Cartridge and tonearm advice - diagnosing IGD issues

[rbphoto]

If both LPs have this distortion, it may be in the master. Can you get this similar distortion with any other albums from another artist?

It absolutely may be, part of the challenge here is that I’m not experienced enough with vinyl playback to know what audible artifact is caused by what fault, be it setup, equipment condition, pressing, mastering. I’m learning quickly though!

So when I describe the clipping noise as IGD, I could well be wrong - my understanding is that it usually relates to intermodulation distortion in high frequency caused by the stylus not able to track properly at the lower rotational speed towards the runout, and that’s not the same as an amplitude-related clipping which is what I hear towards the runouts on Endtroducing, which says to me it may have been cut into the lacquer somehow. And that just baffles me. Abbey road?! Seriously? I know there are other possibilities, I want it to be the pressing plant or the deck or me. FWIW the rest of the record sounds fantastic, the consensus on discogs is this is now the definitive cut of this release.

The artifacts I’m hearing on other discs I now realise are probably the result of off-centre pressing, namely a background tearing sound every revolution as the tonearm tries to track the eccentricity. I simply didn’t know to look for that, now I’m seeing it on at least half the titles I’ve bought, to some degree. I don’t know if some arm/cartridge combos make this more or less audible, but I’m sure they do.

Then there’s the pumping/rumble, which is probably there on every second new record to some degree.

So I think the conclusion is the deck is set up as best it can be, and everything else is a product of inherent or introduced issues in the media or environmental factors.

Coming from a machining mindset this is all super fascinating, it’s like trying to hold really tight tolerances on a complex part that is cast, so there’s inherent stresses in it before you even touch it, and then there is tool wear , clamping distortion and thermal expansion to compensate for… I watched Michael Fremer’s tour of Acoustic Precision last night, what a trip. I couldn’t help but laugh at the idea of using these exquisitely engineered precision instruments to extract musical pleasure from your average contemporary commercial vinyl release.

 

[rbphoto]

Back to the actual diagnostic stuff, I have a feeling I might have been playing with too much anti-skate, and excessive VTF.

When I took the headshell off to check the cartridge alignment, I noticed that the cantilever looked a bit skewed towards the outer edge of the platter. Anyway it’s now realigned (yes I did use the mill!), my eyeballing was withing 200 microns / 8 thou for overhang, it’s now within 30 or so microns, likely better than the original manufacturing was toleranced. It was hard to measure parallelism with the plastic housing but it’s as square as it can be.

So now with the least anti-skating I can apply and 1 gram of VTF (force gauge coming so I can verify that), I’m getting better channel separation and more resolution in the midrange and treble particularly.

I was all set to return my copy of the Stone Roses 2018 reissue, as it sounded completely flat and lifeless, but I gave it another spin last night and was thoroughly enjoying myself

 

[tnsilver]

So now with the least anti-skating I can apply and 1 gram of VTF (force gauge coming so I can verify that), I’m getting better channel separation and more resolution in the midrange and treble particularly.

1 gram of VTF on a Denon DL-110 is unusual. It is 33% lower than the minimal recommended range (1.8g +-0.3g) - which is plenty. In my general experience with carts, and the DL-110 in particular, the Goldilocks VTF is typically in the upper 1/3rd of the recommended range. Wait for the digital scale. I think something with the CW and dial scale on your UA-7 is either throwing you off and results in the wrong VTF reading, or suffers some inaccuracy.

BTW, the best way to identify IGD is to listen to sibilance. That's when 's' starts to smear over and sound like 'shsssssss'. If it's noticeable more on the inner groove - that's inner groove distortion.

 

[rbphoto]

Wait for the digital scale. I think something with the CW and dial scale on your UA-7 is either throwing you off and results in the wrong VTF reading, or suffers some inaccuracy.

Yeah that’s my suspicion. Trusting the dial scale might not be doing me any favours.

BTW, the best way to identify IGD is to listen to sibilance. That's when 's' starts to smear over and sound like 'shsssssss'. If it's noticeable more on the inner groove - that's inner groove distortion.

Yeah, I can not say I’ve experienced that yet, many other things but not sibilance. Apologies for my poor use of terminology!

 

[tnsilver]

Take it easy on the M. Fremer medicine too. It's like pot. It can be fun and harmless, but excessive use can lead to seriously abusive stuff.

 

[patient_ot]

See if you can PM a mod to change the thread title for you. Your problem has nothing to do with IGD. It is due to warped and off-center records. I agree the digital scale is a good cheap tool to have around no matter what turntable you have.

 

[Bicyclist]

The scale is an excellent tool.

 

[Mr Boochie]

Back to the actual diagnostic stuff, I have a feeling I might have been playing with too much anti-skate, and excessive VTF.

When I took the headshell off to check the cartridge alignment, I noticed that the cantilever looked a bit skewed towards the outer edge of the platter. Anyway it’s now realigned (yes I did use the mill!), my eyeballing was withing 200 microns / 8 thou for overhang, it’s now within 30 or so microns, likely better than the original manufacturing was toleranced. It was hard to measure parallelism with the plastic housing but it’s as square as it can be.

