amplify at frequencys

[Robert J. H.]

with the equalizer but which does not seem to work with single frequencies

Does any filter really work with single frequencies, as opposed to slightly affecting neighbouring frequencies?


Gale

Good point Gale.

It is the same problem as with a perfect lowpass filter that stops at exact 300 Hz and rejects all frequencies above.
The steeper the slope, the more begins the frequency in question to resonate.
However, this is essentially what the user wants.
The function that emphases frequencies in regular intervals is called "Comb".
Example: Generate a Chirp tone, not too loud, and put this code into the Nyquist Prompt (Effect menu):

Code: Select all

(multichan-expand 'comb; Alternatively: 'alpass 
   s; input sound
   0.5; Decay time (less for subtle effect)
   100); Frequency in Hz 

You can of course change the decay time and the frequency and also the function itself, alpass is not so metallic/harsh as comb.
The example resonates at 100, 200, 300 etc Hz.

Reduce the decay time until your satisfied (applied to music, for example).

[andreas84]

thanks gale it worked so far

[andreas84]

WOW Robert j.h. That is really what i looked for and i have applied it it sounds great, bit like an echo but really awesome Thankyou!!!

[Robert J. H.]

WOW Robert j.h. That is really what i looked for and i have applied it it sounds great, bit like an echo but really awesome Thankyou!!!

You mean Reverb? That's no surprise since Reverberation is fashioned this way.
You could of course do It in to steps:
- use the code (with less decay or delay as I've wrongly named it)
- reverse the sound (effect menu)
- use the code again
- Reverse the sound back.
This centralizes the resonance over the tone.

[andreas84]

Well i made one effect it was pretty neat, the next i would want to try is to try to apply it to the Solfeggio frequencies the way i have calculated them.


It is: Basefrequency is 84.5 and every frequency above would be: 110.5 more.

so: 195 305.5 416 and so on

[Robert J. H.]

Well i made one effect it was pretty neat, the next i would want to try is to try to apply it to the Solfeggio frequencies the way i have calculated them.


It is: Basefrequency is 84.5 and every frequency above would be: 110.5 more.

so: 195 305.5 416 and so on

I feared as much. The problem is that a comb filter's interval is equal to its fundamental frequency.
Thus, You had to shift the whole spectrum by 25 Hz to 110.5, apply the comb filter and shift it down again to 84.5 Hz.
That's hard to do because normal pitch shifting or resampling increases the frequencies by a percentage and not a constant value.

Another possibility is to boost the frequencies one by one. There's also the question how broad the peaks should be. Musically seen, those peaks are measured with a Q factor. This means that the peaks have always the same broadness in terms of pitches.
As an example, The tone A is at 440 Hz and the q is such chosen that the width is one quint (about 330 Hz). This width doubles in each octave. In the beginning it will fit between 0 and 880 Hz but not at 4400 Hz, between 3960 and 4840 Hz because it is now 3300 Hz broad.
Thus, the Q factor must increase with each step. This increases the oscillation or resonance for high frequencies and might not sound very nice. That's just a preliminary remark, provided there are no calculation rules for the width in your scheme already.