Messages

1651

preenfm2 and preenfm3 / Re: preenfm2 Editor (nothing ready yet)

« on: June 24, 2014, 09:16:32 PM »

1. Thanks 
2. Yes, but could be done in the pfm2 firmware directly.

Final question : I'm afraid it won't work with ableton live. Editor <=> preenfm2 communication is 100% NRPN.

Xavier

1652

preenfm2 and preenfm3 / Re: Built a new one :)

« on: June 24, 2014, 09:11:33 PM »

Hi Mike,

Here is a quick picture i just made.
Let me know if that helps.

If you can take picture of both your jack and PCB with the header and a close view of the area around the optocoupler.
A wrong diode direction would also prevent the Midi in to work.

Xavier

1653

preenfm2 and preenfm3 / Re: Patch Randomiser

« on: June 23, 2014, 10:15:50 AM »

The mb6582 has an interesting implementation- you can choose which sections to randomize, like oscs, modulations, filter, seq etc. Would be interesting if a similar approach was adapted to the preen engine, and would be a good solution to the unusable outcome problem.

That sounds like a great idea. Thanks...   

1654

preenfm2 and preenfm3 / Re: Patch Randomiser

« on: June 22, 2014, 08:45:22 PM »

Seems like i'll have to work on that one day.

Could be written internally also.
But it's not obvious.
As 6581punk said,  pure random would lead to 99.9% of unusable sound.

Xavier

1655

preenfm2 and preenfm3 / Re: preenfm2 Editor (nothing ready yet)

« on: June 18, 2014, 09:13:47 PM »

Thanks i'll give a try.

1656

preenfm2 and preenfm3 / Re: operator feedback

« on: June 18, 2014, 09:13:23 PM »

At the end of the compilation you get a memory dump.
The following lines are interesting :
                                                                                     
  [ 3] .data                   PROGBITS       20000000 050000 002a8c 00  WA  0   0  8
  [ 4] .jcr                      PROGBITS        20002a8c 052a8c 000004 00  WA  0   0  4
  [ 5] .bss                    NOBITS             20002a90 062a90 0085fc 00  WA  0   0  4
  [ 6] .ccm                   PROGBITS       10000000 058000 0090e8 00  WA  0   0  4
  [ 7] .ccmnoload      NOBITS             100090e8 0610e8 006074 00  WA  0   0  4

10000000 is CCM (64kb)
20000000 is regular mem (112kb)
After the adress, first value is offset the second one is size.
CCM :
We have 0090e8 + 006074 = 61788 bytes out of 65536.
The descending execution stack starts at the top of this memory, so we can consider it's full.

Standard memory:
002a8c + 000004 + 0085fc = 45196.
So yes there's free RAM here for new waveforms 

Are there any other good sites or books to read about coding in C for music applications such as the PreenFM2? Are there any differences when coding for an ARM vs the ATMega?
...
Also, to remove the DC offset created by operator feedback, would we subtract the mean from the signal?

I don't think there's book for coding music applications in C. There is C/C++ on one side and understand how a synth work on the other one.
Then there are lots of information on the web to link both sides.

To remove DC use a simple HP filter.
You can have a look here :
https://github.com/Ixox/preenFM2/blob/master/src/synth/Voice.cpp#L2952
And line 2967 and 2987.
I filter freq4 to remove DC.

Xavier

1657

preenfm2 and preenfm3 / Re: operator feedback

« on: June 17, 2014, 09:34:49 AM »

The second part here is good :
http://www.musicdsp.org/showone.php?id=160
Replace "PM is better that FM" by "PM is different...." 

"(with PM)... cascaded carrier-modulator pairs and feedback modulation are possible."
I added LP filter for cascaeded operators to get rid of the constant frequency value (pitch shifting).
For feedback we should do the same.

Xavier

1658

preenfm2 and preenfm3 / Re: Midi sequencing Problem

« on: June 16, 2014, 04:17:59 PM »

Thanks Kuzma for your feedback, good to know. 

1659

preenfm2 and preenfm3 / Re: [Sold out] preenfm2 white metal case

« on: June 16, 2014, 03:43:55 PM »

Yes, a new run will start very soon, metal case alone will be available in August.

1660

preenfm2 and preenfm3 / Re: Midi sequencing Problem

« on: June 15, 2014, 11:28:34 PM »

An other idea :

Have you checked the midi channels the octatrack sends to ?
By default the 4 preenfm2 instruments listen to channel 1, 2, 3 and 4.
That can be changed in the menu.
You can change the 1st instrumnet to listen to ALL channel, to see what happens then.

Xavier

1661

preenfm2 and preenfm3 / Re: LEDs when building with the metal case.

« on: June 15, 2014, 11:13:29 PM »

Great, thanks for the nice words 

1662

preenfm2 and preenfm3 / Re: Midi sequencing Problem

« on: June 15, 2014, 11:13:10 PM »

Hello,

What do you trig from the sequencer ? midi note on ?
The numbers shows up when the preenfm2 receive midi note on... So if you send CC for example, you won't hear anything and won't see anything.

Have you checked sending the same sequence to another sound module ?
Or even better to a midi monitor program on your computer ? That would allow you to understand exactly what the octatrack sends.

Let me know what you find,

Xavier

1663

preenfm2 and preenfm3 / Re: LEDs when building with the metal case.

« on: June 15, 2014, 08:57:10 PM »

Hi,

Yes they'll be hidden behind the metal.
You may see them through the knob holes if you screw the knobs enough above the surface control.

The 4 leds do not show any information. They're just nice.
Their only goal is to blink in sync with your external midi clock. They always blink all at the same time.
And a little note on the display blinks at the same time too.

Xavier

1664

preenfm2 and preenfm3 / Re: waveforms

« on: June 14, 2014, 09:51:01 PM »

and yay!! lots of fun.

I like this last line 

1665

preenfm2 and preenfm3 / Re: operator feedback

« on: June 14, 2014, 09:50:10 PM »

Feedback is less usefull when the synth offers you several waveform to chose from. Often use in DX7 to create saw or noise.
In adition it is very easy to implement with phase modulation (DX7) but it's more complicated with real FM (preenfm).
With FM, yhe feedback will change the pitch of the operator... You'll need to add a HP filter to get rid of the constant value.

Feedback should be a variable of the Voice class so that it can remember the value and reinject it the next loop iteration.

Xavier