Deep Grooves Mastering - Project Bladerunner

[studiorp]

But I am in mistake or here nobody speak about the price ? Thanks.

[dimi751]

Hi stevie


From what I've read in this thread Todd will be selling
Metal or plastic versions of blade runner in dynamic or
Feedback models

Obviously the plastic one is cheaper price but the metal models will be higher price ( correct me if I'm wrong Todd)

There's no where I have seen a exact prices I don't think Todd has posted that yet ?

Anyway I signed up on the waiting list looking forward
To see the final metal version.

Go team mantra woohoo

[studiorp]

We are returned to Cold War, it's a secret state... In each case very good work.

[opcode66]

Possibly 27 but I would request a less compressed song or different musical styles before I committed and then of course there is the cost?

Compressed??? Hmmm. Well, it is Manfred Mann's Earth Band. Rock and Roll from the 80's before over compression was a thing. Here is the volume map of the original wave file used for cutting in this video. As you can clearly see, it is actually a nice production as compared to the truly overcompressed music that is produced these days or that appears in other videos here on the fourm. I choose this track partially for this very reason. It is crisp, clean and un-crompressed. A studio engineer will confirm. I also selected this track because I loved this album when I was about 11 or 12. This and XTC English Settlement. Finally, I did all this work to arrive here. I came for this cutterhead. Therefore, this track. Please feel free to tell me a track or up to 3 tracks that you would like for me to perform test cut with. I will purchase them as I have for every track that I have used for test cut. I will then cut them and post a video just for you. Cool?

For You Original Wave.png

With respect to pricing, I have to start production on metal parts. I am in the process of acquiring metal fabrication equipment now. I just need to start making parts to understand what the costs will be there. Then I can put together finalized pricing. Please be patient.

There are going to be a bewildering number of options. All of which will affect the final price. Dynamic, feedback, hybrid metal/plastic, all metal, color choices, coil DC resistance value 2.7 or 4.7 or 9.4 or custom value. If feedback, then many options for the rack unit: VU meters, monitor switch (input, feedback, phono), electronic heat coil heat detection and breaking instead of fuses, phono preamp with RIAA that can be disabled. If no feedback, then a basic rack with IRIAA, heating supply, fuses and ammeters. Or no rack whatsoever. Therefore, there will be a quote generator on my web site much like the one there now for pressings. So, please be patient. I will say that I am going to try my best to keep pricing consistent with Caruso if that gives you a ballpark.

One further question what is the dreadful grating noise?

Of course. I am not wasting new needles to perform test cut using experimental prototypes. That simply makes no sense. I am using styli that are worn or even slightly damaged that I have collected over the years as a consequence of doing vinyl mastering and cutting dubs. These are all 320 Sapphire styli from Appollo. 4 micron tip radius. I don't waste new ones because there are many reasons why styli can get damaged as one experiments with prototypes. For instance, changing out cutterheads going from my Neumann to my Bladerunner proto takes some adjustment of my suspension. Occasionally, i've neglected to adjust the height of the suspension and sheared the tip of a stylus. Or, I've made an experimental torque tube and it was holding the stylus correctly and it gets damaged. Why use a new one, right? Therefore, background noise in the cuts. Additionally, in the video itself, you can see I put text on screen saying that the disc is warped. It was a test disc from Chicago. It still had some space on it so I used it. Again, being frugal with the testing supplies up to now. That disc took a bit of a hit int he move. Therefore, has a bump on it. It can be heard as noise in playback. This is identified in the video.

The other thing to consider is that you are making judgements based on plastic parts. A metal torque tube will produce a much finer groove with less noise. What you should really be saying is "Wow, I can't believe you are getting such fantastic sound with a fucking all plastic cutterhead. That's amazing. Yes, a little noisy, but it is all fucking plastic man. Good work Todd".

Aside from that excellent work and of course if I should commit I assume we would get a choice in colour/finish rather than that dreadful pink. Or did I miss read and the potential orders you are taking are for metal stereo cutter heads, such a long thread it's easy to loose track.

