Correct alignment for Fidelity Research 64fx/SPU?


Hello,

I've recently paired SPU Spirit with FR64fx (& additional counterweight).

FR64fx is mounted at 230mm pivot to spindle distance on my Garrard 301.

I currently experience a light distortion and mistracking. As I tried the SPU before on almost ad hoc mounted 3012 and that sounded technically correct (though not as convincing as with FR64fx in terms of emotional performance), I'm pretty convinced I will need to realign the tonearm.

I would appreciate any info related to an experience of 64/SPU users here, which would differ from a usual 230m PTS alignment. Also, I keep on reading that Stevenson alignment would be preferred, is there any explanation why so?

Basically I need to make a good decision as I have no armboard - whatever decision I make I will need to get a new top board with a new hole for a new alignment.

Many thanks!
anubisgrau
@rauliruegas  I should have expressed myself more accurately. Obviously there are tracking errors with any pivoted tonearm. In response to @montesquieu  I should have said "no nasty tracking errors". You see, I don't hear audible distortions using Ikeda's specified 230mm S2P distance for the FR64 in combination with the FR7 cartridges, which were designed to be used with this arm (and the FR66). The same goes for using the FR64 with SPU's: no 'nasty' tracking errors. 

I know you hate the FR64, but I happen to admire Ikeda's designs and I have no reason to doubt that he knew what he was doing when he chose the Stevenson geometry for his products. As far as I'm concerned the sonic results speak for themselves. If you happen to think differently, that's perfectly fine. I couldn't case less.




Dear @edgewear : "  I know you hate the FR64.."

maybe my several posts about through the time give that  conclusion but the FR main subject I don't recomended it ( even that I own it. ) is that it's a non-damped tonearm design.

The tonearm looks really fine but any tonearm needs to " fullfil " the cartridge needs and one critical need on a cartridge is precesily to damp so many kind of resonances/distortions developed in between the LP/cartridge/tonearm.
I know that the FR as SAEC tonearms likes to almost all people because one characteristic is that is so alive as the live MUSIC.

The kind of nice distortuions developed through FR/SAEC tonearms are just that: nice distortions and I prefer more clear MUSIC information with lower " nice distortions ".

This FR/SAEC tonearms example is in some ways similar on why we like more analog than digital or tubes over SS electronics.

So, everything belongs on what be our room/system main targets and mine is try to stay truer to the recording and one path that puts me near to that target is try to leave all kind of distortions generated by the room/system at minimum elsewhere the room/system and a well damped tonearm designs helps a lot to achieve that target.

R.
@rauliruegas we agree to disagree, no problem. In my system using the same turntable and the same cartridges I can compare the FR-64S directly to the Audiocraft AC-4400. As you well know this is a tonearm with variable damping. There's no doubt these tonearms have different characteristics, also taking into account the difference in effective length. But even in direct comparison I don't hear the kind of distortions that you attribute to the FR-64S.


Here is more information about FR tonearm on another forum, the last version was 64FX with damped armtube, then 66fx. Someone posted catalogs, download them if you don't have it.  
@chakster I also own the 64fx (with silver wire inside) and I've made some thorough comparisons between them. I like them both, but ultimately I prefer the 64S (also silver rewired). Especially with heavy low compliance cartridges like FR7 and SPU.