I can help you there, Eldartford. The Lenco can play over a wide variety of speeds because the spindle against which the idler wheel turns is gradually machined from "fat" to "skinny", the idler wheel itself is carried on a sliding support to transport the wheel to any point along the spindle in infinitely variable increments, much like analogue itself versus the chopped-up digital version of music. Quite ingenious, and the reason why the Lencos are the darlings of the 78 crowd.
As to wow, flutter, rumble and speed variations, these are problems which affect belt drives as well, which is why these figures are given out even today. As well, belt-drive motors (cogging 150-300 rpm motors) often exhibit problems, as they are not nearly as well-built as the smoothly-spinning cogless, 4-pole, 1800-rpm idler-wheel motors of yore; belts are rubber bands which constantly react to "stylus drag" every time the needle hits heavily modulated passages (which is why so many belt-drives - even high-end ones - lose it when things get complicated)...all problems which do not affect properly set up idler-wheel drives. Probably why Sugano used a Garrard 301 in designing his Koetsu cartridges. Here I will quote from a very knowledgeable and logical man of open and working mind, Rudolf A. Bruil: "In order to achieve a perfect and steady turning of the record an EMT, a Thorens TD124 and a Garrard 301 and 401 (and also the early Goldring/Lenco) each have a heavy platter, a strong motor and an idler wheel which make the platter turn in a steady fashion, without a trace of slowing down when loud and complex passages suddenly occur. The isolation of the motor should be maximal. The rubber of the idler wheel should be durable and should not transmit motor vibrations to the platter at the same time. The circumference of the idler wheel needs to be impeccable. If this is not the case then rumble, wow and flutter will be the result...In the nineteen seventies several firms started using a heavy platter (6 to 20 kg) with the bulk of its mass concentrated on the periphery in order to achieve extraordinary values for wow, flutter and speed accuracy. If the shaft (spindle) and the bearing are engeneered from the best materials and to close tolerances, the playback of an Lp can give stunning results if arm and cartridge are also of high quality." Lencos with the rubber-covered aluminum idler wheels never have flat spots or other irregularities, the motors and platters are hand-balanced in labs, the platter has much o fits mass concentrated on the periphery, the motors themselves have their own three-point true spring suspension, and the main bearings are excellent. It's all in the execution.
Here is a quote from one of the few comparisons ever made between a modern high-end 'table, a Michell Gyrodec, and a rebuilt idler-wheel drive, the Garrard 401, in Hi Fi World: "I also strongly suspect, after listening to the very clean transient starts and stops supported by this turntable, that its high torque drive system suffers less from dynamic slowing than belt drives. That's why it not only sounds dynamic, but has a very good sense of pace and rhythmic control. The rumble demon has been banished completely by Martin Bastin's new bearing and plinth. Previously it measured around -25dB at 25Hz, relative to the DIN rumble test tone. Now, the spectrum analyser shows 25Hz level measures -60dB, looking like ordinary disc surface noise rather than a discrete rumble component. The smoothness of the rumble spectrum indicates there is no rumble as such."
So, if by recapturing the sound of our youth you mean music played with the proper authority and spot-on timing, which is absolutely crucial to proper reproduction of music and hence musical thrills, then yes, I agree with you entirely.
As to wow, flutter, rumble and speed variations, these are problems which affect belt drives as well, which is why these figures are given out even today. As well, belt-drive motors (cogging 150-300 rpm motors) often exhibit problems, as they are not nearly as well-built as the smoothly-spinning cogless, 4-pole, 1800-rpm idler-wheel motors of yore; belts are rubber bands which constantly react to "stylus drag" every time the needle hits heavily modulated passages (which is why so many belt-drives - even high-end ones - lose it when things get complicated)...all problems which do not affect properly set up idler-wheel drives. Probably why Sugano used a Garrard 301 in designing his Koetsu cartridges. Here I will quote from a very knowledgeable and logical man of open and working mind, Rudolf A. Bruil: "In order to achieve a perfect and steady turning of the record an EMT, a Thorens TD124 and a Garrard 301 and 401 (and also the early Goldring/Lenco) each have a heavy platter, a strong motor and an idler wheel which make the platter turn in a steady fashion, without a trace of slowing down when loud and complex passages suddenly occur. The isolation of the motor should be maximal. The rubber of the idler wheel should be durable and should not transmit motor vibrations to the platter at the same time. The circumference of the idler wheel needs to be impeccable. If this is not the case then rumble, wow and flutter will be the result...In the nineteen seventies several firms started using a heavy platter (6 to 20 kg) with the bulk of its mass concentrated on the periphery in order to achieve extraordinary values for wow, flutter and speed accuracy. If the shaft (spindle) and the bearing are engeneered from the best materials and to close tolerances, the playback of an Lp can give stunning results if arm and cartridge are also of high quality." Lencos with the rubber-covered aluminum idler wheels never have flat spots or other irregularities, the motors and platters are hand-balanced in labs, the platter has much o fits mass concentrated on the periphery, the motors themselves have their own three-point true spring suspension, and the main bearings are excellent. It's all in the execution.
Here is a quote from one of the few comparisons ever made between a modern high-end 'table, a Michell Gyrodec, and a rebuilt idler-wheel drive, the Garrard 401, in Hi Fi World: "I also strongly suspect, after listening to the very clean transient starts and stops supported by this turntable, that its high torque drive system suffers less from dynamic slowing than belt drives. That's why it not only sounds dynamic, but has a very good sense of pace and rhythmic control. The rumble demon has been banished completely by Martin Bastin's new bearing and plinth. Previously it measured around -25dB at 25Hz, relative to the DIN rumble test tone. Now, the spectrum analyser shows 25Hz level measures -60dB, looking like ordinary disc surface noise rather than a discrete rumble component. The smoothness of the rumble spectrum indicates there is no rumble as such."
So, if by recapturing the sound of our youth you mean music played with the proper authority and spot-on timing, which is absolutely crucial to proper reproduction of music and hence musical thrills, then yes, I agree with you entirely.