Nsgarch- I found a picture of the groove. Results are inconclusive.
Doug-Just off the top of my head I might get similar results with a router.
I guess the burden of proof is on me.http://aolsearch.aol.com/aol/search?query=pictures+of+record+groove&invocationType=spelling&itaq=0.2.1.KQzKRxLUFAB&itaq=1.0.1.pictures+of+record+groove&itaq=2.1.1.I hope that takes you to a picture of record groove and compact disc digits. If not just type " pictures of a record groove" on your aol browser. Taken by elctron microscope. |
Greg - good pictures! I think the high-mag one shows pretty conclusively that the groove undulations slant -- in this case toward the bottom of the picture (from bottom to top of the groove.) |
Great pix!
If we imagine a line contact stylus trying to trace those modulations, if SRA is off then one end of the contact line will encounter each modulation before the other end. The stylus will shave across the modulation instead of tracing it precisely.
Mechanically (sonically) this will:
1) reduce stylus deflections (reduced micro-dynamics),
2) lengthen the time the contact line sees each modulation (temporal bloat),
3) alter the timing of when the stylus encounters multiple frequencies (loss of temporal focus and timbre) and,
4) alter the frequencies the stylus actually plays (FM distortion).
I hear #s 2 and 3 most easily. Paul is very sensitive to #1. He was able to adjust SRA on Cello's rig just by feeling the pressure waves coming off the woofers, without actually listening at all. Raul says he adjusts by listening to bass, so his sensitivity may be similar to Paul's.
P.S. Those records could use a good cleaning!
|
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. |
http://www.smartdev.com/LT/Align.htm. more drawings. |
See also, http://www.recordcollectorsguild.org |
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. |
Raul,
Exactly right, "our best is only an approach". That is true of everything in audio of course. All the expertise, good will, time and money in the world will not turn a pile of wires and silicon into a violin.
But we keep trying, because it sounds so good when we take another little step closer...
|
Dear Doug: +++++ " But we keep trying, " +++++
Yes we do.
Regards and enjoy the music.
Raul. |
Greg -- what a terrific website (you were referring to the article on Vinyl Microscopy?) My favorite part:
The animal (below) is a young silverfish with its extended cercae overlapping the closing bars of the final movement of Bruckner's third symphony. I mention this as it is not possible to tell from the photograph. There are few places in a Bruckner symphony where the sound of a diamond stylus colliding with a dead silverfish would be less welcome. The cadaver was removed by brushing with a carbon fibre brush. |
Nsgarch, Dougdeacon,
This is a great post. This combined with the John Risch article enabled me to explore VTA positions that I would not have ventured to test before. I am now achieving stellar performance.
Dougdeacon's advice in setting SRA by listening is important. However, what I found the most valuable about this post and related references is that it' s very effective at getting a good starting point and idea about the range of arm psotions that can yield great sound.
Being a novice, I assumed that a parallel arm position was the best initial setting and that one shouldn't deviate too far from that. However, the best position I have found ranges from 1-2 degrees from vertical.
The arm is far from parallel in this range and I never would have ventured this far away from parallel had I not read these posts.
I also agree that listening to the bass perfromance and the HF detail are tell tale signs of optimal settings in SRA.
Thank you!
I hope more people can benefit from this.
Andrew |
I'm right there with you, Andrew. The starting point has always been something of a mystery to me but this thread provides a very repeatable methodology. |
Andrew,
I don't know if Dan_Ed noticed when he visited us a few weeks ago, but our armtube is not level either. It really doesn't matter that much. I rarely hear any sonic effect that I would attribute to armtube angle. What we do hear is best explained by the SRA-matching Nsgarch and Jon Risch described.
Glad to learn you're achieving great results! The more you play around with it the easier it gets to hear. When you start putting little yellow stickies on each LP jacket to record arm height settings, we'll know you've gone over edge - like me! ;-)
|
Hey Doug,time to sell the Mazda and go for the Air Tangent "electro",where you can set VTA by remote and have a cute little digital readout.The price of gas DEMANDS this of you!! |
Doug,
Yellow stickers. Maybe. The more I learn and experiment the more I'm becoming a "believer" in the importance of arm/cartridge parameter optimization. The next step is to experiment with VTF.
