The Secret Society of Lathe Trolls

Hi! No, not from Sweden. A snowy country more in the south... How do you think Ortofon made heads for Lyrec? A couple hours browsing my computer I found that other pic again hehe Guess it is from a museum in Sweden, same custom dial-knob on the right hand side of the machine (pitch adjustement?). Th...

Hi! Great find! That is the very early version - interesting is the turntable with dots instead of line stroboscope, I've seen a similair one on another machine in sweden but couldn't find it on my computer now... Normally the bearings and feedscrew are very good and don't have to be replaced unless...

Some drift BACKWARDS is actually desirable, as the playback turntable is probably using a standard tonearm that pivots, so with a slight backwards drift you actually get a nice curve that lines up to your tone arm's tracking arc.

Ouch, that's something not trivial to predict and compensate for...

As said above I would rather recommend somebody with a good TT - Lyrec will not necesarry keep stable.
Also you can probably judge the quality of the master visually before pressing..

Hey!
Nice project you have there! Good luck with bringing it back to life and hope you find a SP10 in stable good working condition!
Honestly not really interested in the bathtub motor but I'm corious which cutterhead is mounted on there?
Looks like a Grampian or a Cook Mono?

Lukas

What is a proper lathe? I can imagine that this "DJ Tool" is very much used on a "DJ Deck" - probably a 1210. So if it was cut on a well aligned Vinylrecorder with a 1210 it will play back fine on a 1210. If it was cut let's say on a Neumann with Lyrec motor it will probably drift quite a bit... Wit...

New year but to me this already is the best DIY project 2021

Cheers
Lukas

To me there's 2 things: Making a master that is usable for pressing (meeting the technical specs). Making a record that sounds good. The brand/make of equipment is not the reason for it being able to cut a "master" You can also scratch a blank with an exacto knife and send it to the factory if you w...

No, the flip side (the side that is facing to the laser)! The side with printing (brand logo and such) is aluminum coated and printed and NOT really suitable for cutting. I have not tested this with a japanese toy recorder but if you search the forum you'll find a lot of posting cutting and embossin...

Don't know exactly what stuff the original blanks are, but a lot of people here are using CDs (the plastic side not the aluminum coating) for cutting small records.
But you need an adapter to fit the big center hole onto the turntable..

Have fun!

Is the ZA33 the half speed thingy??

I made one with 2 diodes and a transformer....not much rocket science involved

Hmm, from my understanding the 6dB extra gain make sense! A signal that at normal speed is let's say a pure sine with 0dB on the input will be inverse RIAA encoded to about +20dB velocity in the groove (and ends up as an amplitude A in the groove). Cutting at half speed (with doubled time constants)...

Hmm, I made a stereo preamp with the same stuff minus EQ but with feedback control and didn't had big problem with eurocard space...
maybe go for dual mono for that extra mojo

Sounds good - Keep us updated when finished!

Hey! Had a quick look and it seems to do the things you've described. - Input (That) -6dB (but I have not seen a defined input load resistance nor a bias current path!) - 50kHz filter and servo should have unity gain - Low EQ, I don't know because the topology is a little new to me so I cannot give ...

Also on my wishlist since long time - so if anyone has too many...
A photocopy of the one from the NBL would also be highly appreciated

https://www.ebay.de/itm/Original-Neumann-Microscope-Mikroskop-use-with-f-e-SX68-SX74-VMS-SAL/353181147317?hash=item523b3ca0b5:g:qZ8AAOSwoMhfRPL4

...a little pricey for my taste but if you really want an original one...

With the SP10 we have about 0,06-0,08% (measured while cutting) that's way better than with the sl1200 we had before (about 0,18-0,20%).

How do you measure this?

It's doubtful anybody else can do what you're asking.

I guess a lot of engineers can do, the question is if somebody is willing to...
(Ok, nice pitch and good TT help, but not rocket science...)

Hi Lee! Congrats on your new old machine - hope you'll have some good times cutting records with it! I actually saw the auction and was thinking if I should go for it, but probably it would have ended on the long waiting list of things to work on so I didn't bid... Happy you grabbed it and diving st...