Yes color choices in plastic. No color choices in metal. The color of the cutterehead body is purple not pink. Maybe check the tint settings on your monitor??? It is True Purple filament from Makerbot. If you hadn't noticed, I've been using all sorts of colors over time. Each of the colors prints a little differently. So, I've wanted to try the whole range of colors. Therefore, I've been using each over time. I like a black body personally, but someone here suggested printing the body in colored plastic because a black body hovering over a black disc is hard to see. Therefore the colored bodies. The next is going to be True white body with purple highlights.

I would have thought everyone would be thankful for all the content and transparency of my documentation instead of discouraged by its volume. If I didn't do as much documentation as I have, then someone would complain about the lack thereof. So, damned if you do, damned if you don't sort of arrangement here.

The only other issue for me is one of mounting, as it would go on my second Sugden lathe, it just needs to bolt to the bracket (carriage) centre screw mount ((it will be Imperial not metric)note to self get a screw thread gauge). I assume depth from front to back is about 50mm (just to mix it up a bit), sorry 40ish mm, just measured roughly.

I do not know how a Neumann mount works never seen one, but the back plate on the Sugden is threaded and I can swing the bracket up so it would need to be fixed from the back. The big screw in the sugden pictures is that very mounting screw.

The back of the cutterhead is flat mate. I can sink tapped holes to suit. And, I will be making customized mounts and brackets for a number of different overhead mechanisms inlcuding Presto, Fairchild, Neumann, Scully and Vinyl Recorder to name a few. I will also make custom solutions for a reasonable price. Does this work for you?

FYI, since the Mantra cutterhead fits the same footprint as the SX cutterhead with respect to the critical dimensions for cutting, it can even fit like this SX on a 6n

SX68 on the Presto lathe.JPG

No offence meant but as I am across the pond economically it might be better for me to opt for the metal European option, with import duties etc, it may be easier, my mind is not made up one way or the other but I would like a stereo cutter head based on a Neumann.

None taken. I'm so chill these days. Plus, all men and women should be free to make their own choices, of course. It is only natural. I obviously have no way to circumvent customs. Sorry. Not into the black market trade. I would, naturally appreciate your patronage and do hope that I can supply you with a quality cutterhead that you will enjoy for many years. The other thing to note that is unique to my work is the modular design. That fact that with replacement parts, anyone with a screwdriver set can perform a self repair to any part of the system. Name one of cutterhead that has that feature.

The only other issue I can see is that the Sugden is a fixed head system, the head is mounted rigidly and there is no system to control vertical movement other than cutting angle. Is this an issue with a stereo cutter head. Depth of cut is controlled by a second stylus (rounded) behind the cutter head, it's fixed, you can move it around one way or the other, to increase or decrease depth of cut.

Let's solve that issue once we get there, shall we? A mount could be made that incorporates depth control. Fuck, I could build it into the back of the cutterhead. All problems have ellegantly simple solutions if you have the time and desire to arrive at them. Coolio? Don't worry about it.

[opcode66]

We are returned to Cold War, it's a secret state... In each case very good work.

LOL Not hardly. If you are referring to the fact that I am keeping some of my discoveries to myself as they pertain to the proprietary aspects of my cutterhead system, then natrually it isn't within my best interests as the potential marketer and supplier of these devices to detail every aspect of their functioning to you or any potential customer.

Let me pose a query. Did Neumann tell everyone all of the exactitudes of the mechanics of their cutterhead system? Did Westrex? Does Flo? I mean, if you want to talk about a lack of public documentation (i.e. a secrets vortex) have a look at his explanations of the inner workings of Caruso (or complete lack thereof).

I will submit sir, that you're getting a little carried away with the metaphor. Not doing anything that any other company does when they develop, market and produce a product for consumption.

In reality, I've documented my work more than any maker of cutterheads to date. I suppose that is my opinion. But, just look at the length of this thread. And the fact that this all actually started with these additional threads (additional documentation) below which would represent even more transparency on my part. Just because I am keep one or two things to myself and exposing everything else, I am the Kremlin or the CIA? Please be fair. I know it is a joke. I'm not offended or anything. It is just that I am actually being so transparent. Direct that at someone who is being less than forthcoming. I can think of a few folks who would fit the bill there.

