[comp.sys.amiga] how to improve sound capabilities

carli@munich.dec.com (Bernardo da Vinci - the Amiga genius) (08/10/88)

   
    
    
    Has anyone the Amazing Computing issue (april?) with an article
    how to improve the sound capabilities of the amiga?
    (ya know that nasty filter that won't pass any frequences higher
    than 7kHz...)
    I'm desperately seeking for a cheap solution to set the cut off
    frequency of the filter to 14kHz or higher. It shouldn't be a hard job,
    but without any printsets it isn't a simple task (for me).
    Maybe someone tried it allready - I don't want to reinvent the wheel.
    As far as I know can this filter be turned off on newer A500 or A2000
    with the LED PD-Programm. So CATS, what do I have to do ???

    Any recommendations would be appreciated.
    
    Bernhard
    

lauren@cbmvax.UUCP (Lauren Brown CATS) (08/16/88)

In article <1856.AA1856@heimat> sneakers@heimat.UUCP (Dan "Sneakers" Schein) writes:
>[If you can read this line, then your line eaters on the blink!]
>
>In Message <8808100911.AA07219@decwrl.dec.com>, carli@munich.dec.com (Bernardo da Vinci - the Amiga genius) writes:
>   
>>    I'm desperately seeking for a cheap solution to set the cut off
>>    frequency of the filter to 14kHz or higher. It shouldn't be a hard job,
>>    but without any printsets it isn't a simple task (for me).
>>    Maybe someone tried it allready - I don't want to reinvent the wheel.
>>    As far as I know can this filter be turned off on newer A500 or A2000
>>    with the LED PD-Programm. So CATS, what do I have to do ???
>>
>     I wrote just such an article with a A1000 hardware hack & A2000/A500 'C'
>	 code examples when I was at CBM. It was for a (then) upcomming AmigaMail,
>	 im not sure if it was published yet or not. Lauren or Carolyn?
>
>>    Any recommendations would be appreciated.
>>    
>>    Bernhard
>    
>
>--
> Dan "Sneakers" Schein     {alegra|amiga|rutgers|uunet}!cbmvax!heimat!sneakers

Dan wrote an article called "Amiga Audio Cutoff Filter, which we published in
the March/April issue of AmigaMail.

Sorry, we do not make back issues available to non-subscribers (our supply is
limited). If you would like to subscribe to AmigaMail, send a check for
U.S $20 (22.50 in Canada, 25.00 all other global points) to:

				CATS-Orders
				1200 Wilson Drive
				West Chester, PA 19380

At the same time, you can request any back copy you might be interested
in. As long as we still have a supply, we will fulfill your request.
-- 
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Lauren Brown      -- CBM   >>Amiga Technical Support<<
                     UUCP  ...{allegra,caip,ihnp4,seismo}!cbmvax!lauren 
                     PHONE 215-431-9100
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

mriley@pnet02.cts.com (Mark Riley) (08/30/88)

To disable the audio filter on an Amiga 1000 snip one leg of capacitors
C103 & C104.  These capacitors should be right next to each other.  If
you are more ambitious you could hook up a DPST switch to switch the
filter capacitors in and out.  Make sure you use shielded cable that has
two internal conductors for each capacitor.  The shielding should be
hooked up to ground.  BTW, the capacitors are located beneath the
"daughter board" so you'll have to remove it first to access the
two little beasties.  If for some reason this doesn't work for your
1000 version than all you'll need to do is put a tad of solder on the
snipped leg and all will be back to normal.

-Mark-

UUCP: {ames!elroy, <backbone>}!crash!gryphon!pnet02!mriley
INET: mriley@pnet02.cts.com

"Hey, I don't _use_ programs, I write them..."  ;-)