DSP systems, software, hardware. https://clk.works/ Audio Builders Workshop. http://audiobuildersworkshop.com/

(apologies to @artmez, when I started writing this there were no other replies and it was 2 days old.  We must have both posted at the same time)I was hoping one...

Re: Can lossless audio be transfered via bluetooth?

Reply posted 4 months ago (06/02/2021)
Hi An,No problem.  I wrote that a bit tongue-in-cheek, i.e. gave you answers of No, Maybe, and Yes, all perfectly correct in response to your question as stated.I...

Re: Can lossless audio be transfered via bluetooth?

Reply posted 4 months ago (06/01/2021)
Sure, if your audio (data) is at a low enough sample rate, the answer is a resounding yes.  (8 bit audio at 8 kHz - no problem)...but that's probably not the answer...

Re: Creating your own dev board

Reply posted 11 months ago (11/03/2020)
I'll second all of the excellent comments that have been made, and I'll throw out a couple of suggestions too.I think for someone in your position is the journey...

Re: Get RMS value from Pulse Density Modulated signal

Reply posted 1 year ago (03/30/2020)
Ah, got it.  Barring some clever way to fold that table due to some symmetries of some sort (just a WAG that there might be some) really then it's a tradeoff between...

Re: Get RMS value from Pulse Density Modulated signal

Reply posted 1 year ago (03/30/2020)
Not to drag this out, but why are you using a 16 bit table?  8 bits drops the rate to to a very manageable value and you could take it down to 500 Hz or so and...

Re: Get RMS value from Pulse Density Modulated signal

Reply posted 1 year ago (03/29/2020)
You can't manipulate PDM (or PWM) data mathematically (AFAIK...maybe someone else knows).  In the end it's nothing more than a "value" of some signal and it's the...

Re: Get RMS value from Pulse Density Modulated signal

Reply posted 1 year ago (03/28/2020)
Thanks for the detailed explanation.  Did you look at this older post?https://www.dsprelated.com/thread/6809/mcu-signal-...in addition to the ST app note referenced...

Re: Get RMS value from Pulse Density Modulated signal

Reply posted 1 year ago (03/27/2020)
I think I made an oops from reading your original question. It's not the filter output that's at 1 MHz, that's the PDM rate? What is the rate out of the filter/downsampler...

Re: Get RMS value from Pulse Density Modulated signal

Reply posted 1 year ago (03/27/2020)
What bandwidth are you looking across for the RMS measurements?  If this is AC (mains) power then unless it's some exceptional condition you're chasing probably...

Re: Get RMS value from Pulse Density Modulated signal

Reply posted 1 year ago (03/27/2020)
Not sure what your sample rate and bandwidth are, but the long hanging fruit on this would be to filter and decimate to reduce the amount of data.

Re: FFT stitching

Reply posted 2 years ago (03/17/2020)
I read this as sounding like extending the "trick" of reducing FFT complexity by 2 when the input sequence is real (i.e complex ={0}) since you know the output...

Re: How to obtain impulse response of a room acoustics

Reply posted 2 years ago (01/22/2020)
Not directly answering your question in terms of algorithms, but in terms of a really good measurement tool and a fairly extensive writeup check out REW (Room Eq...

Re: What is the cost of a typical MSEE degree?

Reply posted 2 years ago (12/17/2019)
Northeastern in Boston (where I have one child in an undergrad eng. program ) is $52K for tuition (only) for a MSEE. A room in a shared apartment is another $12K+...

Re: damping filter - finite stationary error

Reply posted 2 years ago (11/26/2019)
Total W.A.G. here since there's no details as to what is meant by damping filter, nor code, etc, but looking at that plot it looks like maybe you have 8 bit math...
Can you tell us what problem you're trying to solve?  Maybe a FFT/IFFT isn't the right approach.  (here comes the 20 questions) If I understand it the data is...

Re: FFT Interpolation

Reply posted 2 years ago (07/27/2019)
For me, whenever I got myself confused on this, I fall back on "calling one side of the transform time and the other frequency is just a convention (yeah, I mighty...

