Forums

Do-it-yourself audio effects device ?

Started by Tomi Kinnunen July 11, 2007
Dear DSP and audio gurus,

I have a few years experience with DSP theory and practise,
mostly in Matlab and related to speech processing.
My original background is in computer science; I am familiar with 
some "real" programming also :-) I've implemented some simple audio effects 
like EQ, chorus/flanger, and compressor. 

I've been thinking to extend my DSP and programming know-how to some 
hardware-oriented / embedded / realtime programming. I was thinking 
maybe programming some audio effects to somekind of chip would
be good project to learn some hardware-oriented realtime 
signal processing. What do you think?

I am interested to purchase somekind of chip/board that I can 
connect easily to a computer (e.g. via USB), where I can 
program my own stuff. However, this device should be operating 
totally without computer after it has been programmed -- e.g., 
to be used as a guitar or karaoke effect. What is this kind of 
device called, does there exist one? :-) Please help me to get 
started with some basic terminology so that I know what I need to 
look for.

Thank you !
Tomi Kinnunen
Tomi Kinnunen wrote:
> I am interested to purchase somekind of chip/board that I can > connect easily to a computer (e.g. via USB), where I can > program my own stuff. However, this device should be operating > totally without computer after it has been programmed -- e.g., > to be used as a guitar or karaoke effect.
An eval board from a DSP chip vendor is likely to do what you're asking. Check for appropriate audio interfaces before purchasing though. A better solution could be one of the offerings from Danville Signal Processing http://www.danvillesignal.com/ - the principal there is Al Clark, a regular here on comp.dsp. Good luck, and have fun with this. -- Jim Thomas Principal Applications Engineer Bittware, Inc jthomas@bittware.com http://www.bittware.com (603) 226-0404 x536 Failure is always an option
Tomi Kinnunen wrote:
> Dear DSP and audio gurus, > > I have a few years experience with DSP theory and practise, > mostly in Matlab and related to speech processing. > My original background is in computer science; I am familiar with > some "real" programming also :-) I've implemented some simple audio effects > like EQ, chorus/flanger, and compressor. > > I've been thinking to extend my DSP and programming know-how to some > hardware-oriented / embedded / realtime programming. I was thinking > maybe programming some audio effects to somekind of chip would > be good project to learn some hardware-oriented realtime > signal processing. What do you think? > > I am interested to purchase somekind of chip/board that I can > connect easily to a computer (e.g. via USB), where I can > program my own stuff. However, this device should be operating > totally without computer after it has been programmed -- e.g., > to be used as a guitar or karaoke effect. What is this kind of > device called, does there exist one? :-) Please help me to get > started with some basic terminology so that I know what I need to > look for. > > Thank you ! > Tomi Kinnunen
Most DSP evaluation kits (e.g. ADI TigerSharc TS201, Freescale (nee Motorola) DSP56303EVM) include some flash programmable memory for standalone use. I am sure hardware experts on this list will enumerate many others. The DSP56303 is widely used in Pro Audio devices, not least in ProTools, so even if there are technically more advanced chips around, experience programming that chip will open up possibilities of making TDM plugins for Pro Tools (assuming you can persuade them to give you an SDK licence...). Sharcs are used in teh Creamware Scope and Pulsar cards. Richard Dobson
On Jul 11, 9:55 am, Tomi Kinnunen <tki...@cs.joensuu.fi> wrote:
> Dear DSP and audio gurus, > > I have a few years experience with DSP theory and practise, > mostly in Matlab and related to speech processing. > My original background is in computer science; I am familiar with > some "real" programming also :-) I've implemented some simple audio effects > like EQ, chorus/flanger, and compressor. > > I've been thinking to extend my DSP and programming know-how to some > hardware-oriented / embedded / realtime programming. I was thinking > maybe programming some audio effects to somekind of chip would > be good project to learn some hardware-oriented realtime > signal processing. What do you think? > > I am interested to purchase somekind of chip/board that I can > connect easily to a computer (e.g. via USB), where I can > program my own stuff. However, this device should be operating > totally without computer after it has been programmed -- e.g., > to be used as a guitar or karaoke effect. What is this kind of > device called, does there exist one? :-) Please help me to get > started with some basic terminology so that I know what I need to > look for. > > Thank you ! > Tomi Kinnunen
