Ikeda IT-407 tonearm geometry

@chakster 

Yes. It got a little off track. I’ll have to get a protractor for Stevenson and give it a try. You said your short  ikeda lined up properly without having to twist The cartridge in the headshell. Using Lofgren I have to twist my cartridge quite a lot in my long ikeda.  So much so, that I’d be surprised that Stevenson would be much different. But I haven’t tried yet so I can’t say for sure.


As I said in my opening question, I did speak with the USA distributor and never got clear answers either. He did say that many people preferred a longer p2s. And he uses a longer measurement than recommended too. Then Raul gave his recommendations for it407 and his p2s was shorter than recommended. I was just hoping for a more general consensus. I will get a Stevenson protractor and hopefully have a better understanding.

Steve.

Steve, with your name you must get Stevenson
sorry, it was hard to resist :) 

Seriously, always try first what manufaturer recommends, Ikeda-San is the legend in High-End world. 

You can ask @halcro for his FR-66s PS distance, it must be the same as Ikeda 407. 

Dear friends: I posted that any one of us can manipulate in any tonearm any of the input alignment calculations and this means that each one of us can have a self " designed "/dedicated propietary alignment.

That’s what the SAT tonearm did it when he refused to use the input parameters of the standard inner/outer groove radious and that’s why the SAT tonearm must be aligned by the seller/distributor. Has any advantage what he did it? not really because we can use Löfgren A/B there and evertthing will be fine.

It does not exist any NEW alignment as that DIN that an Agoner posted. What the gentleman down there did it was a manipulation of the input most inner groove radious. He took 54.00mmm for that distance and use Löfgren B alignment and that’s why in the analog planet link appears those null points values.

Here an easy calculation about where any one can corroborates what I’m saying:

https://www.vinylengine.com/tonearm_alignment_calculator_pro.php?arm1=Arm+1&l1=el&a1lv=307&a1=la&oh1v=&oa1v=&arm2=Lofgren+A&l2=el&a2lv=307&a2=la&oh2v=&oa2v=&arm3=Lofgren+B&l3=el&a3lv=307&a3=lb&oh3v=&oa3v=&arm4=Stevenson&l4=el&a4lv=307&a4=st&oh4v=&oa4v=&og=iec1&ogv=&ig=cus&igv=54.0&cal=y&submit=calculate

any advantage?, no only higher error. Btw, I have not a LP that been recorded at 54.00mm inner groove radious. So that data manipulation is futile and useless for say the least. Vive le IgnoraCE ! ! ! ?

Obviously that due our normal low knowledge levels on this alignment specific subject those kind of data manipulations looks as something new/invention. Those gentlemans are taking advantage of our ignorance levels about and nothing more.

R.

dEAR @sdrsdrsdr : """ Then Raul gave his recommendations for it407 and his p2s was shorter than recommended. I was just hoping for a more general consensus. """

YOU HAVE A TOTAL MISUNDERSTOOD ON ALMOST ALL WHAT i POSTED HERE.

It’s normal your misunderstood when M.Fremer ( in those times. ) had a bigger misunderstood on the overall subject and this is what I’m talking about and why I posted what I posted in your thread: for we can understand it and seems to me you did not yet.

This is what I posted on the 407 and I took the manufacturer effective length specification ( one of input alignment calculations. ), I did not change it. The P2S is only one of the calculation outputs achieved by difference in those calculations using Löfgren A and is not  my recomendation but a result of the calculations:


""""""" P2S: 293.718 . I used and use Löfgren A. Many years ago I used Löfgren B. Before I learned my tonearm set up always was made according manufacturer specs, not any more.

https://www.vinylengine.com/tonearm_alignment_calculator_pro.php?arm1=Arm+1&l1=el&a1lv=307&a1=la&oh1v=&oa1v=&arm2=Lofgren+A&l2=el&a2lv=307&a2=la&oh2v=&oa2v=&arm3=Lofgren+B&l3=el&a3lv=307&a3=lb&oh3v=&oa3v=&arm4=Stevenson&l4=el&a4lv=307&a4=st&oh4v=&oa4v=&og=iec1&ogv=&ig=iec&igv=&cal=y&submit=calculate """"""""




Got it? That alignment can be use exactly for the FR66 too following the manufacturer EL spec.

Any thing different down there is only input/output number manipulations with out foundation but any one can do what any one wants it. Anyway, Ikeda-san is an ignorant on the overall alignment subject and its advantages/disadvantages. Period.

R.

@rauliruegas 


I’ll have a look closer at what you said later tonight. At the moment I still don’t quite understand. I appreciate all the input though. I’m really enjoying learning more about vinyl playback. I’ve always been into vinyl except for a while in the 90’s. Before the last couple of years, I only had a single table set up, usually without changes for years at a time. The last couple years I’ve gotten into multiple tables, arms and cartridges and having more fun than ever.