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Fundamental frequnecy

Posted: Tue Mar 01, 2005 5:01 am
by overflow
Hello,

Question maybe little stupid, but anyway...It's well known thing that boosting fundamental frequencies of instruments is bad habit. But how can I define which frequency is fundamental? Let's say I have synth bass line. It's rather boomy. I know that I must cut fundamental frequency, but how can I determine which is fundamental?

thank you,
o.

Posted: Tue Mar 01, 2005 5:31 am
by HarBal
The fundamental frequency is the same as the frequency of the note being played.

For instance, I know the "A" just below middle C is usually tuned at 220Hz. The remainder of the notes in that octave are obtained by multiplying by the twealth root of 2 in succession, for each note in the chromatic scale. You can translate that octave to any other by multiplying by or dividing by the appropriate whole power of two.

There's probably a table of the frequencies on the net somewhere. Try googling for it if you don't want to calculate them yourself.

If by any chance, I got the frequency wrong above, I apologise. I'm an electrical engineer and not a musician.

Regards,


Paavo.

Posted: Tue Mar 01, 2005 6:09 am
by overflow
[quote="HarBal"]The fundamental frequency is the same as the frequency of the note being played. [/quote]

So dead simple... :oops:

thank you,
o.

Posted: Tue Mar 01, 2005 6:13 am
by har-bal
overflow wrote:
HarBal wrote:The fundamental frequency is the same as the frequency of the note being played.
So dead simple... :oops:

thank you,
o.
Overflow

Below is a link to a frequency calculator. You can input your fundamental/primary frequency and it will calculate the 1st , 2nd, 3rd, 4th, etc harmonic.

http://www.csgnetwork.com/harmonicscalc.html

Cheers

Earle

Posted: Tue Mar 01, 2005 6:16 am
by overflow
Thank you. Premium support!
BTW, found frequencies of notes here.


o.

Posted: Mon Jul 10, 2006 12:06 pm
by MERLIN
If say youve recorded bass guitar and the low E is really boomy, would you fix the 1st, 2nd, 3rd and 4th fundamental frequencies with eq adjustments, or just the main fundamental(1st)??

Thanks in advance guys :)

Posted: Tue Jul 11, 2006 5:32 am
by HarBal
You really have to look at the spectrum to the bass guitar part to really know what you should be cutting. If it is boomy then it is highly likely that the frequency responsible will be the strongest peak in the average spectrum.

Paavo.

Fundamental Frequency

Posted: Thu Jul 27, 2006 2:49 am
by Hitmaker
Hi ,

Paavo is on it , concerns individual notes , but the plot thickens when considering cuts from an instrument . Due to it's woods/construction/tuning it will have frequencies that resonate , and others that cancel ( worse if air cavities are involved ) . As a further complication , the key played ( the 8 of 12 tones ) may avoid/emphasise these colourations ... it's spectrum will be uneven ....
So we see , particularly in the yellow trace in HB , peaks .. which , if revealing a harmonic series , arise from the instrument , or it's interaction with the room ... worse if miked ....
The significance of these is that if excessive , particularly if narrow-band , they mask other frequencies ... and impart a ring-on after notes , and uneven scaling ... In general , a warm muddiness is created ( which may not be a bad thing .. if controlled )
This is easily visualised , and corrected with HB .... and the spotting of harmonic series made simple with the new Harmonic Cursor in 2.2 ...
If you want a very smooth , pure , but soft sound , massage your yellow trace to emphasis only one series ...
If we were to call the difference between peak and trough on your yellow trace a 'range' ... the less this is , the more your sound will get clean , go cold ... and generally sound compressed ... how you handle this depends on what you want for the sound ....
Not uncommonly in a bass , you'll find two sets of series , with fundamentals low and close ... this imparts a 'growl' to the sound ... which can be eliminated by reducing ONE of the series .. if desired ....
Another usefulness for understanding harmonic series is in simulating loudness ...
If you take the view that a sound which appears close to you , also appears loud , psychoacoustics can be used to this end ..
A sound's closeness is interpreted from the relationship of levels between it's fundamental , and early harmonics ... you want a gentle roll-off ( looking at the contour created by the tops of the peaks in the yellow trace ) over the first 3-4 overtones .. for a 'loud' sound ...
Such a sound will usually need less compression .. and retain better dynamics through your mix ...

Cheers ....

Posted: Thu Jul 27, 2006 6:14 am
by MERLIN
Thanks for that...Im still a bit confused but i think i understand.