Regarding your comment: "I rarely hear any sonic effect that I would attribute to armtube angle", I think you mean that it is not the arm tube angle that you are setting directly. However getting the best SRA requires moving the arm up or down, which invairably changes the arm tube angle relative to the record surface.
SRA = f(stylus angle on cantilever, and arm height)
Arm tube angle = f(arm height)
Correct me if I'm wrong, but the armtube angle, indirectly, does have a big effect on sonic attributes.
|
Hi all,
Doug, I do remember that the arm tube seemed a bit low at the pivot but that could have been the angle at which I was viewing it. I've come to learn not to worry so much about arm orientation thanks to threads such as this.
What most impressed me was how you could make a quick adjustment to the TriPlanar and Paul would either nod, winch or shrug. (He did a lot of shrugging with my rock music. :) Paul practically called me a head banger! I think of myself as more of a head banger with finesse, thank yew very much!) Based on my experiences with suspended tables, I swear there were times when my heart would skip a beat watching you quickly, and seemingly without care, beat about the pivot while adjusting VTA. (Not really, Doug is very graceful.)
Andrew, I see where you're going and I'm inclined to agree. IF the armtube angle is based on SRA then, as Neil has shown, changes in the arm angle do directly affect SRA. Perhaps it is picky, but it is important to realize that in the end it is the SRA that makes the difference.
SirSpeedy, if you start using remotes for everything I can promise you'll end up with a bigger spread than mine. Sorry I'm not going to catch up with all of you at VTV. Maybe sometime soon! |
SRA is irrelavent. It is the position of the stylus in the groove that counts. The maufacturer designed the cartrridge to achieve that with the arm parrallel to the record surface. To the extent you use different forces and angles you may have to raise or lower the arme to restablish that angle. |
If you read Mr. vdH's notes (the Q and A part) on tonearm setup on his website, you'll run across a statement where he flatly recommends raising the back of the tonearm about 6 - 8 mm (from level, or from parallel to the platter), I think it says.
This is actually about right for his vdH cartridges which (most of the time, but not all!) are manufactured with the stylus perpendicular to the top of the cartridge body when the cantilever is deflected under normal VTF.
Following his instructions gives you 1.5 to 2 degrees SRA probably 80% of the time for vdH cartridges (though I still think it's best to check with a scope to make sure.) My point is, that even if you just rely on his recommendation and don't check first, you should still be close enough to the correct SRA to find it by ear without much further up or down adjustment.
Greg's assertion that all manufacturers mount their styli so they have proper SRA when the cartridge is parallel to the platter would be really nice if true, but unfortunately the variations are pretty wide. Even among the products of a single manufacturer. My guess its that it's a difficult parameter to control tightly in real-life production. Also there are three ways I know of for attaching the diamond to the cantilever, so most makers are probably thrilled just to get that pesky diamond stuck to that little boron rod!!
The one thing I've never seen (at least in my economically limited cartridge auditioning experience) is a cartridge which requires the tonearm post be lowered from level (as in "ass dragger") to achieve correct SRA. Anyone who thinks their setup sounds best this way really needs to do the investigation I described at the beginning of this thread. I'm not saying it couldn't happen (never say never) but if I were a tonearm designer, I'd be upset to see my tonearm used this way because it creates a less stable mechanical assembly (relative to gravity) as the vertical pivot center gets closer and closer to, or even lower than!, the stylus' position in the groove. |
Gregadd,
SRA actually IS the position of the stylus in the groove. That's what Stylus Rake Angle means. I think we're both saying the same thing, just in different terms.
Dan,
You're right, our arm is low at the pivot. But that makes the cartridge level, at least on this rig. IME ZYX's like to be level.
