Re: Tascam us-144mkII
Am Sat, 09 Apr 2011 06:35:59 +0200 schrieb ailo ailo...@gmail.com: Specifically, I would be interested to find out if one can get 24 bits and 48kHz out of a card. You can get that out of the Alesis io|2, USB 1, duplex, 24 bit stereo, 48 kHz. It uses actual 24 bit sample format ... so that's 3 B * 2 * 2 * 48000 = 563 KiB per second of payload data that fits well into the limit of USB 1.1 (12 MBit/s = 1464 KiB/s), giving space for whatever overhead is present. But yeah, anything more than that gets really tight. You could have a card with 4 recording channels and 2 playback ... that would be 844 KiB/s ... but then, I don't know how much overhead you have with USB audio and also I'd have to review how duplex operation actually affects the available data rate. Also, looking at the devices that are there, USB1 audio for linux goes up to 24 bit stereo, duplex. And yes, USB 2 devices seem to be sparsely supported. For multichannel recording I got a FireWire device... and FireWire audio can be a bitch to get working right (building a good computer setup). Stereo cards work the best. There are a few multichannel cards that work too, but out of those, usually only those will work well that have specific drivers. The one that seems to work nowadays is the Edirol UA-101, the USB2-sister of my FA-101. There is a driver in ALSA, snd-ua101, that reportedly delivers multichannel work. But what's missing is the software control for the direct monitoring mixer. But then, on my FA-101 setup, I don't use direct monitoring from the box ... we have an analog mixer and separate headphone amp for that, the recording interface is just connected via the inserts on the channels (only the send part). Alrighty then, Thomas. signature.asc Description: PGP signature -- Ubuntu-Studio-users mailing list Ubuntu-Studio-users@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-users
Re: Tascam us-144mkII
Hi Scott, 2011/4/8 Scott Bohon scott.bo...@gmail.com: [...] Should I look for a different interface? Any suggestions for an affordable solution with USB 2.0 or PCI? PCI is preferable. Ciao, Alessio -- Ubuntu-Studio-users mailing list Ubuntu-Studio-users@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-users
Re: Tascam us-144mkII
On Thu, Apr 7, 2011 at 9:42 PM, Scott Bohon scott.bo...@gmail.com wrote: Hello! Thank you all for help on -rt kernel. Now I need to get my USB Audio-MIDI Interface working - Tascam us-144mkII. I think that I need to disable ehci-hcd (USB 2.0). How do I do this? Can it be done per port? Doesn't this slow down my interface, and thus cause more latency? Is there hope for USB 2.0 support? Should I look for a different interface? Any suggestions for an affordable solution with USB 2.0 or PCI? -- Ubuntu-Studio-users mailing list Ubuntu-Studio-users@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-users Hi Scott, I do not have any practical experience with USB, therefore I cannot provide any answers for your technical questions. I can, however, offer some generalized knowledge. I do not believe that USB1 provides enough throughput for acceptable latencies. I believe that USB2 *can* provide decent latencies, but it seems to be rather hit or miss per interface, computer, and OS. I understand that USB3 is designed to provide more throughput than firewire does currently, although we don't know how strictly this standard will be implemented. Ultimately, some people have had very good success achieving acceptable latencies with a USB interface, others have not. For a suggestion, I would recommend a PCI card personally. I concede that it is invasive, requiring you to open your computer, but I feel there is a variety of stable, inexpensive PCI audio interfaces that have a history of working well including the M-Audio Delta series. I believe you can get an M-Audio Delta 44 for around $130 (used for $93) that will provide four inputs and four outputs with a convenient break out box. I forget how long the cable is between the card and the box, something like three feet or four feet. Although you can probably find a firewire interface for slightly more money that would avoid having to open your computer. Others might offer firewire suggestions for comparably priced interfaces that are working with Ubuntu. Cheers, ScottL -- Ubuntu-Studio-users mailing list Ubuntu-Studio-users@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-users
Re: Tascam us-144mkII
On Fri, 2011-04-08 at 08:16 -0500, Scott Lavender wrote: On Thu, Apr 7, 2011 at 9:42 PM, Scott Bohon scott.bo...@gmail.com wrote: Hello! Thank you all for help on -rt kernel. Now I need to get my USB Audio-MIDI Interface working - Tascam us-144mkII. I think that I need to disable ehci-hcd (USB 2.0). How do I do this? Can it be done per port? Doesn't this slow down my interface, and thus cause more latency? Is there hope for USB 2.0 support? Should I look for a different interface? Any suggestions for an affordable solution with USB 2.0 or PCI? -- Ubuntu-Studio-users mailing list Ubuntu-Studio-users@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-users Hi Scott, I do not have any practical experience with USB, therefore I cannot provide any answers for your technical questions. I can, however, offer some generalized knowledge. I do not believe that USB1 provides enough throughput for acceptable latencies. I believe that USB2 *can* provide decent latencies, but it seems to be rather hit or miss per interface, computer, and OS. I understand that USB3 is designed to provide more throughput than firewire does currently, although we don't know how strictly this standard will be implemented. Ultimately, some people have had very good success achieving acceptable latencies with a USB interface, others have not. For a suggestion, I would recommend a PCI card personally. I concede that it is invasive, requiring you to open your computer, but I feel