A few months back, I wrote about how I used a 3D printer to transform any mp3 into a physical record.  Though all the documentation for that project is available here, and the 3D models could potentially be printed through an online fabrication service, I knew that the barrier to entry for normal people interested in trying out the process themselves was prohibitively high.  With this project I wanted to try to extend the idea of digitally fabricated records to use relatively common and affordable machines and materials so that (hopefully) more people can participate, experiment, and actually use all this documentation I've been writing.

These records were cut on an Epilog 120 Watt Legend EXT to a theoretical precision of 1200dpi (the kerf of the cut and some tricks I used to avoid crashing the laser cutter dropped the actual precision down by ~1/6).  The audio on the records has a bit depth between 4-5 (typical mp3 audio is 16 bit) and a sampling rate up to about 4.5kHz (mp3 is 44.1kHz).  So far I've successfully cut audio on wood (figs 1-2), acrylic (figs 3-4), and paper (figs 5-6), and I'm sure there are many more materials that would work.  I wrote the Processing sketch that generates the record cutting paths so that it can be modified for any song, material, cutting machine, record size, and turntable speed (skip ahead to download the code and learn how to make your own records).

You should also note that in this Instructable I'll demonstrate specifically how I used a laser cutter for this process, but the cutting files I'm using are standard vector graphics in a PDF format, so they can be extended to many other digital fabrication tools. For example, I'm curious to see if it's possible to use a CNC mill or a CNC razor blade paper cutter with my cutting files (a group of people were able to cut out some sine waves on paper using a Cameo in this Instructable).

Below are some of my final results, read on to see how they were made and how you can make your own.

Joy Division - Love Will Tear Us Apart on clear acrylic (download vector files):

Radiohead - Idioteque on wood (download vector files):

The Velvet Underground and Nico - Femme Fatale on maple (download vector files):

Step 1: How Does a Record Work?

I've explained a bit about how a record works and the scale of vinyl microgrooves in my 3d printed record project.  The main difference between these laser cut records and my 3d printed records is the axis that the grooves are cut on.  Since I can't control the power of the laser while it is cutting a vector path, the laser cut records are cut laterally on the surface of the material.  This means that the needle only vibrates in the plane parallel to platter of the turntable.  The 3d printed records are "cut" vertically, meaning the needle vibrates in the plane perpendicular to the platter.  I chose to modulate the grooves vertically for the 3d printed records because the vertical axis is the most precise axis on the machine (resolution of 16 microns).

Stereo (2 channel) vinyl records are cut both vertically and laterally, this way it's possible for two isolated channels of audio to fit into one groove.  Mono vinyls are cut laterally only, this is because the vertical cuts can become distorted, especially if you try to increase the amplitude of your waveform to increase the dynamic range of the sound.  Although I didn't really have a choice in the matter, it's better to to cut a mono groove laterally.

To give you an idea of the size of the grooves on a modern record, check out the image above from Chris Supranowitz, a researcher at The Institute of Optics at the University of Rochester.  This is a close up image of a vinyl record, taken with an electron microscope.  The dark objects in the grooves are tiny particles of dust.  The laser cutter cannot make such precise cuts because the width of the beam is too large, so the grooves on my records are about 1-2 orders of magnitude larger in every dimension than these grooves.

Step 2: Laser Cutter Specs

The lasers in our office are Epilog 120 Watt Legend 36EXT.  They have a 36"x24" cutting bed, big enough to cut several 12" records at a time.  They have a max resolution of 1200dpi in the x and y axes and 100 power and speed settings to control cutting depth.

Before I started cutting anything, I used these numbers to calculate the resolution I'd be able to achieve.  First I wanted to make sure that I would be able to get a good sampling rate on my audio.  Sampling rate is the amount of samples per second in a song.  Usually the sampling rate is 44.1kHz (or 44,100 samples a second).  When the sampling rate drops below about 40kHz the higher frequencies of a song start losing their detail, but depending on the song you can go down to 20 or even 10kHz sampling rate without too much of a problem.

