KVR Audio

nix808 · Post by **nix808** » Wed May 11, 2011 8:41 am

Hey,
I thought I'd share this, as I think it's cool.
If you have an old HDD(hard disk drive) lying around,
it's quite easy to turn it in to a turntable controller to scratch on.

I have software I can share that decodes the signal and drives a track,
so if you are keen hit me up. I will post the beta version in this thread.
What you do is find the 4 pins that are used to power the discs in your drive.
Then wire to 3 of these a stereo pair. Usually any order will work I think.
Plug the stereo pair into a line in on your soundcard and voila!
When you spin the hdd you will get a sine that increases in pitch and volume when the disk spins faster.

So the soft is just a 0 crossing counter, and also it use the stereo to tell which direction the motor is travelling, as one of the stereo pair is slightly ahead of the other.

Here is a picture of my one->

Uploaded with ImageShack.us

It has a little DC motor attached to an LP players turntable which has been ground to smaller diameter.
The LED display is volts to the little motor.
I will make a video of it in action to up here

Here is the first one I modded->

Uploaded with ImageShack.us

Cheers folk

Here are some links->
http://synthmaker.co.uk/forum/viewtopic ... +turntable
http://forum.image-line.com/viewtopic.php?t=48769

Hink · Post by **Hink** » Wed May 11, 2011 4:28 pm

wow, that's pretty cool nix

highkoo · Post by **highkoo** » Fri Jul 01, 2011 6:40 pm

Ha!

I made one of these one day!
It is really easy. It took less than ten minutes.

Be careful though. If you spin the platter very very slowly it creates some serious subsonic signals. I have never before seen my speaker cones move quite so much, and make so little noise.

And, seemingly totally unrelated, but immediately following that experiment, the MIDI on my soundcard died, while the audio was fine.. Some mucking around brought it back, but I never found out if it was actually related to the HDD TT.

nix808 · Post by **nix808** » Thu Jul 21, 2011 2:19 am

OK thanks 4 the heads up.
I will be careful if I run the signal to speakers.
The noise the turntable makes isn't routed to the speakers usually, it runs into SynthMaker.
I'll make the vid soon.
It flux by 3% speed, I think the wheels are out.
Need to get all parts turned, and use a motor with less resistance to spinning.
I suspect the servo is accurate enough to create a pro device.

Compyfox · Post by **Compyfox** » Sun Jul 24, 2011 12:14 pm

Well, aparently there is a youtube video over on the ImageLine boards:

It's quite impressive that the motor itself creates some sort of pulse signal that then a software can interpret. This could be a revolution on the DJ market (and sure as hell reduce all the crazy controller stuff needed, aka sales would go back).

If this could be used for more than scratching (like host controlling (jog shuttle), I'd take a closer look. Else, it looks farily simple to create. So if there's a software out, and I'm in the mood modding an old headcrashed HDD, I'll give it a spin.

Er... yeah.

nix808 · Post by **nix808** » Mon Jul 25, 2011 10:49 am

hehe,
If you want the software at any stage, let me know and I'll hook u up.
I have taken a video of it, and will up to u-tube.
I will soon start building the mkIII, it uses spur gears at 144:11 ratio, and the hdd motor is coupled directly to the DC motor. Hopefully this is more accurate, as there is no slippage of belt or wheels.
Cheers

nym · Post by **nym** » Mon Jul 25, 2011 6:00 pm

uh....?!?!
yes i want the software, hook it up please
i've been wanting to use hd platters for rotary encoders/jog wheels for ages now, and this could make it possible.

highkoo · Post by **highkoo** » Mon Jul 25, 2011 7:06 pm

nym wrote:uh....?!?!
yes i want the software, hook it up please
i've been wanting to use hd platters for rotary encoders/jog wheels for ages now, and this could make it possible.

