Stylus Rake Angle

Here's a twist. As Dougdeacon so well reminds us, each record is different and styli shapes differ, so it is somewhat futile to fixate on the 92 degrees. However, out of curiosity, I did check to see how close my SRA is to 92 deg. when my arm is horizontal. Very close. So with that for comfort and as a starting point, I adjusted further by listening to a variety of LPs until I found the setting I liked. For me it is a compromise because the VTA is difficult to set with my arm, so I don't do it for each record.

Doug explained to me once what it is that should be listened for. It is not a tonal balance between highs and lows as I had thought, but rather it is a timing issue involving the initial transient, the sustain and the decay. The relationship of each of these for a plucked note on a mandolin or harpsichord should sound natural and have the correct timing.

Rather than corrupting Doug's description any further, perhaps he could once again explain exactly what to listen for when adjusting SRA.

In most of cases the stylus bay should be parallel to the surface of record. updowns should be very slight.

Although the setting the arm at the horizontal position by eye works for most arm/cartridge combos, isn't the advantage of using the microscope to set SRA come down to being able to set a good ballbark VTA for those cartridges that have more unusual cantilever/stylii angles or sylii with unusual sensitivity to SRA (micro line, shibata etc.)?

-Karl

I thought this SRA stuff was over the top but I am not so sure now. I track an old, re-tipped by Soundsmith, Koetsu rosewood signature fitted with an enhanced line contact (original Aeries 1 deck/arm). I read Fremner's article and even downloaded the original '81 article and thought it was worth trying. Previously I have always set the cartridge base to parallel and tweaked from there, usually ending up with the back of the arm a little lower. My system sounds quite good considering the components but some voices, etc. are still not quite right (ssssssss'ing/S's too emphasized occasionally/etc.). Cannot justify currently the price of the digital 'scope so I just did a crude check using a x30 illuminated jewelers loupe with the needle on a CD (so they ARE useful for something). As far as I could tell (and I do use microscopes routinely/microdissections) my SRA was >92o. I therefore lowered my arm significantly so the SRA seemed closer to ~90o (all guesstimates but possibly with a trained eye!) and low and behold the sound improved exactly as Fremner described: smoother more easy, natural sound BUT with more detail! For example I quite like/pretty familiar with the album "Survival of the Fittest" by the Headhunters (Herbie's backing band for his album amazingly called Headhunters!): on one slow track a shaker of some sort moves slowly from right to left producing 3 clear shakes, now I can "see" that shaker shaking clearly in space moving realistically across the soundstage- I was gobsmacked. The difference was minor but to my ears very significant. Now I cry even more when listening to the MFSL pressing of LIVE/DEAD. Everything now seems more psychedelic!(Fremner has used this term too- believable illusions).
So perhaps it might be worth trying it, even with a crappy x30 lens 'cos this crude guesstimate seems to have produced a significant improvement.

This is some good hints on setting VTA.

"Raise the VTA (raise the rear of the arm) and the highs will usually get better. Too much and you will lose the bass.
Lower the VTA and the bass will get stronger. Too much and you will lose the highs."

From:

http://walkeraudio.com/lloyd-walker-on-fine-tuning-your-turntable/

I have been playing with cartridge loading. It is interesting that I hear some of the same differences from loading changes as described above with VTA changes. Nothing ever seems easy. LOL

Bob