I have an external USB hub with its own power supply. It introduces a hum when I have its PS connected.
David W. Jones
gnome(a)hawaii.rr.com
authenticity, honesty, community
http://dancingtreefrog.com
On Mar 30, 2015 1:00 PM, Len Ovens <len(a)ovenwerks.net> wrote:
>
> On Mon, 30 Mar 2015, Fons Adriaensen wrote:
>
> > Some week ago I had some spare time and decided to have a look at
> > it. Connected the USB to my Linux workstation and connected some
> > headphones to the mixer. Result: with all faders down and just
> > the HP volume turned up there was a high level 50/100 Hz in the
> > headphones. Removing the USB connection was enough to stop it.
>
> Good to know. The last mixer I bought I went through channel by channel
> and each control looking odd things like that. I would have thought there
> should be no analog Audio anywhere near the USB.
>
> --
> Len Ovens
> www.ovenwerks.net
>
> _______________________________________________
> Linux-audio-user mailing list
> Linux-audio-user(a)lists.linuxaudio.org
> http://lists.linuxaudio.org/listinfo/linux-audio-user
On Wed, April 1, 2015 2:03 am, Patrick Shirkey wrote:
> So you are saying that Behringer manufactured and released
> an entire range without testing *any* of them before they
> went out the door for ground loop issues at the board/design level?
Something much more limited and specific: I am saying that the
description provided by Fons of the behavior of that specific model of low
cost mixer is consistent with a "pin 1 problem" design flaw, although that
is a bit of a misnomer with a USB connector. "Pin 1 problem" is much
easier to say than "reference conductor common mode impedance noise
coupling" though. Possibly only affecting the headphone output, Fons
never mentioned whether he also checked the main or monitor outputs.
> Seem pretty unlikely even for cheap low end manufacturing from China.
Where the unit was manufactured has no bearing on where it was designed,
and there are examples of pin 1 problems even in expensive equipment.
With proper PCB layout noise from the computer chassis should not be a
problem. The problem and how to avoid it were popularized in the June
1995 Journal of the Audio Engineering Society, they devoted an entire
issue to grounding and shielding problems, and Jensen and Rane have also
spread the word through several white papers and tutorials. Many seminars
have been taught by Bill Whitlock of Jensen and Jim Brown of Audio Systems
Group consulting among others. This is not something esoteric.
> More likely this one just slipped through the (random) QC process
As Fons pointed out, the typical design style for that class of equipment
has all connectors soldered to a single PCB, and most of the assembly of
the PCB is performed by automated equipment. The balance of likelihood
between an assembly flaw that allows the equipment to work, but not work
fully properly, and a design flaw comes down on the side of design flaw
for this particular behavior. The solution is relatively straight
forward, but you have to fight against the easy way of doing things using
most PCB layout software, so it is commonly not done correctly.
> From his description it sounded like the device was working
> pretty good with Linux in every other way. Just a bit of
> hum at the hardware level.
Indeed, the improved standardization of USB interfaces has been very good
for linux audio. It would be interesting to see if the problem affected
every unit or was a manufacturing flaw as you speculated, and whether the
problem affects all the outputs or only the headphone amp.
Fons, did you happen to get the specific model number of that mixer?
--
Chris Caudle
Hi,
I bought samples from Dubsounds in SF2 format, and looping is wrong
when rendering with fluidsynth. I'm wondering how to check whether this
is caused by buggy files or a bug in fluidsynth.
The symptoms:
-- in fluidsynth (command line, qsynth, Calf plugin, or Carla), I can
hear that looping is wrong -- there is obviously a gap
-- in swami, the start loop point seems ok, but the end loop points is
beyond the end of sample. When loading the soundfont, it spits a bunch
of "libInstPatch-WARNING **: Invalid loop for sample" on the console
-- in polyphone, it loads and plays ok. Loop points are perfect.
Is there some extension or advanced feature that polyphone supports but
not fluidsynth nor swami? How may I know who is the culprit?
Here is the output of sf2dump: http://pastebin.com/CthdwrQf
Thank you,
-Alexandre.
Hi,
It seems to me that the Behringer folks have done a Linux version of
all their editors for their entire range of digital mixers and also
Android versions of the GUIs. I'm pretty impressed!
That's a complete different way of doing it compared to for example
Mackie and Line6, who avoid to even take the word Linux in the mouth
officially - that's the way I feel it anyway. Well, Line6 discovered a
while back that something called Android exists and provided Android
GUIs for some of their products.
