Stereo Tool

I have one simple and small cosmetic request for ST, Actually for ST input VU meter (and maybe for output)

When input reaches audio over 0dB (or even -0,5) then meter flash whole in, let's say red color, which mean that input is clipping.

Hi Bojcha,

I cannot detect that _input_ gets higher than 0dB (I can see precisely 0dB, but that doesn't necessarily mean distortion - although if you're using line in it probably does (but not if it's coming through VAC, ...). For _output_ this is possible (actually I was thinking about adding something like this for output this morning )

I had an old cassette deck where the level meters also displayed the maximum level of the last few seconds, maybe that would be a good idea for the input meters.


Edit: On the other hand, even for input if the max level is reached that can mean that there's distortion, for example if an MP3 is recorded too loud etc. So I'm going to make it flash also (if you're playing things that cannot distort you can easily ignore it).


Edit #2: LOL... I just found out that the output is actually slightly too loud (up to about 0.04%). That's because Hard Limit cannot work perfectly with NO look-ahead space at some points in the processing. So I'm going to lower the output level by about 0.07% (to be on the safe side).

heh...
you mean "peek hold"



That's was just cosmetic proposal ... we can live without that...
i am always use input level at half meter (standalone) and for ST dsp plugin "winamp preamp" at -5.5dB
Anyway, easily in standalone someone can put more input then needed.

Building update now.

Changes:
- FM Calibrate should work again (I made a mistake in the memory management, again...)
- Highpass filter: Non-linear version now works on all frequencies 5-200 Hz
- Bars turn red when sound is too loud, for both input and output

Tomorrow I'm going to add the loading and saving of the new settings
I'm also running the stand alone version here to try to reproduce the stopping of the Stereo Boost output display (since this morning) - so far with no success.

Uploaded as BETA3A.

Now question from erlier. Why output bar is red ?
In v4.22 if Post-Amp is at -0.08dB never crosses that few pixels in vu-meter.

Because Hard limit ?

What do you mean? If Post Amp is set to -0.08 those few pixels still don't get filled. And now with the slightly lower output volume (-0.0006 dB or so) with Post Amp set to 0 dB it should never turn red.

In v4.22 the Hard Limit filter was more precise, because it could look ahead. In the new versions, it cannot always look ahead, hence small (0.04%, or 0.0003 dB) spikes may occur. By slightly lowering the output volume (now hardcoded in Stereo Tool), this is avoided.


Or do you get a red output bar? (If so, what are your settings?)

ST Standalone - Normal Output
If the input more then 48kHz, Output flashes red, sometimes even at postamp -0.5dB.
At 48kHz all looks good!


FM output is Ok, but when you set FM overdrive more then 101%, output bar is red again.

Woops - that's a bug - not in the display, but in the processing itself! Will check!

Edit: Found it!
Hard Limit works at 44.1/48 kHz if FM output is disabled (but then the actual output is 4* that, causing extra peaks in the signal -> overshoots).
If FM output is enabled, Hard Limit works at 4* the frequency again, which fixes it.
But... If then FM Volume Overdrive is enabled, the FM signal itself is again processed at 44.1/48 kHz, because the remaining peaks will be removed later anyway.

I'll have to add that the Hard Limit filter works AT LEAST at the input frequency.


Edit: That's not all. There's apparently also a bug in the Hard Limit filter, that only seems to result in spikes at lower latency levels (but maybe it just happens less frequently at higher latencies). Will have to look into this further...

Edit: Found another bug. Now the maximum peak level dropped from +0.6% to +0.1%. I'm going to let Hard Limit handle the signal now as if it's 0.15% louder (to be on the safe side) to avoid distortions. That's only 0.01-0.02 dB softer - and only when Hard Limit needs to limit anyway.

With these changes, the red bars seem to be gone now. I'm going to build an update now, will post it in about an hour. If anyone still sees red output bars with the updated version (with Hard Limit turned on), please let me know...

New version uploaded as BETA3A.


Remark about FM output
The FM processing with "FM Overdrive > 101%" has changed.

Before, Loudness was limiting the sound without oversampling. Now it is oversampling - which means that it gives a stronger peak protection. This may slightly hurt the output quality. At the same time, you should be able to set FM Overdrive to a higher level than before without getting artifacts because of the better peak protection.

If the quality has reduced, lowering Loudness and increasing FM Overdrive by the same percentage should give a result close to the sound of the previous versions. (So say Loudness = 3.00, FM Overdrive = 105% --> /1.02, x 1.02 gives Loudness = 2.94, FM Overdrive = 107%).

If the quality has indeed reduced and this solution isn't enough to reach the same quality level, please let me know!


Edit: I just did a quick comparison myself, and the difference seems to be smaller than I had feared.