Hi, I have a "one off" project that has to take a standard stereo 24bit audio stream at 192KHz sample rate, that I need to convert into mono. I've browsed AD, TI etc, and the eval kits seem overkill. I've seen the alesis AL3101 4$ DSP's but they only go up to 48K sample rate http://www.wavefrontsemi.com/products.html Any suggestion of a simple evaluation kit that will suit my needs? thanks martin Serious error. All shortcuts have disappeared. Screen. Mind. Both are blank.
Simple DSP eval kit for audio
Started by ●December 5, 2004
Reply by ●December 5, 20042004-12-05
martin griffith wrote:> Hi, > I have a "one off" project that has to take a standard stereo 24bit > audio stream at 192KHz sample rate, that I need to convert into mono. > > I've browsed AD, TI etc, and the eval kits seem overkill. > I've seen the alesis AL3101 4$ DSP's but they only go up to 48K sample > rate > http://www.wavefrontsemi.com/products.html > > Any suggestion of a simple evaluation kit that will suit my needs? > > thanks > > > > martin > > Serious error. > All shortcuts have disappeared. > Screen. Mind. Both are blank.It seems to me that all you need to do is add the two channels together and divide by two, with rounding. A 24-bit adder (or three cascaded 8-bit adders) will do that handily. Take the most-significant output bit from carry out, tie carry in high to force rounding, and ignore the output LSB. That is the easy part. Whether you use an adder chip or a processor, you will want a clock that matches the signal. How will you get it? Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Reply by ●December 6, 20042004-12-06
How about a PC, or does it need to be an eval board? A PC with 192K sound hardware would make a platform that was easy to develop on. Is your audio signal already digital, or do you need to convert it from/to analog? The 192K part is probably going to be the sticking point. The eval boards I know of only go up to 96K. And those that do 192K probably are going to have a lot more processing than you need. It's a bit of an odd requirement--very high end audio spec, but a trivial amount of processing. Maybe an FPGA or something? "martin griffith" <martingriffith@yahoo.co.uk> wrote in message news:4ja6r09mo7jhsc7jc0h1dep076kuebuhba@4ax.com...> Hi, > I have a "one off" project that has to take a standard stereo 24bit > audio stream at 192KHz sample rate, that I need to convert into mono. > > I've browsed AD, TI etc, and the eval kits seem overkill. > I've seen the alesis AL3101 4$ DSP's but they only go up to 48K sample > rate > http://www.wavefrontsemi.com/products.html > > Any suggestion of a simple evaluation kit that will suit my needs? > > thanks
Reply by ●December 6, 20042004-12-06
martin griffith <martingriffith@yahoo.co.uk> wrote in news:4ja6r09mo7jhsc7jc0h1dep076kuebuhba@4ax.com:> Hi, > I have a "one off" project that has to take a standard stereo 24bit > audio stream at 192KHz sample rate, that I need to convert into mono. > > I've browsed AD, TI etc, and the eval kits seem overkill. > I've seen the alesis AL3101 4$ DSP's but they only go up to 48K sample > rate > http://www.wavefrontsemi.com/products.html > > Any suggestion of a simple evaluation kit that will suit my needs? > > thanks > > > > martin > > Serious error. > All shortcuts have disappeared. > Screen. Mind. Both are blank.You can do this our dspstak 21262sx DSP Engine (ADSP-21262 based) and an appropriate I/O card. If you want analog in and out, we have a stereo codec that samples at 192k called a dspstak c192k22. We also have a dspstak S/PDIF card for digital inputs and outputs. -- Al Clark Danville Signal Processing, Inc. -------------------------------------------------------------------- Purveyors of Fine DSP Hardware and other Cool Stuff Available at http://www.danvillesignal.com
Reply by ●December 6, 20042004-12-06
Al Clark wrote:> You can do this our dspstak 21262sx DSP Engine (ADSP-21262 based) and an > appropriate I/O card. If you want analog in and out, we have a stereo codec > that samples at 192k called a dspstak c192k22. We also have a dspstak > S/PDIF card for digital inputs and outputs.Al, with your parts would I be able to configure a 24 bit 96k four analog in, 2 stereo digital out mirrored on four analog out system with enough processing power to do overlap-save/add convolution of the four inputs against four groups of four 8k floating point FIR's (16 total), each group summed back to four outputs? The real time FFT's and IFFT's would only be four because the FIR matrix is static. If 96k is too much, 48k might could suffice. If so, what might such a setup cost? Units and quantities. I know I could and probably should ask this via direct email but thought it might be of interest to others. Thanks, Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein
Reply by ●December 7, 20042004-12-07
On Sun, 5 Dec 2004 21:46:55 -0800, in comp.dsp "Jon Harris" <goldentully@hotmail.com> wrote:>How about a PC, or does it need to be an eval board? A PC with 192K sound >hardware would make a platform that was easy to develop on. Is your audio >signal already digital, or do you need to convert it from/to analog? > >The 192K part is probably going to be the sticking point. The eval boards I >know of only go up to 96K. And those that do 192K probably are going to have a >lot more processing than you need. It's a bit of an odd requirement--very high >end audio spec, but a trivial amount of processing. Maybe an FPGA or something? > >"martin griffith" <martingriffith@yahoo.co.uk> wrote in message >news:4ja6r09mo7jhsc7jc0h1dep076kuebuhba@4ax.com... >> Hi, >> I have a "one off" project that has to take a standard stereo 24bit >> audio stream at 192KHz sample rate, that I need to convert into mono. >> >> I've browsed AD, TI etc, and the eval kits seem overkill. >> I've seen the alesis AL3101 4$ DSP's but they only go up to 48K sample >> rate >> http://www.wavefrontsemi.com/products.html >> >> Any suggestion of a simple evaluation kit that will suit my needs? >> >> thanks >I'll start off with recording onto a PC, muck around with the signal in CoolEdit to mono the signal. But the client wants minimum delay, realtime, and I dont actually know what he wants to do with the signal! Its using hi end audio grade ADC for industrial measurment, but thats all I know. I might end up using a FPGA or something, but thats an area I know little about (at the moment) Thanks martin Serious error. All shortcuts have disappeared. Screen. Mind. Both are blank.