You will need a DSP starter kit, or DSK. The TMS320C6713 DSK from Spectrum Digital will do it for you: http://focus.ti.com/docs/toolsw/folders/print/tmdsdsk6713.html If you want to have an ability to load and control your DSP code from a PC-based GUI application you will also need HPI daugther card from Educational DSP, LLC: http://www.educationaldsp.com/stockproduct_dsk6xxxhpi.htm This setup works just fine, plenty of CPU cycles to do any audio effect in real time... Haven't tried to boot and run it in standalone mode yet. It should be possible though...
"Jim Thomas" <jthomas@bittware.com> wrote in message
news:1399raltddmdf70@corp.supernews.com...
> Tomi Kinnunen wrote: > > I am interested to purchase somekind of chip/board that I can > > connect easily to a computer (e.g. via USB), where I can > > program my own stuff. However, this device should be operating > > totally without computer after it has been programmed -- e.g., > > to be used as a guitar or karaoke effect. > > An eval board from a DSP chip vendor is likely to do what you're asking. > Check for appropriate audio interfaces before purchasing though. > > A better solution could be one of the offerings from Danville Signal > Processing http://www.danvillesignal.com/ - the principal there is Al > Clark, a regular here on comp.dsp. > > Good luck, and have fun with this. > > -- > Jim Thomas Principal Applications Engineer Bittware, Inc > jthomas@bittware.com http://www.bittware.com (603) 226-0404 x536 > Failure is always an option
The offerings from Danville seem a bit pricey for a hobbyist, particularly when you consider that he also needs a development environment, RTOS etc. I have no personal experience with the following, but at least one other poster has reported good experiences (although in an environment different from audio): An NXP LPC 2138 mounted on an Olimex evaluation board: http://www.olimex.com/dev/lpc-mt-2138.html . Also from Olimex, the parallel port JTAG debugger / programmer. For the compiler / debugger environment: Rowley Cross Studio for ARM - Said to be easy to use for anyone that knows Visual Studio and is very reasonable in terms of price. The compiler is based on the open source one, so all the examples for the LPC2xxx can be compiled on there. FreeRTOS realtime OS: http://www.freertos.org . There is supposedly a port for the Rowley IDE and LPC2138. It's for a Kiel evaluation board, but it's supposedly straightforward to modify it for the Olimex one. The evaluation board was about $80, the JTAG about $30 and Rowley about $150. Overall it was recommended for someone considering getting started in micros for the first time. Any comments on this?
On 11 jul, 10:10, "Michael K. O'Neill"
<mikeathon2...@nospam.hotmail.com> wrote:
> "Jim Thomas" <jtho...@bittware.com> wrote in message > > news:1399raltddmdf70@corp.supernews.com... > > > > > > > Tomi Kinnunen wrote: > > > I am interested to purchase somekind of chip/board that I can > > > connect easily to a computer (e.g. via USB), where I can > > > program my own stuff. However, this device should be operating > > > totally without computer after it has been programmed -- e.g., > > > to be used as a guitar or karaoke effect. > > > An eval board from a DSP chip vendor is likely to do what you're asking. > > Check for appropriate audio interfaces before purchasing though. > > > A better solution could be one of the offerings from Danville Signal > > Processinghttp://www.danvillesignal.com/- the principal there is Al > > Clark, a regular here on comp.dsp. > > > Good luck, and have fun with this. > > > -- > > Jim Thomas Principal Applications Engineer Bittware, Inc > > jtho...@bittware.com http://www.bittware.com (603) 226-0404 x536 > > Failure is always an option > > The offerings from Danville seem a bit pricey for a hobbyist, particularly > when you consider that he also needs a development environment, RTOS etc. > > I have no personal experience with the following, but at least one other > poster has reported good experiences (although in an environment different > from audio): > > An NXP LPC 2138 mounted on an Olimex evaluation board:http://www.olimex.com/dev/lpc-mt-2138.html. Also from Olimex, the parallel > port JTAG debugger / programmer. > > For the compiler / debugger environment: Rowley Cross Studio for ARM - Said > to be easy to use for anyone that knows Visual Studio and is very reasonable > in terms of price. The compiler is based on the open source one, so all the > examples for the LPC2xxx can be compiled on there. > > FreeRTOS realtime OS:http://www.freertos.org. There is supposedly a port > for the Rowley IDE and LPC2138. It's for a Kiel evaluation board, but it's > supposedly straightforward to modify it for the Olimex one. > > The evaluation board was about $80, the JTAG about $30 and Rowley about > $150. Overall it was recommended for someone considering getting started in > micros for the first time. > > Any comments on this?- Ocultar texto de la cita - > > - Mostrar texto de la cita -
Hello, The solution is a SigmaDSP by ADI: www.analog.com/sigmadsp Cheers.
"Michael K. O'Neill" <mikeathon2000@nospam.hotmail.com> wrote in
news:Kp6li.8069$bz7.1241@newssvr22.news.prodigy.net: 