To calculate the sampling rate, I used the following relationship:

sampling frequency = (resolution per inch)*(inches per revolution)*(revolutions per second)
(in order to maximize the sampling frequency, we want all of these numbers (res/inch, inch/rev, rev/sec) to be as high as possible)
also notice how the sampling rate will decrease as the needle moves towards the center of the record (smaller inches/revolution)

First I'll start with revolutions per second.  Record players typically play at two different speeds: 33.3 and 45rpm.  (Some record players also have a 78rpm speed, but this is less common and only used for very old records).  If I use the higher, 45rpm speed I can calculate revolutions per second as follows:

revolutions per second = (revolutions per minute)/(seconds per minute)
revolutions per second = 45/60 = 0.75

Next is inches per revolution, this number depends on the circumference of the disk where the needle is hitting it. The largest sized records are 12" in diameter (30cm).  According to the RIAA standards, the outermost groove of a 12" record falls at a radius of 5.75" and the innermost groove falls at about 2.25".  I'll use these numbers to determine the range of sampling rates I can achieve at 33 and 45rpm.  The circumference (the distance in inches traveled by the needle during one revolution of the record) is calculated as follows:

inches per revolution = 2*pi*(radius of needle)
max inches per revolution = 2*pi*5.75 =~ 36
min inches per revolution = 2*pi*2.35 =~ 15

We already know that the resolution per inch of the laser cutter is 1200 (1200 dpi  in the x and y axes).  So combining this all we get:

sampling frequency = (resolution per inch)*(inches per revolution)*(revolutions per second)
max sampling frequency at 45 rpm = 1200*36*0.75 =~ 32400 = 32.4kHz

min sampling frequency at 45 rpm = 1200*15*0.75 =~ 13500 = 13.5kHz

This is a pretty good starting point.  If I scale this to 33.3rpm instead of 45 (this will allow me to fit more music on the record) the sampling rate becomes:

max sampling frequency at 33 rpm = 1200*36*0.5 =~ 21600 = 21.6kHz
min sampling frequency at 33 rpm = 1200*15*0.5 =~ 9000 = 9kHz

This is still easily enough to reproduce a recognizable song.

The next thing that I needed to think about was the bit depth.  Bit depth is the resolution of the audio data.  Most audio these days in 16 bit, meaning each sample can have one of 65536 (2^16) possible values.  8 bit audio has only 256 (2^8) steps of resolution and still sounds pretty close to the original.  (Music that is commonly referred to as "8-bit" like the music in early Nintendo games is actually 1 bit resolution, this low resolution is what gives it its unique and instantly recognizable sound, but I'm aiming for something that sounds a little more organic).

As I said in the last step, the grooves on these records are cut laterally.  The following equation calculates the horizontal distance that the needle will move as it traces the a wave of a given bit depth:

horizontal displacement of needle = (2^bit depth)*(precision of x/y axes)
where the precision of the x and y axes is 1200dpi or about 21 microns.  I used this to calculate the following table:

bit depth          horizontal displacement                steps of resolution

     2                             84um                                          4
     3                            168um                                         8
     4                            336um                                        16

     5                            672um                                        32
     6                          1.344mm                                      64
     7                          2.688mm                                     128
     8                          5.376mm                                     256

The bolded rows in the table are the numbers that I wanted to shoot for with this project.  Although a horizontal displacement of about 0.5mm is quite large compared to a normal record, I think somewhere in that range will work.

Step 3: Sine Tests

As with my 3d printed records, I started off by printed out some sine wave tests to get an idea of what kind of frequency range I can achieve and to test out some parameters (laser power, cutting speed, material, wave amplitude).  I used Processing to generate sinusoidal paths and cut these first tests on white 3mm acrylic.

Here's the Processing code I used:

and here's a video of the results:

(the 139hz sine wave may be too low to hear with laptop speakers)
I was really happy with these first tests.  These is some noise in the background, but it's very consistent and the signal to noise ratio is pretty good.  Amplitudes of 4 and 6 sounds good across the frequencies tested here, as the frequency gets higher, you can hear a good amount of distortion on the amplitude 8 wave.

Different lasers and brands of laser cutter will respond differently, but this record was cut at 5000 freq with 100 speed (although the cutting head was moving very slowly due to the density of points on my vector path) and 12 power (enough to etch the surface but not to cut all the way through).

