A couple of questions?

while on the subject of plugins…anyone know of a good stereo plugin that doesn’t futz too much with mono compatibility?

Space EFX in the Omnia 6 is probably my favorite.

Thanks, Leif. I will give Spartacus a shot tomorrow night.

So THAT’S what the ITU stokkemasker (sic) is! Are all stokkemasker limiters 256 bands? Or just yours?

I never saw the purpose of 31 bands, btw…much less 256. 😆

Howdy!

Sgeirk,

Normally there’d be no purpose of this many bands, but in this particular case there is. I can’t go into exactly why — don’t want to give away any ideas to the competition. 🙂 As far as i know, there ARE no other stokkemasker limiters. Orban doesn’t have it, and neither does Omnia.

Orban processors usually do OK on the stokkemasker, but it’s more of a side-effect of all the stuff they do to the audio to prevent overloading the final clipper, since their final clipper is immediately audible as soon as it does anything.

If you download MpxTool (live demo version runs with audio for a minute at a time) you can use the RF mode and see exactly what your FM carrier would look like on a spectrum analyzer. The more treble (or stereo), the wider it gets outside of the channel. The FM carrier is supposed to only deviate +/- 75 kHz, and it does, but as it moves, sidebands are created. If it moves really quickly (which it will, if you broadcast something with wide stereo image, due to the high frequency stereo subcarrier getting significant energy), you get extremely wide sidebands.

The Dutch standard (actually it’s a Norwegian standard — Knut Stokke is Norwegian, but afaik the Netherlands is the only country that uses it) is actually VERY well throught through, and valid (in my humble opinion). They place a "mask" on the screen of the spectrum analyzer (the Stokkemasker) while looking at the FM carrier of the station being measured, and run a maximum peak-hold measurement for 5 minutes. If any part of the carrier ever touches the mask, that’s a FAIL. This is a very accurate way of controlling how much ether bandwidth any one station is allowed to occupy — much more accurate than the simple +/- 75 kHz modulation standard most other countries use. It’s easy to verify just how great a disparity the +/- 75 kHz can let slip past, by playing a high frequency tone (let’s say 15 kHz) *inverted* left and right. This will put ALL energy in the stereo subcarrier, and create sidebands WAY off channel (where they’d interfere with neighbouring stations on the dial), and will step all over the stokkemasker (=FAILED test), even though every modulation monitor in North America (for example) would still say 100% (=PASS).

So, the Stokkemasker’s official name is the ITU-R SM.1268-1 standard.

There’s another standard, the ITU BS.412 standard, in use in Germany and some other countries. This standard intends to control occupied bandwidth (and to prevent loudness wars) by specifying a maximum average modulation, measured with a 10 second integration time.

Now, the problem (in my humble opinion) with the BS.412 standard, is that it measures the average modulation of the carrier itself, without taking pre-emphasis into account. This means, more high end = more average modulation = you have to duck the volume. If you happen to have an O6 or an 8500 handy, turn on the BS.412 and play some stuff and listen. You’ll hear it "inexplicably" lower the volume level on bright sections of music! (NOT a fault of the processors — it’s just how the standard is).

I have never heard BS.412 limiting done well enough for me to be happy with, and I don’t have any ideas for how to do it (it may be impossible to do a better job, due to how the standard is written). For this reason, I’ve washed my hands on it (for now anyway) — there IS no BS.412 limiter in BBP. If I can’t do it well, I’ll leave it out — for me it’s that simple. 😉

[quote author=”Celar”]
Leif- I was doing a search for Spartacus to try it out, and Google led me to a comment you wrote on another message board a few months ago. You stressed the importance of using only phase-linear plugins with Breakaway, and that Spartacus is not phase-linear. Can you give a quick summary of the "price to be paid" if one uses a non phase-linear plugin?[/quote]
To be honest, less so than I initially thought, as is evident by the success of the phase rotation plug-ins. I guess I realized I was fighting an uphill battle that was simply too steep — all it takes is using an analog mixer, and you’ve got tilt already — so it may not be worth it.

That being said, when I make a stereo enhancer plug-in (and I will at some point), it WILL be phase linear. Why settle for less? 🙂

I’m also thinking about how to do a High Frequency Aural Exciter plug-in… One that doesn’t alias, like every other plug-in out there. I think I’ve figured it out, but have to finish a couple of other projects first. In any case, I’m really happy I included plug-in support in the Breakaway Pro Products, because it makes it so easy for me to get brand spankin’ new algorithms out to people for testing!

Best,
///Leif

Modman, I don’t understand your question.

The stokkemasker limiter in BBP occasionally limits audio in the L-R subcarrier, and leaves mono audio completely alone.

It does not improve peaks (peak control is already perfect in BBP) — it prevents the FM carrier from being excessivly wide, and as such may also help fringe stereo reception, and may also help mitigating multipath.

///Leif