Deep Grooves Mastering - Opcode66 Transducer Project - Mon Sep 08, 2014 1:22 am
http://lathetrolls.com/viewtopic.php?f=15&t=5206&hilit=coil+transducer+deep

Deep Grooves Mastering - Feedback Transducer - Wed Apr 08, 2015 12:22 am
http://lathetrolls.com/viewtopic.php?f=15&t=5610&hilit=coil+deep

Deep Grooves Mastering - Now Offering Mono Coil Repair! - Mon Sep 08, 2014 1:09 am
http://lathetrolls.com/viewtopic.php?f=15&t=5205&p=31290&hilit=rca+coil+deep#p31290

[opcode66]

So you guys understand, up until now, this has been the extent of my metal machining capabilities. A dremel, a drill press and a shop vac. Not much. Very limited what I can do. Certainly, I'm unable to make anything useful in metal for the cutterhead.

IMG_8331.JPG

This is the best I can do for square cuts in metal.

IMG_7932.JPG

IMG_8009.JPG

With the desktop CNC and Lathe and a laser engraver I will be able to produce parts for the cutterhead and very nice interface panels for the rack gear. I will also send panels out for silk screening. Finally, I'll be able to use the CNC to make circuit boards as well as use the it to make blanks from squares of plastic. Should all be setup by January or February.

[opcode66]

Another consequence of the work I've been doing which hasn't really been stated yet is that I'll be able to make DMM cutterheads eventually as well. So, think about that for a minute fellow Trollsmen. Just need to learn to be a machinist in the coming months. But, this too is possible.

[studiorp]

It's Italian humorism, if you understand good, otherwise patience... Here nobody judge your work, remember.

[Stevie342000]

Possibly 27 but I would request a less compressed song or different musical styles before I committed and then of course there is the cost?

Compressed??? Hmmm. Well, it is Manfred Mann's Earth Band. I also selected this track because I loved this album when I was about 11 or 12. This and XTC English Settlement. Finally, I did all this work to arrive here. I came for this cutterhead. Therefore, this track. Please feel free to tell me a track or up to 3 tracks that you would like for me to perform test cut with. I will purchase them as I have for every track that I have used for test cut. I will then cut them and post a video just for you. Cool?

For You Original Wave.png

With respect to pricing, I have to start production on metal parts. I am in the process of acquiring metal fabrication equipment now. I just need to start making parts to understand what the costs will be there. Then I can put together finalized pricing. Please be patient.

Therefore, there will be a quote generator on my web site much like the one there now for pressings. So, please be patient. I will say that I am going to try my best to keep pricing consistent with Caruso if that gives you a ballpark.

One further question what is the dreadful grating noise?

Of course. I am not wasting new needles to perform test cut using experimental prototypes.

Aside from that excellent work and of course if I should commit I assume we would get a choice in colour/finish rather than that dreadful pink. Or did I miss read and the potential orders you are taking are for metal stereo cutter heads, such a long thread it's easy to loose track.

Yes color choices in plastic. No color choices in metal. I like a black body personally, but someone here suggested printing the body in colored plastic because a black body hovering over a black disc is hard to see. Therefore the colored bodies. The next is going to be True white body with purple highlights.

The only other issue for me is one of mounting, as it would go on my second Sugden lathe, it just needs to bolt to the bracket (carriage) centre screw mount ((it will be Imperial not metric)note to self get a screw thread gauge). I assume depth from front to back is about 50mm (just to mix it up a bit), sorry 40ish mm, just measured roughly.

The back of the cutterhead is flat mate. I can sink tapped holes to suit. And, I will be making customized mounts and brackets for a number of different overhead mechanisms inlcuding Presto, Fairchild, Neumann, Scully and Vinyl Recorder to name a few. I will also make custom solutions for a reasonable price. Does this work for you?