Follow.
Links.
They link to things of relevance.

nix808 · Post by **nix808** » Tue Jul 26, 2011 2:08 am

http://www.sendspace.com/pro/dl/zr0dko
Here is the VSTfx.
Load it up on your audio track in DAW.
There is only functional GUI.
I retain copyright.
It's not perfect, but it's getting there.
By imperfect I mean even without wheel slippage it does not track to the same spot on the disc perfect all the time. It's pretty good though, I think I still build the gears one.
The display use stacks of CPU, but it is the minimum resolution I thought was acceptable. It defaults to off, so hit the unmarked switch to turn on the scrolling waveform.
If u find it interesting I can share the SM .osm w/- u.
Cheers eh
It can be turned into an endless encoder.
PS- This system is called 'Tablist', it's my moniker 4 this project, I want dibs on the name

nym · Post by **nym** » Tue Jul 26, 2011 4:23 pm

It can be turned into an endless encoder.

cheers.

while i am totally interested in the use of your software for a scratching solution, my immediate interest is in an endless encoder. i have loaded your plugin and i am examining it. how would you recommend turning this into an endless encoder?

here is my story:

i am building replacement hardware for the MPC1000 and MPC2500 samplers...
the buttons and rotary encoder of these 2 instruments are very poor.
a HD is a far better rotary encoder than any other rotary encoder you can buy.

my goal: to have the plugin output 2 different midi note signals: one for forwards movement and one for reverse movement of the HD. if a user spins the HD, a midi note on/off is repeated depending on the speed of the movement. in reverse, the other midi note on/off is repeated depending on the speed of the movement. in this way, a rotary encoder is emulated: the faster you spin a rotary encoder, the more rapidly data is sent.

please, please share the osm with me! i have not worked with synthmaker yet but i am OK with C++ and i'm a quick learner...

nix808 · Post by **nix808** » Tue Jul 26, 2011 4:42 pm

SM is very easy to use , since you can code.
Any application within SM would be fine to send data to.
Hmm, I'm not sure about sending it over MIDI though, what device would be controlled?
SM has an inherent limitation as far as MIDI goes, in that max speed you can send data is 100hz.
I have circumvented this with a MAX/msp .exe, so that it goes to 22050 hz.
This speed is the max you will be able to send a number over MIDI.
I'll pm you the .osm now 8D, I'm hoping in the long term it might be a hardware product, I would appreciate consultation b4 sharing it.
Cheers, I hope this can work 4 u
Actually I send you the MAX .exe too, so you have quick triggering of MIDI data
Please feel free to pick my mind on this one, however much shortcomings it has!
edit-at least I think it can be a rotary encoder

highkoo · Post by **highkoo** » Tue Jul 26, 2011 10:06 pm

Cool to see someone refining this idea. Its been around for a while and it seems like no one ever put time in to get it right.

nix808 · Post by **nix808** » Tue Jul 26, 2011 11:16 pm

I'm going to try and get a quote for the gears today.
I have been directed to 2 local suppliers.
Thankfully they are a stock gear.
OK I see now that you want to control the mpcs.
I will think about your problem.
Let me know if the pm came through alright

I mean to find out if this can be done sufficently well yep,
it's quite a cool little function.
I have sourced about 200 hdd motors for $6 each.
I think I'll get 6 to start with.

nym · Post by **nym** » Wed Jul 27, 2011 4:59 am

nix808 wrote:OK I see now that you want to control the mpcs.
I will think about your problem.
Let me know if the pm came through alright

pm came through loud and clear, i began familiarizing myself with synthmaker
i downloaded an osm from a feller on the sm forums who modified your code into an endless encoder w/ ccs and i will probably be working with that at first unless it's outdated.

thank you for your help in this matter!

nix808 · Post by **nix808** » Thu Jul 28, 2011 11:39 pm

You're welcome nym,
If you need more encoders, there's this->
http://www.brushless-motor.wrobots.com/24C1838030.php
Also, I think perchance CD player motors might work, and they are smaller.
Cheers 8D

HDD Turntable controller