The Korf Blog

The inside story: our research, development and opinions

5 June 2019
Headshell Performance — SME 3009
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In this series of articles, we measure the performance of removeable tonearm headshells.

I'd like to mention once again that this study was made possible by a very generous donation. Mr Jam Somasundram, formerly with Pass Labs and now with Cinemag/Reichenbach Engineering, has given us his personal collection of headshells to measure.

Today, the subject is an original headshell from an SME 3009 tonearm. The first of the species, the one that arguably started it all.
Except it didn't. In 1959, when SME introduced a 3009 series of tonearms, this style of headshell was already in use. One year earlier, Ortofon introduced its SPU series of pickups, mounted in a short (A) and long (G) headshells to fit Ortofon's own tonearms. To prevent people from sticking an A headshell into a tonearm designed for G and vice versa, Ortofon gave them incompatible connectors. A's barrel had a locking pin at the bottom, and G's at the top.

SME 3009, with its sliding base, could accommodate both. So SME used a female headshell connector with two slots, top and bottom.
A few months later, SME introduced its own drilled headshell. It was the first universal one, designed to accept most cartridges in the market rather than one specific kind. Looking at those two slots, SME engineers thought: "why don't we put two pins on ours, top and bottom? Two is certainly better than one!" Thus the iconic SME headshell was born.

The Japanese tonearm designers adopted the Ortofon/SME style of headshell connector, but stuck to Ortofon's G specification — one pin at the top only. As far as I know, Jelco is the only exception, using 2 pins in their headshells, SME-style.

The SME headshell is stamped from thin aluminium alloy sheet. It weighs about 6.5 grams without wires, 7.5 grams with them. It's the second-lightest headshell on test after the noname OEM one. I have no way of dating it, but I think it's from the "R" series of SME 3009/II arms.

Interestingly, it has no slots to adjust the horizontal position of the cartridge. In the 3009 family of arms, the adjustment is made by altering the spindle to pivot distance with a sliding base. This makes for very "entertaining" setup, as you'll need a tool to measure said distance, and you'll have to recalculate null points for every adjustment.
Getting an accelerometer to stick while keeping the headshell and the lettering undamaged was a bit of a challenge.

The oscilloscope trace of SME 3009 headshell's IET measurement looks like a cross between SAEC's, Nagaoka AL-703's and Jelco HS-25's traces. There's extended ringing, but most of the strike energy is quicky dissipated.
SME 3009
Jelco HS-25
Well, the spectrogram certainly looks nothing like Nagaoka's:
There's some superficial similarity to SAEC, but the main modes are a lot lower, and there's more energy in the high frequencies:
Isn't is a surprise? Of all the headshells we've tested, SME's spectrogram is perhaps closest to... cast magnesium Jelco HS-25! Ok, Jelco's high frequencies are a lot better controlled, but the main modes look quite similar. Not bad at almost half the weight!
And last but not least, a comparison with the first IET measurement of the same headshell that we made at the end of February:
Some difference, right?

In our initial measurements, the accelerometer output drove the signal conditioner into clipping. That "comb" you see on the left is clipping artifacts. With no clipping, we also get a more detailed high frequency picture.

How about a waterfall chart then?
These low frequency modes ring almost to 300 ms. This is clearly not a high-performance headshell, but for a lightweight stamped sheet one — not bad!

For IET measurement with a Technics EPC-U24 cartridge, we're comparing the SME with a Jelco.

The picture is quite similar to what we saw without the cartridge. SME has more high frequency "hash", and its main mode is lower in frequency. Otherwise it's quite similar.
Given SME 3009's age, simplicity, and minuscule weight, its measured performance is respectable.
In my opinion, this headshell from an SME 3009 tonearm is far from state of the art. Its today's price of $150-200 can only be justified by the collectors and completists.

But given its age, simplicity, and minuscule weight, its measured performance is quite respectable. SME's reputation for quality engineering is intact.
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