FYI, since the Mantra cutterhead fits the same footprint as the SX cutterhead with respect to the critical dimensions for cutting, it can even fit like this SX on a 6n

SX68 on the Presto lathe.JPG

No offence meant but as I am across the pond economically it might be better for me to opt for the metal European option, with import duties etc, it may be easier, my mind is not made up one way or the other but I would like a stereo cutter head based on a Neumann.

Not into the black market trade. I would, naturally appreciate your patronage and do hope that I can supply you with a quality cutterhead that you will enjoy for many years. The other thing to note that is unique to my work is the modular design. That fact that with replacement parts, anyone with a screwdriver set can perform a self repair to any part of the system. Name one of cutterhead that has that feature.

The only other issue I can see is that the Sugden is a fixed head system, the head is mounted rigidly and there is no system to control vertical movement other than cutting angle. Is this an issue with a stereo cutter head. Depth of cut is controlled by a second stylus (rounded) behind the cutter head, it's fixed, you can move it around one way or the other, to increase or decrease depth of cut.

Let's solve that issue once we get there, shall we? A mount could be made that incorporates depth control. Fuck, I could build it into the back of the cutterhead. All problems have ellegantly simple solutions if you have the time and desire to arrive at them. Coolio? Don't worry about it.

That all sounds good to me, just wanted to pull some of the information together, as this is a really long thread, with a lot of information that is relevant to me. You could not say you have not shared. The colour you used is very close to our corporate city colour, oh yes some marketing guys idea as it is so opposite to what the city is like.

Yes agreed, my stupids I had forgotten you had said you were using a chipped old stylus, I would not wish to use a new one but you could try a cut with the same track with a new stylus for comparison?

I am no more into black market deals that you are, what I am talking about is the cost, you have to weigh up the benefits and on the basis that yours is modular, in the longer term it might be cheaper.

Can not wait for the metal version and to see that there are options to suit all, as well as a calculator for quotes. If I remember rightly as it is modular you could start off with a non-feedback head and switch the coils at a later date?

As for tracks for me some jazz would be good, how about something from the Cole Porter songbook -Ella Fitzgerald or Quincy Jones Soul Bossa Nova USA which is a bit more dynamic. You do not have to buy them you could rip a copy from YouTube (they are of course not the best quality but there are some good rips), I listen on one of those DAC boxes 24bit/192kHz. The track you used I am not familiar with, although I know the band, not into 80s rock, was more in to dance music in that era.

Very interesting that we could factor in some kind of depth control for my lathe. I may be some way off making a final decision but I will have to get saving for a start.

The Keep It Simple Stupid approach ah yes, my favourite, just like the Sugden lathe it is really simple and well engineered.

[opcode66]

I appreciate you helping to do some crib notes here at the tail end of a mighty mountain of a thread. Thanks man. Cheers!

Now that I trust the configuration much more than in the past. The lines are all correct. I'm able to repetitively achieve the same cutting angle after head swap outs, etc. I am much more willing to put a fresh stylus in the current prototype. That is the plan. Also going to pull a fresh, brand new lacquer for the next test cut. Something else I didn't mention is that the plastic torque tube will not allow me to apply as much heat as one would normally for cutting silent grooves. If I apply 0.4 to 0.5 amps, the plastic in the torque tube becomes malleable and will deform and the stylus will no longer be held correctly. Once I have a metal torque tube, I will be able to apply full heat and more background noise will disappear.

I fully agree, jazz would be some perfect program material. I will grab some of the music you suggested. I always purchase it for legal reasons. I post videos with the music. To be a part of the fair use principal, I have to purchase it. Also, cutting the music in my videos represents me making a backup copy of the music I purchased. So, no laws are violated. That is why. If you can't tell, I'm into doing things "on the level". Fair and equal.

The modular design could be cheaper from the standpoint of if, and let's hope this never happens, if you blow a coil.... You can repair your cutterhead yourself very quickly. The alternative is shipping your cutterhead to someone for repair. That takes months. Sometimes cutterheads are lost in the mail. Other times people walk off with them ala PrestRepairs in Australia and are never heard from again. That would be a huge loss. So, the ability to keep your cutterhead in your possession and perform critical repairs yourself is extremely economical and is much safer proposition in the long run. Even the torque tube assembly is modular... Not just the transducers. All critical parts are self repair. If you ship your cutterhead out for repair and you cut records for a living, think of what 2 to 3 months without your cutterhead would do to your budget. That is also something to consider when looking at this economically. Also, you may loose customers in that time period. Something else to consider.