Step 4: Audio Tests on Acrylic

I did a ton of sine tests for my 3D printed record, but I was anxious to launch into the audio for this much sooner so I just went for it.  Even though on some level I knew this would be a bit of a disaster, here's my first attempt with audio:

The song is Love Will Tear Us Apart by Joy Division.  My favorite of all the records I 3d printed was definitely the Joy Division one (the song Disorder), I like the creepy vibe the distortion gives it.

This laser cut joy division track is not quite there yet (though decently recognizable).  You can hear a lot of crunchiness on the drum beats, if you could look closely at the record, you would see that these areas of high frequencies were melted into oblivion by the cutter.  In this attempt I didn't make any effort to set a max frequency of the cuts, and the tighter cuts required by these sections apparently caused the laser to linger too long on the material.

I learned some things about the laser cutter from this attempt.  The first couple of tries I made on this cut caused the laser to freeze up almost immediately.  At first I thought I was overloading the machine with data, but then I realized that the machine does not like to receive extremely dense vector paths.  In fact, I found that if two points on a vector path are within about 6 pixels of each other, the laser will quit.  I had to amend my code to account for this.  Here is the Processing code I used:

As with the 3d printed record, I pulled the raw audio data from the original wav file using Python before sending it to Processing, that code can be found here.  And again, if someone knows a way to bypass this step, please feel free to leave a comment, I would much rather keep everything in Processing.

In my next test I set a limit on the angular distance between consecutive points, hoping to minimize melting of the material.  Here's the code:

   if(((xValLast-xVal)*(xValLast-xVal)+(yValLast-yVal)*(yValLast-yVal))>(minDist*minDist) && radCalc*abs(thetaLast-theta)>minAngDist){
        //store last coordinates in vector path
        xValLast = xVal;
        yValLast = yVal;
        thetaLast = theta;

...and the video:

The cut came out much cleaner, and you can hear significantly less distortion on the audio, but I thought I could still make it better.  In the next test I set the samples per revolution to a constant number (6000) and removed the minimum angular distance logic from my code.

At 6000 samples per cycle the sampling frequency of the audio is:

samples/sec  = samples/rev * rev/min * min/sec
samples/sec  = 6000 * 45 * 1/60 = 4.5kHz

Here's the code:

and the video:

Though it's a little hard to hear because of all the skipping, the cut came out much cleaner on this test.  You can also hear that the audio sounds slowed down, this was a rounding issue in my code that I dealt with later.  In my next test I decreased the amplitude of the wave to 12px to see if I could get the needle to stay in the groove.

    float amplitude = 12;

There are still a few issues.  Most notably, the record is warped from the cutting process.  Also the speed of the audio is still screwed up.  In my final version I fixed the speed issue (it was a rounding problem) and tried taping the acrylic down to the bed to see if that would help with the warping.  The settings I used on the laser cutter are:

laser settings (epilog 120W)
100 speed
12 power

In this cut I actually applied the proper RIAA equalization as well and used an anti-aliasing low pass filter of samplingRate/2 = 2.25kHz.

Here is the final code:

and the final product:

There was still some warping, but the tempo issues are completely resolved.  It's interesting to hear how much the audio quality degrades from the outside of the disk to the middle of the disk - this is due to lowered surface speed of the record as you move toward the center (explained in step 2).

Step 5: Audio Tests on Paper

Next I tried this out with paper, first I used a sheet of thicker black (almost cardstock) paper.  I used the song rebel rebel as my test.

The settings on the laser were as follows:
speed 100
power 4
frequency 500

The resulting records looked great (see image above), and you can even hear the song coming through, but it had a lot of trouble with skipping:

So I picked up some new paper, this time it was much thicker, almost like thin cardboard.  I did some sine tests and found that setting the laser power to 7 was the deepest I could cut without going through the paper.  Then I did another test of rebel rebel, this time cut at 7 power and with the amplitude of the wave lowered to 10 (from 12).  The needle still will not stay in the groove by itself:

I also tried defocusing the laser from the paper to widen the cut (still at amp 12).  The inner cut is more defocused than the outer, notice how the needle is more stable, but the audio quality is lower.

Since the defocusing seemed to be the only way to keep the needle in the grooves, I tried defocusing the laser by reproducible distances to find the perfect balance between needle stability and low noise.  To do this I placed anywhere from 4 to 16 pieces of white printer paper on top of the cardstock while I ran the laser's autofocus.  This meant that the focal point of the laser would actually be a fraction of an inch above the surface of the cardstock.  That test is shown below, the outer rings are defocused by 4 sheets, the next 7, 10, 13, and 16 sheets.

