advertisement


LP-12 Naim Aro Owners Please Read

LesW said:
There is no such thing in phono cartridges as a 'standard' distance between mounting points and stylus tip. It is for this reason that headshells are furnished with slots so go out a buy a proper tonearm instead of complaining about being locked into some manufacturers mindset.
Click to expand...
Les, why don't we have a standard distance? Just think how much easier things would be. :)
 
Mignun said:
Unfortunately, convenience aside, slotted headshells are not such a good idea from a sound quality point of view (one of the deliberate design choices Naim made that Andy mentions above). I don't think Naim are alone here. SME don't use a slotted headshell, instead allowing you to adjust the position of the base/pivot to accomodate different cartridges. This way you have the benefits of a more rigid headshell but you do lose out at the base.
Click to expand...

Sure Mignun, I appreciate holes rather than slots may give you optimal sound quality - hence Naim chose this. No problem IMO ... as long as Aro owners understand that if they want to maintain the "optimised arm" that Naim designed, they need to use Linn (or Linn-spec, in terms of bolt-hole to stylus distance) cartridges. Because if they use non-Linn spec cartridges, they have "de-optimised" the arm. :)

And as posted by someone earlier, SME may allow you to adjust the position of the pivot to accommodate different cartridges ... but this doesn't allow the change in offset angle required for optimal alignment. :(

Regards,

Andy
 
andyr said:
Sure Mignun, I appreciate holes rather than slots may give you optimal sound quality - hence Naim chose this. No problem IMO ... as long as Aro owners understand that if they want to maintain the "optimised arm" that Naim designed, they need to use Linn (or Linn-spec, in terms of bolt-hole to stylus distance) cartridges. Because if they use non-Linn spec cartridges, they have "de-optimised" the arm. :)

And as posted by someone earlier, SME may allow you to adjust the position of the pivot to accommodate different cartridges ... but this doesn't allow the change in offset angle required for optimal alignment. :(

Regards,

Andy
Click to expand...
Quite so. The SME allows you to get the correct spindle-to-pivot distance for any effective length but you are stuck with their chosen offset angle*. I assume they did a lot of research and came up with an angle that is close to optimum over a wide range of cartridges.

*The true offset angle is the angle between the cartridge's (stylus's) longitudinal axis and the straight line defining the effective length, i.e., pivot-to-stylus, so it changes slightly with stylus-to-bolt hole distance even if you have holes that appear to fix the offset, such as with the Aro and SME.
 
Nik said:
Can't someone here with an Aro measure the cartridge bolt to pivot distance? It must be possible to do that with enough accuracy.
Click to expand...

Looking at this image it looks like the pivot point is very distinct. We already know that the pivot to outer bolt is 224.5mm. A measurement to the midpoint between the two bolts looks like it shouldn't be too difficult.

aro.jpg


That measurement plus the bolt to stylus distance should get you the effective length.

So is it 230.5 - 7 = 223.5mm
230 - 7 = 223 mm
229 - 7 = 222 mm
 
John said:
So how far do you recon your off with your Aro/Keel and 8.5 mm DV cartridge?
Click to expand...

Probably by about a mm, but as I noted before, the combo sounds great (and it is within the recommended range for the Aro).

Br,
Teme
 
Teme said:
Probably by about a mm, but as I noted before, the combo sounds great (and it is within the recommended range for the Aro).

Br,
Teme
Click to expand...
Using 224.5 mm for the distance from pivot to outer cartridge bolt, an offset of 24°, and 8.5 mm for the distance from cartridge mount to stylus tip gives an effective length of 229.49 mm (Cosine Rule). This requires a pivot-to-spindle distance of 211.4 (Baerwald) or 210.9 (Löfgren B).

To get an effective length of 229 exactly (Naim's spec) the mount-to-stylus distance needs to be 7.95.

(All assuming I didn't cock up the trig.)
 
