The story of Mind-Pop Revolution record stabilizer with inertial tonearm lift system.
December 11th, 2018
Toulouse, France
Have you ever heard the expression mind-pop? Do you even know what a mind-pop is?
I didn't...
So, one day, about four or five years ago, I was tinkering with an SME series 3 tonearm and I was just not too happy with its complex constitution and the many adjustments required just to set the thing right... and at the end of all that, I thought to myself, it doesn't even get up at the end of the play to offer the decent courtesy to lift my cartridge off the last groove in the vinyl.
And right there, right then, just like that, in that very moment, I saw in my mind this center weight with a spiral groove in it which would beautifully raise the head-shell off the vinyl at the end of the play. It just came, a vision from I don't know where...
Later I learnt that these things are called mind-pops. I found this definition courtesy of dictionary dot com:
mind-pop. [mahynd-pop] noun Psychology Informal. a word, phrase, image, or sound that comes into the mind suddenly and involuntarily and is usually related to a recent experience.
Well, my imagination led me to find a theoretical solution to a need. I thought long and hard about its merit and if it would even be worth the development time. My curiosity persisted to keep my interest alive and I often found myself sketching this thing on scraps of paper, always wondering if it would really work.
Time went by and still once in a blue moon I would think about how cool a record stabilizer with a built-in lift system would look on my turntable. I have a cool collection of cartridges and I was encouraging myself that I would probably be more willing to take the good ones out if I had the luxury of the auto lift at the end. I tend to be absent minded and generally realize much later that in fact the record has been over for a while.
Six years ago, I moved from Ontario, Canada to the south of France with my job. We go back to Canada at least once per year to visit family and friends.
One day in July 2017, during a get-together, I mentioned the idea to my good friend Edy from Toronto who is an accomplished mechanical engineer. We exchanged some details about how this contraption would work and what elements would be important to be taken into consideration. I did not need to do much convincing, he was intrigued and definitely his curiosity was stirred... Edy was convinced we could make this work. We got excited and so, we started to work...
...continued on December 26th, 2018
As soon as I arrived back in France, I already knew how to get going, what the first step would be... I went and bought some clay, found an old record to sacrifice as a work bed, and on a faithful Technics SL-1200, just like a pot-maker, guided by imagination and enthusiasm, I had conceived the first iteration of my vision. Not bad, the first try had some merit... got the job done, one out of five sort of thing...
Meanwhile in Toronto, after an intensive search for features and quality, Edy bought our first 3D printer and while he was eagerly waiting for its arrival, the first model on Solid Works took shape with many improvement features we both believed to be superior over the clay model. As soon as Edy received the printer, he quickly set it up and by the end of August 2017 the first 3D model arrived to my home and I eagerly started putting it through various trials...
It quickly became clear we were closer to the scope with the clay model rather than with the first "improved" version. We were back to square one.
Failure led to persistence: another version followed and another and another. The problem was, we could get it to work most of the time but it would not work consistently; and even 100 out of 100 times was not enough, I wanted to see this thing working without failure 1000 out of 1000 times, no exceptions, no compromise. How could it otherwise be state of the art?
We must have had more than 20 variations in 3D models until we settled on the proper form, proportion and functionality.
It is difficult to envision why the equation becomes complex but it gets rather challenging because of variations between head-shell/cartridge combinations (by height) and their tangential position at the end of play due to arm length and angle, coupled with the different gaps and groove trajectories between the end of the last track and the final groove of the record.
In the span of decades of vinyl record fabrication by various manufacturers, I noticed a number of different configurations at the end of the play and we needed to understand exactly what happens with the stylus after the end of the last tune in all such possible configurations in order to be able to mechanically accommodate a feature capable to pick up the arm at the right moment and lift it properly, without failure, without the need to synchronize anything whatsoever and without having to worry about its position when the stabilizer is placed on the record.
The user experience was the only objective we never dismissed. We wanted this instrument to work with confidence and reliability. After all, we did not want to build an accessory, we wanted to build a dependable tool for the user, the kind of tool you trust without doubt and if you fall asleep all night in your favorite Lazy-Boy, no problem, you have nothing to worry, the cartridge is up and no fuzzy noises go through your amp.
So far I have been focusing on the lifting of the arm aspect, maybe so because this was the original intent but this is not all what this tool is capable of. It is after all a record stabilizer and its scope is to improve the sound extracted from the record.
This is the area where Edy spent time investigating the optimization of mass, benefits, advantages, disadvantages and what happens to a flywheel in rotation when disturbances are introduced in the system. He evaluated in detail what minute elements could be utilized in our design to effectively help minimize the effect of shock, and absorb the reflections generated within the revolving system from external shock. We have collaborated in this investigation and learned a great deal, in fact it is fascinating to contemplate how much there is to learn when you set out on a path to investigate the behavior of a system even as simple as this one.
The amazing conclusion comes when you take the results from your investigation and apply all your knowledge and imagination to innovate, create a solution, an improvement in an effective way, in a way it was never done before.
While I really do not want to dwell into the technical side, here's one thought only to stimulate imagination: if for instance, someone stated that an external shock to a turntable in operation (no matter how rigid the base or heavy the platter) could create an effect described as micro-precession, how would that effect be counterbalanced if the entire mass of the revolving system is spinning?
We have all seen the acrobatics of Chinese spinning plates; when they go badly into precession, the juggler repositions the axis of rotation underneath to eliminate the wobble, speeds up and then re-centers, this is how she keeps them going... but on a turntable in motion, we cannot micro-adjust the absolute center of rotation, then how could it be done? What if we have a free mass in the center that is not in rotation but has the capacity to react in an equal but opposite direction to minimize the effect of micro-precession caused by the external shock?
While it is not all so evident from the models in the picture above, we had put a lot of effort in optimizing the proportion of volume and consequently mass between the fixed parts and the rotating parts in such way that the distribution of mass would benefit and contribute positively to the performance of the entire system.
And then the bearing gave us a lot of trouble... We experimented with more than ten different bearings, from the cheapest on Amazon to aerospace grade. The bearing was a component that needed careful consideration because the relation between its various characteristics proved to be key to the performance of the entire system. We found that ceramic balls are better than steel for this application but we needed more slack between the rotating part and the fixed part so that the reaction in vertical position can be quantified. We finally found a solution, not cheap for a ball-bearing but not as expensive as the space-flight qualified option.
The reality is that there is more to this tool than what is perceived by the eye. We've done a lot of homework and we would like to share this achievement with those who seek the ultimate improvement tool for the performance of their record player.
We started with the objective to create a record weight that could do an additional task: lift the arm at the end of the play to help save the cartridge from unnecessary wear.
First objective accomplished!
We wanted a record weight stabilizer, not a clamp, and we were able to come up with a solution of optimized mass, in other words, any less might be a compromise to function and more would not really add performance, it would only add more weight.
Second objective accomplished!
We aimed to find a way to help minimize the effect of external shock to the revolving system so that the stylus picks up from the micro-grooves in the vinyl only what you want to hear, minimizing external interferences more than any other device in existence.
Third objective accomplished!
The industrialization of this product was another adventure... I will not get into details but one of the machining houses I approached during the development process put it bluntly: "Your spiral has to be machined as if it was a mould, it is not not easy to machine and it takes a lot of time to machine it and this is why our quote is so expensive..." But they were able to do what we wanted so they got to built the first batch... Indeed another subject for another blog.
Gaby Cristian Mindreci
December 26th, 2018 - day after Christmas
Toulouse, France
