Using vacuum tube amplifiers to power the cutting head?

[classicalvacuum]

I've always wanted to reissue classical albums recorded in the 50s through 70s on LP. Electric Recording Co is about the closest I can think of that are doing something like this. Doing some searches I came across this very helpful topic: https://lathetrolls.com/viewtopic.php?t=9769

I do own a few of ERC's reissues and they sound soft/hazy on the top end. Could this be due to them using an under powered vacuum tube amp for the cutting head? I've gone through Electric Mastering's blog and couldn't find details on the types/power amplifiers used. On the other hand I own Blue Note reissues cut in mono on the Classic Records label (Bernie Grundman mastering) that were "tube mastered" that sound like they have sufficient bandwidth. I believe the label claimed that they were using tube amps for the cutting amplifiers.

I would love to hear what more think of this. I would not be taking this on myself, just trying to educate myself in this before seeking out mastering studios in the UK. Thank you.

[classicalvacuum]

To add to this, how much power should I be looking at to supply say a Neumann SX-74 cutting head?

[Dub Studio]

I see no reason why this can't be done, but the problem would be finding someone willing to do it. Folks tend to get used to using a certain finely tuned set up, and might not want to sub out their existing amp.

I seem to remember The Exchange in London had a vintage room with "Scully lathe and Westrex mono 2B/stereo 3D system", maybe they are running a tube amp?

[Discomo]

If you like to replicate the soft tone of music from that era, you should look into preamps which give a lot of color. I can suggest Neve preamps. It doesn’t need to be tube. You have tube preamps which sound ultra clean; used for test equipment. And you have solid state preamps which give a lot of color. I had some great Soviet preamps (tube) which gave a tremendous amount of color. These you can find for a very sympathetic price still. I still have some Neve 1073 and 1084 preamps (solid state). For color and softness of tone, this may all be what you need.

NB: Remember that the entire line, from recording with warm sounding microphones like the famous RCA ribbon microphone in the 40’s and 50’s (they recorded entire orchestras with only one of these in one single take, in the pre multi track or stereo era, positioning the singer close by, strings in the circle around this, woodwinds and drums further away), till 70’s era use of preamps during mixing already gave most of the color. I’m not very familiar with the amplifiers used in the cutting stage, but if I had to guess I’d say they probably used non coloring amps for this, since it was replication they were after.

[buckyhold]

I am currently restoring a presto 28N that was being used with two tube amps. for both lathes separately (obviously...) they are both Altec, one is the 255 and the other is the 256C. i forget what the manual recommends for power ill have to go back to it and if you are interested i could tell you. i know you want to know for the Neumann.

[mich]

Why not?, Neumann vacuum tube amp for cutting had 60watt: