DSP Board Completed (DSP56371)

[rfbrw]

Originally Posted by tritosine

I tought you just sent him to develop DDS clock generation, now I see the destination goes straight into jitter-hell.

I didn't know you did comedy. Thanks for that.

[tritosine]

Perhaps you want to tell Hypex about their butchering practices by using an ASRC ?

[rfbrw]

Originally Posted by tritosine

Perhaps you want to tell Hypex about their butchering practices by using an ASRC ?

Why ? If I had a product to sell and a price point to meet I might do the same.

[tritosine]

ok Yoshy, I suppose you do want realtime operation, so thats your choice, use an asrc and save a lot of time and effort, and admit how useful is a fix sample rate, - Or go the other way and stay in the sacred circle of bit-perfectness whether the opposite means butchering or not really . I would do the ASRC and crossover combo anyway, just like Hypex . Whether IIR or FIR now thats another debate, it really depends on what you want, and there are some tricks you can play with FIR, and you goin to hate it for subwoofer usage, so, IIR is better allround.

[Yoshy]

Originally Posted by tritosine

ok Yoshy, I suppose you do want realtime operation, so thats your choice, use an asrc and save a lot of time and effort, and admit how useful is a fix sample rate, - Or go the other way and stay in the sacred circle of bit-perfectness whether the opposite means butchering or not really . I would do the ASRC and crossover combo anyway, just like Hypex . Whether IIR or FIR now thats another debate, it really depends on what you want, and there are some tricks you can play with FIR, and you goin to hate it for subwoofer usage, so, IIR is better allround.

Except, this DSP will probably never run a crossover and if it were to I'd go with IIR. This DSP is simply for simple effects, volume control and eq. I wouldn't use an ASRC - I'd just use the same sampling frequency everywhere; it's much more simpler.

[tritosine]

I'd think you need the last drop of DNR to have good digital volume control. ASRC can throw jitter out (that means DNR), your dsp can't.

[rfbrw]

Originally Posted by Yoshy

Except, this DSP will probably never run a crossover and if it were to I'd go with IIR. This DSP is simply for simple effects, volume control and eq. I wouldn't use an ASRC - I'd just use the same sampling frequency everywhere; it's much more simpler.

Have had a look at the AD and Freescale application notes on eq and effects ?

[Yoshy]

Originally Posted by rfbrw

Have had a look at the AD and Freescale application notes on eq and effects ?

I look at some, I don't know if we're talking about the same ones. The ones I looked at targeted the whole 56k series. I have one here that uses the Motorola name, it's called "Digital Stereo 10-band graphic equalizer using the DSP56001" seems to be named APR2/D. I seem to have a more recent one called "Implementing a 10-Band Stereo Equalizer on the DSP56311 EVM Board"; there's a section in it on how to setup your NT4.0 development environment - funny stuff.

[rfbrw]

Originally Posted by Yoshy

I look at some, I don't know if we're talking about the same ones. The ones I looked at targeted the whole 56k series. I have one here that uses the Motorola name, it's called "Digital Stereo 10-band graphic equalizer using the DSP56001" seems to be named APR2/D. I seem to have a more recent one called "Implementing a 10-Band Stereo Equalizer on the DSP56311 EVM Board"; there's a section in it on how to setup your NT4.0 development environment - funny stuff.

AN2110 and APR2 were the Freescale notes I was referring to along with another one for a Spectrum Analyser, though being for the 68HC16, it was of more use for its theory of operation.
AD also have tutorial that covers audio effects TN21065.

[tritosine]

I used to see useful tidbits here, notice "56k" :
http://www.dspguru.com/comp.dsp/tricks/alg/dc_block.htm