2 mm = 20 minutes [Archive] - Audio & Video Forums

PDA

View Full Version : 2 mm = 20 minutes



02audionoob
07-26-2010, 05:02 PM
I've spent the last 20 minutes fiddling with the alignment of my cartridge and have now settled on a spot 2 mm forward from the previous spot. 2 mm! That's like 8 feet in golf. I don't know how I got as close as I did at the previous position, but I was hearing a tiny of bit of distortion in the first track of some LPs. I just had to try to figure it out. So far so good.

Before...

http://farm5.static.flickr.com/4077/4802275114_695a834d46.jpg

After...

http://farm5.static.flickr.com/4147/4832859612_c8d24f1d8e.jpg

poppachubby
07-27-2010, 01:59 AM
First of all, welcome to AR. Oh 02audionoob! Right, I remember you.

You're sure it was groove distortion and not surface noise? Even a super clean LP will have a bit of noise from the run-in on into the first track, occasionaly.

Alignment is a funny thing. Have you ever mounted your cart, visually set it in place and been 98% correct? The harder you try the worse the fight is.

Your first pic looks damn near perfect.

JohnMichael
07-27-2010, 02:24 AM
In all my years of using a Rega arm and various cartridge alignment guages I have never had the cartridge parallel to the headshell. The Mobile Fidelity GeoDisc has been a long term favorite and using it correctly has the cartridge forward and at an angle compared to the Rega alignment. The Rega arm is set so you have the lowest distortion in the innermost grooves instead of two null points for minimal distortion accross the entire record. Do not be surprised if you find the best sound is with the cartridge forward in the headshell and angled in so the cartridge is not parallel.

JohnMichael
07-27-2010, 03:12 AM
I should have mentioned that since the Rega arm is designed for the Rega alignment the standard two point guages are difficult to use since they tend to assume the cartridge will be parallel to the headshell. Using the Mo Fi one point guage which is designed to give the two Baerwald null points you are setting overhang and offset angle at the same time. Once set up this way your arm will trace the record with less distortion overall.

02audionoob
07-27-2010, 09:35 AM
I'm thinking this battle is not quite over. I feel certain I got much closer with this move. I knew going in that the Shure protractor was based on Baerwald, so the cartridge should have been forward of Rega's alignment, not back toward the middle. Hearing from JM that his is forward and turned makes me want to take another shot at it. Maybe I'll consider one of the MoFi discs, too...wondering if they ever turn up on the used market. Edit...I see they're not that expensive new.

JohnMichael
07-27-2010, 11:23 AM
Here is a link to a tweak that jrhymeammo first posted.

http://www.tnt-audio.com/accessories/schon_e.html

The idea of using the pencil lead taped to the cartridge has helped so much in the aligning of the cartridge. I find it very helpful with the black Mo Fi Geodisc. Oh and one thing about the Geodisc is that it is universal with pivoting tonearms. Once you buy one it can be used with other tables or to help friends set up their tables. I have had mine over 30 years now. Indestructible.

jrhymeammo
07-28-2010, 07:45 AM
The pencil lead tweak is the best if you have a cartridge with sqaure body.
It should be possible with your Goldring as well, but may not be as easy as other carts.

Here is the protractor that I use now until I decide which overpriced laser etched unit to buy... If accessible, it'll be best to print on thick cardboard like paper.

http://www.conradhoffman.com/TemplateGen.zip

Have Fun,
JRA

JoeE SP9
07-28-2010, 08:39 AM
I've been using a DB Systems protractor since the early 80's. It's easy to use (sort of) and very durable. It has some extra grids and radial markings that help with determining which way to move or twist the cartridge to get it positioned correctly.

JohnMichael
07-28-2010, 10:36 AM
I like the speed of set up with the Mo Fi. Once the disc is sighted with the pivot you slide the cartridge so the stylus is resting in the dimple of the Geodisc. You now have overhang set correctly. Next a slight twist of the cartridge so it is parallel with the grid. Recheck overhang, tighten the screws and nuts and enjoy.

JohnMichael
07-28-2010, 07:58 PM
Here is a link to another well respected one point alignment guage.

http://www.musicdirect.com/product/73304

The Mo Fi Geodisc is a slightly better deal.

I also tried the mirrored Turntable Basics guage but the slots for the cartridge were not long enough to align using that guage. I wonder if that is for the Lofgren specs.