If I understand everything right the X32 can be connected to a Linux PC
and then the channels are discovered by Alsa and can be used by Jack.
Have anyone here tested the X Air series?
Jostein
we are searching for a new audio interface for a project studio and
interested in the experiences others have had
requirements are:
* 8 (or more) channels simultaneous recording to computer
* at least 4 preamps for mic level inputs
* USB2 preferable to Fireware, but..
* 100% linux compatible, ideally with a stock kernel
* under $500 USD if possible
less important is real-time monitoring functionality - this will mostly
be used for bands playing live
there are several new inexpensive USB2.0 interfaces that would
apparently fit the bill if supported under linux but it is not clear if
they are, seems like in contrast to FW most are not
anybody have any recommendations?
Yoshimi continues to grow, and today we have V 1.3.4 out there.
There are times for big things, and times for great things, but today was the
time for (lots of) small things :)
Less about features, more about user 'comfort'.
Enjoy.
--
Will J Godfrey
http://www.musically.me.uk
Say you have a poem and I have a tune.
Exchange them and we can both have a poem, a tune, and a song.
Hi Len,
I didn't keep the Message-ID of the original thread.
On Sun, 29 Mar 2015 23:01:19 -0700 (PDT), Len Ovens wrote:
>Tracktion is not good enough to switch for me. The jack
>implementation is a bit odd. The one interesting thing it did do was
>to recognise my Yamaha DD11 channel 16 is really drums and map them to
>channel 10 when I recorded them.
Sequencers should provide a matrix to assign each drum voice to an
individual different note on any wanted MIDI channel. Some sequencers
do provide such a matrix.
I own a DD-11 too and it's owner's guide mentions that it provides 3
kicks, they are assigned to C1 (36), G#1 (44) and A1 (45). IOW 2 of the
3 bass drums are assigned to note numbers, that don't match with GM, so
just mapping to MIDI channel 10 not always does the trick. My RX21
provides a kick on A1 (45) only and my TG33 provides the bass drum on
C1 (36), G#1 (44) and A1 (45). G#1 (44) and A1 (45) on GM devices are
for Hi Hat and Tom, that is the way as my Roland MT-32 and my Alesis D4
factory drum kits provide it.
GM might be useful for some needs but for studio work a matrix is
needed.
IMO a drum kit by default should match as close as possible to GM, but
it's common practise to use drum samples from different devices, so a
matrix is needed anyway.
Regards,
Ralf
And finally, for the wrap of the pre-LAC2015@JGU-Mainz [1] release
party, no other than the 'crown jewel' of the whole Qstuff* bunch ;)
Qtractor 0.6.6 (lazy tachyon beta) is out!
Release highlights:
* LV2 and VST plugins GUI position persistence (NEW)
* MIDI clip editor record/overdub note rendering (FIX)
* VST plugin recursive discovery/search path (NEW)
* VST-shell sub-plugins support (FIX)
* also some old and new lurking bugs squashed.
Qtractor [2] is an audio/MIDI multi-track sequencer application written
in C++ with the Qt4 framework. Target platform is Linux, where the Jack
Audio Connection Kit (JACK [3]) for audio and the Advanced Linux Sound
Architecture (ALSA [4]) for MIDI are the main infrastructures to evolve
as a fairly-featured Linux desktop audio workstation GUI, specially
dedicated to the personal home-studio.
Website:
http://qtractor.sourceforge.net
Project page:
http://sourceforge.net/projects/qtractor
Downloads:
http://sourceforge.net/projects/qtractor/files
- source tarball:
http://download.sourceforge.net/qtractor/qtractor-0.6.6.tar.gz
- source package (openSUSE 13.2):
http://download.sourceforge.net/qtractor/qtractor-0.6.6-16.rncbc.suse132.sr…
- binary packages (openSUSE 13.2):
http://download.sourceforge.net/qtractor/qtractor-0.6.6-16.rncbc.suse132.i5…http://download.sourceforge.net/qtractor/qtractor-0.6.6-16.rncbc.suse132.x8…
- quick start guide & user manual (see also: the wiki):
http://download.sourceforge.net/qtractor/qtractor-0.5.x-user-manual.pdf
- wiki (help really wanted!):
http://sourceforge.net/p/qtractor/wiki/
Weblog (upstream support):
http://www.rncbc.org
License:
Qtractor is free, open-source software, distributed under the terms
of the GNU General Public License (GPL [5]) version 2 or later.
Change-log:
- MIDI clip record/reopen to/from SMF format 0 has been fixed.
