Stereo Tool

It's even worse than that...

DSP:

- install beta011
- reset all settings
- press bypass
- install beta013
- crash

Stand alone: http://www.stereotool.com/download/ster ... 20-014.exe
Winamp DSP: http://www.stereotool.com/download/dsp_ ... 20-014.exe
VST: http://www.stereotool.com/download/vst_ ... 20-014.dll

IMPORTANT: To get a good sound from the composite clipper:
1. Enable it It's an option under Advanced Clipper
2. Under Advanced Clipper -> CPU, set 'Strictness' at 11 or higher (higher is better; there's probably not much gain above 15 anymore though; 11 looks pretty good already so a bit lower values should still be ok).

Warning:
You will need a license update to use this! Otherwise the 'unregistered options in use' thingy will pop up, and you'll get messages through the music (every 4 hours).

DONE:
9. Update settings (default strictness values etc.) Jeroen Platenkamp's presets strictness can be lowered from 13 to 8 and it's still stricter than before
16. GUI crashes. This is new... Needs to be fixed.
17. "Performance: Not low freqs" and "Traditional bass/mids clipping" have a very similar effect, and I should probably remove one of them.

TODO:
15. Maybe make separate Strictness slider for Composite??? And also Loudness? And Highs Gap Protection? (Which might be less needed now since there are no highs gaps anymore - CPU effect is big!) --> No, is still needed.
18. Make sure Composite Clipping is not changed if you load a preset (part of FM settings)
19. Separate Composite Clipping settings into GUI modes (hide SSB in basic or simple mode etc.). Hide more from Loudness settings than from FM settings.
20. Update presets
21. Change version number
22. Release
23. Add warning if Composite is not enabled with FM. Clarify text (few dB more headroom, especially for highs, more loudness).
24. Fix clipping display.

REMOVED:
2. There was a complaint in the beginning of this thread that there were 'shrill' sounds heard due to the changes in highs clipping. That's still not resolved. --> Based on feedback I got, a loud shrill sound was played every few minutes in the early 7.11 beta's, but it doesn't happen anymore. Assuming this one to be fixed now.
8. Interesting observation: For Strictness settings below 7 (9 internally), the old clipping method works better than the new. So, it might be interesting to try to combine the two - that would again result in less steps. Not sure though what will happen to quality (I think the new clipping method is slightly better than the old one for that). --> Oddly, combining the 2 methods causes bigger spikes (overall the level seems slightly lower, as expected). Giving up on this one...
10. Since the old method works better for traditional clipping in low Strictness modes, is that also the case for composite clipping? --> Unlikely. And I implemented the new method because the old one didn't work well.

DONE IN PREVIOUS BETA'S:
1. Move or copy (same as Stokkemask filter) composite clipping and SSB settings to FM section.
3. Perform same performance optimizations in traditional clipper; remove 'Stronger clipping' slider once that's finished.
6. Replace DIV_PS by RCP_PS + MUL_PS in new clipper
4. Check bass and mid clipping issues reported by Bojcha.
5. Check clipping bug when clipping a 20 Hz bass tone and set bass clipping (in code) from traditional to MPX clipping. Why is the output level higher??
Ad. 4: Clipping is set to 'traditional' clipping for both bass and midbass. But levels are not adjusted to make room for the pilot and RDS signals. Also, potentially stereo bass will not be clipped optimally. However, if I want to use composite clipping for the (mid)bass as well, I need to fix a bug (currently multi-threading gives different output levels, I don't know yet why), and bass clipping strictness must be greatly increased, leading to a much higher CPU load - so this is probably not a very good idea. The simple solution is to adjust the clipping level to make room for the MPX signal. (Stereo pilot 9% + RDS 4.5% means that there's 13.5% headroom needed, so for default settings that means the clipping level must be multiplied by 86.5%.)
7. Check holes in center of bass -> might be better with new clipper --> Checked, little difference (some are better, some are worse).
11. Red output bars
12. SSB mode: Red output --> Not yet thoroughly tested, but should be fixed now. Added 0.01% headroom. Twice that for SSB mode. 1% for Hilbert mode (and that's still not enough - but you shouldn't use it anyway).
13. SSB mode: Check difference multicore/single core. --> Was pretty bad, now ok.
14. Fix behavior: When Composite Clipping enabled use normal clipping if FM or FM stereo coding is not enabled.

Why is it still needed? Is it still needed for traditional and composite, or just composite? Like you said, this is a large CPU load feature, especially on slower systems and if set to HQ.

Also, the stronger clipping slider is now grayed out at 6 and higher. You had mentioned doing this, but it sounded like you changed your mind. Is that how it is supposed to be now?

Finally, and I don't mind if it's put off for later, but could you comment on the idea of separate spike protection for band 1 and band 2 in the AGC?

@Brian:

1 - I thought it wouldn't be needed anymore (or at least less needed) in composite mode, but I've tested what happens when I remove it and it still has a big effect on the lows and mids.

2 - I wrote that earlier; I thought that combining the 2 methods would work better but it didn't. For lower Strictness settings, the old method (with Stronger Clipping) works better, for higher ones the new method gives better results - and it doesn't need this slider.

3 - Will look at that later, first finishing the current changes.