I'd hadn't thought about it, but I suppose fiddling with the arm during play on a suspended table could be more exciting than you'd like. It's a non-issue on tables like these, as you saw. I can jump up and down and it won't skip, despite the suspended wood floor.
Paul developed his acute sensitivity to SRA soon after we got our first Teres/OL Silver/Shelter rig. On familiar records he can reliably tell me, "too high" or "too low" from the den, two rooms away. It's a bit nuts, but with exposure and an improving system I find my acuity increasing too. Once you start down that path...
BTW, Paul thinks all rock listeners are headbangers! He apparently grew up hoping the British invasion meant those hooligans were all leaving his native country for good. ;-) If I want the house to myself all I have to do is spin one of my (three) rock LP's. Of course for their own safety I do have to hide them.
Seriously, those shrugs were just us acknowledging that it's harder to hear arm height changes with rock than classical. Amplified instruments often become slightly bloated. Many tube guitar amps are tuned for a bit of roundness of course. That bloat masks the nano-timing cues of small SRA changes. Acoustic instruments with quick rise and decay times respond more audibly. Obviously that is both a blessing and a curse.
Thanks again for coming down. It was great getting together with you guys.
|
Doug's post reminded me that this word "level" is getting tossed around quite a lot. Just so it gets mentioned, the first thing to "level" is the platter. And if you have a suspended table, that means with a clamp and record in place on the platter. (Keep the tonearm in its rest, it won't make any significant difference to "level" in its rest as opposed to sitting on the middle track of the record!)
After that, the position of the tonearm relative to the platter (either parallel or nose-down) will be determined by setting it to provide the proper SRA for the stylus. |
Dan,take a look at the Acoustic Sounds latest advertising.They're selling our little(well,mine)digital guage(95 bucks on Audiogon)for 185 dollars!MAN,we could have bought them all up,and made enough to buy a Blue Pearl!Well maybe a platter mat,for it.
This business of manufacturers making the cartridge bodies to line up one way or another is kinda cute.You have to be careful here,because I can guarantee that plenty of our little cantilever angles are NOT all exact,from model to model.Whomever the mfgr is!The EAR is the only viable way to discern this.But you all knew this anyway.I just wanted some post time.-:)Heh,heh.
PAUL--"To shrug,or NOT to shrug".That question is inarguable to me,as if we want to really hear/know what our favorite "great" cartridges can do,especially the cream of the crop,it seems to be a no brainer to use something like well recorded classical lp's.Or something of that ilk.
I mean to listen for something like the breath being blown,gently through a flute or oboe(for example)trumps an electric guitar being broken over some "groupie's" head!No?Yet that acoustic guitar/singer song writer disc that Cello played for me,really blew me away.No heavy metal,but heavy duty ambiance and gorgeous tonal shadings.I can only imagine how great Larry's set-up must sound by now.
I kinda smile when some audio maven(reviewer) lists the criteria that makes a particular cartridge(or any component)great,and then goes on to list almost all music listed,as hard rock.Oh yeah,you'll notice they throw in one or two classical war horses,to seem interested in that stuff.
Don't get me wrong.I love rock,and have no boundaries in my musical appetite,but when you want to define the sublimeness of a great transducer,nothing compares to listening to the tonal shadings,and harmonic beauty of the instruments of an orchestra.Get that right,and everything else falls into place!Sid always tells me that though something gets a rave,it is meaningless to him,because he has no concept of what that person values in the LP's he listens to.Or what that particular person values in music reproduction.We all seem to skew a bit,in what type of system presentation we favor.It's called individual taste.
Hear that Raul!Enough with the love affair with Heavy Metal!Jan Allaerts SURELY did NOT design his "magic beauties" with the thought of "hooligans banging heads"!-:)
A little humor,if you will,so please no bombs from south of the border.You know you're still the cartridge kin
Sorry for going on so long.It's been three months that my set-up is down.I have nothing else to do!Hey,Mr amp manufacturer,please hurry up.I've got all my other stuff done already.Enough with the hiking cross country!