Reply by ●December 7, 20042004-12-07
I think it's called "Audition" now after Adobe purchased Syntrillium... -- Stephan M. Bernsee http://www.dspdimension.com
Reply by ●December 7, 20042004-12-07
Bob Cain <arcane@arcanemethods.com> wrote in news:cp314d02hqk@enews2.newsguy.com:> > > Al Clark wrote: > >> You can do this our dspstak 21262sx DSP Engine (ADSP-21262 based) and >> an appropriate I/O card. If you want analog in and out, we have a >> stereo codec that samples at 192k called a dspstak c192k22. We also >> have a dspstak S/PDIF card for digital inputs and outputs. > > Al, with your parts would I be able to configure a 24 bit > 96k four analog in, 2 stereo digital out mirrored on four > analog out system with enough processing power to do > overlap-save/add convolution of the four inputs against four > groups of four 8k floating point FIR's (16 total), each > group summed back to four outputs? The real time FFT's and > IFFT's would only be four because the FIR matrix is static. > > If 96k is too much, 48k might could suffice. > > If so, what might such a setup cost? Units and quantities. > I know I could and probably should ask this via direct email > but thought it might be of interest to others. > > > Thanks, > > BobHi Bob, I appreciate the opening for a shameless commerce plug;-) WARNING: WHAT FOLLOWS IS EXACTLY THAT! Starting with the I/O, we have a few possibilities, not perfect 1. We have an upcoming 96K 24 bit I/O module that uses an Analog Devices' AD1836A. It samples at 96k (2 inputs) or 48k (4 inputs). There are 6 audio outputs. It is compatible with our dspstak S/PDIF card. This card has a digital receiver and 4 transmitters. 2. Our dspstak c96k44 I/O module is a 4 input & 4 output card (can be combined for 8 in 8 out) that samples to 96k. It is not compatible with the dspstak S/PDIF I/O module. 3. If you need a sufficient number of I/O modules, we can design a custom I/O Module (or you can design your own). Our dspstak DSP Engine cards are based on third generation SHARC DSPs. We have products based on the ADSP-21262 and very soon the ADSP-21364 & ADSP- 21261. FFTs are very efficient. It only takes a few instructions per sample per FFT so computation power is not an issue. The ADSP-21364 has 3M bits of memory. This may or may not be enough memory with overlap and add. Here is a link to optimized SHARC FFT code: http://www.analog.com/processors/processors/sharc/technicalLibrary/codeExam ples/2126x_code.html Pricing is going to vary depending on the specific implementation. Single quantity might be about $1000 for a complete 3 board system. Our business is aimed at small and medium production opportunities from 1 - 500 systems. Prices fall quickly as volume increases. Our price list is on our web site. This will give you a basic feel for our discount schedule and typical board prices. -- Al Clark Danville Signal Processing, Inc. -------------------------------------------------------------------- Purveyors of Fine DSP Hardware and other Cool Stuff Available at http://www.danvillesignal.com
Reply by ●December 7, 20042004-12-07
martin griffith wrote: ...> I'll start off with recording onto a PC, muck around with the signal > in CoolEdit to mono the signal. But the client wants minimum delay, > realtime, and I dont actually know what he wants to do with the > signal! > Its using hi end audio grade ADC for industrial measurment, but thats > all I know. > I might end up using a FPGA or something, but thats an area I know > little about (at the moment)Why is a hardware adder ruled out? Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Reply by ●December 7, 20042004-12-07
In article <31m08gF3cd7idU2@individual.net>, Jerry Avins <jya@ieee.org> wrote:>Why is a hardware adder ruled out?Hardware requires a different set of tools to fabricate and debug: 'scopes, logic analyzers, and, these days, surface mount tools, probes, and magnifiers. Not sure what the cost differential is between the above and the ICE, JTAG and/or compile/debug tools needed for a software solution on prefab or general purpose hardware (FPGA, DSP, or embedded CPU development kit, or PC). Furthermore, if you find that you have some design specification "oversight", a software modification turn is often faster. Hardware solutions can be smaller and cheaper, but the usual rule is to go that route only if there is a significant performance advantage, or if the volume-cost advantage outweighs the NRE costs and design/manufacturing delay (or if you just like tinkering with wires :). IMHO. YMMV. -- Ron Nicholson rhn AT nicholson DOT com http://www.nicholson.com/rhn/ #include <canonical.disclaimer> // only my own opinions, etc.
