How to set SRA after determining true vertical?

Greg (and anybody else who seriously wants to know how this all works,) check out this page: YOU ASKED FOR IT !!

http://aardvarkmastering.com/westrex.htm

Note: until you get down to picture no. 9, you are only shown one coil, but pic. 9 and 10 clearly show both coils (at 45 deg. to the horizontal, 90 deg. to each other) each with a pin or "link" that is soldered to the torque tube. The cutter head or stylus is installed in pic. no. 11.

At the bottom of this page (I finally found one) is a line diagram of a Westrex cutting head:

http://aardvarkmastering.com/history.htm

Any questions?

i have a question, how can one adjust correct vta, without using microscopes and other equipment ? I use a Dyna. 17D on a JMW-9 tonearm, how would i be sure that the angle of the stylus is correct ?

Readster, basically, you're on the money or you're not. HOWEVER, it's perfectly valid to take the position that if you could get kinda, sorta, close to the money, you could live with that.

Here's how I'd go about doing that:

First, let me say that of a few different cartridges I've inspected (plus what I'm learning from folks who have taken the time to check using instruments) it appears that all cartridges with micro-ridge styli are built with SRAs in the following range:

At one end of the range, the stylus is vertical in the groove when the cartridge (top surface) is parallel to the record/platter. At the other end of the range, the SRA is around 1.5 deg. when the cartridge top surface is parallel to the platter.

In other words, if you got your cartridge parallel to the platter (which generally means your headshell and tonearm too) then you know this much: the SRA is somewhere between zero and 1.5 (+/-) degrees.

Let's say from this level position, you arbitrarily apply 1/2 degree more, or about 2 - 3 mm. at the tonearm post. So now you know that the SRA is somewhere between 0.5 degree and 2 degree (depending how much or little SRA was built into the cartridge initially) but of course you don't know which end of this range your particular stylus is at.

However you can tell by listening, IF you know what to listen for. Unfortunately, this kind of "informed listening" ability is most usually gained by my making SRA adjustments up and down from a correctly set SRA.

But basically it goes something like this (assuming everything else is set up correctly -- load, VTF, ASF, overhang, tangency, etc.):

Listen first to bass. Write down what you think you hear. Is there enough? If yes, how does it sound -- crisp with slam and attack or sort of rounded and/or muddy. If there's not enough or it sounds thin, then you have too much SRA. Reduce it until you have good clean bass without bloat. If it sounds bloated and muddy after you obtain good bass response, then you've gone too far, back off a bit.

Then (or if bass was OK to start with) listen to highs and midrange. If it sounds glarey or grainey or harsh in any way, it usually means (unless it's something else in your system) the you have too much SRA. Usually you won't have very good bass either, which confirms it's the SRA and not some component or cable. Reduce the SRA until the highs are silky. Still not enough bass, reduce the SRA a bit more, it won't affect the highs that much.

Were talking about tenths of a millimmeter here. So get yourself a set of automotive feeler gauges to help determine how much change you apply to the tonearm post (unless you have a TA that provides for easy adjustment of SRA/VTA)

Once you've got good tonal balance, see how you feel about image/soundstage. This is very cartridge/arm/TT dependent. But as anyone with a SRA-adjustable tonearm will tell you, there is one magic (SRA) spot with every record where the audio hologram just snaps into focus. It's very obvious and thrilling to hear.

thanks Nsgarch, for the great detailed explanation, that will help alot.

Nsgarsh,as usual,is correct regarding aural adjustments,and listening for bass.However I have found that though "the bass thing" is high on everyone's list,what really locks in the "now we're in the ballpark" area is extreme high frequency reproduction,played back at a good respectable level(NOT cracking plaster,though),and concentrating on tonal purity at these frequencies.Also,something like a triangle,being struck repeatedly,or better yet,some handbell music(A handbell choir will have a huge variety of fine inner detail,and hopefully superb naturally resonant inner textures at high frequencies).

What should be keyed on is trying to voice to the PUREST textures.This should come across as almost sweet,without the colorations normally associated with that word.

It's all too easy to "think" we have good bass,and this can leave a gap between fine sound and "spot on",which is the Grail, all of us seek.

A few LP's to consider(not that there aren't loads of others,but these are superb,though possibly hard to find)-----Ancient Airs and Dances of Hungary(Harmonia Mundi).---Music of Ancient Greece(Harmonia Mundi)--The Pealing Bells Of the Westminster Handbell Choir,this one is UNBELIEVEABLE,also can be found for about a buck(on the Omni-Sound label)---the soundtrack to the Bdwy play RASHOMON,another incredible disc,"worth it's weight in styli",and has some amazing and different/unique high freq instrumentation,with gorgeous different music(the Carlton label,which was pressed by U.S.Mercury)---Seventy Six Explosive Percussion Instruments,a direct disc on the Sonic Arts label.This is not what you may think,and has gorgeous subtle instrumental textures,as well as bang.------Russo's "Street Music",coupled with An Amer in Paris,on Deutch Grammaphone,killer sound with a harmonica that should seem to be played by Casper the Ghost,floating between your speakers.----EMI-Rachmaninoff's Vespers(pressed in USSR,but fabs),this has a TON of massed voices at almost constant crescendo level,and will immediately tell you if the arm/cart is dialed in correctly,or it will sound like steel wool.A killer disc(so good,you almost need nothing else).---Lastly---------The EMI boxed set of Penderecki orchestral music(I think three discs)containing the JAW DROPPING Harpsichord cto,which will knock anyone out of the "listening chair"!!----Oh,I forgot to mention "The Music of Franz Waxman",on the RCA label(prefferably English,but I have the U.S. pressing)Here is some great stuff,but the Piece d'la Resistance is "Bride of Frankenstein,Creation of the Female Monster" ,INCREDIBLE,FANTASTIC,STAGGERING,and actually lovely harmonic music.My pal Sid(the LP KING,for new discoveries)surprised me with this,some time ago,and just before Halloween.A real treasure!!High frequencies,and "LOWS" you NEVER KNEW YOU HAD.Guaranteed!!!

Let's face it--Analyzing equipment is great fun,but we do it for the MUSICAL PLEASURE,and great "FINDS",that seem to be available only on LP!!

Hope I didn't waste this post,with these,but they have proved invaluable(along with countless others)for helping to dial in my set-up,as well as some of my friends.The music,and sound are all "to die for",as well!

Best!!