interesting phenomena in the cutting room


We've (my friend Bob and myself) been working on an LP cutting lathe for some years. Its been a while refurbishing the lathe itself, finding parts and solving problems/puzzles, rebuilding the electronics, etc.

The lathe itself is a Scully, the cutterhead a Westerex 3D and the electronics the 1700 series built for the cutterhead by Westerex.

About 6 weeks ago we finally hit upon the magic combination of stylus temperature, vacuum, depth of cut, etc. It works beautifully! So we have been playing with parameters, including different amplifiers. The stock amplifiers were built about 1972 and are solid state.

Now those of you that know me know that I am all about tubes. But the stock amps worked quite well! As we gained familiarity with the system, we found out why: the Westerex cutting system is a high efficiency cutterhead- it does not take a lot of power to make the head work. It can easily cut grooves that no cartridge could ever keep up with, and do so without breaking a sweat. So the amps, which can make 125 watts, are loafing through the most difficult passages.

I had a Dyna ST-70 that I had rebuilt so for fun we swapped that amplifier in and it did quite well. Our next step is to use a set of our M-60s, as the cutterhead is an easy load relative to most loudspeakers.

What is interesting about this is that we can make cuts that literally demonstrate the audible differences between amplifiers, something that can be demonstrated on any playback system.

Its also apparent that the cutting process is relatively unlimited as a media compared to any other recording system. The dynamic range is well beyond that of analog tape or any digital system- like I said, it can cut grooves with such range that no cartridge could possibly keep up, yet is dead silent (if the lacquer is OK, that is). The real limitation in LP recording is the playback apparatus, not the cutters.

There is a fun little forum website for more information called 'Secrets of the Lathe Trolls'. Here's a post on that side made by my friend Bob (Bob has run a recording studio for some 20 years and was a roommate of mine in college):

http://lathetrolls.phpbbweb.com/viewtopic.php?p=19435&mforum=lathetrolls#19435
128x128atmasphere
Hello Raul, I didn't know there were new posts to this thread. I'm still trying to sort out this new format Audiogon is using and one of the things that is frustrating is it does not use a good 'new post' system!

Regarding your comments, they were in fact addressed quite well in halcro's response just above. Most of what you commented about is a commonality with all good recordings- you want the recording to be as good as possible regardless of the format.

We've resorted to building our own equipment for the recording process as well. Its not to accommodate anything to do with the LP so much as it is to know that we are giving the signal from the mics the best chance that we can give it!

Overall otherwise I've found the LP format to be pretty accommodating
It has wider dynamic range than tape, and effectively has wider range than CD as well, despite the CD having greater dynamic range on paper. As is often seen in this sport, what is practical and what is on paper are often two very different things!

Y'all have a Happy New Year!
Dear atmasphere: I don't want to disturb you more because you are a busy man especially with the proximity of the CES in January.

I understand what Halcro posted but I'm not talking of the cutting process but the whole recording process, this is what we can read in my first post:


"""  The normal recording process has several characterisitcs that in one way or the other puts its own limitations to the LP playback. """

cutting is only part of the recording process. and what I listed ( one way or the other ) affects the quality level of what we are listening on each LP.

Every recording engineer and LP producer makes things in " similar " way but way different according what each one of them want to " hear " and several times ( the majority times. ) what they " want " is not what we audiophiles want it or like to hear during each one LP listening sessions.

IMHO it's unfortunate that normally the people involved during the recording process been no audiophiles or even music lovers and if they are not audiophiles then unknow  the audiophile community needs.

The Telarc recordings where the producers/engineer were not exactly audiophiles took extremely care in all the recording process and even that are digital recording and vintage ones are ( IMHO ) almost all its recordings really good.
 I posted some examples of very good recordings where its quality is " great " one and there are many other examples of great recordings that even that been not made by audiophiles are very very good. Comes to my mind the Delos label digital recordings that are exemplary, where any one can note the overall care that those people took down there. Wilson recordings or the ones made with K.Alexander involved or the ones by Scottfish label and many many more speaks that the whole recording process can be improved.
     
Now, all of you, imagine what we can listen if all ( or part/some of them . ) the people involved in a specific LP recording process be not only a music lover but an audiophile with the deep knowledge level of what to do to achieve our specific needs. 

I remember the first Stereophile LP recordings where they take care on each link of the recording process even at the pressing process where they decided to press the recording sessions only in one side of each LP.
They made the normal two sides recording and the single side version and I own both and yes the single side has a higher quality level. Stereophile was not the first LP manufacturer that choosed the one side premium LP recording, I have other recordings made it in the same way and explain the why's about.

Certainly I'm not a recording engineer but a plain ignorant in that process but I think I know what to do at each recording process to be nearer to what we listeners want to.

In the otehr side what I would like to see some time in the near future is that some one change/invent a new recording process where all those recording limitations can disappears or at least goes at minimum and I'm not speaking of D2D but D2D could be a very good point to start in that all new recording process.

Who take the challenge? because time goes on and on and the recording technics stay almost the same!!

Till today I never found out a recording engineer/producer that be a TEA not even you.
 You need no presentation, your success as designer/manufacturer speaks for you and you have a very high knowledge technical level that you showed through many posts in this and other forums but ( IMHO and with all respect ) for what ever reasons I can't remember any single post from you where you speak as a TEA.

Anyway, this is what I want share with all of you.

Regards and enjoy the music,
R.





Hello Raul, The acronym 'TEA' returns 67 different hits on Google, none of which make any sense in your post.

But I can say with a great degree of confidence that you are talking about recording challenges and not anything that is specific to the LP.

FWIW we have been experimenting with the direct-to-disc process. We have also been using our OTL amps in the mastering process (still refining that).




Ralph, 
How difficult in terms of budget, contract etc to re-issue let's say Hank Mobley "Soul Station" or Oliver Nelson "Nocturne" from original tapes? Did you try any of a kind?
Dear atmasphere:  """"  I can say with a great degree of confidence that you are talking about recording challenges and not anything that is specific to the LP.  """

I agree that I'm talking of some recordings challenges that ( IMHO ) if we can achieve it can reduce all the recording today limitations that one way or the other has  a direct influence in the quality sound performance in any LP.

What we audiophiles want ( at least me. ) is to improve by wide margin the quality level of what we receive in the LP when the cartridge touchs its grooves. I know ( the samples I posted here and many more tell me that. ) that it can do it using the same recording process and even with out use the D2D technique.

What is out of my mind is why the LP manufacturers did not do it yet. We have ( example ) people as Acoustic Sounds where we pay very high LP price and these gentlemans ( with all respect. ) are so " good-for-nothing " that not even can build and sold dead flat ( at micro and macro levels. ) LP's and dead centered LP's ( with no single eccentricity margin. ). So, what they give us?: more of the same, taking each one " big money " for a product that does not justfy that hig price and all of them take advantage that we have no other choice that following buying those severely " damaged " LP's.

What's all about?, any one of you have the " fix " and useful answer? because if yes then please share with all of us.


Regards and enjoy the music,
R.