Stereo Tool

>>New Version (0.6)<<

Experimental preset with 6dB/oct multiband crossovers

Smooth multiband EQ to stay relatively true to the source while maintaining some consistency. The goal is to maintain comfortable listening level with minimal sound quality degradation.

Almost finished...

v0.1: fix foundations

Common:
- slowed down AGC and enabled post-AGC compressor (new feature?)
- less agressive denoising

Normal version:
- Disabled features that are not needed for non-FM uses (Stronger Clipping, Bandpass Filter, Oversampled Clipping, Forcibly Remove DC, Hard Limiting) (Note: hard limiting was disabled to prevent stray peaks from the preemphasis from affecting the dynamics. the occational over/clipping (red volume bars) should not affect quality because the over/clipping is very light)

FM version:
- Enabled (non-advanced) Bass Protection.

Free version:
- Does not use any features that require registration
- Disabled features that are not needed for non-FM uses (Stronger Clipping, Bandpass Filter, Oversampled Clipping, Forcibly Remove DC, Hard Limiting)
- Preemphasized clipping set to 15us because the simple clipper isn't very good at handling preemphasis
- Lower limiting threshold on multiband band 8 and 9 to compensate for the reduced preemphasis

free.2 (updated free version, now sounds closer to the normal version):
- Disabled preemphasized clipping altogether. It increases the amount of HF content rather than reducing it so it was doing the opposite of what I was looking for. Multiband limiting does the job better.
- Increased clipping a bit to match the loudness of the normal version.
- Overall slightly cleaner but also slightly less punchy than the normal version.

v0.2: fix multiband

Normal version:
- No preemphasis
- A more comfortable EQ curve
- Made the 3band AGC act like a 1band AGC for more coherence but kept it in 3 band to get the 3band volume jump protection
- Slowed down multiband attack/release and increased multiband ratio (to do the 3band AGC's job)
- Less loud (less clipping. the "clipper sound" gets tiring after a long listen)

FM version:
- Basically the normal version with FM features activated and more singleband drive
- Higher band7-9 limiting threshold than normal version to compensate for preemphasis.
- Enabled advanced bass protection

Free version: Because of the reduced loudness and the absence of preemphasis. this version doesn't depend much on the advanced clipper so if you want a free version just disable the advanced clipper and everything will still sound the same.

Dear ST devs: Please don't remove the multiband volume burst protection. It's an amazing feature!

v0.3: keep up with changes

Common: more consistent and transparent
- Adjusted pretty much every dynamics processing stage to keep up with ST development
- Enabled BS-1770 Bass Correction in AGC and pre-clipper Singleband.
- Takes advantage of the new multiband volume burst protection. The new features allows me to...
- Slow down multiband considerably and eliminate pumping with slower music. Multiband pumping kills the reverbs on slow 80s ballads (ie. Madonna - Live to Tell)
- More agressive multiband gating. Because the bands all overlap a lot, setting the gating threshold just 1-3 dB below the multiband threshold doesn't do any harm as far as I can tell.
- Increased stereo seperation in the higher bands. Since the highs are almost never mixed centred it makes more sense to allow more seperation.
- Generally more bass, closer to the average of all music.
- Enabled azimuth correction. Don't know what it does but most serious presets have it so I guess it doesn't hurt to include it.

Normal & Free versions:
- Probably less loud than before (I can't tell because with the new beta all the old versions sound louder)
- Enabled hard-limiting anyway. Without preemphasis the stray peak problem is insignificant.
- Completely defeated deesser (MB volume burst protection is better)
- Advanced clipper or Simple clipper (free) makes practically no difference!

FM version:
- Same as normal version except for the FM features and advanced bass protection.

I tested with AC, dance and CHR and they were all pretty pleasant. I don't know if it works with Classical since I don't have the material but instrumentals and piano solos sound pretty good.

v0.4: more tuning
The volume burst protection and post-AGC single band was a little heavy-handed in the last version.

- Higher AGC target level
- Slower multiband release, longer release hold and even more agressive gating (1dB below compression threshold)
- Not relying on the post-AGC compressor to control bursts anymore.
- Tuned burst protection against more tracks. Unfortunately it's almost impossible to protect against volume bursts consistently without significantly disturbing the dynamics on some tracks so I chose not to completely eliminate all volume bursts.
- Other small tweaks here and there that I can't remember.

I'm not going to make FM versions anymore. Since the only difference between FM and non-FM is that the FM version has FM oriented features and more pre-clip singleband drive, a separate FM version is unnecessary.

Free version can be created by disabling the advanced clipper. It will be 1dB quieter because the simple clipper is not as good at preserving punch as the advanced clipper.

v0.5: lookahead
- mostly the same as v0.4 but with the new multiband lookahead
- slightly higher burst protection thresholds (the addition of lookahead should make this safe)
- tweaked AGC remove-remaining-peaks.

It's pretty much done for now. Updates will only be for new beta versions.

v0.6: no coupling
- Disabled band coupling. It's just not needed with 6db/oct
- Reduced clipper strictness. 0dBFS isn't reached that often so low strictness is ok.
- A little more bass
- Less agressive burst protection