The farmer and his plow - When I set out to build a record cutter

[farmersplow]

Hello, Do you have a test vinyl record? I have such a vinyl record, the left channel and the right channel are recorded separately, then two channels are simultaneously in phase and anti-phase, and you can hear the difference between the left and right channels precisely, and, for example, the signal from the right channel slightly penetrates the left channel and vice versa. Recording a stereo signal in one groove is not a simple process, more is needed than the appropriate polarization of the drive coils. If anyone knows this topic, please speak up on this matter, I will be happy to learn more, best regards

Hello zdenek, yes I have a test vinyl record. And it is clear that you can hear a stereo signal on both phase and anti-phase, and you can also hear the left and right channels. That's because you have a stereo cartridge mounted on your record player. Mount a mono cartridge once and you will immediately notice the difference.
Cutting a stereo signal into a groove is of course not an easy thing to do. But it has basically nothing to do with the polarization of the driver coils. The polarization is only a subsequent step to facilitate the cutting into the blank for the cutting stylus and thus to get a better signal (and to make it audible for mono pickups as well).

[zdenek]

Hello, I don't know if you understood me, but I will try to explain to you how I understand it.
If you connect the transducer coils of the left and right channels in such a way that one transducer pushes the tube with the cutter and the trugi pulls the tube with the cutter, this will be the sum of the left and right signals in a monophonic configuration, the recording will be exclusively mono in the full band that can be reached by the sum of your magnetic transducers, and now be careful that in order to record the stereo signal in one groove there must also be vertical modulation of the left and right channels, i.e. their time difference, i.e. the stereo signal is the time difference and the stereo difference of the recording in vertical modulation, limited by various types of limiters for vertical modulation i.e. the recording depth, there is no problem with horizontal modulation, there are only physical and mechanical limitations of the transducers. To obtain a stereo recording in one groove and a mono recording in the same groove, the signal must be encoded in some way. The knife in stereo recording cuts a groove that is not flat or almost flat, but in stereo it is almost three-dimensional, the stereo signal is encoded only in vertical modulation and is the difference of the left and right channel signals, as I understand it. Reading with a stereo or mono cartridge is much simpler than writing on a lacquered disc, the case is in this case is obvious.Therefore, we need some device that encodes the analog signal to make stereophonic recording possible in one groove, but what kind of device and what is its name?

[farmersplow]

...If you connect the transducer coils of the left and right channels in such a way that one transducer pushes the tube with the cutter and the trugi pulls the tube with the cutter, this will be the sum of the left and right signals in a monophonic configuration, the recording will be exclusively mono in the full band that can be reached by the sum of your magnetic transducers,

... we need some device that encodes the analog signal to make stereophonic recording possible in one groove, but what kind of device and what is its name?

Hello, I think I understand what you mean. If I would connect the left and right channel converters, then I would have only mono. But I don't! I'm just changing (like any stereo cutterhead) the polarity of one of the two drivers.
"Stereo is nothing more than two times mono".
First you cut mono only by having one driver move the stylus from top to bottom.
Then they cut mono by one driver moving the stylus from left to right (better quality and easier to press).
Then came stereo: one driver moved the stylus at a 45° angle from top left to bottom right and the second driver moved it from top right to bottom left (three-dimensional).

Example: There is a 1000Hz sound on the left channel and 3000Hz on the right channel. Then the stylus moves 1000 times per second from top left to bottom right and 3000 times per second from top right to bottom left. No matter how the two drivers are polarized.

But if there are 1000Hz on both channels, what happens?
Then I have in effect = mono (and only if the same frequency is applied to both channels). Then the stylus moves 1000 times per second from top left to bottom right and 1000 times per second from top right to bottom left.
In this case the polarity shows its effect. Because if both driver coils had the same phase, they would go down and up at the same time. The result would be the worse vertical cut method. But if one of the two drivers is reversed in polarity, then one would push the tube and the other would pull. The result would be the better horizontal motion. And only if both frequencies are the same! (Which "unfortunately" happens very often. No device is needed to encode the analog signal. That's why stereo cutting heads have the two driver coils arranged at 90° to each other (45° + 45°).

