Emu XL-7 & MP-7 User's Group

The USB interface is so you can plug it into a PC and it will look like a USB 
audio device (a pair of speakers) so that any sound you can get your computer to 
make can be 'played' into the E-mu module and through its effects.

The external audio (as well as audio from a computer through the USB interface) 
would be 'waveforms' on a ROM. You could have any number of presets ('ROM 
Instruments') that have a particular filter setting using these waves, but to 
get the exact set of patch cords that you want to have [unless the ROM presets 
do __exactly__ what you want] you would probably need to create user patches 
using these waveforms. [for example, you could have a patch/preset that has all 
four waveforms turned on ("being played") when a single note is played, or break 
up the keyboard into different regions each with a separate group of waves being 
played using overlays]

Essentially the idea is that when the E-mu module accesses a certain memory 
range in the SIMM's waveform ROM region then it actually returns the latest 
sample from an audio source. You could theoretically have many audio sources 
being made available this way but there are practical limitations... THe preset 
memory on this SIMM tells the module where the 'waveforms' are and the module is 
none the wiser - the waves are dynamically generated rather than ROM encoded. It 
also has some patches/presets to get you started but when it comes to effects 
every one has different (IMO bad) taste so there will be user presets/patches 
using those 'waveforms' that will have the effects being used in your favorite 
way ;-)

Since all the processing on the module is done digitally, its very (VERY) 
unlikely that the module would be damaged in any way. However if you put 
something harsh (at high volume) into your speakers - then that's another 
matter.

Turning this into a sampler is not a big deal (just need some memory). You could 
even have audio downloaded into the memory through USB and stored in FLASH (kind 
of like the other SIMM I'm making). However, making it a useful sampler is 
difficult short of creating a new version of OS to handle the stop/start and 
edit of it all. 


My investigation (with a P2K) module showed that the OS does not access the 
SIMMs after boot. This is probably just a software thing to give maximum 
bandwidth to the voices (pushing the limits of ROM access as it is). 
However changing that would be necessary to make a useful sampler of the E-mu 
modules




________________________________
From: steve_the_composer <smw-mail@...>
To: xl7@yahoogroups.com
Sent: Fri, November 26, 2010 2:53:18 AM
Subject: [xl7] Re: Modding: ext. audio being affected by xl sounds

  
(1) What would the usb interface do? 
(2) With the audio plug, would the external audio in appear as a ROM Instrument?
(3) With the audio plug, would there be 4 external audio ins (possibly appearing 
as 4 discrete ROM instruments)?
(4) Is there any risk that the levels of the uadio ins would damage the E-Mu?
Thanks.
Steve

--- In xl7@yahoogroups.com, Jack Pratt <woodsworth1@...> wrote:
>
> I suppose that anything is possible...
> Â 
> Would anyone be interested in a 'SIMM' that had a usb interface and a 2.5mm 
> audio plug which allows you to have audio input directly from the outside 
>and/or 
>
> from a computer as a USB audio device? It would give you four audio channels 
>(2 
>
> stereo channels) which are just passed to the module for processing live.
> Â 
> This is not sampling just making a 'wave' available from outside the box.
> Â 
> The only problem [?] is that the waves would only be available while the module 
>
> is playing a note. That is, the SIMM is configured with four 'waves' which can 

> be put in presets, and the SIMM offers up 'live audio' instead of something 
>from 
>
> ROM. You can create your own presets with those waveforms so that you can 
>select 
>
> the filters/effects that you want to apply. [but sound only comes out when you 
>
> play a note]
> Â 
> How much would you pay for such a thing?
> Â 
> I was thinking of implementing such a thing in any case, but I can raise the 
> priority if there's sufficient interest. 
> 
> 
> 
> 
> ________________________________
> From: scodoha04 <scott.d.harvey@...>
> To: xl7@yahoogroups.com
> Sent: Thu, November 25, 2010 12:12:29 AM
> Subject: [xl7] Re: Modding: ext. audio being affected by xl sounds
> 
> Â  
> That seemed intuitive but good to hear it from the source.
> 
> A better question is are there any equivalent external effects boxes which can 

> mimic the z-filters?
> 
> For speculation, what sorts of things can't the z-filters do that can be 
> performed with external effects?
> 
> --- In xl7@yahoogroups.com, Aaron Eppolito <synthesis77@> wrote:
> >
> > The returns on the sub-outs are summed with the mains in the analog domain. 
>All 
>
> >of the XL-7's processing is in the digital domain. There is no A/D.
> > 
> > In short: it can't be done.
> > 
> > -Aaron
> > 
> > On Nov 22, 2010, at 1:45 AM, Nico Liukko wrote:
> > 
> > > first of all i would like to know if there are any hardware schematics for 

> >the xl 7.
> > > 
> > > second is that i wanna mod the xl 7 with external audio in so the external 

> >audio could be affected by the crazy stunts this machine can pull off.
> > > 
> > > as it is now, i can use the sub outs for external audio use but the 
>external 
>
> >audio isnt affected by the effects or crazy stuff this machine can do by soft 

> >routing.
> > > 
> > > any thoughts?
> >
>