I have been involved in electronics design for over 45 years, 40 of those years as a career. My specialisation is currently digital signal processing, which has been my main activity for the past 15 years.

Re: Interpolated FIR filter group delay

Reply posted 3 years ago (05/19/2018)
As regards the IFIR, it will perform no better than a conventional FIR in terms of group delay, but it could consume less DSP cycles - that is really its only advantage....
I don't think any of the punters will notice a LPF at 20kHz. If you desire a less bright sound, then may I suggest a more gentle shelving filter which attenuates...
So it sounds like you can have a DSP channel dedicated to each zone, which will allow you to EQ each zone independently, which has to be better than having no DSP...
It depends what you want the DSP to do to the resulting sound. If you are simply applying some Equalisation, then the *change* in EQ will be the same if there is...

Re: overlapping acquired audio data

Reply posted 4 years ago (02/22/2018)
Yes, if the changes are sufficiently abrupt to warrant it, you could for example use triangular windows with a 50% overlap (to keep it simple). You would then of...

Re: Artifacts in Time Varying IIR Filters

Reply posted 4 years ago (01/04/2018)
You might like to refer to the AES paper "The Time-Varying Bilinear Transform" by Able & Berners.Probbie

Re: FIR Amplitude

Reply posted 4 years ago (12/12/2017)
Yes, multiplying your coefficients by a factor will increase the gain by this factor, but I would recommend that you try to understand what is happening so you can...

Re: IIR filters

Reply posted 4 years ago (11/29/2017)
An IIR filter is very useful for replicating the response of an analogue filter, using very little DSP resource and imposing very little latency. One example...

Re: AGC on FPGA

Reply posted 4 years ago (11/14/2017)
Hello,You should integrate your data otherwise, if the algorithm acts 'instantaneously', you will have built a clipper rather than an AGC. The integrator would be...

Re: Typical filter orders for DSPs

Reply posted 4 years ago (08/04/2017)
IIRs would usually be anything between second order and maybe 16th order. Any more than that and you would probably be better off considering FIR. It depends on...

Re: Writing DSP routines in C or assembly?

Reply posted 4 years ago (08/01/2017)
It really depends on how much processing you need to squeeze in. You will get very dramatic improvements in efficiency if you write in assembler. The compiler will...

Re: Filtering of amplitude spectrum

Reply posted 4 years ago (04/21/2017)
In that case, as has been suggested, you need to apply a moving average filter to the data points you are collecting (assuming that the source of the curve you have...

Re: Multiband dynamic processing

Reply posted 5 years ago (04/18/2017)
If you use a parallel filter bank, the biggest issue will be the phase relationship between the bands when you sum them together again. If you use linear phase FIR...

Re: PAPR (peak to average power ratio)

Reply posted 5 years ago (04/13/2017)
It's largely a cost thing. Very high power amplifiers are very expensive partly because of the expensive high-power parts, and partly because at the very highest...

Re: Deriving FIR coefficients for a higher sample rate

Reply posted 5 years ago (04/12/2017)
Hi KazGood suggestion - seems to work. I have to finesse the transition from the last bin to the value used in padding in order to avoid frequency domain ripple.Many...

Re: Deriving FIR coefficients for a higher sample rate

Reply posted 5 years ago (04/12/2017)
Hi RickThat works for me! I didn't bother with trying to do it with fft/dft in the end since this is an offline operation. Just bought myself a copy of your book..Have...

Re: Deriving FIR coefficients for a higher sample rate

Reply posted 5 years ago (04/10/2017)
Hi RickThat looks *really* interesting. I am currently working through it to see if I can use fft/ifft. Any pointers would be much appreciated. (BTW Looks like...

Re: Deriving FIR coefficients for a higher sample rate

Reply posted 5 years ago (04/10/2017)
Hi DavidReally appreciate the suggestion. I believe what you are suggesting is a more efficient implementation of interpolation. Efficiency isn't a big requirement...

Re: Deriving FIR coefficients for a higher sample rate

Reply posted 5 years ago (04/07/2017)
Hi KazReally appreciate the suggestion. That gives me alternate 'holes' in the magnitude response of the new FIR. I can't do simple linear interpolation on the...
Hi folksDoes anyone have any tips on how I might transform a set of FIR coefficients from one sample rate to another at an integer multiple (2 in this case)?Since...

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