I hope I could explain it.

[farmersplow]

Breadboard – Electronics
(04 2023)

So that finally everything runs, I still need a controller! Since this part of the project is also quite complex and consumes a lot of time in detail, I would like to deal in this treat only with the most essential areas.

First of all there is a breadboard:
A way to build all the necessary components provisionally first. Then you can experiment with the parts, components and wires to create a working controller.

Apart from the components that are already mounted on the lathe (platter drive, stepper motor, cutting head suspension and cutting head), there are still numerous components that will only be mounted later on the finished overall device.

First of all, there is a connection panel on which the audio signal inputs and outputs are located. Also the connections for the power amplifier.
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Next are the controls to tell the lathe what you want to do. This includes a few buttons (start the cutting operation, perform a “track marker” between the songs, create the final run-out groove up to the final line).
Also a key for “ABORT" belongs to it, as well as a few knobs and so on. Also a slider for fine adjusting the turntable speed by up to +/-50% (Half Speed Mastering).
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The "module" for the stylus heater with mA meter, fuse and (reserve) ON-OFF switch.
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Very important is a large dB display that shows the signal that is present at the cutterhead.
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In addition, a few displays that regulate my beloved automatic heating control (IR temperature sensor, OLED display and three LED's red, green, blue for too hot, OK and too cold). Of course, also the associated heat lamp.
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The last component for now is the 7" touch display. Since I noticed during the last setup that there are many more setting options that I had not considered in advance. With even more buttons and individual displays, the operation would become confusing. A touch display can guide you through the process much better and thus also be operated much more clearly. It can give hints, make suggestions and automatically complete several tasks at once.
Unfortunately, I have to learn something again to understand the programming. - But I'm thinking positively and therefore believe that I'll get to grips with it. (I always wanted to know how such a display works)..
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I kept my "power supply" for now and just mounted a connector board on my “breadboard”.
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Greetings from Austria
Thomas

[farmersplow]

Breadboard – Electronics
(04 2023)

The provisional bread board has become a large board. Provided are also two Arduino-Mega Board's. On the one hand, because one Mega Board does not have a sufficient number of pins and on the other hand, because one Arduino is not fast enough to do all the tasks.
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Now I just need to make a large number of connectors and connect more cables. Then reprogram everything. But when that is done, then the first device tests and the first test cut can begin.
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Touch Display
(04 2023)

After I learned how to program a touch display, I wrote a provisional software.The data transfer does not run over an I2C interface as I was used to. The I2C interface is an excellent connection between digital components. So all Arduino boards, displays and sensors (IR sensor...) are simply connected via I2C to a node and can then exchange data and information with each other via I2C protocol in all directions and "simultaneously".

The touch display is different.
This is an RX/TX interface. (Rx = Reciever; Tx = Transmitter). It is therefore an exchange of signals in one direction and only between two devices. Element 1 (TX) transmits, element 2 (RX) receives. Then element 2 (TX) can transmit and element 1 (RX) can receive.
So that settings made on the touch display can be processed by both Arduinos, the RX/TX connection to one Arduino must first be established. From Arduino1 to Arduino2 the data must be forwarded via I2C data bus. (It took me a while to understand it this way, but I'm not a professional in this field yet).
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The individual display pages of the touch display are developed using proprietary software and then stored on an SD card. This SD card is then used in the touch display and thus transferred.
All very complex but exciting. I write this only to explain how good I am! (I always have to talk myself into believing it, otherwise I won't manage the next hurdles and challenges).
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Display – provisional

In principle, the operation should be self-explanatory. There is a start page, then "next" and "back" buttons to switch between pages, and a (final) "overview" page. (In the "before" phase some labels are in English and others in German. Planned I have multilingual switchable).

