[LAU] Re: Jack Frames/Period setting with Firewire

install lowlatency kernel &/or liquorix kernel. This is no longer true. Generic kernels contain more or less the entire RT-PREEMPTION patch set these days, and will function at least well as the so-called low-latency kernel. If you want to do better, you need the "RT" kernel provided by your distro, not the "low latency" one. On Tue, Apr 8, 2025 at 8:07 AM Juan P C <audioprof2002(a)hotmail.com> wrote: > #1. most computers cannot do better than 7 or 8 miliseconds AD-DA > latency... > Buffer size is different in different interfaces: PCI, USB, FireWire... > ADC & DAC chips have more latency if are 1st gen "older", > > USB: 256x2 is much better vs. 128x5 > has the same audio latency measured with an oscilloscope, > but CPU works relaxed with 256x2 = less Xruns. > > install lowlatency kernel &/or liquorix kernel. > > #3. RME hdsp 9632 pci alsa driver works ok up to 2013, > since 2013, source code has small "Cosmic Ray Bit Flips", > RME Alsa driver has weird glitches, > because Alsa driver is Not activated permanently, > driver activates every-time i pay an audio file, and deactivates when > audio stops, > the first 7 seconds of audio buffer are corrupted. > > but Jack is Activated continuously, > it does Not matter. > > #4. when using low latency: > requires CPU running Fast all the time "Performance" mode, > install cpupower-gui > or similar > and > CPU-X > to verify CPU speed. > > some Linux Generic Kernels, when are "On Demand" > does Not allow Single core CPU to reach 100%, are limited to 50%. > "to save battery power." > > #5. Pulse audio requires manual configuration to change sample rate to > 48KHz or more, > and Bit Depth from 16 to 24 or more. > if you play a 48KHz-24-Bits file using PulseAudio, > PulseAudio will convert to 44.1KHz,-16-Bits > same: > some versions of VLC only play at 44.1KHz has a Bug, > even if PulseAudio .config is set ok. > > #6. > i have the temptation to buy a Digidesign 003 > would be interesting to test. > > Digi002 had terrible sound, requires too much modifications. > Digi001 had nice sound, transparent, PCI but does Not have Alsa driver. > > ________________________________________ > From: Florian Paul Schmidt <mista.tapas(a)gmx.net> > Sent: Tuesday, April 8, 2025 2:02 AM > To: linux-audio-user(a)lists.linuxaudio.org; Jay Thomas > Subject: [LAU] Re: Jack Frames/Period setting with Firewire > > On April 7, 2025 8:36:15 PM GMT+02:00, Jay Thomas <jayt0808(a)gmail.com> > wrote: > >Hello > > > >I am having difficulty setting Frames/Period for Jack at 128 to keep the > >system from having stuttering audio quality. The highest I can go is 64 > >but that is not high enough to resolve the stuttering issue. Jack > >complains of ALSA not being able to set the parameters: "ERROR: ALSA: > >cannot set hardware parameters for capture" > > > >The driver being used is snd-fireworks. This module has a config > parameter > >called resp_buf_size that can be set to 4096 maximum. So when I set this > >parameter to 4096, I still have trouble setting the Frames/Period in Jack > >to 128. It would seem that one would expect that 4096 would be good > enough > >since I am using an AudioFire device with 16 channels being sent over the > >FW bus. 1 sample = 4 bytes. 4 bytes x 16 channels x 128 = 4096. So this > >figure of 4096 bytes is enough to hold 128 samples of 16 channels of > audio. > > > >Is there another driver module configuration parameter that I need to > >change instead of the snd-fireworks parameter such that ALSA will be able > >to set the requested buffer size that propagates down from Jack config? > > > > Hi, sorry for top-posting. > > A buffer needs to hold at least two periods for jackd. And two times 64 is > 128. > > Regards, > FPS > _______________________________________________ > Linux-audio-user mailing list -- linux-audio-user(a)lists.linuxaudio.org > To unsubscribe send an email to > linux-audio-user-leave(a)lists.linuxaudio.org > _______________________________________________ > Linux-audio-user mailing list -- linux-audio-user(a)lists.linuxaudio.org > To unsubscribe send an email to > linux-audio-user-leave(a)lists.linuxaudio.org >