dŵr & Friends (how not to build a turntable).
- Thread starter InSides
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InSides
dŵr
By all means. I currently use two iOS applications via a calibrated iPhone X - VibSensor and Vibroscope. The graphs I post are straight out of VibSensor, which allows, following a one-time fee, that raw data is exported for further processing.
Actually been looking into using ARTA in conjunction with integrated accelerometers, but haven't gotten around to it.
That is very kind - much appreciated.
Many thanks.
Many thanks - I would love to hear further opinions, of course - but it is virtually impossible since any reviewer would want it in their home, and the logistics of this monstrosity being shipped anywhere are just too cost-prohibitive.
InSides
dŵr
We had some rain lately. Meaning, temperatures go down. Meaning, some work can be done.
To take you a few pages back, when I completed the "new" motor pod, I also did a so called vanity motor cover, in the vein of Micro Seiki, to ensure that mounting screws, pulleys, and belt flex remain hidden, so that the visual focus is locked to the platter rotating. What that looked like, in more detail, can be ascertained here:
However, due to rim drive implementation, I had to (1) make a new pulley and (2) add a new, smaller belt with a lower transfer ratio, leading to a narrower belt flex angle. A direct result of said changes is that the current motor cover is practically unusable. Furthermore, the rim drive additionally helps reduce visual distractions by eliminating the belt around the platter, so the missing motor cover irritated me immensely (first world problems, I know).
To aid you from having to scroll through earlier posts, here is what the rim drive looked like without said motor cover:
Unlike the existing motor cover, I decided to go the way of POM as opposed to aluminium. Apart from deciding that white POM matches the rest of the turntable aesthetically (by adding proper contrast), a more important reason is the minor problem I experienced with the earlier motor cover, as described here (The aluminium cover acted as a horn and amplified the pulley noise to the point of bother during quiet passages). POM has a different damping range, so that issue should be, at the very least, decreased.
Once machining has been completed, the new cover looks suspiciosly similar to an ashtray:
Yet after being put in place, the world is now at peace:
There is no inherent noise due to the cover, no added vibration due to the soft coupling, and the eye sore is gone, so there is that.
Onwards and upwards.
To take you a few pages back, when I completed the "new" motor pod, I also did a so called vanity motor cover, in the vein of Micro Seiki, to ensure that mounting screws, pulleys, and belt flex remain hidden, so that the visual focus is locked to the platter rotating. What that looked like, in more detail, can be ascertained here:
However, due to rim drive implementation, I had to (1) make a new pulley and (2) add a new, smaller belt with a lower transfer ratio, leading to a narrower belt flex angle. A direct result of said changes is that the current motor cover is practically unusable. Furthermore, the rim drive additionally helps reduce visual distractions by eliminating the belt around the platter, so the missing motor cover irritated me immensely (first world problems, I know).
To aid you from having to scroll through earlier posts, here is what the rim drive looked like without said motor cover:
Unlike the existing motor cover, I decided to go the way of POM as opposed to aluminium. Apart from deciding that white POM matches the rest of the turntable aesthetically (by adding proper contrast), a more important reason is the minor problem I experienced with the earlier motor cover, as described here (The aluminium cover acted as a horn and amplified the pulley noise to the point of bother during quiet passages). POM has a different damping range, so that issue should be, at the very least, decreased.
Once machining has been completed, the new cover looks suspiciosly similar to an ashtray:
Yet after being put in place, the world is now at peace:
There is no inherent noise due to the cover, no added vibration due to the soft coupling, and the eye sore is gone, so there is that.
Onwards and upwards.
GruntPuppy
pfm Member
I am in awe. This is superb.
InSides
dŵr
Wow, almost a year since I haven't updated this. I kind of promised myself I would settle down and just listen to the music...
...but had to do some (albeit not very complicated) work.
I changed the "pucks" under the feet of both the turntable and the electronics box to this "new" design. Originally, had aluminium (6082) pucks with integrated Si3N4 ceramic balls (8mm diameter) in a triangular fashion to simulate a kinematic bearing.
These new designs actually consist of two halves, machined from POM (Delrin) housing free-running ceramic balls. Each "puck" has 5 loose ceramic balls (4mm diameter) in a circular recess.
Now, was it worth it to replace the previous design seeing that the system was quite impervious to vibrations? If I was buying them at audiophile prices, I would honestly have to say no. There may be some audible deadening when doing the "knock test", if knocking on turntables is your thing.
But, and there is always a bit, working on the turntable did give me further ideas on possible cosmetic and/or functional upgrades. To that effect:
...but had to do some (albeit not very complicated) work.
I changed the "pucks" under the feet of both the turntable and the electronics box to this "new" design. Originally, had aluminium (6082) pucks with integrated Si3N4 ceramic balls (8mm diameter) in a triangular fashion to simulate a kinematic bearing.
These new designs actually consist of two halves, machined from POM (Delrin) housing free-running ceramic balls. Each "puck" has 5 loose ceramic balls (4mm diameter) in a circular recess.
Now, was it worth it to replace the previous design seeing that the system was quite impervious to vibrations? If I was buying them at audiophile prices, I would honestly have to say no. There may be some audible deadening when doing the "knock test", if knocking on turntables is your thing.
But, and there is always a bit, working on the turntable did give me further ideas on possible cosmetic and/or functional upgrades. To that effect:
- I am having all bronze parts (sans the two full bronze bearings) nickel-plated (matt surface). I liked how a few samples turned out having them sandblasted, then nickel plated - and also, the TiN plating is not holding up with age;
- I came across (OK, fine, I ordered) a block of 6082 alloy with dimensions 340mm x 340mm x 110mm which may lend itself to a radicaly redesigned platter.
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InSides
dŵr
Much appreciated @eguth.
I still dabble in the conventional, especially due to the fact that a record reproduction sub-system needs to fit in with other components in a standard audio system. I am nowhere near the skill required to tackle, for example, the business end of a tonearm (whether it be a coil cartridge or anything else).
There are avenues I would still like to very much research, but I am holding back due to (mostly) lack of time and (mainly) restrictions by my significant other ("there shall be no air compressors anywhere in the home unless absolutely silent").
I still dabble in the conventional, especially due to the fact that a record reproduction sub-system needs to fit in with other components in a standard audio system. I am nowhere near the skill required to tackle, for example, the business end of a tonearm (whether it be a coil cartridge or anything else).
There are avenues I would still like to very much research, but I am holding back due to (mostly) lack of time and (mainly) restrictions by my significant other ("there shall be no air compressors anywhere in the home unless absolutely silent").
sq225917
Bit of this, bit of that
A linear air bearing arm with a microporous sleeve is an easy way in. You just need air source and a short arm assembly, a la kuzma.
https://www.newwayairbearings.com/catalog/air-bushings-metric/
https://www.newwayairbearings.com/catalog/air-bushings-metric/
I could be wrong, but couldn't you locate a small compressor (aquarium type) in a closet, adjacent room, attic, etc. and run a long tube to where you need the air? It could even have a large reservoir (plastic jug?) along the way to buffer the air and make pressure more constant. It could be pretty silent that way, and you could use a smart plug to control it wirelessly...