[sdiy] Digital oscillators

[Simon Brouwer]

Seb Francis schreef:
> Antti Huovilainen wrote:
>>
>> 5b) BandLimited StEps (BLEP)
>> For each oscillator reset, sum a bandlimited step with the trivial 
>> saw. The steps are precalculated and stored in a table (can be quite 
>> short when interpolation is used between two phases.
>>
>> Pros: Very good quality. No oversampling required. Can do bandlimited 
>> FM, PWM and sync. Probably the only method that can do audio rate PWM 
>> and sync.
>> Cons: Requires a divide per cycle. Can be complicated: calculating 
>> required table entry is not trivial when using sync or pwm.
>>
>
> For anyone trying to get their head around this (like me!), here's an 
> easily-understandable introduction...
> http://www.slack.net/~ant/bl-synth/

I compiled the sample program from that page. At a high pitch there is 
still a lot of aliasing audible.

Listen to the .wav files at:  
http://simonbr.xs4all.nl/wiki/index.php/Band_limited_synthesis

I wonder if this is the expected result for 32 times oversampling and a 
step length of 16 samples?

-- 
Vriendelijke groet, 
Simon Brouwer. 

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