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7448 discussions

[ot] rme fireface: weird balanced output measurements

by Jörn Nettingsmeier

hi everyone! yesterday, i visited my friends' new studio, to help them shake out some bugs in the patch and fix a monitor problem. there i came across a really weird issue with the line outputs on two rme fireface 800s: we put a test tone out in logic (yeah, they run a mac shop), and i went to measure the outputs. in addition to really high fluctuations from one output to the next (with identical digital input signals), i measured huge differences in voltage on the hot and cold side, such as hot to ground: 2.00 V cold to ground: 1.82 V despite the fluctuations across several channels, this trend was pretty constant. so i figured, maybe this box has a problem with its negative voltage rail. they had another ff 800 in there, which we measured for comparison. same issue. i figured, maybe apple wrote an oscillator with a dc offset, so we applied a known-good test tone .wav file. same result. is my thinking flawed, or are rme really delivering such crappy output stages on such a pricey box? my multimeter is not a calibrated one, but it's in the 100+€ range, and i used AC true rms measurement mode. i understand my meter has a very high input impedance, and that's what line level connections should have, right? operating more or less open-loop, without significant currents flowing. or should i use a shunt resistor and measure across that? if so, what value is recommended? thanks for any insights, best, jörn

12 years, 7 months

DrMr: a new lv2 sampler/drum machine plugin

by Nick Lanham

Hello all, I've written a new sampler/drum machine lv2 plugin called DrMr. You can find it here: https://github.com/nicklan/drmr It's main reason to exist is to give a way for lv2 hosts to have a built in drum synth that can save its entire state (i.e. no need to go out to external tools and no need to save extra state). DrMr currently supports the following: - Control via midi - Scan for and load hydrogen drum kits - Multi-layer hydrogen kits (will pick layer based on that sample's set gain) - Kit is set via an LV2 control - LV2 controls for gain on each sample - LV2 controls for pan on each sample - GTK ui that can select a kit and control gain/pan on each sample There's more info in the README.md which you can see if you click the above link. There are a couple of screenshots on the github wiki page. I hope people find it useful, and as it's rather new code, bug reports are of course very welcome. Cheers, Nick

12 years, 7 months

Re: [LAD] DrMr: a new lv2 sampler/drum machine plugin

by Alexandre Prokoudine

On Tue, Feb 14, 2012 at 5:49 PM, Nick Lanham wrote: > Firstly, yes, at some point I would like to have kit editing/creation > available from the GUI. This is non-trivial however, and a bit down the > road. > > To your second point, I agree that it's non-optimal to have to fire up > hydrogen to make minor changes to kits and the like. However, I still think > DrMr improves the situation, as it sits nicely in your host, saves all your > parameters, and doesn't require any external routing. Of course if you're > fine with setting up all the external routing and kit loading etc, you > should just avoid DrMr all together, hydrogen is more fully featured and > almost certainly more stable anyway, but the whole point of me writing DrMr > was that I got sick of having to set up both my host and hydrogen for every > track i wanted to open. Nooooooo, I actually quite like the idea of being able to JFD drums programming directly in a DAW :) The UI could do with quite a bit of love (it's really OK for an initial release), but DrMr is already a huge win for me. > But yes, kit customization is in the pipeline, although behind getting the > core solid and stable. What are the top priorities for you right now? Alexandre Prokoudine http://libregraphicsworld.org

12 years, 7 months

ladspa commandline host?

by Kaspar Bumke

Hi all, I have been running SooperLooper in headless mode on netbook. I don't have X installed on it and just control SooperLooper (SL) via MIDI and OSC. Occasionally I get some clicks which I hadn't experienced when running it with GUI on my laptop. I have tried playing with the SL setting but can't really avoid this happening. I think it may have something to do with the combination of low spec processor and crappy audio card (I had to compiled linux-rt to get it to work reasonably at all). So I wanted to run it through a declipper/noise gate, until I get a better machine or audio card. I know there is a LADSPA one available but all the LADSPA hosts seem to have a GUI. Is there a LADSPA host that doesn't require running X? Regards, Kaspar

12 years, 7 months

LADSPA: Calf Reverb : connect_port strange bug?