I concluded that about 10-12 sheets defocused was the absolute minimum needed to keep the needle stabilized in the groove.

Step 6: Audio Tests on Wood

Finally, I cut some records on wood.  Eventually I'd like to cut a record on a 12" wood round with a raw edge, kind of like this, you could cut the grooves right onto the rings of the tree.  For now I have some nice maple sheet to cut, but I did my firsts tests on ply.  I started by using similar settings that I used on the acrylic:

power = 12
speed = 100
freq = 500
amp = 12

This cut looked great, but the needle skipped a lot, I had to hold it in place to shoot this video.  I went back and did some sine wave tests and found that 15 power was more stable, so I ran another audio test at 15 power:

This cut was much more stable, but skipping was still an issue, you can also hear the same tempo issues I was having with the acrylic (I was cutting all these records at the same time).  Next I tested lowering the amplitude of the cut to 10:

I also tried defocusing the laser to widen the groove, keeping the amplitude at 12.  The outer groove is slightly defocused, the inner grove is more heavily defocused:

Both defocusing and lowering the amplitude of the cut helped to minimize skipping, but the defocusing introduced more noise into the audio.  For my final plywood test I lowered the amplitude to 10 and kept the laser focused, I also fixed the tempo issue in my code.  Here is the result:

Unfortunately at this point I was using the last of our plywood stock, so I couldn't be too picky about how flat the ply was, but it still (surprisingly) plays fine(ish).  Here's the code I used:

Next I used the maple.  Fortunately, noahw helped me track down a 13" wide curly maple board and cut it into a two flat sheets: one was about the thickness of a real vinyl record at about 1/16" and other a little thicker at 1/8".  I sanded the maple sheets to about 1500grit and finished them before cutting.  I did a few tests on a piece of scrap and found that the power setting I was using on the ply was cutting so deeply into the maple that I would not be able to cut both sides.  I did a few more experiments with defocusing and actually did a full attempt using the song sunday morning by the velvet underground:

In this test I defocused the laser by the width of 11 sheets of normal printer paper.  I used the following laser settings:

power = 4
speed = 100
freq = 500
amp = 10

This cut came out a little noiser than I was hoping.  Since the needle wasn't having any issues staying in the groove, I defocused by only 9 sheets of paper and kept the same power settings.  On the other side of the sunday morning disc, I cut femme fatale:

While I was adjusting some tape to try to keep the wood lying flat in the middle of the cut, I accidentally bumped it to the side slightly.  If you look closely at the video, you'll see where the error is, it caused the needle to skip a groove, but other than that the cut came out great.

This song helped me pin down an error in my code, if you listen closely during the chorus, you'll notice that the backing vocals are missing.  When I looked back at the song, I noticed that the vocals are only found in the left channel of the track, so it seems that I was not combining the two channels before converting to a vector file.  I think I've fixed the problem in my python script, but I'll have to run a test to know for sure.  In the meantime, you can work around this problem by importing your stereo audio into Audacity, right clicking on the track and selecting "split stereo to mono", saving the file as a wav, opening that saved file in Audacity again, copying the track, and right clicking on each of the duplicate tracks to set one to left channel and one to right channel.

Step 7: Make Your Own

You can convert your own audio files into vector cutting paths in ten easy steps:

1.  Download Processing.

2.  Download Python 2.5.4.

3.  Download Audacity.

4.  Download the code from GitHub (you can download the zip file by clicking on the cloud button).  Unzip and open the folder called LaserCutRecord.

5.  Open an audio file of your choice with Audacity.  Go to Effect>Equalization and select RIAA.  Hit inverse and apply, you should now hear the higher frequencies of your track boosted.

6.  Go to Effect>Low Pass Filter... and apply an anti-aliasing filter (a fancy word for a low pass filter) to your audio.  You will have to choose the cutoff frequency according to the max sampling rate that you can get with your cutter.  For example, my laser cutter melts anything above 2.5kHz at 45rpm, so I set my anti-aliasing filter cutoff to this same frequency.  Set the drop off as high as possible, for me this was 48dB/octave, that way the filter will have a hard cutoff.

