Stereo Tool

ow, i might have wrong beta.. lol

edit:
Anyway... like you don't need to lower anything when you are using "Phase Difference" correction/calibration (which is similar to TILT correction) you don't need for tilt correction too. At least it should be like that.

Also, you can see that FM TILT correction is not visible on meters and ST scope, there is no need since you anyway need external scope to calibrate soundcard output.

Input TILT correction is visible on ST scope, so you can easy play test squere tone from your player trought your analog chain and easy calibrate.

The output signal needs extra headroom, so if your volume is set close to 1.000 (in the sound card settings - and only there!), you need to set it low enough to handle the peaks that will be added.

If the volume is already set properly for your transmitter, you shouldn't need to change it (well you might be able to increase it a bit once the DC offsets don't cause larger peaks in the signal anymore).

http://www.stereotool.com/download/ster ... ETA003.exe
Stand alone executable (NOT installer!!!)
Changes w.r.t. previous version:
- Tilt can now be changed in 2 directions
- There are now 2 tilt sliders, these can be used to calibrate 2nd order RC filters. So if both your sound card (output) and your transmitter (input) have a highpass filter (condenser+resistor), you should be able to configure it correctly now. How? First make the waveform as flat as possible with the 1st slider. Then use the 2nd slider to remove any bump or hole in the flat areas. You might need to (slightly) adjust the 1st slider again while doing this.

Some first results, reported by users (well, one user actually, eldoradofm):

- If you have a DC straight sound card AND transmitter, don't use output tilt correction or the DC offset can spiral out of control, effectively changing the frequency at which you are transmitting!
- The ESI Juli@ card seems to have a partial DC straight output, meaning: If you constantly send the maximum DC offset, volume 0.4, DC straight transmitter, it should cause a shift of 200 kHz but we measured 100 kHz. So apparently no all the DC offset is removed!

Edit: Juli@ leak current seems to depend on the output signal strength. Oops! Not sure how bad this is (depends a lot on how much DC offset will actually occur, and there should be very little). Anyway, if anyone can shed a light on what's going on here I'ld be really happy. (Basically, @ volume 0.3 the measured voltage is -0.320 to -0.360, at 0.6 it's -1.88 and at 1.0 it's -3.97 - that's with a 0 Hz output signal with no tilt correction).

Edit #2: Still, output of Juli@ on transmitter looks perfect. So not sure if anything more is needed.

Edit #3: First results from several sound card/transmitter combinations look perfect.

Changes in this version:
- Slightly changed sensitivity behavior (les steep drops and rises of bass). Not sure if this is the best possible solution: Alternative might be to let the bass drops start and end INSIDE the area where loud bass is present, or do the same as now but limit the maximum change speed.
- Made tilt configuration a bit easier (less steep changes at the extremes)
- 2nd RC slider is saved now

Stand alone: http://www.stereotool.com/download/ster ... 32-004.exe
DSP: http://www.stereotool.com/download/dsp_ ... 32-004.exe
VST: http://www.stereotool.com/download/vst_ ... 32-004.dll
Cmd: http://www.stereotool.com/download/ster ... 32-004.exe

Older changes:
- Bass sensitivity clipping level drop: If there are both mids and highs, the drop is a bit less strong than before
- Bass sensitivity clipping level drop: Determining more precisely when the clip is needed. So instead of dropping the bass the whole 4096-samples block, it's now only dropped at the locations of this block where there really are mid/high freqs
- Bug reported by Phoenix ( viewtopic.php?f=15&t=4235 ) should be fixed.
- BS412 also needs a max deviation (+/- 75 kHz) display --> Added
- BS412 sometimes caused drops of upto 2.5 dB. This is preset dependent. --> Adding a slider with which you can specify the amount of headroom; by lowering the output level by 0.05 dB the margin for error is already increased by 50% which seems sufficient. Test if adjustment adjust compressors properly.
- Also adding a BS412 slider with which the max deviation can be lowered; this way you can create a denser sound (apparently many commercial stations like that even though they don't gain any loudness) and it protects against spikes when the sound card or path to the transmitter isn't perfect (reason: Many current processors usually clip the signal at around +/- 50 kHz instead of 75, so in many cases the path to the transmitter doesn't have to be perfect). (Partially done, to be added: BS412 must take clipping into account; clipping level adjustment for pilot/rds).
- Something is broken in latency 512.
- Different up speeds for louder end result
- Sound card adjustment for low freqs needed (that was on my todo list anyway, but I'm moving it to the top now).

