Topic: Bass roll-off in audacity

[jadg2]

Hello,

I'm trying to mimic the bass-roll off I would get in from a CSB battery box bass filter running into a sony HiMD.  (Think it works out as cutting off below 120Hz)  I was at a concert last night by some loud rock bands and had to run line-in to prevent the md pre-amp from overloading by recording at too low levels, so subsequently the bass is now very boomy.  Here's a sample of the show:

   http://rapidshare.de/files/34263618/torche.mp3.html

I only have audacity available to me, unless someone else can recommend some other free mastering/editing software.  Also I have sonicstage mastering studio, but am not familiar with that progam.  Any help appreciated, if you can make a nice sounding sample, then please, let me know how it's done.  Apologies if this has been asked before, couldn't find a thread to help. 

J

[Roving Sign]

Effects > High Pass Filter

...Set Cutoff Frequency to 120

If your levels were too low you might want to use the Amplify effect first - Select All > Effects > Amplify

...it will automatically dectect how much gain to add...just accept the default value.

[jadg2]

That's super, cheers.  Not too happy with the results with that filter though!  Maybe it's the recording... 

No seriously, I've been toying with this sonicstage mastering studio as it has better equalisation tool.  What's a 'good' amount to roll bass off? Or is that entirely subjective...

I'm trying a steep reduction below 120dHz & a lesser gradient to about 300Hz.  Is that reasonable to reduce the painful bass?  Any specific tips appreciated, apologies for vague and impossible questions 

[Roving Sign]

Try beefing up the midrange...that might bring the listenable part ahead of the bass...

[dorrcoq]

Try beefing up the midrange...that might bring the listenable part ahead of the bass...

OK, I have to ask - how do you do that?

[jadg2]

Try beefing up the midrange...that might bring the listenable part ahead of the bass...

OK, I have to ask - how do you do that?

Ditto for that.  So this sonic stage mastering program is a bit more programming, and have found a proper equaliser.  What's a good freq too filter off the bass from, to retain as much of the sound as possible whilst still making it listenable?  Think I read elsewhere on the board around 300Hz to eliminate.  Here's an image to show you what I mean,

[Brian Skalinder]

What's a good freq too filter off the bass from, to retain as much of the sound as possible whilst still making it listenable?  Think I read elsewhere on the board around 300Hz to eliminate.

Two factors will impact your HPF (high pass filter, or bass roll-off):  frequency and slope.  The frequency represents the point at which one one starts to apply the filter;  the filter is applied to frequencies below this point.  The slope is how quickly one wishes to filter below the frequency target, i.e. how swiftly to roll off the bass, typically noted in dB / octave.  Common values are -12 dB and -6 dB, but that doesn't mean you have to use those specific values.  (-12 dB / octave will remove bass more quickly as you move below the frequency target, while -6 dB / octave will remove bass more slowly.)

300 Hz sounds awfully to high to me, but the actual value will depend on your recording, ears, playback, etc.  Try starting at 80 Hz with a -6 dB /octave slope.  I'd then try 80 Hz with a -12 dB slope.  See how it sounds.  If it doesn't remove enough low end, move the frequency up (to say, 100 Hz) and try both -6 and -12 dB slopes again.  Or if it removes too much low end, drop the frequency to, say, 60 Hz.  Experiment until you find a frequency and slope appealing to your ears.

[jadg2]

Many thanks.  Did I mention these bands were detuned and guitar heavy?    
Hence the severe slope, anything above that really keeps too much of a painful low end in, but anyway, thanks again for the advice & apologies if this was covered in an faq.