Distorted output with all samples

[arsnova]

I just compiled LS from source, and all connections are being made with Jack; however, all loaded samples are distorted, regardless of volume or velocity (I've tried with several of the freely available .gig samples found through the LS resources site.) I've run Jack with sampling rates of 44.1kHz and 48kHz, after finding a post that suggested that the lower rate could be the culprit, but to no avail. Here are my system specifics:

Distro.: Ubuntu Hardy 8.04.1 (32 bit)
Kernel: 2.6.24-19-rt
LinuxSampler: 0.5.1
Jack version: 0.3.2
Front-end: JSampler Fantasia, v. 0.8a
Drivers: ALSA
Soundcard: SB Audigy 2 ZS (notebook)

Not sure if I've left anything out--I'm happy to provide further info. Thanks in advance for any insight and suggestions!

-Alan

[Alex]

arsnova,

Have you tried reducing your main levels in alsamixer, just to see if that kills the distortion?

Alex.

[arsnova]

Hi, Alex--thanks for the reply. I did reduce the mains through Alsamixer, as well as reduce other output levels (all to approximately 60%). I have an internal soundcard that I blacklisted so that all sound routes through the Audigy 2 ZS. Since I'm in a dual-boot situation, I know that the card is functional under WinXP, and the Ubuntu Studio installation is fresh--no faulty ALSA tweaks yet to break the system. I should have mentioned that audio otherwise plays back fine in US--only through the sampler does this occur. I'm, by the way, running Rosegarden; any odds that a wrong setting could cause this? (I adjusted levels to be conservative there, as well.)

Thanks again!
-Alan

[neuralnet]

Hi Alan/Alex,
After a frustrating start I'd finally managed to get the debs compiled & installed, only to find I have the same problem. I'm trying to set up under Ubuntu Hardy with Rosegarden as well, but using a SoundBlaster Live instead of an Audigy. Similarly sound is fine under WinXP, and in Ubuntu if coming from any source other than Linuxsampler.
Seems unrelated to volume as is grungy and distorted all the way. Sounds very much like it's playing at the wrong (low) bitrate. Tried 44k & 48k in JACK, no difference. Tried downloading the concert grand GIG instead of one I made myself - same. Did you manage to improve things Alan ? TBH I think I may be better off saving the hair I have left & buying a hardware sampler at this rate..

[arsnova]

I'm still relegated to a dual-boot situation for the moment, so I'm sorry to say I don't have a solution yet. For grins, since the installation was new, I just re-installed the OS and Linuxsampler (much easier the second time around) again--this would have been necessary to fix an upgrade (er, broken package), anyway. I *can* say that the problem is reproducible on this machine, since the distorted output remains. Thanks for reviving this--I've searched other posts and haven't had much luck. Any changes, and I'll post news to this thread.

-Alan

[neuralnet]

Seems like we're not the only ones to have this problem Alan... not confined to recent builds either it seems - although I can't find a solution either. If we can pin it down further, I'm running a 32 bit version of Hardy on an AMD 4400 64bit dual core with 2gb RAM. I've tried jsampler instead of qsampler and can confirm the problem remains.. so the problem is clearly with linuxsampler/libs/or the routing itself not the interface proggy.

[kaimerra]

I'm hoping we can revive this thread and find a solution because I am having this issue as well. I just did a fresh install of 64studio 2.1 and made my own gig set and started up Qsynth to hear all distorted output. This is running jack at 44.1 on a maudio ozone. I am doing a round of updates which include an update to Qsynth, so I will see if it happens after that and try jack at 48k and post my results.

[kaimerra]

Okay, so I just tried a bunch of variations on my setup. I tried Qsampler with jack at 44.1 and 48 with same result, Alsa with 44.1 and 48 with same result. So I then downloaded the source for libgig and linuxsampler and compiled those myself but used binaries for lscp and qsampler to same result with all jack/alsa sampling frequencies. I am running out of ideas so I am downloading the maestro concert grand instrument from the website to try that to eliminate it being my gig setup. I saw someone mention on a lau thread it might be related to a bug in Alsa, does anyone have any evidence of this? I might try installing a backport/testing version of alsa to see if that helps.

cheers

[Alex]

For what it's worth, i have a few 'hot' orchestral gig files that need some stern gain reduction.

My primary oboe samples need to be as low as 15% in LS to come out clear of any distortion or noise, so don't be afraid to crank things down quite a bit.

The single biggest issue i dealt with was the overall volume for the computer.
I cut this back to 70%, then readjusted app volumes and it worked ok.

If you open a terminal, and type in

alsamixer

then check your levels there. It may be the bass is too high, or the treble, and that's not helping at all. Take everything down to a non distorted level, then gradually lift each component until you get a problem, you'll have a better chance of identifying where the issue is.
you should also check the alsa site and irc channels for any reported problems with your particular soundcard.



Alex.

[kaimerra]

I tried turning levels down and attenuating my gig instrument in its setup. It is not sound card related because I tried it using alsa on my internal Cirrus Logic Sound Fusion CS46XX on one laptop and my other laptop using alsa on an intel-hda internal card and using jack with an maudio ozone usb and roland edirol ua-4fx usb sound card. All the same result. I also upgraded to a newer alsa version, 1.0.17 withthe same result.
The distortion is varied, because some samples I can make out and are just crackly or garbled, and some samples sqeel while others are pure static.
That maestro grand gig sample has finished downloading so i cam going to try loading that up and see what happens.

B