TT setup questions...

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Joey_V

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Hey Vinyl Gurus,

I need some help from you folks.

I set up the Scoutmaster with the help of my dealer (over the phone) yesterday. Being my first TT, I feel like I have a long way to go before I have this TT working at tiptop shape.

My first problem is the image..... I feel like it is definitely skewed to the R. When I switch back to my digital front end (same song), the image is dead center. Now, when I switch back to the TT, the image is skewed to the R.

I noticed that although I correctly balanced the tonearm and cart at 2g via a Shure gauge, I found that the counterweight on the JMW9 arm is a bit off kilter. It seems to make the arm "roll" a little towards one side.

Is this what they refer to as "azimuth"? Does this affect the image? I don't know how to adjust the azimuth properly...

I crudely tried to center the counterweight a bit more on the JMW9 and I got to get the image a bit more center... but it's not good enough yet.

At the moment, I lack a bit more of the vocal weight down center but everything including dynamics and bass is improved.

Any tips to improve would be helpful.

Thanks!

Joey
 
am not a guru, but it sounds like you need a protractor to nail down your cart alignment. perhaps you could check that first. i'd be careful playing too much with the counterweight to compensate.

congrats on your tt! nice cart too!


(we'll need a new name for your pathology... analog has a nasty habit of turning a relentless hobby into an absolute obsession)
 
The JMW 9 is, as you know, a unipivot arm. The azimuth should be set so that the generator mechanism in the cartridge is at a 90 deg angle to the surface of the record. Since you can 't see the generator, you need to set it by ear. The offset counterweight is how you adjust the azimuth. Twist it a tiny amount and listen until you get the image centered. This will take some time but you'll find it is worth it.

JFM is right, if your dealer didn't set up the cartridge for you get a protractor, many are available for free online, and set it up right, or borrow one from your dealer who should have set up the table for you anyway.
 
I have to understand how to better set up this azimuth business....

Do we adjust the azimuth on a JMW9 tonearm via the counterweight or is there another way? I think that I understand the basic concept, but I need to know how to go about with the execution.

JFM - thanks for the tip.... yes, analog is an even bigger pathology than I once envisioned, no kidding. A disease all on it's own.
 
There is an azimuth balance ring around the base of the arm. You have to rotate it to set the azimuth. Check the manual - it is also available online. The best way to set it up is to place the stylus on a small mirror on the platter and look at the reflection. When the cartridge base and the reflection are parallel the azimuth is right.

It is of course possible that you have a cartridge with unequal output from the two channels, or a phono section with unequal gain. Try switching the inputs to the preamp if the azimuth fix does not do it.
 
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VPI instructions regarding the azimuth is not very clear. I guess one would have to be a seasoned vinyl guru to be understand what the scant manual commands.

Risabet and Bernard.... thanks for the tips. So the counterweight is the only way to adjust the azimuth? Risabet says the counterweight is the way to adjust the azimuth..... Bernard, which do you mean by weight at the base of the arm? You mean the counterweight or another means of adjusting the azimuth?

I did play with the counterweight and I did note an improvement in the image (before I left the apt for the 'rents house for the weekend). I have almost centered now, much better than before. The dealer set up the table before it left the shop... shipped it to me and helped with set up over the phone, step-by-step.

I can always call him on Monday for more help (after work). But, I'd rather get some more input from this place because I know there are a lot of vinyl experts here.

Thanks!
 
There is an azimuth balance ring around the base of the arm. You have to rotate it to set the azimuth. Check the manual - it is also available online. The best way to set it up is to place the stylus on a small mirror on the platter and look at the reflection. When the cartridge base and the reflection are parallel the azimuth is right.

It is of course possible that you have a cartridge with unequal output from the two channels, or a phono section with unequal gain. Try switching the inputs to the preamp if the azimuth fix does not do it.

I'm going to try this mirror idea. The cart should be good though, it's a brand new Dyn cart.

I think this is tweaking type of problem... I did "crudely" adjust the counterweight just before I left and I did improve the imaging towards the center.

However, I'm not there yet. The image is still slightly off and a bit weak in terms of weight. If this is all the weight I can get, it's somewhat disappointing.

