Is there such a thing as a "silence signal" in Jack? In the real world obviously not, silence is the absence of sound pressure, but in Jack shouldn't it be possible to fill the channel with 48 kHz (or whatever) of zeroes? And more importantly, does anyone have an easy way to do this??? (Or is it already being done?) I am hearing some faint things in my output that I cannot explain, and a 'silence generator' (if the concept in fact makes sense) would help me figure this out.
--
Jonathan E. Brickman
Ponderworthy Music | jeb(a)ponderworthy.com<mailto:jeb@ponderworthy.com> | (785)233-9977 | http://ponderworthy.com
On Sat, 19 Apr 2014, Jonathan E Brickman wrote:
> Thanks! Do you know of any good such devices which are not very pricey? I
> found a few out there after reading your post, but they seemed all to be in
> the high-port-count and higher-cost ranges.
Cheapest Audio plus midi has got to be the old ens1370 based cards... free
if you can find it. Best 16 bit sound for the price. If you don't have a
pci slot, then the next price range is going to be USB devices... because
most new systems don't have a FW plug, so an adaptor is required. Also,
USB covers more people's systems so scale brings prices lower too. USB
midi ports can be had for less than $30. And of course there are lots of
USB audio solutions out there including built right into the mic stuff,
again under $100. USB audio is much more picky about system tuning for low
latency.
Assuming you already have a FW port, it is a better solution than USB, but
even a 2+2+midi FW unit will cost more than the USB 2+2+midi unit. The
Focusrite line starts with the pro 14 at $260. They call it 8in and 6 out,
but I only see 6 physical inputs (and two of those are s/pdif i/o so only
4 i/o for analog) at $260... yet they sell the 2i2 for usb for $150 or so.
Presonus is the same, their "Firestudio mobile" is similar features and
price to the pro 14 and the price matches too. (just note that it seems to
need breakout cables to get at all the ports... including MIDI) Their
audiobox USB (2+2+midi) can be had for $140.
So, yes FW costs more, but works better/easier. In the end you have to
decide how important moneywise these things are to you. The presonus USB
has been very good and stable... except in USB3 ports on Intel USB3 ports
which are... broken at least for low latency audio (Intel agrees).
--
Len Ovens
www.ovenwerks.net
I realized there was a possibly significant gap in my knowledge of hardware, so I searched, and found that there have been a few Firewire devices with both audio and MIDI. The questions I have are (a) are any of them known to work well with current Linux, and (b) how is the MIDI supported on the backend, is it ALSA?
J.E.B.
Hi,
I recently started using ALSA Jack plug-in bridge and have this issue: My
laptop's sound card has 4 outputs: 1->L, 2->R, 3->Unused?, and 4->"woofer".
When any of the ALSA programs I use (flash player, for example) connect to
Jack, they expose 2 outputs and auto connect to the sound card's 1st and
2nd output. I would like them to auto connect so that the 4th output (the
woofer) is also used. right now, every time I hit play on grooveshark, for
example, I have to go to patchage an make connections from output 1 and 2
in alsa bridge client to 4th output in the sound card.
Is there any way to make this automatic? perhaps by marking outputs 1, 2
and 4 as "default" or "autoconnect"? Maybe there is a hook that detects new
clients and I can write a script that connects alsa clients the way I want?
Now that I think about it, this should not apply only to alsa bridge client
but any jack client!
Regards,
Rafael.
--
Rafael Vega
email.rafa(a)gmail.com
Hi there.
The ingen patches in this page are no longer available:
http://objectivewave.wordpress.com/ams-lv2/
I'd like to try them.
Can someone re-upload them please?
Thanks!
PS: UbuntuOne will go offline and stop working very soon
On Wed, 16 Apr 2014, david wrote:
> On 04/16/2014 03:17 AM, Len Ovens wrote:
>> I was talking about through air. I can only play as fast as I can hear
>> and at thirty feet or so from the sound source, my instrument sounds
>> delayed from the rest of the band because I hear their sound that much
>> later and play my part that much later. I don't normally play at that
>> distance, but ten feet is pretty standard.
>
> You're a few orders of magnitude better than me! I don't think I'd notice
> that much difference.
I used to play and try to adjust sound while practicing, so I had 50 feet
or so of cable. By the time I got to the sound board it was getting hard
to play.
> I use headphone monitor.
I find monitoring with headphones when playing bass is hard. I use a small
amp tilted back about 10 feet ahead of me... so 13-14 feet to my ear I
guess. Bass needs some space to work. My amp just gives me enough for me
and the board can add whatever they want to the mains. I go a bit heavy on
the high end for my monitor and the mains can roll that off for house
sound.
> That's my understanding, too. Things like staying away from USB mice and
> keyboards, making sure the USB audio is the only device on that bus, yah?
