Audio filter amplifyers

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Anonymous
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        Hearing loss. Can I use the PSOC 1 to create a profile for my hearing loss   
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Bob_Marlowe
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There are probably much better dedicated DSPs for audio-filtering than a PSoC1. The filter is not able to adapt frequency enhancement on several different freequencies as in hearing-aid devices.

   

Supressing or enhancing a single frequency band as in a bandpass or in a bandstop can be done easily in PSoC1 with a PGA and a filter.

   

 

   

Bob

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ETRO_SSN583
Level 9
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Years ago the peformance level of simple BP and BR filters was

   

considered adequate at the 2'ond to 4'th order level. But if your

   

hearing loss complex, not a simple smooth peak or reduction

   

in response, those methods no longer considered adequate.

   

 

   

Additionally you have to deal with switching noise in switch cap filters,

   

which PSOC is, unless you use its PGA to synthesize continuous time

   

filters. Not difficult to do, a simple LP filter gets rid of most of the noise

   

due to oversampling nature of SC filters. But then you also have the

   

same problem on the D/A side of a digitial filter.

   

 

   

PSOC 1 can do digital filtering, it has an onboard multiplier, and you can

   

implement IIR, or FIR, but not as wide a range of response as PSOC

   

3/5.

   

 

   

    

   

          

   

http://www.cypress.com/?rID=2813     AN2099

   

 

   

 

   

Regards, Dana.

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Anonymous
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        Thanks for the feedback. What DSP IC do you think would be a fast learning rate. I can't see myself spending $4500 for hearing aids.   
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ETRO_SSN583
Level 9
Level 9
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You could consider PSOC 3 or 5LP, as they both have DFB. As well as

   

basic signal conditioning like OpAmp, PGA. DFB also has assembler permitting

   

you to create custom filter.

   

 

   

One of your challenges will be size, package will be one of the issues.

   

 

   

Regards, Dana.

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Anonymous
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        Thanks for the response. PSOC has the filter wizard that I like using for audio. If I used the filter block in PSOC 5 where would I find the software routines for the custom filters?   
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Anonymous
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        I am not concerned about size. I was thinking of a package size like an MP3 player.   
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ETRO_SSN583
Level 9
Level 9
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Custom filters are your ground up design by using the basic HW in the

   

DFB. There are library sized collections of books on DSP filtering,

   

many vendors have tools to determine pole/zero locations, show response

   

you will get, just google "digital filter design tool".

   

 

   

Regards, Dana.

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Anonymous
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        I purchased the EVAL-ADAU1452MINIZ. The SDK was $225. It comes with GUI software. I still think the PSOC 5LP is the way to go.   
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