How to set SRA after determining true vertical?


Here is a picture of a stylus with zero rake angle:

http://members.cox.net/nsgarch/SRA@%200.0%20deg.jpg

Since all modern styli are symmetrical in the x and y plane about the verical z axis, the tapered stylus and its reflection will make a perfect "X" when vertical (z axis perpendicular to the groove) and viewed from the side.

This condition is established by raising or lowering the tonearm pivot post. Once you find this point, and assuming you have a typical 9" tonearm (about 230 mm from pivot to stylus) then each 4 mm you raise the post from the zero
SRA point will apply one degrewe of SRA to the stylus.

A test setup is shown in these two pics:

http://members.cox.net/nsgarch/SRA%20setup1.jpg
http://members.cox.net/nsgarch/SRA%20setup2.jpg

Equipment includes:

a mini Mag-Lite flashlite,
a first surface mirror from old SLR cameras -- easy to find at photo repair shop)
a 50X pocket microscope
bean bags

Don't forget to first remove antiskate and set VTF.

.
nsgarch

Showing 8 responses by rauliruegas

Dear Sirspeedy: Tks for all the Lp info.
+++++ " ,there is a series called "The Twilight Zone"! " ++++

Well, this is the first time I read about these recordings. I will try to get it.

Regards and enjoy the music.Raul.
Dear Neil: I'm with you about: " Listen first to bass. ".

What happen in this frequency range has a high influence in the whole percieved sound , if it is bloated then we have a " darkness " that preclude natural/transparent sound but if it is muddy then the music foundation " is not there " and you know it. When the bass frequency range is spot on : the whole thing are spot on, at least this is my experience.

Sirspeedy: " It's all too easy to "think" we have good bass..."
Well, yes it is too easy: for the people that are not too experienced or to the people that are not in " touch " with the live music.
Your high frequency approach is a valid one too but I think is a little more " volatil " than the Neil one ( bass range ).

It is curious, I have a record that is one of my reference ( the top one ) LP for to know how near/far I'm from the " spot on " and in this record I'm not looking for any of both frequency extremes: I'm looking in the mid range. This record is one from Janis Ian ( Breaking Silence ): side 2 track 1: here it is ( at the middle ) a battery sound that when the drummer hit it you know when its right and when this recorded " battery moment " is " spot on " every thing is right, till now never fail.

Regards and enjoy the music.
Raul.
Dear Sirspeedy: " but I don't like to adjust to each record. ". I'm not either.

" Also,I use a number of lp's to make my "averaging". ". I also do the same.

Well, I like Ricky Lee Jones, as a fact a like the Music almost any kind but heavy metal ( I own some heavy netal LPs???? !! )

Regards and enjoy the music.
Raul.
Dear Sirspeedy: Yes those original Perez Prado/Tito Puente and the like latin music were great and today we can“t find nothing nearest. Like you, I love Santana too.

I think that not only in this music genre but in classical, jazz, pop, blues, rock, etc, etc, we are in decadence from many years to now: the great composers and interpreters all dissapears: are " things " of the past.
There is nothing growing up about: where are the Bethovens/Stravinskys,Mhalers, Beatles, Fitzgeralds, Miles, Evans, Peres Prados, Jobim, Caruso, Callas, Streisands, Presleys and the like ?. The new generations about are on a lesser/different level and maybe I don't understand exactly their " music " flavor.

Regards and enjoy the music.
Raul.
Dear Sirspeedy: I think that the best orchestra music it is making on the film soundtracks: Zimmer, Horner, Williams, Newton Howard, Kloser, Vangelis, etc.

All these recordings are almost only on CD. Many of them are great compositions.

Regards and enjoy the music.
Raul.
Dear Sirspeedy: Now that you mentioned there are very good compositions on the film soundtrack kind.
Zimmer, Horner, Williams, Newton Howard, Kloser, etc, etc, are very good ones.
Unfortunatelly almost all these kind of recordings were only in digital format, well not unfortunatelly: fortunatelly exist ! ! !.

Regards and enjoy the music.
Raul.
Dear Doug: +++++ " But we keep trying, " +++++

Yes we do.

Regards and enjoy the music.
Raul.
Dear Neil, Greg, Doug: This thread is really informative for all of us, unfortunatelly we can't do nothing different that what we all already do to set up the right SRA and as a fact we can't set up the correct SRA, our best is only an approach.

The main differences here are our ears frequency response at both extremes of the frequency range, our patience to setup the SRA on each record/track or to conform on an average figure, the accuracy of the RIAA eq. on our phonopreamp, the cartridges that we own ( stylus design ) and certainly our tonearms, our experience with live music and in the case of tube electronics: with which kind of " temper " wake up the tubes " that " day.

Regards and enjoy the music.
Raul.