On that irq... same for pci(e) really even prioritizing shared irqs, lone
irqs are still best.
>> However, it looks like I can still get lots of MB with PCI slots in
>> them. I will probaly do that. Hopefully with three PCI slots I can get
>> one that is irq clean.
>
> My desktop has 2 PCIe slots; the other 4 are PCI. It also has 4 USB ports +
> 2 more USB connector points on the mobo, 4 SATA connectors, an EIDE
> connector, a floppy connector, plus the built-in audio and video and
> Ethernet. I haven't checked to see what's sharing interrupts and what isn't.
> I wouldn't be surprised if there aren't a bunch of shared interrupts!
cat /proc/interrupts will tell you that quick enough. For some reason a
lot of MB share irq16 with 3 or 4 things... worse one of those tings is
often one of the PCI(e) slots. No need really as most modern MB have
access to 48 plus irqs. My old board has 24 but 2-7 are unused (for
hysterical reasons?) and 10 and 13 seem to be skipped too. I think 20 goes
to my internal audio which I have turned off (AC97) so it doesn't show.
I have noticed that on any of the MB I have checked or seen irq maps for
that the internal audio always has it's own irq and quite often it is the
highest one which in most systems these days has the most priority. I
found this out because I had the card I was using for midi in the higher
of the two slots and my audio below. I had trouble with xruns on the
audio, but when I put the audio on the higher irq I had no more trouble.
I know that in theory that shouldn't happen because there are two part to
the irq drivers, a stub to answer the IRQ and save enough info to work and
the other part that the os prioritizes and does all the work. So the os
should be able to prioritize by the module name. I just know what I have
found works best.
I have heard the words "in a modern system" too many times. I think any
system can do better audio if it is tuned/tweaked.
--
Len Ovens
www.ovenwerks.net
I recently did an interview regarding the theater company I write music
for. I am posting this because I produce all of my music with Linux audio
(although Windows samplers like Kontakt are used, the real work I describe
here is done with Linux). I also mention MuseScore and Ardour3, here, too
:-)
http://www.art-stream.org/content/flair-dramatic-music-great-scott
(the singing your hear is me, I am a horrible singer but recorded scratch
vocals for the actors, even Autotalent couldn't fix my warbling)
--
Brett W. McCoy -- http://www.brettwmccoy.com
------------------------------------------------------------------------
"In the rhythm of music a secret is hidden; If I were to divulge it, it
would overturn the world."
-- Jelaleddin Rumi
On Tue, 15 Apr 2014, James Mckernon wrote:
> On Mon, Apr 14, 2014 at 2:06 AM, Len Ovens <len(a)ovenwerks.net> wrote:
> I would realy like to stay away from having to use a USB or FW
> audio IF. In fact I would like to be able to continue to use my
> delta 66 for as long as I can before I spend more money :) Â The
>
> Thanks for the useful info in your post. Just to be clear on this part: are
> you saying you don't want to switch to USB/FW solely because you want to
> keep using your delta 66, or because you have some definite preference for
> PCIe over USB/FW devices? If the latter, I wonder why?
USB in audio is limited. Getting clear USB ports interupt wise is not
easy. Audio can not be on a hub or share it's usb with anything else, but
many new MB have no mouse or kb port so the USB is already being used for
that much. The real reason though, is latency. With the pci the latency
can be 1/4 what it can be in USB or FW. That is the lowest seeting jack
for USB or FW is 64/2, but I can run the d66 at 16/2 with no problem on a
well tuned system. This does make a difference for live work. I know that
64/2 seems like very good latency (it is) but remember that the card then
adds another ms in each direction as well as the stage distances on top of
that. That is the time it takes the sound to reach my ear after going
through the computer as a processor and then through the air to my ear.
Maybe that is still not worth worrying about... but even with 30 feet of
cord and no digital delay, I can hear the delay from my playing to the
sound reaching my ear.
--
Len Ovens
www.ovenwerks.net
On Thu, 17 Apr 2014, david wrote:
> On 04/17/2014 09:56 AM, Len Ovens wrote:
>>
>>
>> On Wed, 16 Apr 2014, david wrote:
>>
>>> Then running your sound from stage to backhouse sound board back to
>>> stage and hearing it through headphones would give no latency at all.
>>
>> Nothing I can hear. This is very important becasue if there was
>> noticable delay then stage sound would be ahead of the mains... might
>> give some interesting filtering from being out of phase.
>
> The mains are getting their signal via cable, so they're getting their
> signal as quickly as the monitors on stage. The only change would be
> physical distance from the different speakers, right?
The difference I was thinking of is between a DIed guitar amp and mains as
these and the bass amp (sometimes KB too) have traditionally been faced
towards the audience. We also have some pretty loud vocalists who's
unamplified voice can be heard in the house.
--
Len Ovens
www.ovenwerks.net