I can't wait for metal either my friend. I can't wait to incorporate metal fabrication into nearly every project I work on. It will be fun to learn to be a machinist like my Grandfather was on my mom's side. Yes, dynamic heads will come wired for feedback. You'll be able to upgrade transducers and make a dynamic head a feedback head.

Keep your questions and comments coming please. It helps.

[markrob]

Hi,


Looks like you are moving along nicely.

If you post any more test cut rips, can you also post the same section of music of the original source material. That would make it easy to compare. It would also be good to let us know the conditions under which the cut was made. For example, RIAA applied, any corrective EQ applied to the source material, amount of feedback applied, average power to produce the cut etc. It would also be great if there was some way to determine the level of the cut vs. some standard (1 Khz 5 cm/sec).

Have you determined a power rating for the head in its present, all plastic, form? How much power must be applied to the head to achieve 5 cm/sec at 1Khz?

Mark

[Stevie342000]

I appreciate you helping to do some crib notes here at the tail end of a mighty mountain of a thread. Thanks man. Cheers!

Now that I trust the configuration much more than in the past. The lines are all correct. I'm able to repetitively achieve the same cutting angle after head swap outs, etc. I am much more willing to put a fresh stylus in the current prototype. That is the plan. Also going to pull a fresh, brand new lacquer for the next test cut. Something else I didn't mention is that the plastic torque tube will not allow me to apply as much heat as one would normally for cutting silent grooves. If I apply 0.4 to 0.5 amps, the plastic in the torque tube becomes malleable and will deform and the stylus will no longer be held correctly. Once I have a metal torque tube, I will be able to apply full heat and more background noise will disappear.

I fully agree, jazz would be some perfect program material. I will grab some of the music you suggested. I always purchase it for legal reasons. I post videos with the music. To be a part of the fair use principal, I have to purchase it. Also, cutting the music in my videos represents me making a backup copy of the music I purchased. So, no laws are violated. That is why. If you can't tell, I'm into doing things "on the level". Fair and equal.

The modular design could be cheaper from the standpoint of if, and let's hope this never happens, if you blow a coil.... You can repair your cutterhead yourself very quickly. The alternative is shipping your cutterhead to someone for repair. That takes months. Sometimes cutterheads are lost in the mail. Other times people walk off with them ala PrestRepairs in Australia and are never heard from again. That would be a huge loss. So, the ability to keep your cutterhead in your possession and perform critical repairs yourself is extremely economical and is much safer proposition in the long run. Even the torque tube assembly is modular... Not just the transducers. All critical parts are self repair. If you ship your cutterhead out for repair and you cut records for a living, think of what 2 to 3 months without your cutterhead would do to your budget. That is also something to consider when looking at this economically. Also, you may loose customers in that time period. Something else to consider.

I can't wait for metal either my friend. I can't wait to incorporate metal fabrication into nearly every project I work on. It will be fun to learn to be a machinist like my Grandfather was on my mom's side. Yes, dynamic heads will come wired for feedback. You'll be able to upgrade transducers and make a dynamic head a feedback head.

Keep your questions and comments coming please. It helps.

Absolutely agree about applying heat to the plastic torque tube, your stylus would probably end up mis-aligned as well, it is definitely the weak link in the chain.

All good so far, those who have got the budget could purchase two bodies or more coils feedback, non-feedback, spare torque tubes and so on. Yes very well thought out and if the parts are metal then they should last a good while, probably just as well to stock up spares (as a purchaser) just in case anything should something happen to the supplier or the supply chain.

But not too many as I would suspect you will continue to tweak the design or replace it with another, thus some parts may not fit a newer design, should that come along at a later date.

Yes I have just been sat here lurking in the background watching and reading, I thought it was time to speak up and clear up any issues I had, others may like to chip in with anything I have missed.