I'm confident that this is a result of subpar, first-time TT set up by a novice.... er amateur (me).

Thanks so far guys, I think I'm going in the right direction.

More questions:
1. What is the protractor for? I think one was included in the package.
2. Counterweight is the only way to adjust azimuth, right?
3. Best way to adjust the azimuth by a noobie? Mirror idea? What about the coffee stirrer idea on the VPI manual?
4. Is image weight just a function of me getting the image straight and dead center?

Thanks guys, again.
 
Joey, have a look at these pictures...

I don't know if the JM-9 is the same as the JM-10 series in this regard, but, on the JM-10 there is a collar at the bottom of the unipivot tower that has a flat spot towards the front (with the VPI logo on it), some numbers at the top, and a set screw at the side. Using the mirror method Bernard described, or better yet using a protractor, back out the set screw enough that you can rotate this collar to the left or right to adjust the azimuth. Once it's set, tighten up the set screw and your azimuth is dialed in.

Hope this helps...
 

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There is an azimuth balance ring around the base of the arm. You have to rotate it to set the azimuth. Check the manual - it is also available online. The best way to set it up is to place the stylus on a small mirror on the platter and look at the reflection. When the cartridge base and the reflection are parallel the azimuth is right.

It is of course possible that you have a cartridge with unequal output from the two channels, or a phono section with unequal gain. Try switching the inputs to the preamp if the azimuth fix does not do it.

Didn't VPI change from the azimuth ring to using the counterweight with the current generation of JMW 9 arms? I'm almost positive they did. Check this thread on AA.

Welcome to the real world!

http://db.audioasylum.com/cgi/m.mpl?forum=vinyl&n=455195&highlight=jmw+9+azimuth&r=&session=
 
Didn't VPI change from the azimuth ring to using the counterweight with the current generation of JMW 9 arms? I'm almost positive they did. Check this thread on AA.

Welcome to the real world!

http://db.audioasylum.com/cgi/m.mpl?forum=vinyl&n=455195&highlight=jmw+9+azimuth&r=&session=

Welcome to the real world alright.... geez. Good thing I didn't open up the TT setup until yesterday night... I would've not gotten anything done. Good thing for willpower, for once.

Tim,

I don't think the 9 has the exact collar as the 10. I am not at my apt now, but I know there is some sort of a "ribbed" collar around the base of the arm. The counterweight has been my only method of "crudely" adjusting the azimuth... I didn't even know what I really doing, I was only going by basic common sense and adjusted the image sort of back to center serendipitously.

Got some work to do.... better roll up my sleeves.

Can you guys define these terms for me?
VTA
VTF
SRA
Overhang
Zenith
Downforce

Also, someone on another forum told me that if I wanted to, I could ride the tail down a little bit and get a fuller body to the sound?

I love this tweaking!
 
Didn't VPI change from the azimuth ring to using the counterweight with the current generation of JMW 9 arms? I'm almost positive they did. Check this thread on AA................
I was not aware of that. I had a dropped counterweight on my old Formula IV tonearm, and hated it as it was very finicky.

Joey, one thing I forgot to mention is that it is particularly important with a unipivot arm (well, really with all arms) to ensure that the turntable is perfectly level. I always have a small round (1" dia) level on my TT.
 
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...........

Can you guys define these terms for me?
VTA
VTF
SRA
Overhang
Zenith
Downforce

Also, someone on another forum told me that if I wanted to, I could ride the tail down a little bit and get a fuller body to the sound?

I love this tweaking!
Check this link:
http://www.soundfountain.com/amb/ttadjust.html

BTW one check of correct azimuth is the following: at the cartridge reverse the leads of one channel and play a mono record. When you get least output from your speakers at your listening position the azimuth is set correctly. Now if you had an oscilloscope........
 
Joey,
Setting up a TT seems to be an acquired skill. I like it done right so when I bought my first TT I paid someone who knew what they were doing to set it up. Although, I would like to take the time to learn how to do it myself.

