MOTM

I have at least two of each filter.  I rarely use the 420s in 
series.  Normally I run them in parallel with slightly different 
settings for a stereo effect.  
I would recommend getting a 440 next, then a 490 and finally a 410 
before getting a second 420.  
Each filter has its own character.  I think the 440 is the sweetest 
sounding and I use it the most.  If I want a more agressive, harsher 
sound I use the 490, like for a lead that has to cut through a dense 
mix.
All Paul's filters sound great.  I'm anxiously awaiting the 480, 450 
and 470 as well.

> All Paul's filters sound great.  I'm anxiously awaiting the 480, 450
> and 470 as well.
What are the latter two (450 & 470)?
Thanks, Jeff

450 - Fixed Filter Bank
470 - SEM filter

Paul S.

--- In motm@yahoogroups.com, "Paul Schreiber" <synth1@a...> wrote:
> 450 - Fixed Filter Bank
> 470 - SEM filter

So what is the general nature of the SEM's filter?  Warm? aggressive?
nasal?  I've never had a chance to play with one and have no idea what
they sound like...

(The only Obie that I've owned is the Xpander, whose filters I didn't
like the sound of at all.  Very flexible though).

Harry

The SEM filter is state variable 2 pole, so is not as dark as a 4 
pole filter. The only other 2 pole available right now from MOTM is 
the 420 (the upcoming 480 will be also).

The SEM has a continuously variable control to morph from LP to BP to 
HP, not sure if you can get to notch too. It can sound nasally if you 
use BP or HP, naturally. Otherwise I'd call it "warmly aggressive" 
<g>. Listen to the Weather Report classic "Birdland" (not the synth 
bass intro which is 2600, but the polyphonic synth brass lines which 
are Obie 4-Voice).

Moe
http://www.hotrodmotm.com

> So what is the general nature of the SEM's filter?  Warm? 
> aggressive? nasal?  I've never had a chance to play with one 
> and have no idea what they sound like...

If you morphed from LP to HP without the BP you would naturally get a notch
in the middle.

John Loffink
The Microtonal Synthesis Web Site
http://www.microtonal-synthesis.com
The Wavemakers Synthesizer Web Site
http://www.wavemakers-synth.com

> -----Original Message-----
> From: mate_stubb [mailto:mate_stubb@...]
> 
> The SEM filter is state variable 2 pole, so is not as dark as a 4
> pole filter. The only other 2 pole available right now from MOTM is
> the 420 (the upcoming 480 will be also).
> 
> The SEM has a continuously variable control to morph from LP to BP to
> HP, not sure if you can get to notch too. It can sound nasally if you
> use BP or HP, naturally. Otherwise I'd call it "warmly aggressive"
> <g>. Listen to the Weather Report classic "Birdland" (not the synth
> bass intro which is 2600, but the polyphonic synth brass lines which
> are Obie 4-Voice).
>

On 12/13/03, cormallen put forth:
>
>  > 470 - SEM filter
>
>So what is the general nature of the SEM's filter?  Warm? aggressive?
>nasal?  I've never had a chance to play with one and have no idea what
>they sound like...

I would describe it as warm, aggressive, and a bit dirty.  It's a 
12dB filter, but more throaty and less nasal than the MS-20.  It is 
also a multimode filter -- LP, HP, BP, BR.  I heard that JH came up 
with a way to make the modes voltage controllable, but I do not know 
if that feature is part of the MOTM-470.

While it was used by Vince Clark, 808 State, and many other artists, 
imho, the best way to hear the sound of the SEM filter is to listen 
to early European techno trance -- many are minimal compositions that 
used SEM in a dominant role.  Pete Namlook even had a project named 
Four Voice.  Unfortunately, almost all of this seminal music is long 
out of print.

Please keep in mind that the sound of an Oberheim [even number}-Voice 
is the result of many different factors besides the filter.  They 
were multitimbrel as well as polyphonic in that each voice had a 
completely separate set of controls, and could cycle through 
different patches using various assignment modes.

>(The only Obie that I've owned is the Xpander, whose filters I didn't
>like the sound of at all.  Very flexible though).

Yes, that's a completely different filter.

> The SEM has a continuously variable control to morph from LP to BP to
> HP, not sure if you can get to notch too.

If you are referring to the original SEM1A's, this is not the case.  The
filter type pot will go continuously from LP to NOTCH to HP.  "Below" LP,
BP is switched in by using the same pot.  Hence, one cannot morph
continuously to BP.  I'm curious to see what Paul comes up with in regards
to this part of the filter, especially under voltage control.

There are 2 other pots for frequency and resonance.  Modulation is either
from envelope 2, the lfo, or an external source (with an appropriate
external connection).
Jeff

The SEM filter is used in many Tangerine Dream and Edgar Froese albums
from the mid 1970s to around 1981. The main synth in Stuntman is
probably a Two voice or Four voice.

Tony