Spectrum analyzer display “only”

[pshannon]

Hello Everyone,
Does anyone know if you can just capture the Band to only display the level? I do not want to alter the audio in anyway. I know about using the audio equalizer biquad filter coefficients for low and high bands to actually filter. That does work for displaying levels, however at a cost and you would join them together to create a multiband eq. However, this eats up a ton of CPU when you hit more than 16 bands. My summary to the question, can you capture the band high & low values you select and display the levels without using the heavy cpu biquad filter coefficients? I know I might be stabbing in the dark, so I thought I would ask a question that I was hoping that there is a simpler way. Thanks to any responses.
E.Q. Display 100hz-200hz, 201-300hz etc.

[pshannon]

An update to this question: Does the "mono to Graph" object inside the scope object capture everything I need? If I narrow down the array to high and low values and display that together, attach it to a meter, will that solve this and find what I am looking for? Please bare with me, it has been almost 3 years since I used the FS product and I forgot how much I loved this and how often you lose track of time while playing with it.

[tulamide]

I hope somebody with actual dsp skills will chime in.

I'm just wondering about the mentioning of the "mono to graph" prim. It just delivers the amplitude values in time domain, while what you're looking for is a specific band in the frequency domain. Wouldn't you need to convert this band back to time domain, to get the levels?

[pshannon]

I hope somebody with actual dsp skills will chime in.

I'm just wondering about the mentioning of the "mono to graph" prim. It just delivers the amplitude values in time domain, while what you're looking for is a specific band in the frequency domain. Wouldn't you need to convert this band back to time domain, to get the levels?

The "mono to graph" might be only displaying amp levels, I wasn't 100% sure and this was a 5 min look at the scope stabbing in the dark There is not a ton of info I found for that prem and I am unfamiliar with it. I am hoping for an equation that can root out the band levels between high and low with lower cpu. It can even be good enough? If it was to display in real time, it would be hard to know if it was 100% accurate vs 10% off but fast. If I was going to change the audio, which I already know how to do that, then I would want more accuracy of course. If someone just tells me, you have to just use the biquads to do this, then I will accept it. I was hoping I am wrong. Thanks

[wlangfor@uoguelph.ca]

Use MV's ZDF filter. Look for the post transfer function. I posted it a long time ago. Marting Vicanek provided me with one which had his own ZDF filters. Use the BP1 to achieve what you desire and then use that for your test of db.

It's the fastest test filter I've used. I've also used fft, previously un-successfully but now I've gotten it to work. They're about evenly matched CPU wise. I was able to come up with something cooler with the ZDF, but could do more with the FFT version but have'nt had the time to work on it more. GL.

[pshannon]

I found the info you were talking about and at a glance, I think this will solve some or all of my requirements. The funny thing is, I searched the blogs earlier before I posted, not sure why I couldn't locate this exact questions that were previous proposed from you working on the same things. Thanks for your input.

[wlangfor@uoguelph.ca]

I found the info you were talking about and at a glance, I think this will solve some or all of my requirements. The funny thing is, I searched the blogs earlier before I posted, not sure why I couldn't locate this exact questions that were previous proposed from you working on the same things. Thanks for your input.

no problem.