What is the advantage of the wiring shown in this image compared to "normal HRM" separate master wiring?
As far as I understand wiring like in this image would result in 1M additional resistance in front of the OD entrance. Wouldn't this significantly reduce the highs?
What is the advantage of the wiring shown in this image compared to "normal HRM" separate master wiring?
As far as I understand wiring like in this image would result in 1M additional resistance in front of the OD entrance. Wouldn't this significantly reduce the highs?
What is the advantage of the wiring shown in this image compared to "normal HRM" separate master wiring?
As far as I understand wiring like in this image would result in 1M additional resistance in front of the OD entrance. Wouldn't this significantly reduce the highs?
Peace,
Markus
No as the 1M is switched out in OD mode.
Thanks a lot for the clarification
Very clever indeed
Shouldn't look at schematics in the middle of the night
Why would you want a 1m resistor in series with a 1m pot?..Doesn't that side of the pot already set up a 1M load?.. Confused
Also if you add the pot why would you even want to keep the 100k/180k whatever resistor to ground?..A voltage divider feeding a voltage divider?? confused further??
I would try this..
Tony
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" The psychics on my bench is the same as Dumble'"
talbany wrote:Why would you want a 1m resistor in series with a 1m pot?..Doesn't that side of the pot already set up a 1M load?.. Confused
Also if you add the pot why would you even want to keep the 100k/180k whatever resistor to ground?..A voltage divider feeding a voltage divider?? confused further??
I would try this..
Tony
Now I'm confused... I'm using your layout for the schematic (yes the 180K needs to go before the 1M). Looking at your layout it shows a 1M in series with the 1M Level control. It's not a voltage divider with the 180K before the 1M, correct???? Are you saying the 180K/1M is not needed with the addition of the second master as there is no need to attenuate the signal before when there is only 1 level control?
Jason .. If you want to keep the circuit identical to that of the layout and add a level to the OD you simply substitute the 1M resistor for a 1M pot.. If you want to keep the 180k to ground there like Brandon has thats great.. this way with the pot dimmed 1M the amp should respond and sound similar to the amp in my layout..the 150k resistor in the schematic I revised is used to set up the load/impedance for the pot's input and also smooths things a bit...
Does this make sense?
BTW.. If you add a 1m level here you will have a 1M pot level feeding a 1M pot Master vol.. I think maybe possibly Dumble wanted to avoid this (By audio standards not a good design)..JMHO
Tony
" The psychics on my bench is the same as Dumble'"
glasman wrote:A couple of hints for creating separate masters for Clean and Overdrive.
1. Float the clean master potentiometer off of ground when OD is enabled. THis is very easy to do if you remember that the OD input is grounded when clean mode is enabled. I simply tap the OD input from the relay and connect it to the ground connection of the clean master. This assumes wiring the clean master before the relay.
When OD is selected the Clean master has the same signal on top and bottom and is taken out of the circuit.
Yup, that is the idea. This idea came about due to my Dual mode non-HRM / HRM amps. Been using this technique for about 5 years.
The only issue I see is the placement of the 180K, But I think you already fixed that in the drawing.
FWIW, I have a 1Meg feeding 1Meg OD master and it sounds FREAKING awesome, no loss of highs (as I would have thought) due to the extra 1M series resistance. Probably due to the 15Meg input impedance of the PI. Without that resistor it would have been impossible to balance the Clean and OD volumes with a single master setup.
Gary
Last edited by glasman on Wed Oct 27, 2010 5:22 pm, edited 1 time in total.
Located in the St Croix River Valley- Afton, MN
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talbany wrote:Jason .. If you want to keep the circuit identical to that of the layout and add a level to the OD you simply substitute the 1M resistor for a 1M pot.. If you want to keep the 180k to ground there like Brandon has thats great.. this way with the pot dimmed 1M the amp should respond and sound similar to the amp in my layout..the 150k resistor in the schematic I revised is used to set up the load/impedance for the pot's input and also smooths things a bit...
Does this make sense?
BTW.. If you add a 1m level here you will have a 1M pot feeding a 1M pot Master vol.. I think maybe possibly Dumble wanted to avoid this (By audio standards not a good design)..JMHO
Tony
Sorry, I think I'm confusing things with my terminology. I don't want to add a level control that feeds a master, I want to add separate masters for the clean & od. The schematic above is splitting the stock "level" control for each channel.
I'm still confused on your comments regarding the 1M resistor as the stock circuit clearly has a 1M feeding a 1M pot:
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