TDS stands for "Dynamic Stereophonic Telephones". "Head Telephone" is same as headphone, just a different term. So it's merely a dynamic stereophonic headphone. Some electret headphones produced in USSR were not named TDS (I'm not sure they were named at all, as it seems that they have not been mass produced).
THANKS! That clears it up a bit more.
If anyone cares:
Went for another Hardware Store visit. Most of this applies to SFI mods, but not all.
A very nice and cheap fiberfill product can be had in those floor vent filters. Basically a more dense version of its big brother/tighter "weave". Also it comes in thin sheets so no tear and end up with wierd shaped blobs. 24 sheets for $4.
As far as
dense felt pads. I have had these for ages I just wish I had remebered before doing all sorts of other stuff instead.
They are buffing wheel/polishing wheel backings. There is a 1/4" thick
ultra dense felt pad with a harder velcro-fuzz disc glued to the back where the sanding pad mounts to. Usually used with some sort of bracket adapter thing on a drill, etc.
the harder disc should be easy enough to strip off, and I can't believe how dense this stuff is. It's
striking actually ( who uses that term anymore, gee willikers )
I found a secret weapon (possibly ) in an old relatively unused halfmask respirator cartridge. I had been thinking of one of these for a while.
I don't recommend cutting these open unless you have a vacuum handy. Loose charcoal.
It gives you a circular baffled filter made from what appears to be soft fuzzy paper filter material. Love the surface area, but it bruises easily, VERY easily. The baffle effect may help diffuse a backwave( that's my theory anyhow ). Ever since getting a hint in the T50 thread about baffling I wanted to find a small usable version. This is it also circular already.
5/8 inches thick ( ~ 1.5 cm )
As well as that there are two fabricy discs that are also potential mods, smoother on one side rougher on the other. These held the charcoal in it's chamber. it reminds me of the dustfilter on the hepa vacuum I have. That sort of fabric where you try to wash it and not much luck with water penetration.
I wouldn't recommend buying these particular respirator filters, too much $, but there may be cheaper alternatives with similar circular baffle filters.
Don't waste your money on forstner bits which I saw were $$$, these Speedbor ones go up to the magic 1 1/2" (
38.1mm ) if you plan on some smeggycups. The 1 1/4" ( 35mm) should give you enough of a decent cavity to sit over.
For adding to the Wikiphonia entries, do I carefully go ahead or should I contact Faust first? Wanted to add those MCS orthos I got, with pics. About time that got done doubtful anyone will run across any more pairs again. Be nice if they did though. Spread the wealth or lack thereof due to here.
That book you linked is interesting stuff thanks for that.