Eldartford, do you know I never actually tried to play 78s on my Lencos? I stumbled on them entirely by accident one day, and that particular model being defective, I simply threw out everything which was not directly connected to the drive system, thus accidentally modding it and being blown away by the sound. From there, hooked, I pursued the idler wheel grail. But from perusal of various 78 and mono stylii, I believe these can be tracked today from as low as 2 grams and up to 5. Others with hands-on experience will know more.
While it's true that high mass platters overcome belt reaction to a certain degree, what is actually happening, since physics cannnot simply be banished, is that this mass lowers the frequency of the reaction, as the belt reaction must overcome greater mass/inertia, thus reacting continually, but at a slower pace. This is why high-mass decks sound less lively than lower-mass decks (their bass rhythms messed up by low-frequency reaction), which major in PRaT, versus the information retrieval of high-mass decks which overcomes high-frequency belt reactions. I used to have one of the highest mass platters in the business on my Maplenoll, a 40-pound lead platter. Yes, there was greater retrieval of information, but it also sacrificed the famed Maplenoll liveliness. I eventually went back to the lower-mass Maplenoll Athena, which is far more musical. Thus is the high-mass/low-mass phenomenon exposed, as the human ear is still the best measuring instrument we have, with respect to music. Once I had a good idler wheel properly set-up, I was forced to seek the causes of the great increase in detail, attack, bass, imaging, and so on. So, having experience of both high-mass (Maplenoll Ariadne) and low-mass (Ariston, AR-XA modded, Maplenoll Athena) belt-drive 'tables, I came up with the above theory, which seems to fit the facts. A recent review of the Origin Live Aurora Gold turntable in Stereo Times had the following to say: "The heart of music is time and timing: music unfolds in its own created universe of time, divided into smaller sections placed within that fluid time scheme, divided further down to the individual note. Each individual note begins with silence, rises to its intended volume and then decays. Identifying that note, the instrument playing it and the physical location of it are all based on an exact sequence in time. It wouldnt be too false a metaphor to understand music as an emotional language based on intervals of tone and time."
And what has better speed stability than an idler-wheel drive with perfect wheel, incredible cogless 4-pole 1800-rpm motor, and massive balanced flywheel platter which creates a closed system (groove modulations and stylus drag? what's that?) in which the platter smooths out the motor's revolutions while the motor carries the platter relentlessly? And yes, you're right, this extemely high-torque design is an accident of being designed for high stylus pressures - 5 to 10 grams - in the old days. But properly designed and implemented (a heavy, non-resonant plinth), the extreme speed stability regardless of groove modulations and stylus pressure is entirely audible at 33 1/3 rpm, even compared to the best of belt-drives. Again from the same review: "Since accurate tracking of the timing of a note - its loudness, attack, flowering and decay is also the perceptual mechanism behind reproducing a coherent stereo image, its no surprise that the I/AG is as adept at reproducing the stereo illusion as it is with the music unfolding within that illusion." And here speed stability must be the reason my Lenco with Rega arm clearly out-images and out-soundstages my parallel-tracking Maplenoll (the precursor of the E-T tonearms, the Maplenoll having been designed in part by Bruce Thigpen). To conlude, it's not for nothing that I flipped over the Lencos. A series of accidents beginning with a 'table which was designed to combat extreme stylus drag in the days of 78s, and ending with a lad who already owned a Maplenoll Ariadne and Audiomeca turntable, but in a foreign land needing a table cheap and picking an idler-wheel 'table he had never heard of at a flea market.