7.  Use Effect>Amplify to amplify the signal as much as you can without noticeable effects of clipping (you will be able to get away with some clipping, and remember this is not crystal clear audio anyway). You may also want to mess around with Effect>>Compressor.

8.  Make sure there are 2 sec of blank audio at the end of the track so that nothing gets clipped and keep the audio under 3:10.  File>Export this file and save it in the "LaserCutRecord" folder as a wav file. 

9.  Open the Python file called "wavtotxt".  Copy the file name of the file you just saved in the line:

             fileName = "your_file_name_here.wav"

Hit Run>RunModule, after a minute or two you will have a .txt file saved in the Record Generator folder.

10.  Open the Processing sketch.  Change the name of the import file in the Processing sketch to your txt file name:

             String filename = "your_file_name_here.txt";

Run the Processing sketch Sketch>Run.  The Processing sketch will output several files, none larger than 700KB (I found that larger files were crashing the laser cutter).  The last file will also contain the cut paths for the inner hole and outer edge of the record, you will need to set your laser cutter to cut these lines at a higher power, so that it cuts all the way through the material.  Another very important note about cutting these files - the reason I had to split each song up into five parts is because I found that files larger than 800KB would crash my laser.  When you are cutting out the sequential files, you MUST shut down the laser for a second to clear it's memory and then turn it back on before sending it a new 700KB file to cut, you will have problems if you forget this.

Once you've made cutting files, post them!  You can upload files in the comments by clicking on "Rich Editor."  Enjoy, and let me know if you have questions or need help getting this to work.  I've tested this process Mac OS using the latest version of Processing.  If you actually end up cutting your own record, please post the results in the comments, I'm really curious to see where this code ends up!

