In fact, there are ways of generating nearly band-limited signals
almost that cheaply, which can be smoothly dynamically changed.
We had a paper on one such method at the last DAFx and another
under review discussing a more generalised solution. Also currently
working on a related idea for resonant cases.

Remember that Buzz is actually the first algorithm from way back in
1969 that started it all. The development of distortion synthesis is
very rich and full of elegant solutions.

Victor

----- Original Message ----- 
From: "Richard Dobson" 
To: 
Sent: Monday, November 24, 2008 6:00 PM
Subject: [Csnd] Re: UDO question..


> Note that (as indicated in the docs) the buzz algorithm by its nature does 
> not support the smooth fade in/out of harmonics.  It uses what is called a 
> "closed-form solution" to the otherwise expensive arithmetic of generating 
> N partials very inexpensively; it cannot be worked around. The price of 
> this is that N cannot be fractional, so dynamic variations of knh (e.g. in 
> response to a broad  change of pitch) will result in pops.
>
> So  the answer to your student's question is "no". It's something of a 
> Holy Grail question.  Were there such a cheap way of generating 
> dynamically band-limited signals (from which beloved analog waveshapes 
> such as square and sawtooth can be obtained), we would all be using it, 
> and analog-modelled synths would be much cheaper than they are!
>
>
> Richard Dobson
>
>
> Rory Walsh wrote:
>> One of my students was asking if there is a version of the the buzz
>> opcode that has a fade-in for each harmonic so that pops do not occur
>> in the output. I didn't know if there was and couldn't find on in the
>> manual so I set about doing a simple UDO for him. Here's what I have,
>> the problem is explained below:
>>
>
>
>
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe 
> csound" 

Indeed - wish I had been there!  I have wondered how fast it is 
(including DC blocking filter - linear-phase one?), given it requires an 
exp call per sample, and users typically want a synth supporting ~lots~ 
of voices.

Richard Dobson



victor wrote:
> In fact, there are ways of generating nearly band-limited signals
> almost that cheaply, which can be smoothly dynamically changed.
> We had a paper on one such method at the last DAFx and another
> under review discussing a more generalised solution. Also currently
> working on a related idea for resonant cases.
>