by Harry van Haaren

Hey all, I'm currently trying to fix the reverb in Luppp and I'm running into a rather strange bug: I have an array of floats that is used to set the plugins parameters: its called controlBuffer. The following code connects the ports to the addresses of the float buffer. The crazy thing is: The print outs before & after the connect ports are different! I don't understand how this is possible, but perhaps I'm missing something LADSPA. cout << "Decay: " << controlBuffer[4] << " Wet: " << controlBuffer[8] << " Dry: " << controlBuffer[9] << " preDelay: " << controlBuffer[10] << " highDamp " << controlBuffer[5] << endl; descriptor -> connect_port ( pluginHandle , 0 , buffer ); descriptor -> connect_port ( pluginHandle , 1 , buffer ); descriptor -> connect_port ( pluginHandle , 2 , &outputBuffer[0] ); descriptor -> connect_port ( pluginHandle , 3 , &outputBufferR[0] ); descriptor -> connect_port ( pluginHandle , 4, &controlBuffer[4] ); descriptor -> connect_port ( pluginHandle , 5, &controlBuffer[5] ); descriptor -> connect_port ( pluginHandle , 6, &controlBuffer[6] ); descriptor -> connect_port ( pluginHandle , 7, &controlBuffer[7] ); descriptor -> connect_port ( pluginHandle , 8, &controlBuffer[8] ); descriptor -> connect_port ( pluginHandle , 9, &controlBuffer[9] ); descriptor -> connect_port ( pluginHandle ,10, &controlBuffer[10] ); descriptor -> connect_port ( pluginHandle ,11, &controlBuffer[11] ); descriptor -> connect_port ( pluginHandle ,12, &controlBuffer[12] ); cout << "Decay: " << controlBuffer[4] << " Wet: " << controlBuffer[8] << " Dry: " << controlBuffer[9] << " preDelay: " << controlBuffer[10] << " highDamp " << controlBuffer[5] << endl; Example Output: Decay: 4.7685 Wet: 0.70709 Dry: 0.696707 preDelay: 50 highDamp 0 Decay: 1.5 Wet: 0.25 Dry: 1 preDelay: 0 highDamp 5000 The problem is that the reverb plugin doesn't react to my input parameters, but just processes based on the 1.5, 0.25 wet, preDelay 0, and highDamp 5000 *all* the time, and there's nothing I can do about it. Am I doing something fundamentally wrong? I've tried connecting the ports every process(), once, and then leave them. I've hard coded values, it seems to make no difference. These are the two relevant sources: https://github.com/harryhaaren/Luppp/blob/master/src/ladspahost.hpp https://github.com/harryhaaren/Luppp/blob/master/src/ladspahost.cpp Help appreciated! -Harry

12 years, 7 months

It's official I'm selling the real Ardour Tablet! - "check this out"

by Ronald Stewart

It's official I'm selling the real Ardour Tablet With so many discussions about Ardour and real audio apps running on a Tablet, I decided to offer for sale the original Trinity DAW. Funds are going straight to help moms dementia treatment. You can purchase on ebay or at Indiegogo by making the 1000.00 contribution. Just send me an email where to send the merchandise. ronaldjstewart(a)gmail.com Shipping Worldwide Rock on Linux Pro Audio! and thank again to everyone! Ronald Stewart Indiegogo donation page: http://www.indiegogo.com/Cure-My-Moms-Dementia-Today?a=398903 Ebay page: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=250994835490

12 years, 7 months

Version 0.5.2 of The Newtonator available

by Michael Bechard

Fixed in this version: - Compilation bug due to missing gdkconfig.h file The Newtonator is an LV2 soft synth that uses a unique algorithm based on simple ideas of velocity and acceleration to produce some unpredictable sounds. More documentation can be found on the project website at http://newtonator.sf.net/. Thanks, Michael Bechard

12 years, 7 months

fltk woes

by Malte Steiner

Hi, try to brush up a bit Minicomputer software synthesizer which is in a bet shape. I have all sorts of redraw problems with FLTK, seems it started with FLTK 1.3, does anyone experienced similar things and has some tips to share? Google gave nothing, seems I am the only one. Cheers, Malte -- ---- media art + development http://www.block4.com

12 years, 8 months

64 bit tempo-based time stamp

by David Robillard

Hi all, seeking opinions: I have to choose a way to represent beat-based tempo time in 64 bits. Uses are many, but the main one is event time stamps for plugins. Requirements: * No odd data sizes (for performance / programmer ease) * High precision (ideally close to sample accurate for most tempos) * Fits in the same space as two uint32_t's Questions: * Is "bar" needed? * Use floating point? Rounding errors an issue? Options: /* A (moderate range, ultra precise) */ struct { uint16_t bar; uint16_t beat; uint32_t tick; }; /* B (high range, moderate precision) */ struct { uint32_t bar; uint16_t beat; uint16_t tick; }; /* C (high range, good precision?) */ struct { uint32_t bar float beat; }; /* D (high range/precision, but no bar) */ double beat; I havn't run the math on precision yet, but I am leaning towards C. I actually hadn't considered mixing int and float before writing this email, but it seems the best trade-off, and working with float is certainly more pleasant than fixed point. Thoughts? -dr

12 years, 8 months

help with RtMidi and gtkmm

by alessandro filippo

Hi, I'm learning to write simple audio/midi applications in C++ with RtMidi and gtkmm libraries (version 2.4). This is the application I'm working on: http://www.eclepticbox.altervista.org/index.php/download/finish/2-audio-mid… I got some issues with RtMidi IN (Callback). I followed the RtMidi tutorial and the VMPK example (however this is written with Qt), but the problem is that the GUI freezes when I send some MIDI data and it doesn't refresh the widgets values. Midi Out works properly. I think the problem is in the Midi Callback and in the event/signal managing. I tried some function in order to refresh the gui but they didn't work. This is the smallest extract of code that has the issue (only a spinbutton sending / receiving MIDI Program Change): http://www.eclepticbox.altervista.org/index.php/download/finish/2-audio-mid… The sources are in the src folder, see: sawlidsyngui.cpp sawlidsyngui.h Any help is appreciated.... Thanks ... Alessandro

12 years, 8 months

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Linux-audio-dev