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magoorty
22-02-2013, 10:16
Hi all,

I have an AT LH18 headshell which I've been planning on fitting to my 1210 for a while now. I've only just realised that it's too heavy for the arm to balance, even with the technics sub-weight. Has anyone had this problem and found a more elegant solution than blu-tak and a coin? It could do with a fair bit of beefing up. One deck is fitted with a sumiko headshell and nagaoko mp110. These come in together at 18gms. The AT headshell weighs that alone, so with the 2m red I want to use (7gms), I guess I need another 7gms on the back.
Would appreciate any thoughts.

Cheers

OneyedK
22-02-2013, 10:34
The AT headshell weighs that alone, so with the 2m red I want to use (7gms), I guess I need another 7gms on the back.
Would appreciate any thoughts.
:eek: That much effective weight and a 2M red?! :scratch:

I glued a strip of bitumen around the counterweight. Looks pretty good and is enough for the LH-18.

DSJR
22-02-2013, 10:41
Watch the bass reproduction with the heavy headshell and 2M Red and also get yourself a decent stylus balance, since altering the mass of the counterweight will screw up the accuracy of its scale.

magoorty
22-02-2013, 11:27
So would I be best just putting the 2m red on a lighter headshell, or just the technics one? I assumed I'd be better with the AT but if it'll lead to too much bass, I won't bother. What's the reasoning if it's tracking at the correct weight?
Is that what 'compliance' is all about? As you can tell, I don't have a scooby.

Cheers

OneyedK
22-02-2013, 13:25
So would I be best just putting the 2m red on a lighter headshell, or just the technics one?
The Technics one is fine, but if you like, a headshell weighting up to 10-12g will also be fine.

The theory behind resonance frequency, total effective mass and compliance is explained here:
http://www.ortofon.com/support/cartridgetonearm-resonance-frequency

My personal experience with medium-high compliance cartridges is that they don't respond well to higher effective mass.
My AT-OC9ML/II doesn't even sound good with the stock headshell in the Technics.
Don't know the exact reason, but I suppose the suspension is not only softer, but also less strong.
So with higher effective weight, the cantilever will wobble all over the place, making accurate tracking impossible.

magoorty
22-02-2013, 14:01
Thanks for that. That's very helpful. I guess I'd be best to put the 2m on my Sumiko headshell then.
What about the Nagaoka mp110? Would that suit the AT shell? Or am I best to forget about using the AT on the technics at all?

Cheers

OneyedK
22-02-2013, 14:09
Or am I best to forget about using the AT on the technics at all?
It's a perfect match for a low compliance cart like the Denon 103.
But too heavy voor most (if not all) MM cartridges.

DSJR
22-02-2013, 15:57
The 2M Red should be fine in the stock light-weight (but pretty rigid) Techie headshell. You could put some posh headshell wires on though to jazz it up a bit and you may find a subtle audio improvement too ;)

Funk Firm's Arthur has something to say about effective mass of tonearms, since his current take on arm-pipe material is for a very low mass, BUT non-resonant material and construction. The techie arm may not be best for Denon 103's or SPU's etc, but for fixed coil cartridges of recent years should be absolutely fine I think. You'll have a far bigger improvement methinks with a replacement exit cable to the amp than farting around with headshells at present. Save the AT shell for summat really serious :)

prestonchipfryer
22-02-2013, 16:21
Yes Dave is right re the stock Technics HS with the Ortofon 2M. Carefully cleaning of cartridge pins should also give a small improvement. Use caig deoxit or kontak, even isopropyl alcohol. Use sparingly.

John