Set for now are:
1. start page
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A Startside.jpg

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2. RECORD
When pressing the "Next" button, the record setting screen will be visible:
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B Record 1.jpg

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The default value suggested is 33.3 rpm and a 12" plate size. (var. = 0 means that the pitch control knob is disabled).

The "expected recording time" (11min 20sec) is displayed in the lower part of the screen.

On the touch display, the plate size can be selected to 12", 10" or 7". (example 10"). This reduces the exposure duration to 7min 37sec).
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B Record 2.jpg

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With a selection of 12" and 45rpm an expected recording time of 8min 28sec is calculated:
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B Record 3.jpg

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Pressing the "Next" button takes you to the "GROOVE" setting.

But there is also an "Expert Mode" button (RED) on this "Record" page. This leads to an "EXPERT MODE" where speed and size can be set more precisely.
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3. RECORD EXPERT MODE
In the Expert mode, in addition to the record speed, the variable speed adjustment can also be set. So the pitch control can be set to +/-8% to adjust the speed with high resolution. But also +/-16% and +/-50% are possible. Thus the platter speed can be doubled or halved max.
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C Record Expert 1.jpg

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C Record Expert 2.jpg

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In addition, the plate size (touchdown point of the cutter head) can also be set to the millimeter in Expert mode. (Display in millimeters and in inches). In the example below, a plate size of up to 14" can be set. This is also practically possible. However, the plate blank protrudes beyond the platter and I don't think the motor will have enough torque to make an excellent cut in that area. If everything else works, I will test it.
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C Record Expert 4.jpg

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4. GROOVE
On this page groove spacing (groove width) and groove depth are set. For my first tests I have programmed the display without "variable groove spacing" (that comes later).
With this "provisorium" the specifications for groove spacing (groove width) are only given in µm (e.g.: 350µm from groove to groove). Later, the measurement for grooves/inch will also be added. 200µm groove spacing corresponds to 127 grooves/inch (if I did not make a mistake in the conversion. But there even NASA has been wrong).
Especially here a change of the expected recording time in connection with the groove spacing can be seen clearly.
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D Groove 1.jpg

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D Groove 2.jpg

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D Groove 3.jpg

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The groove depth can be adjusted from -5 to +5. This reduces or increases the contact pressure. In the provisional version, I have chosen this type of setting because I first have to find out how the contact pressure (grams) is related to the groove depth. Later, I plan to add gram values here as well.
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5. SUCTION and HEAT
On this page three values are set:
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a) STYLUS HEAT.
The heating can be switched off or activated to "Warm", "Medium" or "Hot". The display will then show the current in mA (~190mA; ~250mA; ~400mA). (The heater will only run during recording).
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b) BLANK HEATING
The desired temperature to which the blank is to be heated is set here. The controller then maintains the temperature to within +/-1° (according to the plan). (Also, the blank heater runs only during the warm-up phase and during recording).
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c) EXHAUST
The exhaust can be turned off or activated to "Light", "Heavy" or "Automatic". The suction runs only during the exposure. In automatic mode, it is switched to "Strong" only when the start groove is made, when a pause groove is made, and when the final run-out groove is made. Otherwise, the suction power is reduced. (This is the plan).
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E Suc Heat 1.jpg

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6. CALIBRATION
In advance I have only programmed a control to switch on/off the laser for calibration of the cutting head. Further actions will follow.
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F Calibration 1.jpg

