Linux-audio-user March 2009

linux-audio-user@lists.linuxaudio.org

120 participants
123 discussions

by Pascal Lawrynowicz

Hi, Couple of days ago I saw a thread about learning drums rhythms. Maybe my website can help : www.percunivers.com (click on the uk flag for the english version). Not only about drums, because everything is made under 64Studio (mainly ardour and lilypond). The weak point is about mp3 for the exercices. I have no choice because this is the only format I can use for streaming (via flash, argh!) and the only way to have my mp3 played on any Ipod-like from my students. I'm open for any open solutions... Maybe this can help, hope you send me any feedback. Thanks, PL

16 years, 10 months

[LAU] how to record Gramophone?

by Grammostola Rosea

Hi, My dads want to records some old gramophone records. How can he do it? Ardour/ Audacity? \r

16 years, 10 months

[LAU] Easy sound morphing?

by shane richards

I've been trying to do some sound morphs between two different hits of a snare drum, one rimshot and the other a plain hit. I tried using SMSTools, and even some windows programs under wine, but the results always seem to sound more like hitting a bucket full of water than a combination of the two drums. I tried csdrummer, but only get a horrible scratchy noise from it. I looked at Loris...the python-based example that comes with it seems horrifically complicated. Maybe someone with a knowledge of Csound/Loris could be kind enough to help with a simple script? Or a step-by-step how to achieve this with Cecilia? Are there any other programs I could try?

16 years, 10 months

[LAU] Running Status v.s "Ordinary" Status and MIDI merging

by Crypto

Hi, I am stuck in a problem with MIDI merging. I am currently using two external MIDI devices that connect to my notebook via an external USB MIDI adaptor (a nice Edirol UM2). One of these devices transmits data in running status, which means it omits the status byte of NOTE ON messages if many NOTE ON messages are transmitted and there is no change of the channel. The second device transmits data in the ordinary uncompressed mode and never leaves out the status byte. Now I need to route these external MIDI devices to a MIDI application. The devices show up in my notebook as physical ports UM2-1 and UM2-2 and what I do is to simply connect these ports to the IN port of the MIDI application. And now there is a problem: as I have connected the two devices to the IN port the application (or the driver of the MIDI port) has to do MIDI merging. But something is wrong with the merging, if the running status device's data bytes have to be merged with the second device's data stream. The application detects that there is the status byte missing in the complete data stream that it is receiving and it does not "resync" even if the running state device transmits a status byte because the channel has changed. So the application indicates an error message stating there is a missing status byte and that it only got data bytes. 1.) Which part is actually responsible for the MIDI merging of two or more output devices into one input device? Is it the driver of the port or is it the application, that is in the end receiving the MIDI data stream? 2.) Is it illegal to connect two output devices to one input port? 3.) If I should need some kind of virtual MIDI multiplexing/demultiplexing driver: which one should I chose? I have debian and would like to install from repository. Thanks for any hint and kind regards, Crypto.

16 years, 10 months

[LAU] [ANN] jack enabled flash...

by torbenh＠gmx.de

hi... i wrote an audio output driver for flashplayer, based on lennart poetterings pulse driver. git clone git://repo.or.cz/libflashsupport-jack.git -- torben Hohn

16 years, 10 months

[LAU] snd-virmidi not working

by Crypto

Hi, I understand that the module snd-virmidi can be loaded via modprobe from the command line. BUT: I cannot get it to work. The module does not pass any data transferred to it. What am i doing wrong? I simply connected one MIDI output of things like the vkeybd to the virtual MIDI port and then connected kmidimon to the virtual port to see if something is happening. But nothing. Any helpful hints on this? kernel is 2.6.29-0.slh.1-sidux-686. MIDI is working fine otherwise. Regards, Crypto.