You may want to check one the TT setup instructional DVDs that are now available. This one is available from the NeedleDoctor for about $30. Probably a good reference to have on hand while you own the table.

http://www.needledoctor.com/Michael-Fremer-Turntable-Set-Up-DVD

http://www.needledoctor.com/core/media/media.nl?id=9662&c=ACCT106601&h=90932586ad3602af6ce1
 
...........Using the mirror method Bernard described, or better yet using a protractor.........
But the protractor is used to set the overhang, not the azimuth.

BTW when I recently re-setup my TT, I first used the VPI-supplied protractor, which uses the cartridge body for alignment. I then checked it against the Cartalign protractor I bought many years ago and found it completely off. I reset it using the Cartalign, ignoring the VPI, as the Cartalign sets it at two points rather than one, and it is done by aligning the cantilever instead of the cartridge body.

Joey, welcome to the obsessive-compulsive world of turntables. When you get it right, though, it is sooo sweet !!

Are you using your cartridge loaded or unloaded ? :D
 
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Once I have a free moment on Monday afternoon, I'm going to play with the TT and see if I can get it better set up.

Thanks for the tips so far. I will get back once I get going here. I know Dave's got my back too...and the dealer will receive a call if I need it.
 
But the protractor is used to set the overhang, not the azimuth.

BTW when I recently re-setup my TT, I first used the VPI-supplied protractor, which uses the cartridge body for alignment. I then checked it against the Cartalign protractor I bought many years ago and found it completely off. I reset it using the Cartalign, ignoring the VPI, as the Cartalign sets it at two points rather than one, and it is done by aligning the cantilever instead of the cartridge body.

Joey, welcome to the obsessive-compulsive world of turntables. When you get it right, though, it is sooo sweet !!

Are you using your cartridge loaded or unloaded ? :D

Bernard,

You are killing me! Now I need a new protractor... when I don't even know how to use my VPI protractor! LOL!

And how am I to know if my Dynavector is loaded or unloaded? :eek:

I haven't felt this dumb since I got into this hobby.
 
Bernard,

You are killing me! Now I need a new protractor... when I don't even know how to use my VPI protractor! LOL!

And how am I to know if my Dynavector is loaded or unloaded? :eek:

I haven't felt this dumb since I got into this hobby.

Don't excessively load a high output Dynavector, they are designed to run into a > 1 kohm load. I wouldn't even worry about loading until you get the measure of setup, break-in, and listening.
 
I know Dave's got my back too...and the dealer will receive a call if I need it.


All right Joey, PaPa Dave here. Now here's the first step in setting your azimuth on your VPI.....you know that small piece of straight wire about 4-5" long that came with your TT ??? It is to be set perpindicular to the cartridge on top of your headshell and when lowered onto the record (test mule, set/up record), the wire rod is to be parallel to the record surface. this can be measured with your eye or a ruler. Adj countereight accordingly, remember to RECHECK VTF after your done !!

If you want to get really preceise the azimuth can be set with a test record and volt meter(s) to measure the voltage between channels.
Call me if you think your going to try this method and I'll explain it in detail.
 
I'm clueless on TT setup even though I used to own one and planning another analog setup sometime in the near future. For starters, what is cartridge loading?
 
All right Joey, PaPa Dave here. Now here's the first step in setting your azimuth on your VPI.....you know that small piece of straight wire about 4-5" long that came with your TT ??? It is to be set perpindicular to the cartridge on top of your headshell and when lowered onto the record (test mule, set/up record), the wire rod is to be parallel to the record surface. this can be measured with your eye or a ruler. Adj countereight accordingly, remember to RECHECK VTF after your done !!

If you want to get really preceise the azimuth can be set with a test record and volt meter(s) to measure the voltage between channels.
Call me if you think your going to try this method and I'll explain it in detail.

Thanks Pops! I'll double check for this wire and give my dealer a call once I have free time tomorrow PM if I can't find it.

I'm getting a lot of PMs also regarding the setup.... so I got lots to read! I hope to get the majority of the set up tomorrow night. I only have ER orientation tomorrow, and work on Tuesday, Wednesday, and Thursday. If anything, I have Friday to finish up what I can't do tomorrow PM.

*Sigh*... so much to do.

Also, I just began building my own acoustic treatments, much like those by Real Trap. An audiophile's work is never done I guess. :eek:
 
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