The Secret Society of Lathe Trolls

Breaking (off) jaggedly is a common mode of failure after too many hours or (G_d forbid) touching the alu substrate beneath the thin layer of paint on the blank record. I scanned images of broken pickup styli that appear in the AES anthology of Disk Recording (Vol. 1. Groove Geometry and the Recordi...

As you can see, Adamant didn't provide a 'radius of curvature' for the cutting edge, either. It's probably because it's not a curve, innit? It's simply a corner on the mirror that starts the flat, beveled surface which has non-zero length. Ideally, it's a line, this 'corner'. Whereas the tip is deli...

Am using these op amps at unity gain in the test circuit. So the bog-bandwidth used by Max Powers, in this case being 1 MHz, is irrelevant. All the more, this is overkill for audio. Lavry did revise his work-refusal (re: manufacturing 4xFs converters), Please note, however, I'm not talking about the...

Yes, the op amps were stable. There was no clipping - plenty of headroom. At first they, each, sound good, detailed, even exciting. But very close A/B-referencing to the original signal revealed sound-trails being slightly changed - very slightly - meaning, just in the sustain and release modes (re:...

Here's a scan of Adamant's spec sheet for their stereo-cutting (as opposed to CD4) Neumann stylus that Larry included in his compendium.

http://www.discolathe.com/.pdfs/cutting%20styli/Neumann_stereo_Adamant.jpg

The radius of curvature of the new Micropoint stylus tip is 3 - 4 micrometers. http://www.discolathe.com/.pdfs/cutting%20styli/ruby_stylus_B.jpg Whereas, the 'cutting edge' is considered by Micropoint to be 'the intersection of the stylus face (or 'mirror') and the burnishing facet'. http://www.disc...

It's not noise that semiconductors make I don't like, but the enharmonic distortion. I've listened to the same snare drum transient as portrayed by several popular op amps and they all add a certain low level screech to the decay of the snares - making the air-band false. Worse, failing closed is su...

Just because something's new, doesn't mean it's better, so, I'd not 'lose' that (single) Mercury-wetted reed relay (per channel), nor would I add MOSFETS to an existing circuit in order to replace the Merc. (It will have an arrow pointing up, and you'll just have to remember not to turn on the amp u...

-76 user, but thought I'd mention my Nikon transformer psu for the lathe mic is half of what you mention - i.e., 6V / 30 VA. If you're using a bulb that wants to be run at up ro 12V, and if, by chance, your PSU is delivering, at max, only half that, one might expect this dim view... ); Not that you ...

What's not intuitive is that it takes very little power to cut around the primary resonance of the transducer which is usually around 1 - 2 kHz. There's a slight increase in power required for low frequency signals, as one selects a lower and lower test tone, but only up to about 5 Watts - certainly...

Your cutting head needs a lot more power than it can sustain for even one full second in order to make good sound. Al Grundy explained that the average cutting head can dissipate the heat of only 6 Joules (which is 6 Watt-seconds). But it needs amplification of high frequencies for fractions of a se...

The stylus inspection microscope I use is all analog - is a stereo microscope - and the eyepieces show a reticle over the view which allows one to count in tenths of a millimeter. It's useful because it allows the protrusion of the stylus tip to be measured in order to confirm proper seating... The ...

Wonder if Opcode still has some of his clones from 2009. https://deepgroovesmastering.com/.

The RIAA didn't want the pressing center-hole standard to have more than three numbers to the right of the cipher for us to recall. So they forced it to work in fractions of an inch by invoking an unequal tolerance, plus and minus what they state to be the 'center' number. But it's offset, like. Bec...

Thinking of a VR version of how Doug Sax famously 'entrained' the carriages of multiple lathes so that multiple masters or a master with identical refs could be cut simultaneously. Although his lathes were not the 'overhead' / Lyrec type - rather, the Neumann type with leadscrew driving a wheeled ca...

I´m lurking for further technical informations about DMM and how it´s done. Do you know some details about this strange high frequency carrier? Was that used to identify the recording as a DMM or was it of technical importance for the cutting process as such https://www.google.com/url?esrc=s&q=&rct...

Awesome build, ...247. How wide is the groove, across the top, when it looks 'too deep'? (Does it look much wider than most groove-turns on known-playable 'embossed' cuts when viewed on your platter when using the same mic / objective?) Is there any swarf-suction nozzle? (swarf strings visible on wo...

...bidding now over.

Cincinnati, Ohio, USA.