sampler DISCOVERY

[Macgyver]

ok so i took the plunge and bought a korg padkontrol.

interesting device... feels good.

attempted to use the padkontrol as a drum machine with Producer

at 1st glance and after some tweaking, i thought i was onto something...
just having a song playing and using the padkontrol things seemed to be working fine


then i tried using the korg padkontrol as well as having someone mix music using a Vestax vci 100
this is where i became disappointed. the gui froze in place (which is normal under the settings i have) and the music being played either became choppy or stopped.. all pads that were hit on the padkontrol sounded at a delayed time interval (after the software was able to process the requests).

seems like Producer can't handle MIDI inputs from 2 different devices at the same time. the time when problems were the worst were when a key on the vci-100 was being pressed repeatedly and a pad or different pads were being struck on the padkontrol at the same time.

so far this makes the sampler with external controller pretty unuseable for me.

i was monitoring system resources and at the time when things would drop out the meter hit 50% or close to it, with MIDI commands coming from both the vci-100 and the padkontrol at the same time.

i still have to see if i get the same results with the time code cd's and the padkontrol

[gakto2009]

Hi Mac,

This is an interesting issue you have come across; i can’t say i am having the same trouble however your setup is very different to my own. Do you use the MIDI input and output on your Stanton Scratch Amp or do you have your VCI-100 and Padkontrol connected via usb?

As the Stanton Scratch Amp has its own MIDI device, i would recommend running your Padkontrol through its interface... i successfully use two MIDI devices with Mixvibes using the MIDI device on an Edirol fa-101 and an M-audio USB UNO interface.

It would be expected that two usb devices should work at the same time, however it may just be your system, i will bring this issue up in the betatesters forum and see if anyone else has had the same issue in the past.

Regards,
Bryan

[UncleVibes]

As the Stanton Scratch Amp has its own MIDI device, i would recommend running your Padkontrol through its interface...

Test it. I suspect some conflict on the usb port or with the name of the devices.

[Macgyver]

well i'll say this.. the test was done on my "light setup"

my light setup consists of laptop, vci-100, & mixvibes u46mkII soundcard.

Everything is connected via usb

As I said both devices can be hooked up....if using 1 device no problem... when i really notice the issue is when commands are being sent from the vci as well as the pad kontrol.
keep in mind that the padkontrol is being used as a drum machine so there are a lot of different MIDI messages coming out of the pad kontrol in a short space of time as well as some MIDI messages coming out of the vci.

I haven't gotten around to testing the main setup, that has the scratch amp as yet. (but i will try the MIDI in as you suggested)

the only other thing i can see doing with this 'light setup' is maybe changing port A to port B on the MIDI window for the padkontrol within mixvibes.

i'm not giving up yet... gonna try a lil more

[gakto2009]

the only other thing i can see doing with this 'light setup' is maybe changing port A to port B on the MIDI window for the padkontrol within mixvibes.

try checking that "OMNI" mode is not selected in the MIDI options, then try setting the output channel of your Padkontrol to another channel (if it supports this feature, normaly done by setting EXT out). i assume it is set to channel 10, try setting it to a lower channel or a higher one.

[taboo]

well heres the thing... i have the same issue as you. allthough i use Producer with the mpd24. i get the same delays. not sure what it is because of. the edirol is connected via firewire and the mpd via usb.

unfortunatly it led me to actually put the mpd to the side and hopefully wait for a "bug-fix" on the next update.. silly me didnt report it but now here u have my voice =)

[gakto2009]

Possible cause of this problem,

From playing about myself with dual MIDI controllers, i have come to the conclusion that latency appears to be the problem.

The best way to understand this is; if you’re using 2 MIDI controllers running at a 4ms latency, it is possible for you to stall the buffer during playback by entering a stream of commands that are less than 4ms apart. By stalling the buffer you are creating a que of commands waiting to be processed which can cause a delay in the final audio reproduction or cause it to drop out all together.

The VCI-100 has allot of buttons that send out single commands, however its jog wheels, faders and rotary faders send out command strings (i.e. moving a fader can generate a possible 127 different MIDI notes, and moving the jog wheel can send the same MIDI note repeatedly with is frequency dependant on how fast the user spins the wheel).

