Eml synthesizers

Typically, yes. They used a 2-pole, 12dB/oct filter. You could get them to
resonate by reducing the resistance in the feedback path.
 


  _____  

From: emlsynth@yahoogroups.com [mailto:emlsynth@yahoogroups.com] On Behalf
Of bill bigrig
Sent: Wednesday, November 02, 2011 6:15 AM
To: emlsynth@yahoogroups.com
Subject: [emlsynth] Re: EML500 filter resonance


  



Howdy,
 
 i've had an EML 500 for many years, ($20 cost), the filter will not
resonate enough to go into oscillation. Is this normal?
Rig

Not a clue. I don't have a 500. But, the 400 filter uses that board. 
Look for a 15K resistor connected to the top of the Q slider.
 
That 15K resistor connects to the input of a 748 quad op amp, two 100K
resistors and a 3.3pF cap.
 
The 100K resistor in parallel with the 3.3pF cap is the feedback limiting
resistor from the LP output back to the network input.
 
Reduce the 100K.


  _____  

From: emlsynth@yahoogroups.com [mailto:emlsynth@yahoogroups.com] On Behalf
Of bill bigrig
Sent: Wednesday, November 02, 2011 10:10 AM
To: emlsynth@yahoogroups.com
Subject: RE: [emlsynth] Re: EML500 filter resonance


  



Ressistance in the feed back path eh? Any hints what components that
resistor would be between?
rig

Thank you!
rrig


________________________________
From: George Mattson <axisair@...>
To: emlsynth@yahoogroups.com
Sent: Wednesday, November 2, 2011 10:55 AM
Subject: RE: [emlsynth] Re: EML500 filter resonance


  
Not a clue. I don't have a 500. But, the 400 filter uses that board. 
Look for a 15K resistor connected to the top of the Q slider.
 
That 15K resistor connects to the input of a 748 quad op amp, two 100K resistors and a 3.3pF cap.
 
The 100K resistor in parallel with the 3.3pF cap is the feedback limiting resistor from the LP output back to the network input.
 
Reduce the 100K.

>________________________________
>From: emlsynth@yahoogroups.com [mailto:emlsynth@yahoogroups.com] On Behalf Of bill bigrig
>Sent: Wednesday, November 02, 2011 10:10 AM
>To: emlsynth@yahoogroups.com
>Subject: RE: [emlsynth] Re: EML500 filter resonance
>
>  
>Ressistance in the feed back path eh? Any hints what components that resistor would be between?
>rig