Hello!
There's been some interesting information on vinyl records here lately. Was hoping it was possible to get some tips or hints to further reading on the cutting process. Hope this is the right forum, please move if not.
The situation is that the electronic music interest organisation in my little city of Bergen in Norway got hold of a prosumer vinyl cutting machine through government funding. It's a Vestax VRX2000
http://www.vestax.com/products/vrx2000.htm - cutting directly to vinyl from the source. Beautiful little machine! No variable groove distance or other finesses, but it does what it's supposed to do, cutting grooves into vinyl which is much better than regular dub plates. The first totally amateur tries at cutting when it was brand new turned out to be far too noisy. It ended up collecting dust in the office of this organisation after the first dismal results more than two years ago. A shame! So it's been moved to my meager studio. Aiming to improve the results and make a workable routine for the task to hand over to future operators. The machine is wrapped in a dust cover now and will stay there until more or less total confidence in the theories arrives. Got a brand new needle good for 2-300 minutes and 15 blank discs, which is the budget for testing. The machine will be operated entirely on a nonprofit basis and I do this for the love of it.
Some pictures from the first cut:
http://info.bergenteknomafia.com/tech/vrx2000T/Problem is to find information on the subject. Vestax do give some information. Very little actually. They do state that it takes a lot of time and effort to get it right. Doh! This lot of time translates into a lot of money for the blanks and needles. Haven't found much info on the net at all. Haven't heard of anyone else actually owning or operating this machine either. Understood that the AES papers where the bible, am currently waiting for those to arrive in the snail-mail. Also gathered that it needs a microscope fitted, will try to make a contraption to fit one. Only measurements are level VU's and heater current draw, hope it's internally protected against burning the head!
Got some questions I hope some of you experts may answer.
The heater wire action is measured on a VU-style/needle amp meter. The manual states that the proper way to adjust the heater is to look at the vinyl scrap that the needle leaves behind, if they're too thick it's too cold and if they curl up and break it's too warm. This seems too vague to me(like most of the other parts of the manual) so I've been thinking about hooking up a temperature sensor to the heater wire and check the real temperature with the multimeter to find the sweet spot. Will this be a better approach? Microscope? Other method?
The sound level going to the head is also measured on a VU, not peak level. This may overlook some transients the cutter head might not like..? Have no idea what sort of crest ratio a vinyl cutter head likes to get. Should I aim for a high or low crest ratio on the tracks before cutting? Does it matter? The machine will probably spend 99% of the time cutting loud dance floor and scratch-dj tracks.
The machine have a built in RIAA EQ compensation but the curve of the cutter head itself is not compensated in the machine. The manual gives a hopelessly vague chart of it's frequency response which is only a hint to further experimentation. Are most cutting heads almost the same or do they vary wildly between different brands? In other words, can anyone help with the real frequency response of the head? Or any suggestions as to how to compensate for the head?
Locked grooves. It's not made for it. Figure I'll have to stop the cutter head arm motor and lift the needle at precisely 1.8 seconds to make a locked groove. Not likely in reality. It's a much requested feature and if anyone have any suggestions to achieve this it would be plain brilliant!
On the subject of pre-mastering; am looking for spesific time figures for non-skippable sections for playback on a technics S-shaped arm. By looping a sound at 1.8 seconds the needle can skip as much as it wants, it'll always land in identical groove. Almost. Problem is that the spot where needle hits the vinyl on a S-shaped arm, maybe straight arms does this as well, moves away from the tonearm base as the arm travels towards the center of the record. This means that the loop have to be slightly more than 1.8 seconds to a perfect fit. It doesn't matter much for the non-skippable records but if the user wants the attack of the first sound in the loop to appear on the same physical place all over the record it needs more precision. An example is a scratch artist that wants different but similar sounds running along a vertical axis on the record, to be able to drop the needle anywhere on the record to change sounds without cueing to find the attack.
Any help much appreciated!
Cheers,
Andreas Nordenstam (young and learning)
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