In case you are stuck trying to find a machine to cut your files, check this list of worldwide hackerspaces, these are places where anyone can go for little to no money and use tools in a collaborative work environment.  If you are in school, you might ask the engineering or art departments if they have a machine than can cut vector files.  Otherwise, I'd recommend checking out an online fabrication service such as Ponoko.  Some people even build their own laser cutters, there are many builds documented right here on Instructables, we're even giving one away in our Epilog Challenge.
<p>hi amanda, hi community</p><p>attached you see two screenshots from the same .pdf. the more complete looking one is preview/acrobat the smaller one comes from illustrator. anybody? solutions or explainations? </p><p>hugs</p><p>cc</p>
<p>Hey,</p><p>Just wanted to pin this comment to the top since lots of people are running into it. the problem is that illustrator doesn't like to import so much data at once, so it cuts it off. You need to break your data into smaller chunks to import.</p><p>If you look at the processing code:</p><p><a href="https://github.com/amandaghassaei/LaserCutRecord/blob/master/LaserCutRecord.pde">https://github.com/amandaghassaei/LaserCutRecord/b...</a></p><p>there's a variable called </p><p><strong>numGroovesPerFile</strong></p><p>lower this number so that you export more files with fewer grooves on each (maybe 7 is a good place to start, but you may need to go lower). Once you make the chunks of data small enough, you will be able to import the files into illustrator without loosing anything.</p><p>Hope that helps!</p>
hi amanda, <br><br>thanks a lot. i reuced the numgroovesperfile down to 5. it worked now. couldn&acute;t believe it. thanks for pointing out the importance of it.<br><br>will post the results here soon.
<p>Hi Amanda, (in regards to the laser cut record project) I'm having some trouble because when I send the files to be cut on the laser cutter, the laser cutter messes up. Is there any reason why this is happening?</p><p>Thank you.</p><p>Kind regards</p>
You'll have to be a little more specific, what does "messes up" mean? Can you upload a photo?
Sure, sorry heres two test ones I ran. The first one came out the way it should until it got to the end and thats the black record. The white-ish record just messed up from the start, it wouldn't cut the circle properly.
<p>wow I've never seen this before. what model is the lase cutter? Maybe try increasing the number </p><p>minDist </p><p>to 8 or 9 and see if that does anything. It's at the top of this file:</p><p><a href="https://github.com/amandaghassaei/LaserCutRecord/blob/master/LaserCutRecord.pde">https://github.com/amandaghassaei/LaserCutRecord/b...</a></p><p>that will space out individual points on the vector path a little more. I found that if they were too close together my laser would just stop. The behavior you're seeing is very strange, but maybe related.</p>
Sure, sorry I'll attach the photos. I did two test runs with the velvet underground song, the first one (black record) was fine up until the end when stopped following the vector paths. The second test was with the white-ish material, the laser cutter didn't even cut the circle right from the start. Pictures are attached :)
I'm having a bit of an issue running the processing sketch. <br> <br>Processing crashes when I load the split strings into this array. My .txt file is 43mb. Which seems gigantic for a plain text. But at 44100 x 180~ sec. I guess that makes some sense. <br> <br>it's this line that causes the sketch to run out of memory. I've changed my processing prefs to allocate 512MB but it still crashes. I suppose I'm confused, or not doing something right, as no one else has posted this issue... <br> <br> float audioData[] = float(split(rawDataString,',')); //separated by commas <br> <br>any thoughts?
<p>Having the same issue with roughly the same size txt file, the original song was 3.10 minutes long. Can anyone give me any tips on what i'm doing wrong?</p>
<p>can you post the text file? click on "add images" when you leave a comment, it will let you upload a file.</p>
<p>interesting, I haven't seen that one before. can you upload your txt file? (use the "add images" button)</p>
<p>Does anyone have any suggestions for making a straight line (instead of a circular record shape) with this? </p>
<p>Just put in an empty sound file, that should work. The sound waves are made by the &quot;wiggles&quot; so anything with no sound would just be a regular curve.</p>
<p>Oh, no, sorry for the confusion - I meant, I'd like to take the audio and plot it along a straight line, rather than curved as a record..Is it possible to do that with this Processing code? I'm not very good with equations..</p>