I got a PM from someone who did have the shrill highs issue with early beta's, but not anymore. Apparently in some cases a very loud shrill sound occurred every few minutes. So I'm assuming now that this issue is fixed - and will remove it from the TODO list.

I would mark it off the list. If it was a problem...it must have been a localized/system issue.

Nothing of the sort, here. Virtual sonic nirvana, here.

Stand alone: http://www.stereotool.com/download/ster ... 20-015.exe
Winamp DSP: http://www.stereotool.com/download/dsp_ ... 20-015.exe
VST: http://www.stereotool.com/download/vst_ ... 20-015.dll

IMPORTANT: To get a good sound from the composite clipper:
1. Enable it It's an option under Advanced Clipper

Warning:
You will need a license update to use this! Otherwise the 'unregistered options in use' thingy will pop up, and you'll get messages through the music (every 4 hours).

DONE:
15. Maybe make separate Strictness slider for Composite??? And also Loudness? And Highs Gap Protection? (Which might be less needed now since there are no highs gaps anymore - CPU effect is big!) --> No, is still needed.
18. Make sure Composite Clipping is not changed if you load a preset (part of FM settings)
19. Separate Composite Clipping settings into GUI modes (hide SSB in basic or simple mode etc.). Hide more from Loudness settings than from FM settings.
20. Update presets
21. Change version number
23. Add warning if Composite is not enabled with FM. Clarify text (few dB more headroom, especially for highs, more loudness).
24. Fix clipping display.

TODO:
22. Release
25. Add and update some more presets (Bojcha).
26. Make Hard Limit behavior for composite clipper less steep (causing less artifacts).
27. Increase default Composite clipping strictness to 15.
28. Fix Stokkemask clipper. --> Done, but has too much effect on highs and stereo separation. Needs to be calibrated, it's probably too strict now.

REMOVED:
2. There was a complaint in the beginning of this thread that there were 'shrill' sounds heard due to the changes in highs clipping. That's still not resolved. --> Based on feedback I got, a loud shrill sound was played every few minutes in the early 7.11 beta's, but it doesn't happen anymore. Assuming this one to be fixed now.
8. Interesting observation: For Strictness settings below 7 (9 internally), the old clipping method works better than the new. So, it might be interesting to try to combine the two - that would again result in less steps. Not sure though what will happen to quality (I think the new clipping method is slightly better than the old one for that). --> Oddly, combining the 2 methods causes bigger spikes (overall the level seems slightly lower, as expected). Giving up on this one...
10. Since the old method works better for traditional clipping in low Strictness modes, is that also the case for composite clipping? --> Unlikely. And I implemented the new method because the old one didn't work well.

DONE IN PREVIOUS BETA'S:
1. Move or copy (same as Stokkemask filter) composite clipping and SSB settings to FM section.
3. Perform same performance optimizations in traditional clipper; remove 'Stronger clipping' slider once that's finished.
6. Replace DIV_PS by RCP_PS + MUL_PS in new clipper
4. Check bass and mid clipping issues reported by Bojcha.
5. Check clipping bug when clipping a 20 Hz bass tone and set bass clipping (in code) from traditional to MPX clipping. Why is the output level higher??
Ad. 4: Clipping is set to 'traditional' clipping for both bass and midbass. But levels are not adjusted to make room for the pilot and RDS signals. Also, potentially stereo bass will not be clipped optimally. However, if I want to use composite clipping for the (mid)bass as well, I need to fix a bug (currently multi-threading gives different output levels, I don't know yet why), and bass clipping strictness must be greatly increased, leading to a much higher CPU load - so this is probably not a very good idea. The simple solution is to adjust the clipping level to make room for the MPX signal. (Stereo pilot 9% + RDS 4.5% means that there's 13.5% headroom needed, so for default settings that means the clipping level must be multiplied by 86.5%.)
7. Check holes in center of bass -> might be better with new clipper --> Checked, little difference (some are better, some are worse).
11. Red output bars
12. SSB mode: Red output --> Not yet thoroughly tested, but should be fixed now. Added 0.01% headroom. Twice that for SSB mode. 1% for Hilbert mode (and that's still not enough - but you shouldn't use it anyway).
13. SSB mode: Check difference multicore/single core. --> Was pretty bad, now ok.
14. Fix behavior: When Composite Clipping enabled use normal clipping if FM or FM stereo coding is not enabled.
9. Update settings (default strictness values etc.) Jeroen Platenkamp's presets strictness can be lowered from 13 to 8 and it's still stricter than before
16. GUI crashes. This is new... Needs to be fixed.
17. "Performance: Not low freqs" and "Traditional bass/mids clipping" have a very similar effect, and I should probably remove one of them.

I saw output level getting red again a few times. So seems that is not fixed yet.

ITU-R SM1268 is not working with composite clipper.

Ow! True! Will fix that now.

About red blinking: In which mode did it happen, and with what latency setting? (4096 non-SSB?)


Edit: Oioioi. It works now - but there's quite a big loss in stereo separation, and also some in output level (about 0.4 dB). Now more than ever it's getting important to precisely calibrate this Stokkemask clipper - until now the difference wasn't that big but in this new version it's getting bigger.

I'm wondering though if the Multipath filter cannot be abused to work as a Stokkemask clipper... Will run some tests.