Need help figuring out cartridge matching
- Thread starter ziggurcat
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tnsilver
Stereo Puppy
Effective mass is not the accumulated mass - it's the total moment of inertia. It's one thing when owners get the concept wrong - but totally different and far more severe when the manufacturer appears ignorant of the concept. Forget the email to Fluance. They just appear to feed on the data from the off-the-shelf tonearm mfgr which doesn't seem to understand the concept either. It's a shame really.
FWIW I've discussed eff. mass many times before (also here) and even how eff. mass is calculated and there are tons of discussions on AK.
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What information would you use to determine whether you multiply by 1.5, 1.9 or anything in between?
Blue Shadow
Waiting for Vintage Gear from this century
You would use a resonance evaluation band on a test record and a known effective mass tonearm.
Since the use of an arm cartridge combination that has an exact resonance frequency is not at all necessary for great phono reproduction, to the extent that ak has gone waaaayyyy overboard on 'finding the right match' I just use about 1.8 and call it a day. I use undamped unipivot tonearms that are designed to work extremely well with a wide range of cartridges and don't really worry about the resonance frequency if my calculations with the VE chart give me something from about 6 to about 12. I don't seem to have any cartridges that yield high resonance frequencies.
Since the use of an arm cartridge combination that has an exact resonance frequency is not at all necessary for great phono reproduction, to the extent that ak has gone waaaayyyy overboard on 'finding the right match' I just use about 1.8 and call it a day. I use undamped unipivot tonearms that are designed to work extremely well with a wide range of cartridges and don't really worry about the resonance frequency if my calculations with the VE chart give me something from about 6 to about 12. I don't seem to have any cartridges that yield high resonance frequencies.
tnsilver
Stereo Puppy
Many prefer the multiplier range of 1.5 - 2.2 and every Tom, Dick and Harry comes up with their own range - depends on their favorite turntable forum. It's thought (not w/o good reason) to depend on the recommended VTF. Higher VTF, as expected with lower compliance carts, means a lower multiplier. Basically... It's a guesstimation that may not be reliable. According to some accounts this method fails miserably with Nagaoka MP carts - reported way more compliant than this method predicts. OTOH, it appears right on the money with the Denon DL-103. There's no accurate formula to convert cu at 100Hz to cu at 10Hz.
808_state
Super Member
So based on your formula listed in the other thread: "The final formula for eff. mass in weight units (grams) is:
M = [m*(r²/L²)] + [Z/3]"
with "r" being the distance from the pivot to the center of the counter weight and assuming your tonearm has the capability of sliding back and forth on the barrel (mine do) with which it screws on the back of the tonearm, one could actually adjust the effective mass of the arm to better dial in a given cart (aside from the normal back or forth to adjust VTF). Within the limitations of the tonearm structure itself and cart mass you could therefore plug in the effective mass you want (based on optimal resonance frequency) and solve for "r".
I'm searching for a test record, but also don't really want to have to spend $100-200 on one (which is the running price just about everywhere I've searched).
Yeah, it seems rather arbitrary, and very easy to just fudge the numbers in order to shoehorn a cartridge into range by just using a lower multiplier. One cartridge I've looked at is the Sumiko Olympia - I've read in several places that it's a low compliance cartridge, but if I do the math, it's telling me that it's a moderate to high compliance cartridge, so I don't know what to believe.
My understanding is that due to the high effective mass spec of my TTs tonearm, I sort of need to have a low compliance cartridge (the logic is telling me the higher the effective mass, the lower the cartridge compliance). And based on the calculator posted earlier, it seems that a cartridge that's around 10-12cu is what I should be looking for (pushing 13 if the cartridge weight is low enough).
I've also read that the US cites static compliance as the spec for their cartridges, and that you should halve that number to figure out the math. Also Ortofon indicates 20 dynamic/lateral in their spec sheet 2M Blue, which doesn't make it clear whether they're citing dynamic or static (assuming lateral and static are the same thing, just using a different naming convention?). Mathematically, the Ortofon shouldn't be compatible, but I've not had any trouble (nor would I really know what to listen for seeing as I have next to no real knowledge at this point).
Oh, I've come to find out real quick that it's not reliable
I have even thought of just using whatever the recommended TF setting is for the cart to use as the multiplier for the Japanese-based cartridges. It's arbitrary, but I think it would be at least somewhere in the close enough ballpark. Oddly enough, it's the Nagaoka carts (MP-110/150/200) that fit within a reasonable range, whether I use 1.5 or 2.2 as the multiplier.
ConfuciusSay
Active Member
I’ll reiterate what I said before - ignore what the manufacturer thinks and go with what seems like a match based on the 2M (i.e. similar compliance to what they put on there in the first place). Even Jelco which is/was fairly well respected always had weird mass numbers posted - you never know what went into their equation or who got a hold of that number on the way to the IT guy who typed it in online.