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F Calibration 2.jpg

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7. FILTER & EQ
Also on this page (five) different values are set:
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a). EEQ
With the Elliptical Equalizer the stereo channels are "monoized". This happens up to a selectable frequency of 75Hz, 150Hz or 300Hz.
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b). HIGH-PASS FILTER (Low Cut)
Audio signals below this frequency (20Hz, 30Hz, 40Hz, 60Hz, 80Hz) are filtered. (Butterworth 4th order -24dB analog).
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c). LOW PASS FILTER (High Cut)
Audio signals above this frequency (9kHz, 12kHz, 15kHz, 18kHz) are filtered. (Butterworth 4th order -24dB analog)
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d). IRIAA
Basically IRIAA EQ is activated, but can be deactivated. (IRIAA analog)
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e). Feedback coil closed loop
In principle closed loop is activated, but can be deactivated.
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For the first attempts, the filters and equalizers will remain deactivated and I will only work via digital equalizers (PC and sound card).
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G Filter EQ 1.jpg

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8. TOTAL OVERVIEW
On the last page all settings are shown in summary (here two examples). On the right side of the screen you can go directly to any desired page.
The design is still being changed on all pages, but in this provisional it seems to me sufficiently good.
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H All 1.jpg

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H All 2.jpg

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9. VIDEO - EXAMPLE OF OPERATION
Here I have created another video to show how the operation works
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Video Touch Display.mp4

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Have I forgotten anything important? If you think of something, please write it here. I am still in the phase where I can add a few additions.
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Now the first tests can start. I am already very curious whether everything comes together and the first threads can be cut from the plastic.
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Greetings from Austria
Thomas

[tragwag]

whoa, great work, looks awesome!

[zdenek]

Farmer! That's a lot of work you put into your recording machine!
I came to the conclusion that I won't be able to build a modern machine for recording gramophone records on my own. It's beyond my budget. These are huge costs for me, at the rate I'm doing it will take me years to build a professional machine. That's why I need your help, . .
Will you sell me just the housing for your newest head?
I would like to start cooperation with you, on this forum "The secret lathe trolls". I would like to thank the main moderator, the owner of the website, for giving me access to this trolls community. What do you think about it, Farmer, would our cooperation be possible?

[zdenek]

Bauer! Das ist eine Menge Arbeit, die Sie in Ihr Aufnahmegerät stecken!
Ich bin zu dem Schluss gekommen, dass ich alleine kein modernes Gerät zum Aufnehmen von Schallplatten bauen kann. Das übersteigt mein Budget. Das sind enorme Kosten für mich, bei dem Tempo, mit dem ich arbeite, werde ich Jahre dafür brauchen Baue eine professionelle Maschine. Deshalb brauche ich deine Hilfe, Bauer. .
Verkaufen Sie mir nur das Gehäuse für Ihren neuesten Kopf?
Ich würde gerne die Zusammenarbeit mit dir, , in diesem Forum „Die geheimen Drehtrolle“ beginnen. Ich möchte dem Hauptmoderator, dem Besitzer der Website, dafür danken, dass er mir Zugang zu dieser Troll-Community gewährt hat. Worüber denkst du? Wäre unsere Zusammenarbeit möglich

[whitricketts]

This is incredible! We are super interested in talking about how we can work with you to evolve some of our production / collaborate on some things. Fantastically genius work here, all around. Love to see this technology pushed forward.

[farmersplow]

Nach einer kurzen Unterbrechung geht es nun weiter

Leider hat mich eine schwere Influenza (oder Corona oder so etwas) für zwei Wochen ins Bett gezwungen. Es war mir unmöglich weiter zu arbeiten oder zu posten. So war ich dazu verdammt zu warten bis ich wieder gesund bin – und ich hasse warten. Dabei habe ich weitere 150 Stunden Entwicklungszeit verloren! Aber nun geht es mir wieder besser und ich kann weiter machen.

[farmersplow]

After a brief interruption, I'm now continuing

Unfortunately, a severe case of influenza (or corona or something) forced me into bed for two weeks. It was impossible for me to continue working or posting. So I was condemned to wait until I was well again - and I hate waiting. I lost another 150 hours of development time in the process! But now I'm feeling better again and I can continue.
(sorry, I was still in German-language mode)

[farmersplow]

whoa, great work, looks awesome!