Planned:
- Check sensitivity


Note: High frequency square waves are NOT good for testing. Use square for low freqs, normal for high (above approx. 100-200 Hz).

Hans didn't mention, in 6.32-004 you can also choose what bands will be included in "vocal protecion" for MB.



Default is still 4-7!

There are several sliders missing in the limiter with the latest beta, are these placed somewhere else (can't find them though) or was it your intention to just remove them altogether?

I don't see any missing sliders? Which version and which sliders?

The latest BETA, VST version. I did found the bass controls that were previously in the limiter section, but there was also this slider for the highs (highs priority?), also in the limiter section, near the bottom on the right.

Changes in this version:
- Added displays so you can see what is being sent out to the sound card (including calibrations)

Question: It seems that if you set Fade to 100% and the 2nd slider to twice the RC value of the first, you still get straight lines without the problems that were caused by slow Fade speeds - tested with tones down to 5 Hz. Have to check this further - I wonder if this is really still true if you're sending something else than test tones. If so, this would make the behavior much better (and I can remove the Fade slider).

Haven't checked VST version yet (sliders are good in other versions)

Stand alone: http://www.stereotool.com/download/ster ... 32-005.exe
DSP: http://www.stereotool.com/download/dsp_ ... 32-005.exe
VST: http://www.stereotool.com/download/vst_ ... 32-005.dll
Cmd: http://www.stereotool.com/download/ster ... 32-005.exe

Older changes:
- Bass sensitivity clipping level drop: If there are both mids and highs, the drop is a bit less strong than before
- Bass sensitivity clipping level drop: Determining more precisely when the clip is needed. So instead of dropping the bass the whole 4096-samples block, it's now only dropped at the locations of this block where there really are mid/high freqs
- Bug reported by Phoenix ( viewtopic.php?f=15&t=4235 ) should be fixed.
- BS412 also needs a max deviation (+/- 75 kHz) display --> Added
- BS412 sometimes caused drops of upto 2.5 dB. This is preset dependent. --> Adding a slider with which you can specify the amount of headroom; by lowering the output level by 0.05 dB the margin for error is already increased by 50% which seems sufficient. Test if adjustment adjust compressors properly.
- Also adding a BS412 slider with which the max deviation can be lowered; this way you can create a denser sound (apparently many commercial stations like that even though they don't gain any loudness) and it protects against spikes when the sound card or path to the transmitter isn't perfect (reason: Many current processors usually clip the signal at around +/- 50 kHz instead of 75, so in many cases the path to the transmitter doesn't have to be perfect). (Partially done, to be added: BS412 must take clipping into account; clipping level adjustment for pilot/rds).
- Something is broken in latency 512.
- Different up speeds for louder end result
- Sound card adjustment for low freqs needed (that was on my todo list anyway, but I'm moving it to the top now).
- Slightly changed sensitivity behavior (les steep drops and rises of bass). Not sure if this is the best possible solution: Alternative might be to let the bass drops start and end INSIDE the area where loud bass is present, or do the same as now but limit the maximum change speed.
- Made tilt configuration a bit easier (less steep changes at the extremes)
- 2nd RC slider is saved now


Planned:
- Check sensitivity


Note: High frequency square waves are NOT good for testing. Use square for low freqs, normal for high (above approx. 100-200 Hz).