- LV2 and VST plugins GUI editor widget position is preserved across
hide/show cycles.
- Added application description as freedesktop.org's AppData [6].
- Added a "Don't ask this again" prompt option to zip/archive extrated
directory removal/replace warning messages.
- MIDI clip editor (aka. piano-roll) gets lingering notes properly shown
while on record/overdubbing.
- Current highlighted client/port connections are now drawn with thicker
connector lines.
- Fixing segfaults due to QClipboard::mimeData() returning an invalid
null pointer while on Qt5 and Weston.
- Return of an old hack/fix for some native VST plugins with GUI editor,
on whether to skip the explicit shared library unloading on close and
thus avoid some mysterious crashes on session and/or application exit.
- Force reset of plugin selection list when any of the plugin search
paths change (in View/Options.../Plugins/Paths).
- Recursive VST plugin search is now in effect for inventory and
discovery on path sub-directories (VST only).
- Non-dummy scannig for regular VST, non-shell plugins, were doomed to
infinite-loop freezes on discovery, now fixed.
References:
[1] LAC2015@JGU-Mainz - Linux Audio Conference 2015
The Open Source Music and Sound Conference
April 9-12 @ Johannes Gutenberg University (JGU) Mainz, Germany
http://lac.linuxaudio.org/2015/
[2] Qtractor - An audio/MIDI multi-track sequencer
http://qtractor.sourceforge.net
[3] JACK Audio Connection Kit
http://jackaudio.org
[4] ALSA, Advanced Linux Sound Architecture
http://www.alsa-project.org/
[5] GPL - GNU General Public License
http://www.gnu.org/copyleft/gpl.html
[6] AppData Specification
http://people.freedesktop.org/~hughsient/appdata/
See also:
http://www.rncbc.org/drupal/node/879
Enjoy && keep the fun.
--
rncbc aka. Rui Nuno Capela
On Sun, 29 Mar 2015, Ben Bell wrote:
>> starts at boot and stop at shutdown) Are you using jackd or
>> jackdbus? If you are using jackdbus, you may wish to try chmod -x
> Actually I just did the opposite and disabled jackdbus, because jackd I
> understand (I think ;).
There is no documentation for jack_control and if I recall jack_control -h
or --help do not work either but jack_control on it's own does. I think it
is just a python script so looking through the file with an editor or
pager would work too. I like jackdbus because the application that starts
it is not the only one that can manipulate things in it. I find it very
flexable. However using what you are used to is a great idea. You don't
need to learn two new things at the same time.
>> I am sure if you powered the d1010 down while the system was running
>> you would have similar problems or worse. Don't do that. I think if
> Again, that's a fair point and it's partly only because of the problems
> I'm having that I find myself doing it. With the Delta 1010 the external
> rack boxes could be powered down but of course the cards stayed powered.
I was not aware of that as the delta 66 box does not have a power switch
on the breakout box.
> I do still think that it ought to be possible to power the Focusrite down
> and get an error and a jack shutdown rather than hanging, but if not I'll
Actually, it is quite reasonable to expect an external audio IF should be
able to be connected or disconnected on the fly... but I think last time I
tried that with a USB interface (ALSA driver) things were difficult as
well. I was going to ask if you had tried the ALSA FW stack.
> On the click side of things, I've found a firewire debug setting and turned
> it up and can now see that the clicks correspond perfectly to kernel
> messages like this:
I do not know enough about fw to say. I don't recall now if you are still
using a desktop (as with the d1010s). If so I would try moving the FW
interface to different slots to see if this helps. Prioritizing the irq of
course helps too, but I am assuming you have already done so.
trying 32/3 instead 64/2 or any */3. This is just generally a good idea
with any "networked" audio IF such as FW, USB or AoIP.
--
Len Ovens
www.ovenwerks.net
Just noticed what appears to be a difference between Yoshi and Zyn when
using otherwise identical settings. I have an improv thing I do that
involves holding a low D (as a drone), sustain pedal down, the stock
Cathedral 1 reverb, using the Flanged Pad 1 instrument. Then I play a
bunch of descending scales, just letting the notes accumulate.
On Zyn, no matter how many notes I play, the low drone remains; if I
lift the sustain, the lower note is still playing.
On Yoshi, after a certain number of notes, the low drone stops; if I
lift the sustain, the lower not is NOT playing.
I put the Yoshi and Zyn screens side-by-side and it looks like the
settings are the same in each.
What's up with that?
--
David W. Jones
gnome(a)hawaii.rr.com
authenticity, honesty, community
http://dancingtreefrog.com