> > "Jim Thomas" <jthomas@bittware.com> wrote in message > news:1399raltddmdf70@corp.supernews.com... >> Tomi Kinnunen wrote: >> > I am interested to purchase somekind of chip/board that I can >> > connect easily to a computer (e.g. via USB), where I can >> > program my own stuff. However, this device should be operating >> > totally without computer after it has been programmed -- e.g., >> > to be used as a guitar or karaoke effect. >> >> An eval board from a DSP chip vendor is likely to do what you're >> asking. >> Check for appropriate audio interfaces before purchasing though. >> >> A better solution could be one of the offerings from Danville Signal >> Processing http://www.danvillesignal.com/ - the principal there is Al >> Clark, a regular here on comp.dsp. >> >> Good luck, and have fun with this. >> >> -- >> Jim Thomas Principal Applications Engineer Bittware, Inc >> jthomas@bittware.com http://www.bittware.com (603) 226-0404 x536 >> Failure is always an option > > The offerings from Danville seem a bit pricey for a hobbyist, > particularly when you consider that he also needs a development > environment, RTOS etc. >
I agree that an eval board from one of the DSP manufacturers may be a good choice. Analog Devices is the dominant player in audio (discounting telephony). I would go this route over TI or NXP. The major cost of any board purchase will be the time spent using it. I think you will get more benefit by developing skills with a popular family of devices. Eval boards typically include some dev tools. In the ADI case, this includes a Kit version of Visual DSP and a built-in debugger (ICE). We license the same debugger from ADI and also include a KIT license of Visual DSP with our dspstak 21369 with ICE boards. Our dev boards differ from an eval board in that they are designed as a dev platform for our production boards. The production boards are less expensive than eval boards and more flexible. Our customers are typically using our boards for small and medium volume production runs where the cost of developing and manufacturing a full custom board is more expensive than buying ours. We usually lose money when we sell a dev board. This is due primarily to the free support we give our customers. We are betting with our customers that they will need our production boards after they develop their product. -- Al Clark Danville Signal Processing, Inc. -------------------------------------------------------------------- Purveyors of Fine DSP Hardware and other Cool Stuff Available at http://www.danvillesignal.com
> I have no personal experience with the following, but at least one > other poster has reported good experiences (although in an environment > different from audio): > > An NXP LPC 2138 mounted on an Olimex evaluation board: > http://www.olimex.com/dev/lpc-mt-2138.html . Also from Olimex, the > parallel port JTAG debugger / programmer. > > For the compiler / debugger environment: Rowley Cross Studio for ARM - > Said to be easy to use for anyone that knows Visual Studio and is very > reasonable in terms of price. The compiler is based on the open source > one, so all the examples for the LPC2xxx can be compiled on there. > > FreeRTOS realtime OS: http://www.freertos.org . There is supposedly a > port for the Rowley IDE and LPC2138. It's for a Kiel evaluation board, > but it's supposedly straightforward to modify it for the Olimex one. > > The evaluation board was about $80, the JTAG about $30 and Rowley > about $150. Overall it was recommended for someone considering > getting started in micros for the first time. > > > Any comments on this? > >

Al Clark wrote:


> I agree that an eval board from one of the DSP manufacturers may be a > good choice. Analog Devices is the dominant player in audio (discounting > telephony).
Analog Devices is the dominant DSP player in the "Everything Else" sector of the market. The big chunks like military, medical, entertainment are taken by the other companies, leaving "everything else" to ADI. It is sad, because ADI DSPs have a very sensible architecture compared, say, to TI. The ADI documentation is also better. It is easier to start working with AD DSP.
> We usually lose money when we sell a dev board. This is due primarily to > the free support we give our customers. We are betting with our customers > that they will need our production boards after they develop their > product.
I have developed RTOS for BlackFin (keeping in mind the portability to the other CPUs). It was successfully used in the several projects. Vladimir Vassilevsky DSP and Mixed Signal Design Consultant http://www.abvolt.com
Vladimir Vassilevsky wrote:
> > > Al Clark wrote: > > >> I agree that an eval board from one of the DSP manufacturers may be a >> good choice. Analog Devices is the dominant player in audio >> (discounting telephony). > > Analog Devices is the dominant DSP player in the "Everything Else" > sector of the market. The big chunks like military, medical, > entertainment are taken by the other companies, leaving "everything > else" to ADI.
Strange list. Military and medical are definitely in the everything else category. Pretty low volumes, and ADI have done well at them.
> It is sad, because ADI DSPs have a very sensible architecture compared, > say, to TI. The ADI documentation is also better. It is easier to start > working with AD DSP. > >> We usually lose money when we sell a dev board. This is due primarily >> to the free support we give our customers. We are betting with our >> customers that they will need our production boards after they develop >> their product. > > I have developed RTOS for BlackFin (keeping in mind the portability to > the other CPUs). It was successfully used in the several projects.
It intrigues me how many non-DSP people are using the Blackfin, especially since they started providing solid uCLinux support for it. Regards, Steve
Hi Al,

Al Clark napisa&#2013266099;(a):
(...)
> I agree that an eval board from one of the DSP manufacturers may be a > good choice. Analog Devices is the dominant player in audio (discounting > telephony). I would go this route over TI or NXP. The major cost of any > board purchase will be the time spent using it. I think you will get more > benefit by developing skills with a popular family of devices.
I agree, that The SHARC evalutaion board is the best platform for Tomi. First, he should choose floating point architecture to avoid problems with fixed point implementation of audio algorithms, and the second, ADI SHARC tools are build in Matlab. Why not TI C6713 ? Its not so perfect for audio (hardware architecture, easy of programming) like SHARC. Anyway, TI chips are cheapest, so may be interesting for big volume production, but this is not the case. Best regards Roman Rumian http://www.analog.com/en/epHSProd/0,,21369-HARDWARE,00.html