<p>put this code and the attached files in the same folder and run it in processing. You'll probably want to play around with xScale depending on how fast you want to read the audio.</p><p>import processing.pdf.*;<br><br>//parameters<br>String filename = "casbah.txt";//generate a txt file of your waveform using python wav to txt, and copy the file name here<br>float samplingRate = 44100;//sampling rate of incoming audio<br>float dpi = 1200.0;//dpi of cutter<br>int cutterWidth = 100;//width of laser cutter bed in inches<br>int cutterHeight = 5;//height of laser cutter bed in inches<br>float amplitude = 5.0;//in pixels<br><br>float xScale = 1.0;//in pixels<br><br>void setup(){<br> <br> float[] songData = processAudioData();<br> <br> float scaleNum = 72.0;//scale factor of vectors (default 72 dpi)<br> amplitude = amplitude/dpi*scaleNum;<br> xScale = xScale/dpi*scaleNum;<br> <br> size(int(cutterWidth*scaleNum),int(cutterHeight*scaleNum));<br> <br> <br> //change extension of file name<br> int dotPos = filename.lastIndexOf(".");<br> if (dotPos &gt; 0)<br> filename = filename.substring(0, dotPos);<br> <br> <br> float x = 0;<br> <br> beginRecord(PDF, filename + ".pdf");//save as PDF<br> background(255);//white background<br> noFill();//don't fill loops<br> strokeWeight(0.001);//hairline width<br> <br> beginShape();<br> int i;<br> for (i=0;i&lt;songData.length;i++){<br> x = i*xScale;<br> if (x &gt; cutterWidth*scaleNum) break;<br> vertex(x,cutterHeight/2*scaleNum + amplitude*songData[i]);<br> }<br> <br> println("sample " + i + " of " + songData.length);<br> println(i/float(songData.length)*songData.length/samplingRate + " seconds of " + songData.length/samplingRate + " fit on this pdf");<br> <br> endShape();<br> endRecord();<br> <br> exit();<br> <br> //tell me when it's over<br> println("Finished.");<br><br>}<br><br>float[] processAudioData(){<br> <br> //get data out of txt file<br> String rawData[] = loadStrings(filename);<br> String rawDataString = rawData[0];<br> float audioData[] = float(split(rawDataString,','));//separated by commas<br> <br> //normalize audio data to given bitdepth<br> //first find max val<br> float maxval = 0;<br> for(int i=0;i&lt;audioData.length;i++){<br> if (abs(audioData[i])&gt;maxval){<br> maxval = abs(audioData[i]);<br> }<br> }<br> //normalize amplitude to max val<br> for(int i=0;i&lt;audioData.length;i++){<br> audioData[i]*=amplitude/maxval;<br> }<br> <br> return audioData;<br>}</p>
<p>just added it to the repo too:</p><p>https://github.com/amandaghassaei/LaserCutRecord/blob/master/LinearRecord.pde</p>
<p>Oh Wait did you mean a line that isn't curved at all? This guy printed this with a laser engraver, so if you don't have a laser engraver, you can't cut or etch anything. A laser printer can easily engrave a straight line, usually all you have to do is draw a straight line on a computer, adjust the print settings and print it to the engraver</p>
<p>No, I mean I'd like to take the audio signal modulation and print it in consecutive lines, rather than curving the grooves around a record shaped disc.I have a laser engraver. </p>
<p>Like this - except spec'd for record player groove size. </p>
<p>Hi Amanda, I just sent you an e-mail regarding a film shoot inquiry. Can you please check your gmail and let me know what you think? Thank you~</p>
<p>hi amanda!<br><br>i have the same problem with the pdf files not matching properly. The preview and the acrobat reader/pro show me the exact turns and geometries. but when opening in an vector editing program such as illustrator or rhino a certain part doesn&acute;t show up. so the bit&acute;s don&acute;t fit. can you tell why?! and what to do? thanks a lot and much respect for this incredibly easy and understable manual! </p>
<p>Hi Amanda, I've run the code through Python 2.5.4 and it is saying there is a syntax error. Here is the code I'm running:</p><p>import wave</p><p>import math</p><p>import struct</p><p>bitDepth = 8#target bitDepth</p><p>frate = 44100#target frame rate</p><p>fileName = &quot;FemmeMono.wav&quot;#file to be imported (change this)</p><p>#read file and get data</p><p>w = wave.open(fileName, 'r')</p><p>numframes = w.getnframes()</p><p>frame = w.readframes(numframes)#w.getnframes()</p><p>frameInt = map(ord, list(frame))#turn into array</p><p>#separate left and right channels and merge bytes</p><p>frameOneChannel = [0]*numframes#initialize list of one channel of wave</p><p>for i in range(numframes):</p><p> frameOneChannel[i] = frameInt[4*i+1]*2**8+frameInt[4*i]#separate channels and store one channel in new list</p><p> if frameOneChannel[i] &gt; 2**15:</p><p> frameOneChannel[i] = (frameOneChannel[i]-2**16)</p><p> elif frameOneChannel[i] == 2**15:</p><p> frameOneChannel[i] = 0</p><p> else:</p><p> frameOneChannel[i] = frameOneChannel[i]</p><p>#convert to string</p><p>audioStr = ''</p><p>for i in range(numframes):</p><p> audioStr += str(frameOneChannel[i])</p><p> audioStr += &quot;,&quot;#separate elements with comma</p><p>fileName = fileName[:-3]#remove .wav extension</p><p>text_file = open(fileName+&quot;txt&quot;, &quot;w&quot;)</p><p>text_file.write(&quot;%s&quot;%audioStr)</p><p>text_file.close()</p>
<p>does it say what line?</p>
Thank you for your reply! I fixed the problem, how thick was the wood that you used for the record?
<p>doesn't really matter, I used 1/8 to 1/4". as long as it's pretty flat and stays flat it should be ok.</p>
<p>I keep getting unterminated string constant</p>
<p>are you missing a closing double quote on your filename variable?</p>
<p>which line? and what version of processing?</p>
<p>For the 3d printed version, have you tried printing a blank record and then recording onto it as a baseline for potential audio quality? If so, how did it turn out?</p><p>Have you tried any additional materials since? Perhaps wax? I'm looking into replicating old edison wax tubes as a side project. :)</p>
