DIY PVC/Acrylic platter + mat

[pradigmshift]

I just finished my DIY PVC/Arcylic platter and mat. It is for a Philips AF-977. I have no experience with tt's but am curious as to what your views are.
Here's what I've done:
- Scrape lables of 5 records (that you don't need!) and put them on top of each other. Check that you will get right VTA.
- Glue the middle 3 records on each other using PVC glue. Before attaching, put some acrylic glue in the lable area to fill the label gap.
- Top record: first apply a layer of PVC glue to flatten out the groove area, then add a thick layer of acrylic glue (elastic kit) using a business card. Keep the lable area free.
- The top record should then be glued with PVC glue to the 3 middle records and the bottom one should be glued with acrylic glue to that. However, since I'm testing I used double-sided adhesive for this.

Usage: the played record will be well supported by the acrylic glue. When the top record is also glued the needle 'feels' five records, not one.
Impressions: I don't have much to compare instead of the orig. alu platter + rubber mat. It does sounds much more natural and more like the same songs on CD. Compared to CD it has a tad stronger mid and a litte less highs/overtones.

Question: Did you try something similar and what were your results?

Credits: http://members.home.nl/fmunniksma/Philips777.htm for ideas

 

[BrocLuno]

:worthless:

 

[Brett a]

Yes, pictures, please!

 

[Arkay]

I've seen mats made from vinyl - just like blank record disks without any grooves or contours pressed into them. The idea, according to the packaging, was that the best material to "drain away" vibrations from vinyl is... vinyl itself. There is some degree of logic to it, perhaps.

Adding layers of a different glue may create a "constrained layer damping" effect, and the irregularities of the grooves would probably break up reflections/refractions (to borrow optical terms) at the interfaces between vinyl and glue. Could/might even enhance performance over that of vinyl along (?).

Another thing that could affect performance is how smooth, flat and even the top surface is, which the record rests on. If you could get the top of your record-stack platter precision-ground to a very smooth, level surface, I think it would improve its sonic characteristics as a platter. You could then add a weight to help "couple" the record to the vinyl below it. You might even go a step further, and line the bottom of the record weight with some vinyl (perhaps even several layers), so vibrations would pass into it in the same manner that they pass into the platter below (ignoring, for this comment, the vibrations coming up from other sources. through the platter).

I'd be inclined to use something that was actually a mild vinyl solvent for the glue medium, to soften the records, and then press them together under some degree of pressure, to ensure they created a fairly solid block with no trapped air bubbles. Then leave them -uh, now fused into an "it"-- long enough for all the volatile solvents to outgas, before playing anything on it. There would be less of the potential CLD effect this way, since there are not two types of glue involved, but vibrations would tend to pass more smoothly away. Not sure if it would be better; probably best to experiment with both approaches.

I've got a Lenco B-52 with a nice idler-wheel drive (same as in the 75), but a lighter-weight platter. I've been toying with what materials to use to "thicken up" and dampen it... maybe I'll get some old, useless records and try this, putting the stack atop the original platter and gluing it down. (Have to keep the original platter for the idler-wheel to drive against; the vinyl would be too soft, I think.)

Your experiment is intriguing; I look forward to further installments! :thmbsp:

 

[pradigmshift]

Pictures at your command
Now, the thing looks a bit boring so I add two more pictures: the external transformer and the bitumen mod (transformer? Who puts these things in record players anyways) and of course, some vinyl in action!

Arkay, very interesting points made, thank you! I might leave my tt like this for a while, sounds really nice with some authentic "wear" effect

 

[pradigmshift]

Update: sounds fabulous! The platter is not 100% flat, but I couldn't hear it affects the sound. For the songs I tried vs CD, I like the same songs more on vinyl now.
Ambience/soundstage/bass definition/detail all is great and when I switch back to my CD player I think it sounds very flat and dull. Just too controlled (IMHO&YMMV apply).
Can recommend this (in combination with the other mods) if you have a tt suitable for this.