Re: Window Impulse Response

Reply posted 2 years ago (06/25/2019)
There's a couple of things in what you state that don't sound quite right to me, but I've also been away long enough from the details that I'm probably wrong about...

Re: Todo List: Improvements to the Related Sites

Reply posted 2 years ago (05/02/2019)
The responsive design fixes would be good - I try and avoid serious reading on my phone but sometimes while waiting for something it's how I get caught up.  I'm...

Re: DSP Dev Kits for learning

Reply posted 3 years ago (03/26/2019)
If you don't have need for extreme speed in what you want to do (you used the word 'basic' so I assume this is the case)  I would suggest one of the ARM M7 or new...

Re: USB to I2S adapter for audio transceiver

Reply posted 3 years ago (01/31/2019)
Sounds like one of the XMOS eval boards could work for what you want to do.

Re: fixing sample rate error/mismatch

Reply posted 3 years ago (01/15/2019)
Fred's response is spot-on, I'll throw in some additional things I've seen that might be a problem in some cases.  If one (or more) of the sources are coming over...

Re: Overlap-add with window

Reply posted 3 years ago (01/10/2019)
Hi Rick,Sorry I should have been clear when I made that link/reference; you are correct about what was on that page but I should have said  "start with this page...

Re: Overlap-add with window

Reply posted 3 years ago (01/10/2019)
Hi Rick,I fell in to that "trap" recently; I may have missed something fundamental but I played around with a couple of Matlab scripts to investigate. The short...

Re: Overlap-add with window

Reply posted 3 years ago (01/10/2019)
Hi @ctlee,I usually find myself using a ramp as the fast + to - transition can provide a good marker for measuring time, i.e. if I want to get the exact frequency...

Re: Overlap-add with window

Reply posted 3 years ago (01/09/2019)
I should have added that I find using a ramp waveform is extremely helpful to find that occasional sample where you're "off by 1" and then debug the code - if you...

Re: Overlap-add with window

Reply posted 3 years ago (01/09/2019)
Having just spent the last month working on a project that used FFT/IFFT for a slightly different purpose with overlap/add, I found Julius Smith's book extremely...

Re: Need help - Pink noise analyzer

Reply posted 3 years ago (06/04/2018)
Darn let me correct myself before I confuse things further...pink noise has equal energy per octave, which means the power drops off at -3dB/octave.

Re: Need help - Pink noise analyzer

Reply posted 3 years ago (06/04/2018)
I think you meant -3dB/octave and -10 dB/decade?

Re: Need help - Pink noise analyzer

Reply posted 3 years ago (06/04/2018)
If the red in your plot is the FFT results then that's not the FFT of typical pink noise.  BTW for any given FFT there is going to be significant variation (it's...
What you're describing sounds like the scheme cable TV used in the 80s to 'block' movie and porn channels. The (analog) waveform was 'distorted' (sync pulse messed...

Re: DSP diagramming software?

Reply posted 3 years ago (04/16/2018)
Surprised nobody mentioned Inkscape. https://inkscape.org/en/  For a long time it was a package with potential but it's now to the point where it can handle what...

Re: Problem of Input voltage for LM4862 audio amplifier

Reply posted 4 years ago (11/21/2017)
Others have addressed why C1 has to be there. I would like to add my $0.02 about the requirement that one side of the speaker must be grounded. If this is the case...

Re: Subharmonic distortion?

Reply posted 4 years ago (04/28/2017)
Couple of questions/ideas:What happens when you change the level of the signal generator? Does the mystery component change level too?What happens when you change...

Re: Downsampling from 2.0 MHz to 192kHz

Reply posted 5 years ago (10/26/2016)
At the risk of being redundant with the other answers, your original question basically asked how to (in an equivalent analog domain) low pass filter a 1 MHz bandwidth...

Re: Processing block size and matched filtering

Reply posted 5 years ago (06/16/2016)
Others have kind of asked the same questions, but maybe differently than I would ask it before trying to figure out how to solve this...so here's my $0.02Noise:...

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