Much IGD on LPs? or on EPs? Why? How to manage?

sunder

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Hi friends, when playing the records, after played the second half of the LPs , the Inner Groove Distortion begins. Apart from the wrong

alignment , nature of the stylus or some technical things, are these flaws more evident on 7" or on 12" records ?. Is one of the reason:

Quality of pressing of records? Please share your experiences. Thank you. Regards.
 
Hi friends, when playing the records, after played the second half of the LPs , the Inner Groove Distortion begins. Apart from the wrong

alignment , nature of the stylus or some technical things, are these flaws more evident on 7" or on 12" records ?. Is one of the reason:

Quality of pressing of records? Please share your experiences. Thank you. Regards.

I used to have the same problem. If you have a Technics TT, use the Technics Baerwald Protractor: https://www.vinylengine.com/cartridge-alignment-protractors.shtml Scroll down the page a bit and you will find it. After aligning my cart (basic conical Audio Technica) using this protractor, IGD has come down drastically. On some records it is non existent. Please note: on records where the inner grooves have been ruined by a previously misaligned cartridge, nothing can be done (aside from using a microline stylus).
 
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Ok, will get it. As you said, we are getting records in the status as it was already beaten by the previous owners who was unaware of the damage.
We have to accept as it comes as nothing in our hands. Thanks.
 
Ok, will get it. As you said, we are getting records in the status as it was already beaten by the previous owners who was unaware of the damage.
We have to accept as it comes as nothing in our hands. Thanks.

Sorry I meant Technics Arc Protractor. Make sure the stylus tip follows the arc throughout, without moving the protractor. You will not be disappointed with the outcome...made a big difference for me.
 
"I use Technics default overhand gauge and Arc Protractor to avoid the IGD. Never felt such an issue. I listen to lots of 7" EPs and SPs which is very pivotal to my listening genre.
 
If using a Technics TT, the overhang gauge is a real blessing. Set the correct overhang as per the gauge, while ensuring that the cartridge is mounted straight in the axis of the arm tube and lateral (left/right) spacing on the headshell is equal, this is sufficient alignment. No further protractor needed. Also, Technics doesn't use a standard Baerwald or Lōfgren or Stevenson geometry, though it's reportedly closest to Stevenson, so it makes sense to use the overhang gauge.

In the absence of an overhang gauge, what I used to do is set overhang (52 mm, IIRC) using a ruler with half mm markings. It's fairly accurate too.
 
Set the correct overhang as per the gauge, while ensuring that the cartridge is mounted straight in the axis of the arm tube and lateral (left/right) spacing on the headshell is equal, this is sufficient alignment. No further protractor needed.

Do you mean: When the setting is done perfectly as you said above with the 'Overhang gauge' , then there is no need any alignment on the two positions (Grid1 & Grid2) with protractor ? Thanks.
 
Do you mean: When the setting is done perfectly as you said above with the 'Overhang gauge' , then there is no need any alignment on the two positions (Grid1 & Grid2) with protractor ? Thanks.

Yes I think the same too. Overhang gauge sets the right positioning and the 52mm trick also worked fine for me before procuring the overhang gauge. For another TT Sansui FRD3 I have, protractor works fine.
 
I used the overhang gauge at first, but found a marked improvement in reducing IGD using the arc protractor. Also I'm planning to try the Conrad Hoffman protractor generator and see which works better. The beauty of turntables is the tweaking factor...lots of stuff to try out:)
 
I used the overhang gauge at first, but found a marked improvement in reducing IGD using the arc protractor. Also I'm planning to try the Conrad Hoffman protractor generator and see which works better. The beauty of turntables is the tweaking factor...lots of stuff to try out:)

Yes, please try the Conrad Hoffman. I use it after fellow forum member here Hari Iyer told me about it. I really, really like the arc protractor. Earlier I used to generate data using the Keith Howard arcgeometer application (please check out his website - it's a treasure trove for analog guys), and used to create my own custom protractor that combined correct overhang and offset angle in one sheet.
 
Do you mean: When the setting is done perfectly as you said above with the 'Overhang gauge' , then there is no need any alignment on the two positions (Grid1 & Grid2) with protractor ? Thanks.

Yes, Sunder. The Technics overhang gauge is sufficient.
 
Yes, please try the Conrad Hoffman. I use it after fellow forum member here Hari Iyer told me about it. I really, really like the arc protractor. Earlier I used to generate data using the Keith Howard arc geometer application (please check out his website - it's a treasure trove for analog guys), and used to create my own custom protractor that combined correct overhang and offset angle in one sheet.

Thanks jls001 Will definitely check out the Keith Howard website...just confirming - is this the link- www.audiosignal.co.uk ?
 
Yes, please try the Conrad Hoffman. I use it after fellow forum member here Hari Iyer told me about it. I really, really like the arc protractor

jls001, can Conrad Hoffman Arc protractor be used for Pioneer TTs or only for Technics players? Thanks.
 
jls001, can Conrad Hoffman Arc protractor be used for Pioneer TTs or only for Technics players? Thanks.
It can be used for any TT.Conrad Hoffman is a protractor generator on the vinylengine website.You need to download the .exe file and click on it. Then fill in the correct parameters as per your TT and click on the print button. It will print out your protractor ready to use.
 
A micro wiki/primer:
You can generate protractors based on three (quoting this from memory so I may be a bit off on the number) different types of geometries using the Conrad Hoffman generator. The differences of these geometries is in the way they minimise the tracking error. For example, Baerwald tries to have uniform error from the outermost to innermost groove. Similarly, Stevenson tries to minimise error in the innermost grooves.

So besides choosing the geometry, you need to choose what you consider the outer and inner null points of a record. There are multiple standards defining this important data. Vinylengine is a good source of such info.

Once these choices are made, the protractor is generated by the program. The differences in the different protractors will be in different overhang and different offset angles.

Now, the need to adjust overhang requires that the headshell hole must be slotted, and not a single hole like in some headshell designs.

A slotted hole also allows one to adjust the offset angle.

Adjust as per the new protractor and hear how IGD sounds.

Also, please note that cartridge adjustment must be in reference to the cantilever, and not the body of the cartridge itself because the cantilever itself could be slightly misaligned from the factory. Also, not all cartridges have nice square shells that could be used as ready reference.

Good lighting, magnifying glass, patience are key ingredients.

PS: using the Keith Howard Arm Geometer you can generate with your own chosen geometry (do look up Keith Howard's excellent article in Stereophile written when he was a contributing editor, available from the Stereophile archives). It's a bit math heavy but it can be considered a seminal paper on the subject.
 
Stevenson tries to minimise error in the innermost grooves.

I think, this Stevenson will be good for playing 7" records than the other. Isn't it?


please note that cartridge adjustment must be in reference to the cantilever, and not the body of the cartridge itself because the cantilever itself could be slightly misaligned from the factory. Also, not all cartridges have nice square shells that could be used as ready reference.

But, when using the Overhang Gauge, the cartridge body should be well aligned along with headshell . Am I right?

Thanks.
 
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