Introduction:
The Jupiter Filter is a 3-band compressor and a maximizer (limiter).
Multiband compression is a technique mostly used in professional mastering studios, and most
software available today, that claims to do proper multiband compression, doesn't a very
good job. Only the hardware units availble, seems to produce an acceptable quality.
Also, multiband compression usually consists of a band separation filter, several compressors,
and finally a limiter in the end. Adjusting three or four compressors at once is a rather
complex task, especially considering how difficult it can be, adjusting a normal old-fashioned
compressor. If multi-band compression is to be practically usable to the mainstream user, it
must be simplified.
These are the main reasons why I wrote the "Jupiter" filter. It combines high quality filters
and compressors with a fairly simple user interface, and there are even some presets for those
not interested in too much knob-twitching.
The major advantages of the Jupiter filter, compared to todays multi band compressors are:
- Phase-correct band separation (no flaging or phasing artifacts)
- Better compressor-algorithm (it's based on the well known "Joachims Compressor")
- Simple userinterface (ratio, attack & release controls all 3 compressors at once.)
- It's absolutely free.
- It's a native Buzz plugin.
But there are also some disadvantages, though:
- The signal is being delayed 16384 samples (because of the band-separation method)
- This kind of quality requires almost 1 Mb memory, and a lot of CPU power!
Because of the delay and the nature of this plugin in general, I recommend using this
effect as the last master effect before the Buzz master output. A little tip:
If you set the "solo mode" on "bypass", the entire Jupiter filter is bypass, and there's
no delay. This makes it easier to use Buzz (editing patters etc.)
I hope you'll enjoy this plug-in - it sure was a bitch writing it! ;-)
So how does it work?
+------------+
/ | compressor |
/ +------------+ \
+------------+ / \ +---------+
| | +------------+ \ | |
--- signal --> | band- | ---- | compressor | --->--- | limiter | --- output -->
| separation | +------------+ / | |
| | \ / +---------+
+------------+ \ +------------+ /
| compressor | /
+------------+
The input signal is divided into bas, middle and treble. The these three signals are
fed into three separate compressors. Then the signal is mixed together (you can
control how much of the three signals you want, by using the "out lo", mid hi sliders.)
Finally the signal is sent through a limiter, to avoid unwanted transients, that may
occur because of the compressors attack time settings.
I recommend using the VUmeter.exe
for monitoring what you do with the Jupiter filter. Especially whatch page 4 (press 4 in the VUmeter).
Note: This tool requires that you can somehow route the signal back to the input of your soundcard,
without causing feedback.
A note on CPU usage:
As explained above, this effect uses a lot of CPU power, because of the complex computations it performs.
The code is really optimized, and it simply just can't be done any faster. This poses a lot of
problems. Using the WaveOut driver you need appx. a 4-500 MHz computer, but 700+ is recommended. If
you're using ASIO, there may be even bigger problems, and here I'd like to quote a fellow Buzz developer,
Rymix, who helped shed some light on this problem:
It is soley because the ASIO drivers are not stable. They tend to screw up a bit when
the cpu is heavily taxed, which the jupiter tends to cause. All it is is an output
driver. A typical machine should not be able to cause it to fail, unless something is
wrong with the driver itself. What seems to occur is the driver's buffering mechanism
becomes unstable when it is forced to become unsyncronized. That's why all the skipping
and such occurs. On my home machine, it will eventually cause buzz to lockup my entire
machine. It is not the fault of Jupiter. =) 2001-10-30 by rymix
DISCLAIMER:
This software may be distrbuted freely. The author of this software cannot be held
responsible for any damage caused directly or indirectly by using this software.
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