Best!
|
Whoops! I've said all this before. I keep getting sucked in. Any way vdh's advice sort of proves my point. Think about it. He also had to make the call. If the cantilever is sort of a spring it will deflect under different loads (vtf). Thus if the range is 1.5 -2.2 grams. Then in setting the SRA he had to pick the load producing his optimum sra for that load and arm geometry.
I "believe" that all your are doing is "relocating" that point based on your different load and arm geometry and not duplicating the original SRA of each record. Of course it changes from record to record because record thickness again alters the arm geometry.
Perhaps Doug is right and we are approaching the same solution from a different direction. |
Nsgarch,
I found this to be true as well. Raising the arm at the pivot point by 6-8mm improved the sound dramatically. Better bass extension and tautness (very punchy) combined with more detailed highs.
I tried this compared to a level arm tube postion and sligthly lower height of the arm from true parallel. I found that a lower than parallel arm tube position seemed to bloat and diminish the detail of the bass and soften the highs.
Maybe the "right" SRA of the tip in the grooves compared to the original cut is irrelevant. Maybe all we're really doing by determining our preferred SRA or VTA settings is taming the particular sonic signatures of certain tonearm and cartridge combinations. |
Andrew, don't be skeptical. There is absolutely no mystery here. It's all physics and simple geometry. The most important thing to remember when approaching the matter of setting correct SRA, is to have all the other settings perfect beforehand. IMO, the proper order for setting up TT/TA/cart. is as follows:
1.) Level the platter, and then cross-check to make sure the headshell is level (across, not front to back) -- especially important if the headshell is not adjustable (like an SME V!)
2.) Install the cartridge and adjust the stylus overhang at the spindle.
3.) Adjust the cartridge yaw (rotation as seen from above) to reduce tracking error at two points across the record using one of the many cartidge alignment gauges available.
4.) Set the VTF -- at the top of its range if it's a new cartridge, less if already broken-in. Use a digital stylus gauge that reads to 1/100 gram (two decimal places.) Do not apply antiskate yet. You'll need it off to check the stylus vertical position.
5.) Then set the arm parallel to the platter. By eye is good enough. I sometimes use one of those little round bubble levels. They weigh only .15 gm, so you can put it right on top of the headshell before setting the stylus on the record, without fear of cartridge damage.
6.) Now you can begin the SRA setup process. First find where the stylus is vertical as I explained earlier -- and which was the reason for this thread ;-)) -- and then raise the tonearm post 4 or 5 mm.
7.) Now you can set the antiskate. I do it visually if I can (meaning if I have a high compliance cart. which lets me see the cantilever shift with the application of AS force) Otherwise set it by the numbers. Using a test record can also be helpful.
8.) NOW you are ready to begin listening and moving the tonearm post sligntly up or down from the +4 mm setting.
I cringe when people make absolute pronouncements, but honestly, you must follow this process exactly if you expect meaningful results. |
Nsgarch,
Good points. I pretty much followed your process, however I began with setting VTF on the low range. I'll begin experimenting with higher VTF's and resume the SRA testing.
Thanks.
Andrew |
Doug,
I knew exactly what the shrugs, nods, etc., meant. And interpretting those indicators is what made it so much fun to watch. I hope we can all get together again before too long. I will have another pre-amp by then and quite possibly another phono stage as well. I'll bring more jazz next time so as not to put Paul off so much! :) I believe I also heard some disparagement towards Nashville so I'll leave the Pickin' music behind as well. ;) Seriously, that was very "eye-opening" to hear how much difference there is between recordings of different musical genres.
SirSpeedy, I guess we'll just have to watch as someone else makes the money. Again! BTW, you once warned me about listening to other's systems and how it can lead to a certain amount of displeasure with your own. Well, it's happened to me. But I do think it is a good thing in the end since what most of us are after is to build our systems as good as we can get them. I also agree with you about different music. I'm fortunate to have a friend who is a very highly trained jazz trombonist. He's taught me a lot about jazz over the last two years so I'm beginning to gain an appreciation for it. Classical is going to take me a while longer but I do have many fairly good recordings both on vinyl and cd. |
Andrew, I only mentioned the business about setting new carts' VTF at the high end of the range because it is necessary to do that in order to get the cantilever/coil assembly to "line up" squarely in the magnetic flux field (maximum output).
