Ok... so assuming that the (filtered) data drives eight LED's directly,
each bit represents 2x voltage, isn't this 3dB per led? Although not
dBm... so I'd still need to weight the output... (now I'm thinking of that
divide-and-conquer square root algorithm).

-- Rich

On Thu, 9 Mar 2000, Spehro Pefhany wrote:

> Date: Thu, 9 Mar 2000 15:07:14 -0500
> From: Spehro Pefhany <speff@INTERLOG.COM>
> Reply-To: pic microcontroller discussion list <PICLIST@MITVMA.MIT.EDU>
> To: PICLIST@MITVMA.MIT.EDU
> Subject: Re: VU meter
>
> At 11:46 AM 3/9/00 -0800, you wrote:
> >> 1. Subtract DC bias count (= 128) from signal if > 128, subtract signal
>
> >I was planning to sample about 8Khz and run thru simple IIR filter, the
> >output works the bargraph. But the RMS thread has gotten me thinking:
> >would this really do what I need? What exactly the heck is a Volume Unit
> >anyway? Is there an algorithm that makes more sense?
>
> You'll need something like a log response for it to make sense...
>
>
> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
> Spehro Pefhany                                    "The Journey is the reward"
> speff@interlog.com
> Fax:(905) 271-9838                      (small micro system devt hw/sw + mfg)
> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
>