Date: Mon, 1 Sep 2014 15:07:32 +0100
From: w.boeke(a)upcmail.nl
To: linux-audio-dev(a)lists.linuxaudio.org
Subject: Re: [LAD] Software sound
Hi Nick,
Sounds interesting, but also rather vague.
Vague? Yeah, I could go along with that. The thing is, how do you describe a sound quality
in words? I have heard people compare filter variants as 'fruitier' or
'squelchier' than others.
Whatever words do it for you, take them. The alternative is not that difficult: rig up a
synth that can select between Chamberlain and other filter algorithms and listen to them.
They all have really different qualities and personally I don't think it is as simple
as adding sub-harmonics.
If the differences between Moog and Chamberlin are
subtle, then Moog isn't worth its extra CPU cycles.
Again, you have to decide that for yourself, I would definitely rate Fons' and
Huovillainen's algorithms as more than worth the extra CPU but I accept that it is
subjective. There are plenty of cases where using a Chamberlain in a synth that is buried
in the mix will hide its deficiencies. Use it as a solo/lead instrument and it will be
lacking.
'Warmth' depends on the lower harmonics. If
you are aiming for warmth then start with a base signal with more lower harmonics, e.g. a
square wave i.s.o. a pulse. Also equalizing and a suitable
amplifier are important. And the ultimate way to get warmth is to add a small amount of
1/2 or 2/3 harmonics. In software this is easy, for real instruments it's impossible!
I don't think this really works, it is akin to just lowering the input signals by some
given divisor. It does not address the non-linear aspects of the filter and it does not
address how the irregularities of the filter change over the cut-off range whilst it is
being driven by a modulation signal (env/pressure/etc) - these are both aspects of the
above algorithms that are not addressed by Chamberlain filters.
Can't help you with your questions on input signals, frequencies, etc. I don't
have them and I refer back to describing a sound as to whether these parameters are
relevant. I used to be a musician playing in bands, then later started writing software. A
few years down the line I used to records stuff, look/edit the sampled waves and got to
the point where I would think 'man, you have to come and look at this sound!'
At that point I gave up on being a musician. When I stopped getting my ears around the
sound then making music lost much of its charm.....
Nick