[Fpga-synth] phLUTe

[Eric Brombaugh]

Scott Gravenhorst wrote:

>> 1) What software did you use to do the block diagram on the Wiki page? I 
>> like the way it looks and am always on the lookout for something better 
>> than what I use right now (Powerpoint).
> 
> Heh heh heh - hold on to your sides.  Microsoft PAINTBRUSH.  I do schematics with PB
> too.  (c;

Hoo boy - that's hardcore! I'd like something that at least has 
automatic arrows. I think that the first real computer graphics programs 
I used were MacPaint & MacDraw back on the ancient 128k Macs - I've 
never found anything that worked as nicely or simply. PPT is OK though, 
and OpenOffice has a decent work-alike.

>> 2) I haven't used LaGrange interpolators before. Do you have a link or 
>> reference to the structure you used here?
> 
> I found this very complete and extremely helpful:
> 
> http://www.acoustics.hut.fi/~vpv/publications/vesan_vaitos/ch3_pt2_lagrange.pdf
> 
> As you can tell from that sample, the tuning is precise enough for music.

Yes - those seem to work just fine. In my wireless communications work I 
use something called a 'Farrow Interpolator' - it's got decent SNR and 
distortion characteristics but it's fairly resource intensive (read 
'complicated'). I'm interested in learning simpler structures.

Thanks for the pointers.

Eric