AT OC9 Set up advice please.

[Natara]

AT OC9 Set up advice please.
Usually I get my dealer to set up and align any newly acquired cartridges but flush with success after changing tone arm cables I have decided to have a go myself and would be very grateful for any help and advice. Cart is Audio Technica OC9 tone arm is a Linn Ittok and deck is LP12 and please remember I'm a complete novice.
:scratch::scratch::scratch:
Kindest Regards

[RothwellAudio]

There's a lot of information and some downloadable alignment protractors here
http://www.vinylengine.com/tools.shtml
There's more than one alignment geometry possible but getting the cartridge into the headshell with the "right" overhang is critical. But as I said, there are different versions of "right" :scratch:
Then just set the tracking force and the height of the tonearm (if possible) to set the vertical tracking angle (VTA).
Just do a bit of reading first to gain some confidence.

[Barry]

There's a lot of information and some downloadable alignment protractors here
http://www.vinylengine.com/tools.shtml
There's more than one alignment geometry possible but getting the cartridge into the headshell with the "right" overhang is critical. But as I said, there are different versions of "right" :scratch:
Then just set the tracking force and the height of the tonearm (if possible) to set the vertical tracking angle (VTA).
Just do a bit of reading first to gain some confidence.

Not true. There is only one optimum alignment geometry for a given arm - and that is determined by the design of the arm. Even that, whilst 'optimum' for the arm/cartridge combination, may not be one which achieves the lowest tracking distortion.

[RothwellAudio]

Not true? How so? This is my understanding of the topic:

There are only two variables to play with - the first being the distance of the stylus from the pivot, and the second being the offset angle between the cartridge body and the line passing through the pivot and stylus. Calculations of the various possibilities have been made by Baerwald, Loefgren and Stevenson and they came up with similar but slightly different geometries to achieve the best performance averaged over the playing length of a disc.
If your tonearm and headshell offer enough scope to move the cartridge backwards and forwards by a few millimeters and alter the cartridge angle by a few degrees it is possible to choose whichever alignment you want.
A particular arm confines you to a particular alignment only if you want to keep the cartridge parallel/square to the headshell sides. If you don't mind the cartridge looking wonky you're free to choose a different alignment.

If I have misunderstood the topic please feel free to point out the error in my logic.

[mac72]

Not true? How so? This is my understanding of the topic:

There are only two variables to play with - the first being the distance of the stylus from the pivot, and the second being the offset angle between the cartridge body and the line passing through the pivot and stylus. Calculations of the various possibilities have been made by Baerwald, Loefgren and Stevenson and they came up with similar but slightly different geometries to achieve the best performance averaged over the playing length of a disc.
If your tonearm and headshell offer enough scope to move the cartridge backwards and forwards by a few millimeters and alter the cartridge angle by a few degrees it is possible to choose whichever alignment you want.
A particular arm confines you to a particular alignment only if you want to keep the cartridge parallel/square to the headshell sides. If you don't mind the cartridge looking wonky you're free to choose a different alignment.

If I have misunderstood the topic please feel free to point out the error in my logic.

I'd say you're spot on , as long as headshell allows for it we can choose which geometry suits our preferences/music we listen to ,
We can choose between:
Baerwald - same level of distortion at the beginning and the end of the record, the peak between the null points

Loefgren -minimises average distortion across a side (in practical terms it means a bit more at the beginning and end, but less in the middle).

Stevenson gives pretty much zero distortion at end of side, this is at the expense of slightly higher mid point and start of the record distortion than either Loefgren or Baerwald,
Obviously there are others but most of them are just slight variations of mentioned earlier , which one to choose is entirely up to you , Baerwald seems to be frequently used , Rega uses null points close to Stevenson , VPI geometry is close to Löfgren’s I think and so on...

[Barry]

Arm manufacturers design their arms to have a specific offset angle and a specific overhang of the stylus relative to the turntable spigot. In many cases these values are not commensurate with those following one of the preferred geometries: Baerwald; Loefgren or Stevenson.

Quite often the arm/cartridge alignment can be made to correspond to one of the above geometries if the cartridge is skewed in the headshell, but that is not how the arm designer intended the arm to be used.

http://theartofsound.net/forum/showthread.php?20109-Tonearm-alignment

[karma67]

Arm manufacturers design their arms to have a specific offset angle and a specific overhang of the stylus relative to the turntable spigot. In many cases these values are not commensurate with those following one of the preferred geometries: Baerwald; Loefgren or Stevenson.

Quite often the arm/cartridge alignment can be made to correspond to one of the above geometries if the cartridge is skewed in the headshell, but that is not how the arm designer intended the arm to be used.

http://theartofsound.net/forum/showthread.php?20109-Tonearm-alignment

try and remember the op is a novice,
to the op setting up your ittok using Baerwald alignment will be absolutely fine.
if you get really stuck try audio t in london rd brighton,they will set it up for you :)

[RothwellAudio]

try and remember the op is a novice,


Yes, absolutely. I was trying to avoid too much confusion in my first post - but probably failed miserably :doh:
Yes, simply having the cartridge sitting straight and square in the headshell and using the tonearm manufacturer's recommended overhang should be fine.

BTW, that's a good link from Barry. I haven't found my way round the site properly yet and didn't realise that there was such a useful page available on the site.

[Barry]

try and remember the op is a novice,
to the op setting up your ittok using Baerwald alignment will be absolutely fine.
if you get really stuck try audio t in london rd brighton,they will set it up for you :)

Point taken. :o

Looking at the data for the Linn Ittok on vinylengine.com, the two null radii for this arm are at 65.7mm and 120.6mm, therefore the use of any standard alignment protractor corresponding to the Baerwald geometry will be fine.

[Natara]

try and remember the op is a novice,
to the op setting up your ittok using Baerwald alignment will be absolutely fine.
if you get really stuck try audio t in london rd brighton,they will set it up for you :)

Thanks for all your help and advice. After a few trials and tribulations and a loose gartridge tag that wouldn't play ball the deck did end up back in Johns (Audio T) more than capable hands and again he was a true gent. I have had the deck back a week or so now and I'm really loving what the AT OC9 does, quite different from the 10x5 I had before, when it likes a recording it sounds great but give it something not so well recorded and it's not so great. The 10x5 would play anything I threw at it very well but didn't really excel at anything the way the AT OC9 can, listening to Bob Marley's Exodus LP I heard percussion instruments that in 30 years I hadn't heard before. I have heard the AT OC9 described as being too HiFi or too bright but in my system it sounds excellent, I will be looking to be a brand new cart next year and the AT's are high on the list.

[bob4333]

If you like the AT sound put the AT33 PTGII on your list for a listen.

I have them both and it's the PTG I keep going back to (in preference to some carts costing maybe 3 times the price). Bigger soundstage, deeper and tighter bass and a very detailed top end without being "squeally" (spell check's just gone nuts)

And a bit of an apology - if you had to take your deck to the dealer after asking for help here I feel we let you down somewhat. And I include myself in this - didn't even reply.:o

Saw your question and assumed "someone else'll sort that". :doh:

Try harder next time.

[Floyddroid]

Of all the cartridges I have owned the OC9 still remains one of the very best. Unlike the scientists here I never found the cartridge fussy to set up. Very musical device in my opinion which I preferred to my Lyra Delos.

[Natara]

Bob the fault was all mine the advice I got from here was first rate and I took it all in unfortunately my fingers just wouldn't do as they were told. Yes the AT33's are also on my list I have heard and read lots of good things about them and they can still be had for under 400 quid brand new.