<p>I've thought about that, but the geometry of the streaks that cause the noise is different on every print, so I think you would only add more noise by trying to correct for it. I'm going to do a text in a few weeks milling a record, on brass I think.</p>
<p>Awesome.. Will be great for personal records. :)</p>
<p>Hi , I thought I was original changing the diamond tool by a Laser one to cut the viny!!!.....I am subscribed to &quot;INSTRUCABLES&quot; and decide to look here for a transducer sound-mechanical.....and I ve found &quot;my&quot; Idea hahaha......Ideas are on air ....ok Congratulations.<br><br>However I am involved in laser cutting /gravure of surface for automation in machines , these grooves must be read by an electronic eye , we move to the laser a year ago ( we use tu use Copper and cnc with diamond tool), in our experience you can get great results with engraving Polyimide ( warning: Not Polyamide) ....is Thermoset and stands high temperature , and the cut is very very precise and without the tipycal deformation of thermoplastics at High temperature, , the scrap is just a fine powder that you can remove with a brush, colors in the market are ambar and Black.</p>
<p>im getting an error on python:</p><p>Traceback (most recent call last):</p><p> File &quot;/Users/eidtecnico/Downloads/LASER RECORDS/LaserCutRecord-master/LaserCutRecord/wavtotext.py&quot;, line 26, in &lt;module&gt;</p><p> frameOneChannel[i] = frameInt[4*i+1]*2**8+frameInt[4*i]#separate channels and store one channel in new list</p><p>TypeError: 'map' object is not subscriptable</p><p>&gt;&gt;&gt; </p>
<p>did you put the audio file in the same folder as the python script?</p>
<p>Hello! I'm also getting the same problem when I run the file in Python 3.4.1. When I run the file in Python 2.7.8 it says </p><p>Traceback (most recent call last):</p><p> File &quot;/Users/flaviawilson/Desktop/UNIVERSITY/CCDN244 Expanded Photographics/Project Two - Lomo/LaserCutRecord-master/wavtotext.py&quot;, line 26, in &lt;module&gt;</p><p> frameOneChannel[i] = frameInt[4*i+1]*2**8+frameInt[4*i]#separate channels and store one channel in new list</p><p>IndexError: list index out of range</p><p>Do you have any ideas? The audio file is definitely in the same folder as the python script. Sorry to be a bother, I'm new to python but super excited about this instructable! You've done an awesome job, thanks so much :)</p>
<p>Figured out the problem - I'd already converted the audio track to mono, so the python code was getting confused because it was thinking the track was in stereo.</p><p>Also the code does only seem to work in 2.5.4, but I might be wrong.</p>
<p>Thanks! Stereo Mono issue solved it. </p>
<p>cool, yeah I haven't tested other versions.</p>
<p>use 2.5.4. I tried using other python releases as well and they didnt work</p>
<p>I am confused on step 10 what do I rename in processing?</p>
<p>if your text file was called mySong.txt then you should change the line to:</p><p><strong>String filename = "mySong.txt";</strong></p>
<p>the name of your song, the text file to import.</p>
<p>hi there - when you say the track length must be 3:10 is this minutes or hours? many thanks! stephen</p>
<p>I am a E.E. with a background in audio -including phonograph lathing. Wow. Now, why did I not think of lasers? Actually, RCA DID think of lasers back in the early 1980s to cut digital laser-disks for video (3.5 mHz bandwidth!). And they worked beautifully (with hi-fi and resolution higher than of USA TV)! Unfortunately VCRs were a good deal cheaper (for consumers), but the RCA disk system had a life in network TV for slow-motion playback in sports. Tape with flying heads had a lot of distortion and jitter (back then), but disks were great.</p><p>As for your wonderfully clever wood records...try using African Ebony as it will yield better resolution than maple. However, it is difficult to cut. (It is more like metal than wood!).</p><p>Keep the old noodle (needle?) working -you are a clever young person and the world needs such people DESPERATELY. Brains that lead emotion and ego are refreshing. God Bless.</p>
<p>Just like playing Beatle records backwards...this is a GREAT way to screw up your stylus! Just don't use it on a Shure V-15 xVMR! -Please! </p>
<p>Very nice liked. I hope you the further development.</p>
<p>I'm wondering whether you think the quality could be improved with <a href="http://www.mydiycnc.com/content/mydiycnc-desktop-cnc-machine" rel="nofollow">this machine</a>, which is listed as 4000 steps per inch (or 32000 with an upgrade), compared to 1200 with the laser you used.</p><p>Is that the main factor that would be involved in improving quality? What other factors would you consider?</p>
<p>not really, the issue is that the width of the cut is pretty large and the finish is not so smooth, so the needle is getting bumped around quite a bit as it plays.</p>

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Bio: I'm a grad student at the Center for Bits and Atoms at MIT Media Lab. Before that I worked at Instructables, writing code for ... More »
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