This simple tool adjusts the volume and EQ (bass-treble balance) of a .wav file.
It's mostly just a silly experiment, but it can be a useful reference point when mastering or just post-processing tracks.
Don't use it on short sounds or single instruments, as it usually work better full mixdowns.
Download Auto EQ drop and place it in a folder somewhere.
More "styles" can be unlocked by enabling the additional sections in the .ini file.
Download AutoEQ.exe if you prefer the command line then place this in the path, for example in C:\Windows\
Download AutoEQ for linux, unpack and place it in the path, for example /usr/local/bin or /usr/bin.
You might have to do a
sudo chmod a+x /usr/local/bin/autoeq
to make it work.
Then simply run "autoeq" to see if it's installed.
Windows & Linux
The easiest way to use it is like this:
autoeq "input.wav" "output.wav"
A bit of explanation
The AutoEQ runs through the .wav file twice.
First it reads the whole .wav file and finds out what the frequency curve is.
Then it inverts that curve, so that anything that's too loud will be attenuated, and things that are too low will get boosted.
This curve then gets smoothed a bit to avoid unnatural results.
Finally, during the 2nd pass through the audio file, this fixed EQ curve is then applied to the output .wav file.
Command line parameters
Options that can be used for the command line version or in the AutoEqDrop.ini file.
value between -80 and 40 dB, default is 0 dB
Output volume gain.
value between -100 and 100%, default is 15%
Global bass/treble frequency tilt. Zero gives brown noise, 100 is white noise.
value between 0 and 20000 Hz, default is 50 Hz
Highpass filter frequency. Subsonic (very low) frequencies are not just inaudible, they also cause a lot of nasty problems for your speakers, your amp, and would even made the output signal quite loud - mostly because of stuff noone can hear. So highpassing that away is a good idea. The filter isn't very steep, so even at the default setting there's still audio at 20 Hz.
value between 0 and 100%, default is 40%
Amount of smoothing of the equalization curve. Applying a very sharp and irregular EQ curve causes some weird artifacts around transients (sudden peaks like drums), so by default we smooth the curve. More smoothing causes less severe changes to the sound character, whereas less smoothing will make the effect more aggressive.
value between 8 and 24 bits, default is 0 bits
Set number of bits in the output file. Usually AutoEQ will output a stereo .wav file with the same bit depth as the input file, but you can override this if you like. Valid choices are: 8, 16 and 24.
Causes 8-bit input to produce 16-bit output files, and 16-bit files will be written as 24-bit. 24-bit files will remain 24-bit.
With this setting enabled, AutoEQ will scan for the loudest peaks in each frequency area and build a curve based on only the peaks. Cannot be used if -average is used.
With this setting enabled, AutoEQ will build an EQ curve based on the average amount of audio within each frequency area. Cannot be used if -peak is used.
value between 0 and 100%, default is 0%
Custom shape: Add mid emphasis. If you set this to zero, the output will have a completely straight frequency responce.
A few examples
autoeq "input.wav" "output.wav"
Old-school sound, might work better for classical music:
AutoEQ has been re-written from scratch, and is now a 64-bit application that should load both 8, 16 and 24 bit .wav files,
stereo as well as mono, 32-96 kHz. 192 kHz is still untested. The meta data in the source .wav file will be retained.