Oh yes black metal would be good, if you got good light you get a reflection, I don't see the issue, unless people are going to sitting there stroking it going precious (lord of the rings), shiny....

One other thing, I see in one of the classifieds threads some is looking for the scale for the Neumann microscope, hmmm you know what I am think, how many could you fit on a printed laminate sheet? I have a microscope which I have got to modify to fit to one of my lathes, once I have figured it out, I will get another. It's 70X magnification, not sure if that is enough but its a well made small hobby scope.

I am looking at a scale so I can gauge groove width, any ideas? I know that is off the scope of the project here but just an idea.

Well at least we all know what a groove cut with a chipped stylus sounds like now. Yes agreed on the purchase of original material, I think you will find the Quincy Jones on the Best of and the Cole Porter Song book was available on CD, I have the latter on original US vinyl (Verve) recorded in Capitol Tower not long after it opened. For those that do not know Soul Bossa Nova get away with you, its the theme tune to Austin Powers. It will test your high end, try to get the original version, yes I have the vinyl album as well.

Downtime could be costly to all, I am more of a hobbyist, yes on the case with machining myself, I am due to move south to my parents home for part of the week and the rest of the week back in Manchester (England). My father has toys he has a full workshop and I asked him to show me how to do some machining.

Go for the Gingery books on machining, they show you how to make your own lathe, castings, milling machine, machine press, drill press and its a good way of recycling aluminium cans. The metal option may take longer than you think? You have to learn how to machine first, you have lots of castings either to get made or to make, they take time, making them yourself will lower your costs.

Aluminium will lower your overall weight and it is a good thermal conductor, non magnetic and easy to machine. Any drilling is going to be critical, especially the hole in the torque tube, may I suggest brass? Dremel will come in useful for that I would think.

Oh my head hurts now and soon I will bump up against the word limit on this post. I have briefly glimpsed the next post. I would figure about 2 volts rms should be a ball park guestimate figure to do a cut at 5 cm/sec at 1kHz.

[Stevie342000]

Hi,


Looks like you are moving along nicely.

If you post any more test cut rips, can you also post the same section of music of the original source material. That would make it easy to compare. It would also be good to let us know the conditions under which the cut was made. For example, RIAA applied, any corrective EQ applied to the source material, amount of feedback applied, average power to produce the cut etc. It would also be great if there was some way to determine the level of the cut vs. some standard (1 Khz 5 cm/sec).

Have you determined a power rating for the head in its present, all plastic, form? How much power must be applied to the head to achieve 5 cm/sec at 1Khz?

Mark

All of the above would be useful for the plastic version right now but all would change when you use a metal torque tube or move over to a full metal jacket.

[ilovethelawrencearms]

haha yea that is definitely not over compressed. Do you have the original audio? Would love to hear the difference.

[opcode66]

Hi,


Looks like you are moving along nicely.

If you post any more test cut rips, can you also post the same section of music of the original source material. That would make it easy to compare. It would also be good to let us know the conditions under which the cut was made. For example, RIAA applied, any corrective EQ applied to the source material, amount of feedback applied, average power to produce the cut etc. It would also be great if there was some way to determine the level of the cut vs. some standard (1 Khz 5 cm/sec).

Have you determined a power rating for the head in its present, all plastic, form? How much power must be applied to the head to achieve 5 cm/sec at 1Khz?

Mark

Nice of you to drop by.

Sure. No Problem. Here is the section of the original WAVE. I purchased the full album on iTunes. I used iTunes to Convert to Wave from m4a. I cut the first 2 minutes of the track. So, here are the first 2 minutes of the original file. I'm not posting the full file for copyright reasons.

