On Sunday 19 August 2007, Robert Jonsson wrote: Thought about that, but no, too much latency [although i guess one could try hacking the USB stuff ;)].. I was rather thinking about attaching a codec to the SPI bus.. But then i'd have to write a driver for it, too.. :) Flo -- Palimm Palimm! http://tapas.affenbande.org

On Sunday 19 August 2007, Jussi Laako wrote: Maybe i miss something but it looks this board is for a certain type of DSP boards [which seem to run ucLinux]. This stuff looks rather costly.. But maybe i miss something obvious. I'm totally new to this embedded stuff :) Flo -- Palimm Palimm! http://tapas.affenbande.org

There's also these: http://mini-itx.com/store/?c=39 I've not worked with that one in particular, but I have with a larger one. They're really easy to work with as they're effectively just generic x86 boards. Some of the larger ones are fanless. I've been wanting to put together an effrects box with one, but just don't have the time. - Steve On 20 Aug 2007, at 05:24, Jon Smirl wrote:

On 20 Aug 2007, at 11:26, Robert Jonsson wrote: I think the ones I worked with might have been EPIA 10000s (1GHz VIA C3), and I did run JACK on them for kicks. I think it worked but I don't remember how it was though, and I didn't test the card on any decent monitors. The onboard sound is generic AC-97 stuff. Some of the models have slow CPUs and very slow FPUs, so beware of those. I was using them for an audio-less video installation, so the testing was just for curiosity. - Steve

On 8/20/07, Florian Schmidt <mista.tapas(a)gmx.net> wrote: It is somewhat computationally intensive to drive USB audio. For example the IPX425 used in the NSLU2 can just barely do it. USB audio runs at 48K and most music is 44.1K, you need to resample it. Make sure the board has DMA support for the USB channel or it is never going to work. -- Jon Smirl jonsmirl(a)gmail.com

On Mon, 2007-08-20 at 19:24 +0200, Florian Schmidt wrote: For the sake of sanity, here is the manual for the chip in question. Note that the floating point co-processor has no divider but on the other hand has a fast Integer Multply Accumulate with four 72bit accumulators. Kind of hellish to make sense out of in a standard C environmenet, but not at all bad for sound processing. Look for chapter two (pdf page 35): http://www.cirrus.com/en/pubs/manual/EP9307_Users_Guide.pdf --

On Sun, 2007-08-19 at 22:40 +0200, Florian Schmidt wrote: Well, costly is often how life is for people who aren't building their own boards or buying dozens to thousands at a time. In fact, I'm curious how much it would cost to actually buy one of those ARM9 boards you mention. They priced from $65 each, but do you have to buy 100 to get that price? I see someone mentioned Efika. As far as I know, there are two potential problems with that board, both are surmountable. First, is basically a PPC 604, not a G4. So, no SIMD. I get the impression that a lot of linux audio software isn't really written to use SSE or Altivec anyway, so this may not be much of a loss. Second, Efika has no on board video and only one PCI slot. Some possible solutions would be to use a serial or USB control panel, and modify any plugins to be controllable via your control panel system. Also, I don't know if any USB->VGA dongles would happen to be supported by linux. Certainly there are several off the shelf character LCD control panels that could be used, and they typically have several GPIO pins that could potentially be attached to a rotary encoder. Alternatively, AVRs that can go between a few rotary encoders and a serial port are pretty cheap, so maybe you could use a Crystal Fontz USB panel in addition to using the serial port for an AVR to rotary encoder system. I also see that elsewhere in the thread someone mentioned using EPIA 10000s, or EPIA 5000s, both MiniITX motherboards, for about $300 or $120 respectively. The upside of either is they have onboard video in addition to a PCI slot, if you want an easy to setup graphics display. Another option that is perhaps a bit more affordable and powerful than any mentioned so far is PCChips makes a board called the V21G. http://www.pcchips.com.tw/PCCWeb/Products/ProductsDetail.aspx?DetailID=384 This is a Flex-ATX board instead of a Mini-ITX board. It is based on the Via C7 instead of the older/slower C3. It has two PCI slots and onboard video. And it is definately less than $75 in the US (Google will show you lots of online retailers). The possible downside to this, is that PCChips is better known in the US as the Elitegroup Computer Systems (ECS). ECS isn't exactly the best quality, but they don't seem to be the worst either. Buy from a place that will give you a refund if you are unhappy, and you are probably OK.

This reminds me that I've been thinking about trying out the gumstix + roboaudio solution for building a simple fx box. They don't have an FPU, which might be a problem, but on the other hand you can put together a 400 MHz ARM processor with an audio DAC and ADC for something like $150, with Linux pre-installed. I've got a gumstix and it's quite nice, but I don't have the roboaudio so I haven't tried it for audio processing yet. Has anyone done so? Steve