Many thanks for the positive encouragement. As a long-term professional, you've already seen a lot. I'm all the more pleased that you like what I do!

[farmersplow]

Farmer! That's a lot of work you put into your recording machine!
I came to the conclusion that I won't be able to build a modern machine for recording gramophone records on my own. It's beyond my budget. These are huge costs for me, at the rate I'm doing it will take me years to build a professional machine. That's why I need your help, . .
Will you sell me just the housing for your newest head?
I would like to start cooperation with you, on this forum "The secret lathe trolls". I would like to thank the main moderator, the owner of the website, for giving me access to this trolls community. What do you think about it, Farmer, would our cooperation be possible?

It's true, there's already a lot of work involved in the project. But I haven't done anything else for years and my full focus is on completing the Record-Lathe. Of course, the costs already incurred are not to be sneezed at, but I think that if you want something to be good, you can't cut corners when it comes to development time and costs. Compromises must be chosen very carefully and must not reduce the quality.

I have already received a few inquiries about working together. So far, however, all requests have been one-sided, in which I am asked to supply material or know-how. For me, however, a collaboration during the development phase is a collaboration in which everyone contributes and co-develops. One of the reasons why my development is progressing so "quickly" and "evenly" is the fact that I am (so far) able to develop everything myself. This saves me time on coordination and avoids the loss of time that occurs with teamwork. My decades of experience in teamwork have shown me that knowledge can be shared (not everyone has to be able to do everything). Unfortunately, certain tasks are pushed back and forth because no one wants to do them or feels responsible. Things then have to be done twice or three times and coordinated again and again. You can't do anything with the housing alone! What do you want to do with it? What should the "cooperation" look like? In short, if you need 100 cases, then we can talk about it, I will not sell individual cases.
Send me a PM, then we can write about what exactly you need.

[farmersplow]

This is incredible! We are super interested in talking about how we can work with you to evolve some of our production / collaborate on some things. Fantastically genius work here, all around. Love to see this technology pushed forward.

Thanks for the positive words . Send me a PM, then we can write about what exactly you need.

[farmersplow]

First cuts with the new record lathe
(05 2023)

May has begun. My goal was to cut at the beginning of May! And I did it !!!!. The turntable is spinning, the data transfer is working, the platter carriage is moving and all displays are doing what they should. Also the plate heater (version ??? - felt 125) heats. Currently still with infrared lamp, so that I can also visually see what it does.
First function test. The plate carriage has moved to the correct position of the start groove and the plate temperature remains stable at 39°C (+/- 1°).
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The suction tube is well in position and the cutterhead is also correctly adjusted.
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I set my basic settings (as seen on the touch display) as follows:

RPM: 33.3 rpm
Variable speed: 0
Record size: 10”
Record size: 250mm
Groove width: 120µm
Groove depth: +/-0 (currently without connection)
Stylus heat: 315mA
Record heat: 39°C
Suction: Off (currently without connection) (- manual activation)
Laser: Off
EEQ: 300Hz (currently without connection)
Highpass: 40Hz (currently without connection)
Lowpass: 15kHz (currently without connection)
IRIAA: ON (currently without connection)
Feedback: ON (currently without connection)

Calculated max. record time: 12:42
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VIDEO 1:
The platter moves towards the start groove.
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vid1.mp4

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VIDEO 2:
Detail shot at the starting groove. The record blank is not completely flat. This is not a problem for the suction tube as long as the radial runout is not too great.
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vid2.mp4

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VIDEO 3:
The first test cut. Start groove and silent cut. On closer inspection, it can be seen that due to the vertical runout of the record in combination with the "strong" damping of the Dashpot, the cutting graver sometimes cuts too deeply and then again has too shallow a cutting depth.
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vid3.mp4

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I absolutely have to eliminate this error before I carry out further test cuts. Firstly, no sonically meaningful cuts can be implemented this way and secondly, there is a risk of destroying the diamond.