As previously stated, my DV cart sounded awesome on my Aro on LP12, and I never even adjusted it from the position with the previous Troika. (8.5mm DV20x )
 
Nik said:
Using 224.5 mm for the distance from pivot to outer cartridge bolt, an offset of 24°, and 8.5 mm for the distance from cartridge mount to stylus tip gives an effective length of 229.49 mm (Cosine Rule). This requires a pivot-to-spindle distance of 211.4 (Baerwald) or 210.9 (Löfgren B).

To get an effective length of 229 exactly (Naim's spec) the mount-to-stylus distance needs to be 7.95.

(All assuming I didn't cock up the trig.)
Click to expand...

Nik,

What do you get for an effective length when you plug 7mm into your equation?
 
Nik said:
Of course. Why wouldn't they?
Click to expand...
Can't comment about Linn carts (maybe it's the third hole), but carts from the same manufacturer can have different stylus-to-bolt distances. Earlier Lyras were 7.8mm, whereas the current range seem to sport 9.5mm.
 
Teme, SQ, it's not about whether it sounds great - it's about the optimal alignment alignment ... ie. whether you have an accurate Baerwald 'A' alignment (or whichever alignment you choose to use), so it sounds the best it can be. Use a Linn (or Linn-spec) cartridge with your Aro and you are optimised; use a non Linn-spec and you are not.

What's the point of using an arm which was made with certain design features to optimise its sound, if you end up off-alignment with a non Linn-spec cartridge? Just doesn't make sense, IMO. :( Use the cart it was designed for.

Regards,

Andy
 
Andy, I agree entirely, a Linn cart and an Aro in a correctly specified sub-chassis are a match made in heaven. But when faced with the choice of using a brand new Dv20x vs a 14 year old shagged troika.... well...
 
andyr said:
... it's not about whether it sounds great - it's about the optimal alignment alignment ... ie. whether you have an accurate Baerwald 'A' alignment (or whichever alignment you choose to use), so it sounds the best it can be.
Click to expand...
All pivoted arms are sub-optimal. I'd rather have a sub-optimal ARO/Cart that sounds great than an optimal parallel tracker that sounds crap.
 
andyr said:
Teme, SQ, it's not about whether it sounds great - it's about the optimal alignment alignment ... ie. whether you have an accurate Baerwald 'A' alignment (or whichever alignment you choose to use), so it sounds the best it can be.
Click to expand...

Andy, you must be kidding! I've seen a pic of your botched up LP12 that looks horrible to me. No offence, but it does look far from "optimal" as you say. And now you claim that there is only one universal truth to sound quality! As far as I care, sound quality is subjective, not objective.

andyr said:
Use a Linn (or Linn-spec) cartridge with your Aro and you are optimised; use a non Linn-spec and you are not.
Click to expand...

From the posts above it seems to me that the geometry of my Dynavector could actually be better than that of a Linn cart. But regardless of whether or not that is the case, I let my ears be the judge. As Linn says, if it sounds better, it is better. And my deck sounds miles better now than it did with a Linn arm and a Linn cart (which supposedly had the optimal geometry).

andyr said:
What's the point of using an arm which was made with certain design features to optimise its sound, if you end up off-alignment with a non Linn-spec cartridge? Just doesn't make sense, IMO. :( Use the cart it was designed for.
Click to expand...

See above for my response. But your comment also prompts a question from me: What's the point of having an LP12 and then ruining it with an arm that wasn't designed for it and diy a plinth, armboard etc and end up with something that cannot even be tuned properly by the looks of it?

Br,
Teme
 
James said:
All pivoted arms are sub-optimal. I'd rather have a sub-optimal ARO/Cart that sounds great than an optimal parallel tracker that sounds crap.
Click to expand...

Each to their own, James. I'd rather have an arm/cartridge combo that was optimised. :D And as I will probably never give up my LP12, a tangential arm is not an option. :(

Regards,

Andy
 
You must log in or register to reply here.


advertisement


Back
Top