Ikeda IT-407 tonearm geometry


I’ve read all there is to read on this subject and never got satisfaction. It inspired me to ask this question earlier.
“Cartridge alignment with non slotted headshells”. 
The main reason I have a problem with these headshells is with my Ikeda it407 (chrome) tonearm, the cartridge must be twisted quite a bit in towards centre.  I have a vintage audio technica headshell with fixed holes and I don't even need a protractor to see that it won’t work. I don’t think stevenson alignment is this bad? I don't have a protractor with stevenson. My pivot to spindle distance is set perfect using my smartractor. I’m quite sure it is not possible to use an spu headshell in my Ikeda with the tonearm at the recommended distance without being seriously out of alignment. I’ve researched this online and I’ve spoken to Bill Demars at Beauty of Sound.  He said that the recommended pivot to spindle distance is probably wrong and some people position at a further distance. He agreed about spu in spu headshell in the ikeda arm not being ideal. I’ve never heard if anyone has asked Ikeda these questions about their arm. 


I do really like this arm, the way it sounds and the fact that is has a removable headshell, 
I’d just like to have better understanding of it? 



sdrsdrsdr
I thought I would try Stevenson but I keep hearing how poor it is. Maybe uni-din is a better choice. Check this out.

Bad things about Stevenson alignment coming only from one user on this forum, many others are happy with Stevenon and can’t detect any problem using headshell integrated cartridges like SPU or FR-7 series with Fidelity-Research or Ikeda tonearms.

You have to check and decide for yourself.
I’m using Baerwald on some of my tonearms with many cartridges when re-alignment is not a big deal using proper headshells.

Anyway, maybe i’m just not so old to hear distortion, i can’t say anything bad about Stevenson alignment method and if you will read more about it there was the reason to invent this geometry, especially for those who’re into classical music.

Uni-Din is interesting. But although I am not sure that it's worth the effort.

In most of the records crescendo occurs in the very end (at least in classical and jazz) so with cartridges like SPU which are not the best trackers I do feel more safe to have Stevenson as it less possible that it will damage inner grooves of record.

My proposal is if you do any changes by yourself buy test record and use tracking tests as after trying different alignments you have to be sure that you haven't made some hard errors then aligning cartridge.
Dear @sdrsdrsdr  : There is no problem with Ikeda geometry. The problem is to understand how the tonearm/cartridge set up alignment works.

Forgeret about the Ikeda specs because you can change the effective length of any tonearm changing the pivot to spindle distance ( not making the change through overhang. ) and use an alignment calculator to set up your cartridge to the new parameters.

You have to " play " with that effective length change till you find out the one for that cartridge.

https://www.vinylengine.com/tonearm_alignment_calculator_pro.php

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.


@bukanova

 In most of the records crescendo occurs in the very end (at least in classical and jazz) so with cartridges like SPU which are not the best trackers I do feel more safe to have Stevenson as it less possible that it will damage inner grooves of record.

Exactly, i can only remind others that we have not only big "12 inch records, but smaller "10 inch EPs and "7inch singles. On smaller format of vinyl there is nothing located that far from the center hole, because the radious of the record is much smaller. I've posted about it before, on "7 inch records everything located in the field where on "12 inch located only last two songs maximum. Stevenson alignment is not for idiots. 

But anyway, most of us using at least two tonearms and we can compare one to another with different alignment methods. I have 4 tonearms in use, some with Baerwald, some with Stevenson, some with manufacturer's own alignment.  

Perhaps I’m an idiot with tin ears, but in my experience the sonic differences between the various alignment geometries shouldn’t be exaggerated. I use FR 64s and 64fx tonearms with the specified P2S distance of 230mm, which means that the geometry is Stevenson by default. This way I can use my FR7 and SPU cartridges with correct alignment. On my Audiocraft AC-4400, using a variety of cartridges in a variety of headshells (slotted or otherwise) I have experimented with the other geometries, including Audiocraft’s own (which is neither Baerwald, nor Löfgren, nor Stevenson).

The sonic difference between these various geometries was so negligable in my system and to my ears, that I decided to use Stevenson for the Audiocraft as well. This way I can use my cartridges in all three arms, without having to make changes to their position in the headshell each time they go from one arm to the next. Yep, I’m a lazy idiot as well.

In my own defense I should probably add that my Reed 3P tonearm with fixed headshell uses the Baerwald geometry. As much as I’ve tried, I’ve never been able to conclude that this set up sounds superior in any way to the others. If anything, I’d say Stevenson is preferable with classical music, as these composer guys like to go out with a bang. You may have noticed this usually happens at the end of the record side, where inner groove distortion is likely to be most severe.