So now with the least anti-skating I can apply and 1 gram of VTF (force gauge coming so I can verify that), I’m getting better channel separation and more resolution in the midrange and treble particularly.

I was all set to return my copy of the Stone Roses 2018 reissue, as it sounded completely flat and lifeless, but I gave it another spin last night and was thoroughly enjoying myself

You may want to think about buying a test record. To help with setup and tracking issues.

https://store.acousticsounds.com/d/95088/Tacet-Vinyl_Check-180_Gram_Vinyl_Record

 

[kyle]

Back to the actual diagnostic stuff, I have a feeling I might have been playing with too much anti-skate, and excessive VTF.

When I took the headshell off to check the cartridge alignment, I noticed that the cantilever looked a bit skewed towards the outer edge of the platter. Anyway it’s now realigned (yes I did use the mill!), my eyeballing was withing 200 microns / 8 thou for overhang, it’s now within 30 or so microns, likely better than the original manufacturing was toleranced. It was hard to measure parallelism with the plastic housing but it’s as square as it can be.

So now with the least anti-skating I can apply and 1 gram of VTF (force gauge coming so I can verify that), I’m getting better channel separation and more resolution in the midrange and treble particularly.

I was all set to return my copy of the Stone Roses 2018 reissue, as it sounded completely flat and lifeless, but I gave it another spin last night and was thoroughly enjoying myself

You don't necessarily want the cartridge housing to be square to the gauge. You want the stylus to be square and if, as you mention, the cantilever is skewed when not on the record try aligning the cantilever instead. If it's bent or badly misaligned you're screwed but if it's just a bit off it can still sound better than using the cart body for alignment.

 

[Ken Boyd]

Don't expect the tone arm VTF weights to be that off. Most the time if you balance the tonearm well those marks on the knobs are pretty close to accurate. But owning a digital scale is a good tool, it helps to convince the mind that those scales are usually pretty close.

 

[rbphoto]

Take it easy on the M. Fremer medicine too. It's like pot. It can be fun and harmless, but excessive use can lead to seriously abusive stuff.

Haha yes, I'm in it for the factory tours, I always appreciate seeing how people do things and organise their shops, and geeking out on machine tools, and seeing the deadpan expressions of engineers when he says stupid stuff. I wanted to punch him when he told the SME engineer that his old machines were "like, stone age, man". As if mechanical precision was a recent concept! I think I could happily spend the rest of my working life hand-finishing SME tonearm parts. What a cool job.

You may want to think about buying a test record. To help with setup and tracking issues.

https://store.acousticsounds.com/d/95088/Tacet-Vinyl_Check-180_Gram_Vinyl_Record

Yes! Thank you! I didn't even know these existed, but this came up in a Soundsmith article on VTF as well so I think I will get one. Hopefully they come with a certificate of concentricity and planarity, right? J/k. But it would suck if your test record was warped. Why they'd press these on 180 gram vinyl is beyond me.

Together with the microscope and scale I should be set to pursue this somewhat misguided quest for error-free playback.

 

[Ken Boyd]

why not just put them back in their OEM cases?

 

[patient_ot]

But it would suck if your test record was warped.

Newer "test" LPs can indeed be warped and off-center. If you get one of those, immediately send it back. Note also there is a difference between the old style of professional test records for broadcast use and such vs. some of the newer ones which are basically toys for audiophiles.

 

[Mr Boochie]

Yes! Thank you! I didn't even know these existed, but this came up in a Soundsmith article on VTF as well so I think I will get one. Hopefully they come with a certificate of concentricity and planarity, right? J/k. But it would suck if your test record was warped. Why they'd press these on 180 gram vinyl is beyond me.

Together with the microscope and scale I should be set to pursue this somewhat misguided quest for error-free playback.

Acoustic Sound ships their LPs in a boxes which may be able to withstand a major hail storm. Okay, I exaggerate a bit, but they have the best mailing cartons. My test LP is flat, 180 grams. It has a great resonance test track, too.

One note: voice is in German (as the record is German origin). But, gatefold instructions are in English and German. With simple descriptions of what to listen for, in the tracking sections.

Good luck! Hope this LP helps your setup. It definitely helped mine.

 

[tnsilver]

then I discovered the at 440mla and made me a believer.

You sure sound like a believer. Faith aside, care to take a shot at a down to earth explanation for how a micro-line tip could possibly solve an IGD issue that the elliptical tip of the DL-110, let alone the sphere tip of the DL-103R could not? Do you believe this is the solution for a bunch of warped and overly eccentric records? Was IGD even the problem?

I actually believe that anyone who exchanges a DL-103R, one of the lowest compliance carts on this planet for a cart as twice as compliant, such as the discontinued 440mla, and finds the difference appealing - had a cart/tonearm mismatch problem to begin with, which was probably way more acute than IGD.

 

[tnsilver]

I can't find that post that I've quoted earlier. Possibly related to this?