there is a variety of stable, inexpensive PCI audio interfaces that have a history of working well including the M-Audio Delta series. I believe you can get an M-Audio Delta 44 for around $130 (used for $93) that will provide four inputs and four outputs with a convenient break out box. I forget how long the cable is between the card and the box, something like three feet or four feet. Although you can probably find a firewire interface for slightly more money that would avoid having to open your computer. Others might offer firewire suggestions for comparably priced interfaces that are working with Ubuntu. Cheers, ScottL 'Cards meeting the USB 1.1 specification have sufficient data transfer capacity to support high quality sound operation if their circuit design permits. However, USB 1.1 data throughput allows for concurrent use of a limited number of channels and/or limited sampling frequency and/or limited bit depth. For example 2 channels in and 2 channels out at 48 kHz/16 bit, or 2 channels out and no input at 96 kHz/24-bit. For a higher number of channels and/or digital signal parameters, USB 2.0 or higher is needed.' Assumed USB audio devices should be ok, I imagine issues regarding to shared IRQs, printer, mouse, keyboard, webcam, removable media. I've got two Envy24 PCI cards. I auctioned one of those Terratec EWX 24/96 cards at Ebay for around 30 EUR (42 USD). Perhaps Envy24 PCI cards are the cheapest usable cards. Avoid to get a Terratec EWX 24/96, because it doesn't sound good, but try another Envy24 card, if you don't like the Tascam us-144mkII. OTOH, this Tascam might have a better sound quality than any Envy24 elcheapo PCI card and it supports USB 2.0 and USB 1.1: http://www.thomann.de/gb/tascam_us144mk2.htm Pardon, I didn't read the whole thread. Why do you need to use USB 1? Cheers, Ralf -- Ubuntu-Studio-users mailing list Ubuntu-Studio-users@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-users
Re: Tascam us-144mkII
On Fri, Apr 8, 2011 at 9:01 AM, Ralf ralf.mard...@alice-dsl.net wrote: Pardon, I didn't read the whole thread. Why do you need to use USB 1? Cheers, Ralf -- Ubuntu-Studio-users mailing list Ubuntu-Studio-users@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-users Hi Ralf, I don't believe Scott B. wants or is considering a USB1.1 device. I was just giving some background so that he understood that not all USB devices are equal and how they might perform in a simplistic, relative sense. Cheers, ScottL -- Ubuntu-Studio-users mailing list Ubuntu-Studio-users@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-users
Re: Tascam us-144mkII
On Fri, 2011-04-08 at 17:11 -0400, Scott Bohon wrote: On Fri, 2011-04-08 at 09:16 -0500, Scott Lavender wrote: On Fri, Apr 8, 2011 at 9:01 AM, Ralf ralf.mard...@alice-dsl.net wrote: Pardon, I didn't read the whole thread. Why do you need to use USB 1? Cheers, Ralf -- Ubuntu-Studio-users mailing list Ubuntu-Studio-users@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-users Hi Ralf, I don't believe Scott B. wants or is considering a USB1.1 device. I was just giving some background so that he understood that not all USB devices are equal and how they might perform in a simplistic, relative sense. Cheers, ScottL Actually, I do need to disable ehci-hcd (USB 2.0) in order to use my current interface - Tascam us-144. AAt least that is what I see in the ALSA hardware info. But I do not know how to disable ehci-hcd (USB 2.0)! Could not find anything searching Ubuntu docs. Where do I go to disable? Do I just comment out the line with #? Hi Scott B. :) [OT: IMO it's easier to follow mails, if we answer under the quotes] A shot in the dark ... The Internet gives the information that the us-144 and us-144mkII do support 2.0 and 1.1. I guess the driver modules are part of usbcore, dunno if there's a module you can unload, but I guess you don't need to unload a driver. $ lsmod | grep usb does show the loaded modules. There's a module snd-usb-us122l.ko if I run $ modprobe -l | grep usb perhaps you need a special driver for your us-144 too. The command 'hwinfo' might help: $ hwinfo --usb $ hwinfo --sound I e.g. get the output 'Driver Activation Cmd: modprobe snd_ice1712'for my ICE1712 (Envy24) cards. Perhaps hwinfo can tell you what driver you need to load. Connect the device and run 'hwinfo --sound', on some distros you need to be root to do this. -- Ubuntu-Studio-users mailing list Ubuntu-Studio-users@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-users
Re: Tascam us-144mkII
Pretty much every USB device that is supported by Linux are using the usb 1.1 protocol, no matter if they are usb2 cards or not. To my knowledge, all devices that do not need specific drivers under Linux work only if they are usb 1.1 compliant. This usually means, that you get limited performance from usb2 cards. Specifically, I would be interested to find out if one can get 24 bits and 48kHz out of a card. Stereo cards work the best. There are a few multichannel cards that work too, but out of those, usually only those will work well that have specific drivers. I believe the M-Audio Fast Track Ultra is supported with drivers, but I'm not going to recommend any device I haven't tried myself. On 04/08/2011 04:16 PM, Scott Lavender wrote: On Fri, Apr 8, 2011 at 9:01 AM, Ralf ralf.mard...@alice-dsl.net wrote: Pardon, I didn't read the whole thread. Why do you need to use USB 1? Cheers, Ralf -- Ubuntu-Studio-users mailing list Ubuntu-Studio-users@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-users Hi Ralf, I don't believe Scott B. wants or is considering a USB1.1 device. I was just giving some background so that he understood that not all USB devices are equal and how they might perform in a simplistic, relative sense. Cheers, ScottL -- ailo -- Ubuntu-Studio-users mailing list Ubuntu-Studio-users@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-users