Later on, after about 100 hours of being compressed under record playing conditions, when the rubber suspension "limbers up", a somewhat lighter VTF will be sufficient to achieve that same proper mechanical alignment of the coils in the flux field.
Again, there is no magic involved here. In fact, as far as I'm concerned (here we go!!) the only criteria for the correct VTF setting is this alignment of coils in the magnetic flux. If you have that right, and the SRA and AS are on the nose, there should be no tracking problems (the most common reason for fiddling with the VTF).
If for some (other) reason your cartridge still won't track, look elsewhere, especially for possible compliance vs. eff. mass mismatch with the tonearm. |
I will have another pre-amp by then and quite possibly another phono stage as well. Dan, I don't know how well you liked ours, but if an Alaap interests you at all let me know. I'll put you in touch with Nick and - crucially - tell him you're an okay guy! I'll bring more jazz next time so as not to put Paul off so much! :) Nonsense! It'll do him good. I do agree with SirSpeedy and his buddy Sid however. Nothing reveals what a system or component can (or cannot) do better than challenging classical. We didn't subject you guys to opera or large scale choral music, but they are the acid test. I have a few records that were comparatively unlistenable until Nick's components showed up. Our old c-j stuff just couldn't cope. My Nashville crack was only that of course, and pretty d@mn funny if I may say so! Michael introduced us to 'Trio' by Dolly, Emmy Lou and Linda. We enjoy that LP so much it's never found its way into the record library upstairs. It lives in one of those I-may-want-to-play-you-again-soon baskets in the living room. There's a song on side one I still can't listen to without tears, since it reminds me of Lugnut. |
Dan,you may have taken me a bit too literally.You like Jazz!So do I.If you would like to move a bit towards the Classical genre,start listening to some composers like some of John Zorn's film music(only available on digital,but superbly recorded),or Bernard Herrman's output.Jacob Druckman,Ernst Toch's chamber stuff,Gordon Jacobs,Frank Zappa's -Yellow Shark(CD,but who cares,it's great),any music by "Bang ON a Can"(CD),Ralph Shapey,Elliot Carter etc,etc.Go to a Barnes and Noble,and dial up the music on their computers,and welcome to a "New World"!That's what I love about the "flow of new music discovery".Sort of like discovering new foods.Loads of stuff out there,for the "explorer" of new aural worlds!
Best! |
Excuuuuuze me, but when did this turn into a musical preferences thread? |
Chill out, Neil! We're having fun! You're right, of course. Sorry to car-jack your thread. I've bookmarked it for reference when my next table shows up. It's been almost 6 months. I think I getting hives! |
SirSpeedy, I tried to send you an email but it doinked. Please contact me off-line. |
Dan,you can E-mail me at Sir Speedy 7068@earthlink.net(just leave out the "0" in my usual 70680).
Best! |
T thought I'd better come back and make ammends to this thread by posting something useful. :)
If anyone is looking for a source for front surface (aka first surface) mirror I can recommend a couple of internet sources.
www.fsmirrors.com This site is perhaps the better choice of these two with better prices and selection. There is a 4"x5", 3mm (1/8") pre-made for about $21 shipped.
www.anchoroptics.com This site has a commercial grade pre-made mirror that is about 2"x5" and 3mm thick for maybe a dollar or two more. |
Very interesting,
Thanks to all! |
http://recordcollectorsguild.org/index.php?name=Sections&req=viewarticle&artid=8&page=2
The Record Guild
I posted this before, but they have rebuilt there site. If you have the latest computer graphics, you can see magnificentt detail of record groove and stylus. This is the picture of the dead silver fish and fungus growiing in the record groove. Enjoy!
Gregadd |