16 years, 10 months

[LAU] jdelay - measured latency of a usb interface

by hollunder＠gmx.at

Hi everyone. I was kind of curious about the real latency of my system and did a series of tests using jdelay (http://www.kokkinizita.net/linuxaudio/). I share my results so others can see what to expect from such a usb audio device and also because.. ! Important ! I ran in a number of oddities that I can't explain myself. This could mean that my results here are totally useless, so please don't take them for real until someone can hopefully clarify those matters. General Information: ------------------- Audio Interface: Edirol UA-25 http://www.rolandus.com/products/productdetails.aspx?ObjectId=704 http://alsa.opensrc.org/index.php/Edirol_UA-25 It can work in 44.1, 48kHz duplex and 96kHz either record or playback, so I couldn't (and wouldn't have anyway) tested 44.1 and 48kHz. There are Periods/Buffer from 2 to 42 possible, most common is I believe 2 and 3 Periods/Buffer, I only tested these. My pc is rather old, mainboard is a via km400 or km400a if that helps anything. On the software side there is Arch Linux with it's latest stock kernel, 2.6.28.8, jack 0.116.2 and qjackctl 0.3.4 (the patchbay made this a lot easier). Measurement Results: ------------------- SR 44100 ----- Frames Periods F*P/SR Measured 64 2 2.9 8.2 128 2 5.8 11.1 256 2 11.6 15.9 512 2 23.2 28.5 1024 2 46.4 52.7 2048 2 92.9 102.1 4096 2 185.8 187.1 64 3 4.4 9.7 128 3 8.7 14.0 256 3 17.4 22.7 512 3 34.8 30.1 1024 3 69.7 65.0 2048 3 139.3 138.6 4096 3 278.6 279.9 SR 48000 ----- Frames Periods F*P/SR Measured 64 2 2.7 7.9 128 2 5.3 10.5 256 2 10.7 15.9 512 2 21.3 26.5 1024 2 42.7 48.9 2048 2 85.3 94.5 4096 2 170.7 171.9 64 3 4 9.2 128 3 8 13.2 256 3 16 21.2 512 3 32 27.2 1024 3 64 60.2 2048 3 128 127.2 4096 3 256 257.2 Questions to the wise guys: -------------------------- 1) As probably everyone has noticed, with 3 periods/buffer and frames/period of 512, 1024 and 2048 the measured latency is smaller than the calculated latency. I don't see how this can be possible since, as far as I understand it, the measured latency should be the calculated + some. 2) When doing those measurements I noticed that with 44100 the Frames reported by jdelay always ended in .732 Frames and with 48000 always ended in .761 Frames. I found out that I can change that value by changing the sensitivity of the input or the amplification of the output. In the case the variance is below one frame, but I find it very strange that it's always the same at a given amplification/sensitivity. 3) Is it normal that the difference between calculated and measured latency varies so much? Shouldn't it just always be the same? 4) Should these results be similar with any usb interface? What does have most influence on such results? I hope this can be of use after the remaining questions have been answered. Best regards, Philipp

16 years, 10 months

[LAU] moving firewire interface to other interrupt

by Atte André Jensen

Hi It seems at least part of my problem with my edirol fa-66 firewire card is due to the fact that it shares interrupt with the graphic card :-( atte@vestbjerg:~$ lspci -v <snip> 00:02.0 VGA compatible controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controll er (rev 03) (prog-if 00 [VGA controller]) Subsystem: Toshiba America Info Systems Unknown device ff50 Flags: bus master, fast devsel, latency 0, IRQ 17 Memory at f0000000 (64-bit, non-prefetchable) [size=1M] Memory at d0000000 (64-bit, prefetchable) [size=256M] I/O ports at 1800 [size=8] Capabilities: <access denied> <snip> 00:1a.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #4 (rev 03) (prog-if 00 [UHCI]) Subsystem: Toshiba America Info Systems Unknown device ff50 Flags: bus master, medium devsel, latency 0, IRQ 17 I/O ports at 1820 [size=32] <snip> 0a:01.0 FireWire (IEEE 1394): Ricoh Co Ltd R5C832 IEEE 1394 Controller (rev 05) (prog-if 10 [OHCI]) Subsystem: Toshiba America Info Systems Unknown device ff50 Flags: bus master, medium devsel, latency 32, IRQ 17 Memory at f0400000 (32-bit, non-prefetchable) [size=2K] Capabilities: <access denied> <snip> I looked in the bios, but it seems interrupts can't be moved around (it's a toshiba laptop). Is there anyway to move the interrups by software? Anything else that could be done? Or should I simply admit I wasted my money and use the fa-66 as paper weight? -- Atte http://atte.dk http://modlys.dk

16 years, 10 months

[LAU] playback glitches with the edirol ua-101

by Miles Egan

I have this USB audio interface working with my Ubuntu 9.04 system, but I get very frequent clicks and pops, whether I run it via jack or directly through ALSA. I don't get these pops with either a Native Instruments Audio Kontrol 1 or a Novation Xiosynth. Could this be related to the playback sync issue mentioned here? http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h… Does anybody have this interface working without these glitches? -- miles http://kuniklo.bandcamp.com

16 years, 10 months

[LAU] use your pc as an music player (and safe energy)

by Grammostola Rosea

Hi, Music is digitalized now and so I use more and more my pc for listening to music. I guess this are just modern times.... But this are also the times of a planet what get destroyed and less important money just disappears... So I want to save as much energy as possible without buying another pc. Is there a way to handle this? What are the tricks or are there 'green' distro's? Thanks in advance, \r

16 years, 10 months

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Linux-audio-user March 2009