Nevertheless, the joy is great that I have come so far. Now hopefully soon comes the area of the more beautiful work?! (But I'm not so sure, because there is still much to do).

Greetings from Austria
Thomas

[zdenek]

Thanks Farmer!
I would like to buy a head casing from you, if you already have the machines set up, it will be easier and cheaper for you to do it than if I have to design it myself and commission it to a company, I don't have time for that, understand me. Give me an approximate price for your head casing, casing. your head looks like a professional job. I am very impressed with your work and commitment to the project of the vinyl record recorder and your willingness to share theoretical and practical knowledge. It is a beautiful work and I am grateful to you for your contribution to the company of supporters of "the trolls record lathe". I'm looking forward to your next works! Regards!
Danke, Bauer!
Ich würde gerne ein Kopfgehäuse von Ihnen kaufen. Wenn Sie die Maschinen bereits eingerichtet haben, ist es für Sie einfacher und kostengünstiger, dies zu tun, als wenn ich es selbst entwerfen und bei einer Firma in Auftrag geben müsste, das tue ich nicht Nehmen Sie sich Zeit dafür, verstehen Sie mich. Geben Sie mir einen ungefähren Preis für Ihr Kopfgehäuse, Gehäuse. Ihr Kopf sieht aus wie eine professionelle Arbeit. Ich bin sehr beeindruckt von Ihrer Arbeit und Ihrem Engagement für das Projekt des Schallplattenrekorders und Ihrer Bereitschaft, etwas zu teilen theoretisches und praktisches Wissen. Es ist eine wunderschöne Arbeit und ich bin Ihnen dankbar für Ihren Beitrag zum Unternehmen der Unterstützer von „The Trolls Record Lathe“. Ich freue mich auf Ihre nächsten Arbeiten! Grüße!

[farmersplow]

Test cuts with the FP-3 lathe (Farmers Plow Record Lathe No.3)
(05 2023)


The first test cuts are exciting for me, but probably rather boring for you (no music - that comes later). For me, the analysis in advance is much more important because it gives me the appropriate feedback on what is good and what I need to change to become good.

I use the following signal chain for this:

• Test signal (notebook - Cakewalk software) (white noise, pink noise, various frequencies....)

• Digital IRIAA (Cakewalk software)

• No EQ

• From headphone output (on-board soundcard notebook)

• To the power amplifier (Class A/B amplifier - Crown XLi 1500)

• Power amp output to cutterhead

My basic settings on the FP-3:

• Stylus Heat: 335mA

• Record Heat: 38°C

• Groove spacing: 200µm (127 lines/inch)

• Suction: (full load)

• Max. Level of dB display: -3dB (still to be calibrated)

Test cuts 1
(4th May 2023)

The sectional view shows an image of the record:
The groove spacing is 200µm and the groove width is 70µm (slightly too wide).
The test cuts are shown:

• Silent Cut

• 500Hz

• 1000Hz

• 2000Hz

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k 2023_05 groove picture.jpg

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I use the following signal chain for the audio analysis of my test cuts:

• Turntable: JVC QL-Y55F with JVC MC cartridge

• Project Phonobox DS2

• MOTU M2 (Stereo Sound Box)

• PC with Cakewalk software

• Signal analysis with Visual Analyzer 2021 R1 32bit

Test cut 1 - 2kHz
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g 2023_05 2kHz.jpg

Overmodulation of the signal during editing leads to further "artifacts" at multiples of the signal frequency. As a result, "faulty" signals can also be seen at 4kHz, 6kHz, 8kHz and so on. Learn: Do not use signal levels that are too high!

Test cut 1 - 1kHz
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h 2023_05 1kHz.jpg

Same problem. (Learn: Do not use too high signal levels!)

Test cut 1 - 500Hz
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i 2023_05 500Hz.jpg

Same problem. (Learn: Do not use too high signal levels!)

