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ORTOFON SMG 212 cartridge advice

andvinylly

hit that long lunar note
I have used this arm on my 401 for some time but only with MM type cartridges, like Shure MJ 75 and an Ortofon Blue,but recently I tried an old Ortofon MC, a Quattro,that was lying around, it sounds really good, but Im wondering if its OK to run an MC without any anti skate, and has anyone got any experience of other MC and headshell combinations that may work as the Ortofon MC I'm using is already well aged
thanks
 
All cart's, MM, MC or any other principle, require anti-skate on conventional tonearms (that is other than parallel trackers and long - say 11 inch or longer - arms). It is a function of geometry of the arms and friction and all styli experience friction.

Running without anti-skate will do no major harm, apart from lop-sided wear to the groove, but sound very odd.
 
Thats what I thought, but as there seems to be no way of adjusting anti skate, it was missing, plus SPU's track at 4g so sound like they have a good footing in the grooves, sounds very high to me
 
Although SMG-212 was billed as '12-inch Professional Tonearm', this is overall length; its effective length is 9 1/8in with offset angle of 22.7º. These were beautifully engineered to have perfect lateral balance by means of a properly done S-shape (no auxiliary lateral balance weight required), something that was rather novel at the time. The pivot to spindle and overall length/effective length geometry was also purpose engineered such that these were a perfect fit on Thorens TD-124 decks.

Not many tonearms featured any sort of anti-skating bias mechanism at the time, mostly due to the fact that cartridges were yet to be designed for sub-2g tracking force (and higher compliance). The hint here is Ortofon's specified tracking force range of '0 to 10 grams'; with the SPU 'Classic' having a recommended downforce range of 3 - 5g (with 4g being considered as 'safest' in the early days).

Were I considering running one of these tonearms with any modern cartridge (other than a budget MM), I'd rig up a simple thread and weight mechanism, likely using SME parts (bias guide, thread and weight) with a notched outrigger bar from a later Thorens arm (perhaps with some sort of 3D printed end stub clamp arrangement to elevate and hold firm in line above the counterweight).
 
Thanks for that info, looks like its going to be more complicated than I thought, and definitely beyond my technical abilities, I did see some pictures of a modified SMG somewhere on this site, and it certainly did not have any kerb appeal.Am I right in thinking that without adequate anti skate, it would likely cause the cantilever to become skew, with extended use.I hear good reviews of the of SPU cartridges, so that might be the safest option, and just grind my records down
 
Thanks for that info, looks like its going to be more complicated than I thought, and definitely beyond my technical abilities, I did see some pictures of a modified SMG somewhere on this site, and it certainly did not have any kerb appeal.Am I right in thinking that without adequate anti skate, it would likely cause the cantilever to become skew, with extended use.I hear good reviews of the of SPU cartridges, so that might be the safest option, and just grind my records down
Any of the SPU models should be fine WRT cantilever skew, as their compliance is a low 8µm/mN. It is the modern higher compliance types that are likely to skew outwards due to lack of anti-skating bias force. The thing to listen out for is mistracking of the RH channel, as this channel is encoded into the RH groove wall and will subsequently have somewhat less tracking pressure on. Not so much of an issue with cartridges tracking at ≥3g, though.
 
ok, thats clarified a lot thanks,as sometimes I think that the Right channel is a little off ie not as full. sounding as the other, so any cartridge which tracks at less than 3g is not advised, which obviously rules out probably 95% of MC cartridges, so either get an SPU,or ditch the arm, if I want to use better cartridges, are MM type cartridges governed by the same physics
 
are MM type cartridges governed by the same physics

The physics involved in tracking etc. are determined by the design of the suspension and things like stylus design, unaffected by whether a coil or a magnet (or scrap of iron) is on the other end of the cantilever.
 
ok, thats clarified a lot thanks,as sometimes I think that the Right channel is a little off ie not as full. sounding as the other, so any cartridge which tracks at less than 3g is not advised, which obviously rules out probably 95% of MC cartridges, so either get an SPU,or ditch the arm, if I want to use better cartridges, are MM type cartridges governed by the same physics
Presumably your Shure is an M75EJ (light green stylus knob?). Assuming you still have it, an original EJ would withstand higher tracking forces. For both the original and EJ Type 2, Shure specified a rather broad 1.5 - 3g. JICO's standard elliptical replacement (JICO Number: E007454 @ $50.) specifies the same range.

