HammondWiki - Diff: Kons12AX7basedEQ&OverdriveCircuit

Differences between version 3 and previous revision of Kons12AX7basedEQ&OverdriveCircuit.

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Newer page: version 3 Last edited on March 29, 2006 3:16 pm. by
Older page: version 2 Last edited on March 29, 2006 3:00 pm. by
@@ -67,14 +67,16 @@
 When it is set to the fully clockwise position, 
 the full HT voltage goes to the plate B for the loudest output level. 
 Even with this setting you can still get a full overdrive sound when the gain overdrive control is set to the fully clockwise position. 
  
-After the signal has passed out of the second stage of the 12AX7 it goes to the output warming control. This is basically a passive high cut control similar to a passive tone control but there is a sweet spot setting at lower end of the range at around 9 o'clock where there is the effect of a bottom boost which adds depth to the sound and the top end of the distortion is smoothed out for a sweeter, more '' vintage '' sounding overdrive effect because this output warming control brings a grounding 22 nf capacitor to the signal coming from the plate of the 12AX7 valve and it affects the way that the treble distorts when the second stage of the 12AX7 valve is overdriven. I normally play my 1963 C3 in my room at a comfortable volume level and at these mild volume levels , setting the output warming control to the 9 o'clock position produces a very nice sounding chunky bottom end combined with a sweeter overdrive tone that sounds very pleasant. If you do set the output warming control to the 9 o'clock position then setting the post overdrive EQ bass control down to around the 9 o'clock position will produce a more or less '' flat '' bass response . All of this is a matter of personal taste , the actual Leslie or external amplifier that the organ is being played through and the room acoustics. 
+After the signal has passed out of the second stage of the 12AX7 it goes to the output warming control. This is basically a passive high cut control similar to a passive tone control but there is a sweet spot setting at lower end of the range at around 9 o'clock where there is the effect of a bottom boost which adds depth to the sound and the top end of the distortion is smoothed out for a sweeter, more '' vintage '' sounding overdrive effect because this output warming control brings a grounding 22 nf capacitor to the signal coming from the plate of the 12AX7 valve and it affects the way that the treble distorts when the second stage of the 12AX7 valve is overdriven. I normally play my 1963 C3 in my room at a comfortable volume level and at these mild volume levels , setting the output warming control to the 9 o'clock position produces a very nice sounding chunky bottom end combined with a sweeter overdrive tone that sounds very pleasant. If you do set the output warming control to the 9 o'clock position then setting the post overdrive EQ bass control down to around the 9 o'clock position  
+ will produce a more or less '' flat '' bass response.  
+ All of this is a matter of personal taste, the actual Leslie or external amplifier that the organ is being played through and the room acoustics. 
  
-BY THE WAY , although I have specified a 22 nf capacitor on the output warming control , you can experiment with other capacitor values to get the type of sound that you like. I have added a 1 pole , 12 position rotary switch with the following capacitor values : 1 nf , 2.2 nf . 3.3 nf , 4.7 nf , 5.6 nf , 8.2 nf , 10 nf , 15 nf , 22 nf , 33 nf , 47 nf , and 82 nf. 
- This variable capacitors rotary switch adds a lot of flexibility to the output warming effect of the overdrive sound. 
+*By the way* , although I have specified a 22 nf capacitor on the output warming control , you can experiment with other capacitor values to get the type of sound that you like. I have added a 1 pole , 12 position rotary switch with the following capacitor values: 1 nf, 2.2 nf. 3.3 nf, 4.7 nf, 5.6 nf, 8.2 nf, 10 nf, 15 nf, 22 nf, 33 nf, 47 nf, and 82 nf. 
+This variable capacitors rotary switch adds a lot of flexibility to the output warming effect of the overdrive sound. 
  
-If you have a modern treble driver such as the Hammond Suzuki 100 watt ferro fluid driver that is too bright sounding in your Leslie , you can turn down the output warming control to compensate for this. 
+If you have a modern treble driver such as the Hammond Suzuki 100 watt ferro fluid driver that is too bright sounding in your Leslie, you can turn down the output warming control to compensate for this. 
  
 After the output warming control there is the master volume control and after this there is the passive post overdrive EQ bass and treble controls. 
 Set the amount of overdrive that you want with the setting of the expression pedal and the gain/overdrive control and then set the master volume to what ever listening volume level that you like. 
  

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