In my opinion it would be better to spend money on 2 carts at your price range and sell the one you don’t like than to buy a test record.
In my opinion it would be better to spend money on 2 carts at your price range and sell the one you don’t like than to buy a test record.
This is the crux of the problem. There is no direct conversion between static and dynamic compliance so an arbitrary factor is used.
Yeah, I mean I think you're right with this. I have a tendency to over think things sometimes, and I'm certainly skirting that territory.
Blue Shadow
Waiting for Vintage Gear from this century
the range is not a panacea, it is a recommendation. The best sounding nail in my rig has a calculated resonance of 6.5Hz well below the ideal 8Hz. It is a tool to use, it can be used in different ways to accomplish the goal of getting the best sound from a record. Do not let all the matching things up take away the goal of getting gear to sound good together. Like the folks that proclaim Dahlquist DQ-10 must have 200watts of solid state power. I've got some well regarded ss power in that range the 50 watt tube amps sound so much better. Listen and decide. Just cause something is out of range doesn't mean it isn't going to work.
tnsilver
Stereo Puppy
No. Forget the dimwit specs. The Chinese had been knocking off Technics tonearms for so long the low end budget TT makers can't even imagine what a high effective mass tonearm looks like. Your TA effective mass is anything between 12.5 grams to 15 grams tops.
Shure is using static compliance exclusively - it's their policy. Stan/Pick uses dynamic in most official publications and Ortofon always used dynamic compliance. The 2M Blue is a perfect match for your tonearm. The Sumiko Olympia has 12cu@100Hz and 1.8g - 2.2g recommended VTF. If you take the lower boundary for this relatively high range and use 1.8 as the multiplier, you get 21.6cu@10Hz, which is not far from the 2M Blue 20cu dynamic compliance. You'd be in the borderline green zone of 7Hz to 8Hz RF, even by vinyl engine's strict RF calculator.
That's wonderful info, thanks!
ETI_5000
Super Member
Given that the chances are that the tonearm tubing for a Chinese-made arm isn’t exactly the same in thickness and material as the Technics tonearm (independently measured at 13g on the SL-1500, with headshell), I’d widen that suggested range of its possible effective mass up to around 20g. Although it is possible for s-shaped tonearms to have effective masses above 30g, it was often only those with stainless steel arm tubes (e.g. Fidelity Research FR-54S, 35g). More typically most Japanese models are between 10 and 20g effective mass, with some being slightly heavier – JVC QL-F6 21g, Pioneer PL-400 22g, both measured complete with original headshells.
A cartridge with a tracking force of around 2g ± 0.3g should be a reasonable match with that, I’d expect. Forget compliance, although it is related to tracking force – it’s much easier to talk in terms of the ideal (recommended) tracking force, which for the 2M Blue (1.8g recommended) should be OK as a match, if perhaps around or just below the low end of the good resonance range (8Hz) if the arm effective mass is close to 20g. Measured resonances for the 2M Blue with three different tonearms were:
11.2g effective mass (Rega RB-1000): resonance 9Hz
12g effective mass: 10Hz
13g effective mass: 9.7Hz
For the 2M Red (same compliance and tracking force), measured values were:
11.2g effective mass (Rega RB-1000): 9Hz
13g effective mass: 10.3Hz
So it seems that 12-13g is the ideal effective mass for a perfect match with the Ortofon 2M Red and Blue (and Silver).
A cartridge with a tracking force of around 2g ± 0.3g should be a reasonable match with that, I’d expect. Forget compliance, although it is related to tracking force – it’s much easier to talk in terms of the ideal (recommended) tracking force, which for the 2M Blue (1.8g recommended) should be OK as a match, if perhaps around or just below the low end of the good resonance range (8Hz) if the arm effective mass is close to 20g. Measured resonances for the 2M Blue with three different tonearms were:
11.2g effective mass (Rega RB-1000): resonance 9Hz
12g effective mass: 10Hz
13g effective mass: 9.7Hz
For the 2M Red (same compliance and tracking force), measured values were:
11.2g effective mass (Rega RB-1000): 9Hz
13g effective mass: 10.3Hz
So it seems that 12-13g is the ideal effective mass for a perfect match with the Ortofon 2M Red and Blue (and Silver).
tabarddn51
Super Member
It is very rare for a tone-arm to have that high an Effective mass & by looking at the deck & arm I doubt that figure is correct. It is not hard to get a good ''guesstimate'' of the Effective mass. Just take off the cartridge and end weight & measure it with your stylus scales.
However if it is correct the cartridge to get would be a Denon 103, but you will need a MC input.
Cheers
However if it is correct the cartridge to get would be a Denon 103, but you will need a MC input.
Cheers
Yeah, I mean I sort of doubt that they'd mismatch the tone arm and cartridge that egregiously. When I have the energy to take things apart, and fuss around with re-calibrating everything, I'll weigh the arm to get at least a more accurate number from Fluance's specs sheet.