Another, perhaps off the wall, suggestion is the audio-technica AT3600L; yes, the carbon cantilever cheapie with its 0.6mil conical tip. This has an official VTF spec of 3.5g (no range specified, just 3.5g). In practice, these work fine in the 2.5 to 3.5g range. It's compliance will allow it to skew a wee bit, but who cares(?), certainly the conical tip will be fine.
 
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thanks again for all the info and help,Ive just bitten the bullet and gone and bought an SPU,i always thought I could get more out of this combo, than I was getting, if that doesn't work outs will look at a more versatile arm like a jello maybes
 
Trying to connect some phono leads to my arm, the bracket snapped, causing two of the fine tonearm wires to become undone, so I have a couple of queries as to what to next, there has always been an earthing issue on the tonearm, is it possible to fit a proper Cardas plug into this SMG 212,and would a possible rewire devalue the arm in any way
What is the best phono stage for SPU type cartridges, anyone with experience, knowledge of these pickups
 
Trying to connect some phono leads to my arm, the bracket snapped, causing two of the fine tonearm wires to become undone, so I have a couple of queries as to what to next, there has always been an earthing issue on the tonearm, is it possible to fit a proper Cardas plug into this SMG 212,and would a possible rewire devalue the arm in any way
What is the best phono stage for SPU type cartridges, anyone with experience, knowledge of these pickups
Is the bracket that you mentioned a terminal strip to which the internal leads connect to after exiting the bottom end of the arm pillar?

According to the manual, some variants came fitted with a terminal socket within the arm pillar, vs. others having twisted flying leads out the pillar end. Later in the manual they describe how to best connect to a terminal strip within a deck (i.e. such as those fitted to similar vintage decks).

"In case the arm is furnished with a socket for plug-in cables, the wires are internally connected to the socket as shown in Fig. 7."

As to fitting an aftermarket socket, the pillar would appear to be long enough, however you'd need know the internal diameter. I'd also measure the amount of unobstructed depth too. With a circa Ø22mm pillar the usual Cardas male DIN5 may not only fit, but require shimming to fit tightly.

Personally, as the SPU is of very low impedance and, therefore, relatively insensitive to hum induction, I'd stick with a terminal strip and make sure that the tonearm wires are kept twisted until they reach it. This would keep the arm stock, and likely preserve its rarity (then again, I am a purist, so take with a pinch of saline).

For amplification, considering the vintage of the tonearm and intended cartridge, the obvious answer is a step-up transformer. Both SPU Classic and Classic E have a 0.2mV output rating and 2 Ohm internal impedance. Therefore, gain should be in the region of 25 to 30dB and recommend input impedance >=10 Ohm. Naturally, Ortofon's most expensive model ST-80 SE is a perfect match, however, looking closer at the specifications reveals that the next model down ST-70 can be ordered in 'Configuration B', ideally matching SPU Classic (or any MC with <10 Ohm coil impedance) and requiring circa 30dB gain.
 
Seems like you sort one problem out,just to uncover another, the wiring should be easily sorted, but laying out big bucks for an SUT could be a challenge at present, are there other comparable SUT's that I should look out for,or am I just a dreamer
 
I've an Ortofon STM-72 here that is compatible with coils of 2-3 Ohm. IIRC, gain is circa 35dB with this one. These in-line type used to be as cheap as chips, don't know what they go for nowadays.

I also have a 2-15K model here which is more or less the same thing in a plastic package, the contents of which are essentially what Ortofon soldered onto the pins of the original SPU-GT.
 
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ok, I've got an STM 72 and a MCA 76,infact thats how I came to break the the phono sockets, trying to put a smaller leads in,as the D102's plugs were too broad for the STM-72,so that could work, just be slightly hotter than neccesary,the other problem is that the phono stage can easily clip the line level on my Meridian 562v,which is set to a max of 2.5v sensitivity at present, not sure analogue can fit in with DSP speakers
 


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