you're using your ears and real music to identify and try and diagnose problems. I own several test LP's and can't remember the last time I actually used one, despite setting up dozens (hundreds?) of cartridges. All my setups, tweaks and diagnoses are done using real music.

P.P.S. Yes, if your stylus is mistracking you may indeed be damaging your vinyl. Such damage is permanent and cannot be repaired. I'd advise against playing any important or valuable LP's before you find and fix the problem.
If the replacement cantilever's compliance is weak/out of spec, causing the relationship between the signal generating components(magnets/coils) of the cartridge to be out of alignment; you will experience the lack of fidelity you describe. Increasing or decreasing tracking force, from that recommended, will have the same effect. Bite the bullet, and buy a new cartridge, or an OEM stylus. KAB warns that the cantilever is especially vunerable to damage on this cart, being, "nude". You may want to factor that into your decision(weigh the risks in your environment). BTW: KAB has a Stanton stylus listed, that was removed from a brand new Groovemaster V3, for $20.00( http://www.kabusa.com/frameset.htm?/stantondj.htm )
You must 1st make sure that the cartridge is properly mounted to the tonearm. If it still sounds off, have the stylus inspected under a microscope to make sure it is in good condition and not dirty.

Finally, *yes* you can damage your records by dragging a poorly aligned stylus thru those grooves. If it's way off, one playing could ruin the record...

-RW-