At the moment i don’t see a quick way round this, using this type of setup will work better for some than it will for others as it largely depends on the possible minimum latency of any particular setup.

Anyone else got any thoughts on this issue? We would like to hear from other trying a similar setup!

Regards,
Bryan

[Macgyver]

okay here is an update...after a few hours last night.
I tried testing again with vci-100 and korg padkontrol.
again the same results.

this time i decided to monitor system resources while just using the vci-100 and mixing music. what i noticed was that the cpu usage meter would hit 40 something percent at times (no drop outs in music or anything like that experienced).

doing my previous test this weekend (with both vci-100 & padkontrol), the cpu usage meter would hit maybe about 52% and there would be drop outs in music and delay in the sounding of the pads for the korg padkontrol.

now i begin to say to myself well it seems as if the vci-100 is the resource hog of sorts.

next i played around with settings a little bit & i decided to use the kernel as the driver for the soundcard (u46mkii) ... (and yes i know that the kernel is reccomended for MIDI control, but i didn't need to switch from the asio driver before, no problems so as the old saying goes if it aint broke dont fix it)

after setting up the kernel driver
i monitored system resources with just the vci-100. cpu usage never made it above 20% (definite improvement in that area)
began using the vci-100 as well as the padkontrol & so far so good.
i am able to use the vci-100 and padkontrol as desired know...no noticeable glitches or delay until a new song is loaded into a player...currently mixvibes doesnt seem to take the MIDI input from the padkontrol at that present time (the exact time that the song is being read into memory). but that is bareable, it's only for a second or so.

The asio driver that was used for the soundcard was the u46mkii asio driver, now this driver never really worked for me until the other day, i havent tested it yet but i believe that once my laptop starts up after being off, with the u46mkii connected to it, then the u46mkii driver will be accessible. if i plug the u46mkii into the laptop after the laptop is already on, i don't think that the driver works....and then i would have to use the asio4all driver (i haven't tested it yet to say for certain, but if i remember correctly this is what's been happening).

That being said, I don't know if the asio4all driver would provide better system resources results than the u46mkii driver. So I can't say for certain if the u46mkii driver is a problem or if any asio driver causes high system resource use for this setup.

Anyone else having trouble, maybe this may be helpful for you.

[wazza]

I don't have this problem with my vci & my pcr 500

are you using USB power for all your MIDI devices & your sound card .?????

because if you run to mean usb power devices + run usb power for the sound card your laptop can't give you enough power to run everything at once....( if you run 1usb power device you get fill power if you run 2 devices your laptop will split the power between them.....& so on & so on )....this has always been a problem with usb power & can add latency especially if you have your sound card set to low latency audio ...all the power is given to the sound card and it driver ( ASIO ).... & your MIDI latency can suffer form lack of power

you might need a powered usb hub

[Macgyver]

I don't have this problem with my vci & my pcr 500

are you using USB power for all your MIDI devices & your sound card .?????

because if you run to mean usb power devices + run usb power for the sound card your laptop can't give you enough power to run everything at once....( if you run 1usb power device you get fill power if you run 2 devices your laptop will split the power between them.....& so on & so on )....this has always been a problem with usb power & can add latency especially if you have your sound card set to low latency audio ...all the power is given to the sound card and it driver ( ASIO ).... & your MIDI latency can suffer form lack of power

you might need a powered usb hub

Actually, when i did the test with the kernel, I decided to power the padkontrol from an external power source for the testing. Last night I went back to usb power still using the kernel and all was well still (wasn't a thorough test though).

After reading your thread, I decided to look at the current consumption of all devices that were being usb powered.

I couldn't find any consumption specs for the u46mkii or the western digital passport drive. I found the specs for the padkontrol and the vci-100

each one is about 150mA
if we assume that the u46mkii is 150mA
and the passport is 150mA

add all those up and we have 600mA
100mA more than the 500mA output of the USB bus.

*Good point wazza

Granted all these devices won't be pulling that kind of current continuously it still may play some sort of factor. Last nights test wasn't a thorough one but all seemed well.

I will definitely look into powering the soundcard and the vci-100 off of external power though since those are stationary devices.