Test cut 1 - Brown Noise
Frequency range 20Hz - 18kHz
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a 2023_05 Brown Noise.jpg

A rarely used test signal. However, it does have its justification.

Test cut 1 - White Noise
Frequency range 20Hz - 18kHz
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b2 2023_05 White Noise.jpg

A frequently used test signal. However, it involves the risk that the driver coils may be overstressed at high frequencies. However, it shows the main and secondary resonances well.

Test cut 1 - Sweep 20Hz – 18kHz
Frequency range 20Hz - 18kHz
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c 2023_05 Sweep 20Hz - 18kHz.jpg

In principle the same as white noise, but instead of playing all frequencies at the same time, the frequency is slowly increased from 20Hz to 18kHz.

Test cut 1 - Sweep 20Hz – 16kHz
Frequenzbereich 20Hz – 16kHz
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d 2023_05 Sweep 20Hz - 16kHz.jpg

I carried out the test with different cut-off frequencies to check to what extent the secondary resonance (above 10kHz) is formed. Does it arise from "artifacts" of lower frequencies or are they actually resonances of the geometry and actually arise at 12-, 14- 16kHz?

Test cut 1 - Sweep 20Hz – 14kHz
Frequenzbereich 20Hz – 14kHz
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e 2023_05 Sweep 20Hz - 14kHz.jpg

Analysis: They actually occur at 12-, 14- 16kHz

Test cut 1 - 60Hz & 7kHz
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f 2023_05 60Hz and 7kHz.jpg

Here is a test cut performed simultaneously at 60Hz and 7kHz.

Test cut 1 - Analysis

Am I happy? - NO!

• The silent cut is way too loud

• The main resonance is at 700Hz (my target is above 1kHz)

• There is "turbulence" at 2kHz

• Inconsistencies at 11kHz

• secondary resonances at 16kHz

• In addition, the drive of the stepper motor can also be heard in the range around 60Hz

• A loud "noise" with every turn of the platter

Am I unhappy? - NO!
If everything was perfect now, I wouldn't know why!
I can now start to analyze and investigate the causes. In doing so, I will come across changes that will show me what needs to be done to develop a really good cutting head and what it takes to build a good record cutter.
I am realistic about this and did not expect a perfect head. But the results are not bad either. After all, this first attempt is no worse than the best development stage of my last head. Only more stable! Because a fabric spider soaked in epoxy resin to make it harder is a nice piece of development research, but not a permanent solution for a functioning cutting head. The aluminum spider is much more stable and reproducible.
The loud noise during the silent cut came from the new diamond stylus. In the meantime, I have realized that I have to cut one or two record sides before the stylus becomes quieter.
Now I just have to make it better. But this requires further tests.

Greetings from Austria
Thomas

[Thelatheofus]

Once again this is incredible ! Thank you for taking us along in your journey. This is a dream setup, have fun tweeking it !

[zdenek]

How do you implement variable turntable slide travel and knife pressure with synchronization of the delayed audio signal?
What I mean is that the support has time to position itself in the right place before the sound so that the knife does not enter the adjacent recorded groove, as is done in German machines with the Studer A80 tape recorder, as it is done professionally, one head first gives the signal to servo of the head support mechanism and then about a second later, at 33rpm, the second reading head of the tape recorder sends a signal to the cutting head. What delay computer program do you use, or do you use a tape recorder with two reading heads?

1280px-STUDER_A80_Master_2_Track_Recorder,_Mastering_Version.jpg

[farmersplow]

Once again this is incredible ! Thank you for taking us along in your journey. This is a dream setup, have fun tweeking it !

I'm sure I'll have a lot of fun with tweeking. There are people who love listening to music on record players. And then there are those who spend 90% of their time adjusting the platter, setting the cartridge, checking the tension of the drive rubber, improving tracking etc.! I belong to the second category. Of course I like listening to the records too, but the tweeking is all mine.