Z is equal to twice the mass of the front end of the tonearm at the effective length. L is the effective length (pivot to stylus tip) R is the counter weight distance from the pivot Well, that cannot be described in English, it can only be described in a You do not add aġ/3 or a half - none of it catches here. If you add 1 gram to the tip of the tonearm you do not addġ gram of effective mass to the tonearm No way Jose!. Keeping that in mind it's easier toĪnother misconception is the relationship between 'effective mass' and mass. Relationships are manipulated such that we're left with grams only - but With grams per millimeters per second squared. Mass here - everything is divided by 1000 and so we're actually dealing Here, by the tonearm manufacturers, as a curtsy to the layman.Įffective mass, like any inertia, is measured in Kg/m/s2 (that is Measurement (in metric grams) is a misconception. "So effective mass in not mass - it's inertia! In fact, even the common There is a very good answer to your question in another forum.
Then use a test LP to guesstimate the resonant frequency. One of my friends uses a home-made tonearm with his DL103 which appears to have an eff mass of nearly 50g! (Probably I am exaggerating, but it's mass-ive.) I would suggest just experimenting with added mass at the headshell (and correspondingly re-balancing your tonearm) until you reach an effective mass that seems to be optimal for your cartridge. Doing that ALSO will increase the effective mass of the tonearm, by a factor equal to the square of the change in distance from the pivot to the center of mass of the CW, times the mass of the CW.įrom what I have been able to learn without owning a DL103 or 103R, there is almost no limit to the effective mass that those cartridges might "like". (As you move down the tonearm toward the pivot, the effect of adding mass at any point on effective mass lessens proportionately.) Adding mass to the headshell will also cause you to need to move the counter-weight further back away from the pivot, in order to counter-balance the added mass and achieve the same VTF. Cheers,Īs someone else wrote, adding mass to the headshell most certainly DOES increase the effective mass of the tonearm, by a factor roughly equal to the added mass, in grams. Vinyl Engine gives the green light to resonance frequencies in the 8Hz to 11Hz range.". The general rule I've read is to multiple the 100Hz compliance number by somewhere between 1.5 and 2.0, then use that result as part of the resonance frequency assessment. I also understand, but am not an expert here, that there is no direct translation or conversion formula. Unfortunately many Asian manufacturers rarely publish that info. Japanese, carts to establish their µm/mN compliance figure at 100Hz rather than the 10Hz typically used by the various on-line calcuators and formulas. I'd suggest trying the resonance test tracks on the HIFi News test record before and after any experiment.Īlso, a potential can of worms, but if you are planning this whole concept because of vinylengine calculator results "are you factoring in the tendency for Asian, espec. Headshell weights are usually for use with extremely light cartridges, but that isn't the case with 103R. Even if you proceed with your experiment, you might just find that you don't have enough counterweight on the back of the arm.