03 For You - Clip.zip

There are obvious differences. I don't have perfect representation yet. But, I can't stress this enough, I have zero critical metal parts. Compounded with shitty stylus and shitty media. And, I'm still working out a mount that will achieve a proper cutting angle now that my stylus is reliably and repeatedly 90/90 when seated (even if I make new parts all goes together flush and straight now). So, audio quality will naturally and dramatically improve from here. The various systems are working though and this recording is evidence of that. Please keep this in mind and be fair. Metal will make the cutterhead sing in ways that plastic simply can't implement. The design is sound. The parts suck. Sounds like some cars I can think of. LOL

As has been stated repeatedly in this thread, all cuts are made with iRIAA processing only. Previously implemented via your VST. Now implemented via my Caruso pre-amp build. All cuts are made with feedback since two videos ago. Moving forward I will tell you if I'm cutting dynamically. In fact, I plan to make some comparison cuts that way. But, I will point that out in the videos. All cuts are made at 45 rpm and about 250 lpi. Volume level varies a bit by track. I don't apply eq curves because up till now I've been trying to refine the natural response of my transducers which are beginning to get fairly flat. If I ever deviate from this standard I will tell you all in the video.

When you say amount of feedback applied, exactly how do you want me to measure that my friend? Do you want me to tap into the feedback after preamplification and before negative summing? Before preamplification? Do you want me to measure the feedback monitoring? What audio should I be running while measuring? Do you want some subject estimated percentage based on how many turns of the trimmer? I mean, so many ways to answer that. You are normally so discrete when quoting from books. Please be specific. I can say if I dial in about 7 to 8 turns on the trimmer then I am sitting pretty with respect to response. If you watch my Osc Scope Feedback Video you'll see that.

Power... I am waiting for metal parts to set the specs as they will certainly change. I see no point measuring that at this time. You'll have to wait on the wattage. However, if you had any experience at all cutting practically on a Nuemann, you would be able to see that the excursion in my grooves as seen on disc in the videos via my scope matches that of the SX. I have my gain knobs on my QSC GX3 at 1/4 power or less (3 ticks up from infinity is good). So, not a lot of power for the same excursion in similar frequencies ranges. All told, that means this is an extremely efficient system. On par with my SX. But, I will give you the numbers when I am ready for sales in the literature with everyone else. Also, I won't measure until I have metal.

I feel like writing a song at this point. I got The No Metal Blues.

[opcode66]

But not too many as I would suspect you will continue to tweak the design or replace it with another, thus some parts may not fit a newer design, should that come along at a later date.

I will always support any previous model. Though I don't see a need that would arrise that will require me to make major dimensional changes to the body or transducers at this point. I think the parts may get refined, yes, but maintaining backward compatibility won't be hard. And, I'll always know what parts went with what serial number. I will have a very detailed database, so I'll know exactly the configuration of every head sold or upgraded. You worry way too much my friend.

Oh yes black metal would be good, if you got good light you get a reflection, I don't see the issue, unless people are going to sitting there stroking it going precious (lord of the rings), shiny....

I was saying that I like the black plastic bodies. Black metal would be very costly. Not sure anyone would want that....

One other thing, I see in one of the classifieds threads some is looking for the scale for the Neumann microscope, hmmm you know what I am think, how many could you fit on a printed laminate sheet? I have a microscope which I have got to modify to fit to one of my lathes, once I have figured it out, I will get another. It's 70X magnification, not sure if that is enough but its a well made small hobby scope.

Neumann scope is 208x magnification and illuminated. It is graduated in Mils or Micrometers. There really aren't great substitutes available cheap. They are all very costly if you want something close to the original. Digital scopes have crappy resolution usually (2 Megapixels or maybe 4). My phone has a better camera. Trying to see definition in the groove walls with a cheap USB camera is nearly impossible. You won't be able to really see streaking or if the groove walls are mirrored or not. Etc.

I am looking at a scale so I can gauge groove width, any ideas? I know that is off the scope of the project here but just an idea.

I cut a minimum of a 3 Mil groove width (1.5 Mil depth). A Mil is 1/1000 Inch. Sometimes a little deeper.

Well at least we all know what a groove cut with a chipped stylus sounds like now.

It is actually mostly the severely warped disc that you are hearing, fyi.

Go for the Gingery books on machining, they show you how to make your own lathe, castings, milling machine, machine press, drill press and its a good way of recycling aluminium cans. The metal option may take longer than you think? You have to learn how to machine first, you have lots of castings either to get made or to make, they take time, making them yourself will lower your costs.