I use the Hrmonic cursor over the problem peak area on the yellow line and only reduce 1 of its Harmonic fundementals...?? Is this right?


thanks guys :)

Fundamental Frequency

Posted: Thu Jul 27, 2006 8:21 am
by Hitmaker
Dude !!!!

The bit I didn't say was your fundamental(s) will be ( a) peak(s) , in the lower frequencies . There's likely to be more than one . If of a harmonic series , you'll see peaks near where the overtones are predicted by the Harmonic Cursor ... Have a play with it and all should become clear ..
As an example ... let's say we see a series of peaks at roughly 75 , 150 , 300 , 450 , and 600 Hz .... Of that series , your fundamental is 150 Hz ... 75 Hz is your first undertone at 1/2 x , 300 your second overtone at 2x ....
The number of series you have of roughly equal strength will determine the complexity of your sound ... a single series will be more sine wave like in sound nature ...
How you handle the relative levels of the overtones ( that's the harmonics ) within a series will dictate the percieved ( and usually electronic ) 'loudness' of your sound ...
A relatively lesser fundamental will give the sound of a small instrument ... A gentle level decay of your first few overtones will give 'closeness' ... Deeper valley/peaks a more resonant ( masking ) sound ....

Cheerz ....

Posted: Thu Jul 27, 2006 12:45 pm
by MERLIN
Thank buddy,

Im a bit more with it.....I understood that!!!! The first post was like a maths degree in a paragraph.....(im so not techniical)


Thanks :)

Posted: Sat Jul 29, 2006 1:37 am
by zumbido
Hitmaker,

The series of frequencies, in your example, starting at 150 Hz. (as you claim is the fundamental) creates a square wave. There would NOT be any 75 Hz. 'undertone' created by any of these frequencies (i.e., differential tone).

Now, if you were to START at 75 Hz., as the fundamental frequency, you have left out several of the overtones.

Following upto overtone number 'eight', the frequencies (in Hertz) would be: 75, 150, 225, 300, 375, 450, 525 and 600.

Of course, overtones go well beyond 'eight' and these values coincide with chord extensions. All the overtones, through the '9th' overtone, naturally produce a Dominant Ninth chord. All the overtones, through the '11th' overtone, naturally produce a Dominant Augmented Eleventh chord. And, all the overtones, through the '13th' overtone, naturally produce a Dominant Thirteenth chord.

Figuring overtone values is easy. Simply multiply the known fundamental frequency by the overtone number. For instance, if the fundamental frequency of an open 'E' string of a bass guitar is 41.203 Hz. (derived from equal temperment tuning, A = 440 Hz.) and you want to calculate the 3rd overtone - multiply 41.203 by 3. The frequency is 123.609 Hz. or a 'B'. This is approximately/near the same 'B', fourth fret on the G-string.

Remember, overtones are a 'pure Intonation' but we commonly use 'Equal Temperment' so this is why there are slight differences in the values of like-notes.

The volume relationship between the fundamental and its overtones are what gives an instrument it's "sound" - in addition to it's attack, decay and release. By the way, some instruments produce a 'louder' 2nd overtone than the fundamental.

Posted: Sat Jul 29, 2006 6:35 am
by MERLIN
Thanks zum,


As in the E note problem in our examples, would you still agree that only 1 of the fundementals needed to be lowered when there is too much eneregy on the E note.?




I tell you what....>I am very confused now about how to go about using the harmonic cursor>>>>>>>Most of my recordings/mixes seem to have too much bass eneregy around 110hz-250-hz(approx); Especially my bass guitar and guitars which i plug straight into the mixer to record (need to buy DI boxes).

Posted: Sat Jul 29, 2006 11:09 am
by zumbido
How you treat things with Har-Bal also depends on your recording/mixing environment.

Are you EQ'ing BEFORE recording? Perhaps your room is 'making' you add more in the 110-250 Hz. range. And then when you analyze with Har-Bal you see that you've added too much.

If you are getting this bump in 110-250 Hz. range I'd first suspect your room and second, this frequency range seems to be in the 'second' overtone range - which maybe 'the sound' of the instrument in question.

Posted: Sat Jul 29, 2006 12:38 pm
by MERLIN
Since i am not using mics to record and only di'ing the instruments, i think that it could be my crappy beringer mx160 mixer. Im gonna invest in a valve mixer soon, also gonna get some nice DI boxs. That should help the recordings! I normally use slight compression while tracking and dont use eq at this point. After the sounds are recorded in cubase sx3, i use voxengo plugs to inprove the recordings, since everything sounds weak and poor. I was thinking maybe its because im using a delta 44 soundcard. If i bought a motu, my recordings would sound better(i would like apachee but there soooo expensive.