Stereo Tool

A few weeks ago Bojcha reported the following issue: Bass sounds better without 'Advanced Bass Distortion Protection' enabled.

I found a bug in the code (or actually a few bugs) and I've fixed those. The result is the version linked below.

One warning though: The highs are affected by the louder bass. I discovered that there's a bug in the highs filtering (in version 6.20 and above), that's probably hurting the quality of the highs (and at least it makes them softer than they should be) - intermodulation distortion is happening TWICE, which is of course very bad. If I fix this bug though, the lows and mids are ducking again when there are loud highs. I think I know how to fix it (clip the amount of ducking), but it's not implemented yet.

In this version, in my measurements I saw an increase of 1.4 dB in the bass region (biggest boost is around 100-150 Hz), and a drop of 0.2 dB above 3700 Hz.

EDIT: Oops, I see that I've compiled a version with drops instead of lower highs! Well, the next version will have a configurable maximum drop level.

Stand alone: http://www.stereotool.com/download/ster ... 31-001.exe
DSP: http://www.stereotool.com/download/dsp_ ... 31-001.exe
VST: http://www.stereotool.com/download/vst_ ... 31-001.dll

Configurable highs level added (see bottom right of Loudness panel). At 0%, it behaves the same as before (which means you'll loose some highs due to the louder bass). At around 6% the amount of highs is roughly identical to that of version 6.30. At higher values you'll get more highs, but the other frequencies will drop a bit. This may sound better though (haven't tested thoughoughly yet).

Stand alone: http://www.stereotool.com/download/ster ... 31-002.exe
DSP: http://www.stereotool.com/download/dsp_ ... 31-002.exe
VST: http://www.stereotool.com/download/vst_ ... 31-002.dll

Whoa, what a quick beta... I hope the presets get updated this time.

Although this beta sounds very clean I can't honestly hear any difference between "Highs Priority" slider set at 0% or 100% Maybe my hearing is going?

Mine too...

@Hans - Is this a FM broadcasting and/or pre-emphasis and/or oversampling-related issue?

The effect is definitely a lot bigger with pre-emphasis. Even then the effect is small though.

Athl0n: Do you think that it sounds cleaner than 6.30? Because I also received a complaint about 'weird sounds' that were present (haven't heard them myself yet), and I know now that I did some things wrong in this new version - I'll have to fix those.

Hi Hans,

improved high frequency is remarkable, but also on the low frequencies
but I feel in some cases strange "popping"
is it possible? (such as digital clicks)

Those may be the "weird sounds" that someone (Bojcha) mentioned - not sure though.

I'l currently redesigning it again because this new design also has some weird effects. Will probably be finished tomorrow, maybe that will fix this.

ooookkk !!!

THX

Ok, I'm apparently missing something obvious in the bass clipping (and fixing that would *really* improve the quality). Still thinking......