Aluminium will lower your overall weight and it is a good thermal conductor, non magnetic and easy to machine. Any drilling is going to be critical, especially the hole in the torque tube, may I suggest brass? Dremel will come in useful for that I would think.

Thanks. Obviously, I've been doing preliminary study that I simply haven't mentioned. I appreciate your input, but, I got this. If you hadn't noticed by now, once I desire something, I achieve it. No level of complexity is unapproachable to me. And, I learn and adapt very quickly. So, don't worry, I will have parts quickly enough. And, I see the hurdles to surmount.

[markrob]

Hi,

I wasn't specific since I thought you knew the correct procedure. No need to be snippy.

To measure the amount of feedback, you start with zero (open loop) and apply a sine wave at or near your system resonance. Adjust the drive to a reasonable level that will not cause any damage. Measure the signal at the head and set this as your 0 dB reference point. Now start to add feedback. As you increase the feedback level, the drive level to the head will drop. When you reach the limit of how much you can apply without seeing any instability, make a note of the total drop in level from the 0 reference.

Mark

[opcode66]

I'm not being snippy Mark. I'm asking you to be specific. Holding you to the same standards I am. Maybe everyone out there doesn't know the procedure. Now they do, sort of (see corrections below). Also, there are many ways to "measure" this as I pointed out. Some of them would be inaccurate or incorrect. Good for the readers to know the difference. Sometimes I pose questions to elicit the answer for our viewers. Other times, I just want to know if you know.

Actually, the best way to measure this is not by measuring drive level. The best way to measure this is to measure the actual true response on disc. I would need to have the phono pre section of my Caruso build finished and installed. I would then need to calibrate it via the NAB disc. Then, I would use the Phono monitor setting on the Caruso. I would cut 1K tone and I would be monitoring Phono Level on VU meteres. I would set the drive level so I am reading 0 VU with zero feedback being applied. I would then dial in feedback gradually and I would watch the latent reaction on the VU meters. As stated by Flo and Neumann if you can get a 9db drop (i.e. dial in feedback until the meter reads -9 VU from 0). then you are golden. If less than 9db then you may want to review the design.

Measuring electrical drive to the head is not a true measurement. Measuring the actual response on disc is. But, I have no idea what your actual calibration procedure is. Or what you gear you have for that matter. Or, how it is all hooked up. Or if you even have a lathe at all anymore. So, therefore the question I posed to you. I can ask you stuff, yes?

[Ciuens]

The procedure that Mark suggested is exactly what Flo demonstrates this video

http://www.floka.com/caruso/caruso_feedback_setup1k_s2.mov


In my cutter head i'm getting 31db of negative feedback in the first resonant frequency (1.35khz)


Ciuens

[opcode66]

I can post the Neumann calibration procedure. Drive is never monitored or measured directly. I am basing my system on Neumann. Which is why I have a monitor selector that matches the monitor section on the SAL rack. I'm going with the professional standard. If your system doesn't perform to professional standards, then getting demonstratable results my way is a lot more difficult to achieve than what you all are describing. You dig? That is likely why others may do it that way... becaus they wouldnt have the same drop after mechanical translation... And the results wouldn't look as impressive overall.

If you Are ok with slightly skewed results and want to demonstrate for folks to perform a calibraion on a system that doesn't include a phono pre-amp, then yes, you have to measure drive. Caruso comes with no phono pre so a true calibration procedure is not demonstratable by Flo on his stock gear. Ask him.

However, if you want to demonatrate true response, and you have an integrated and calibrated phono pre, the way I've described is the only way. And true response on disc is what I am going for of course.

The calibration procedure was posted as a pdf in another thread here on the Trolls for Neumann. Please read it. It will confirm: 9db drop via the method I described and you never monitor drive direclty. There is no drive setting on the monitor selector in a SAL or VG rack from Neumann. So, I am correct for the specification that I am looking to emulate and surpass.

Great discussion today by the way gents. I think everyone has learned a little something.