PANTHER OD-30 Overdrive Schematic  [schematic]

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Manfred
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Post by Manfred »

The PANTHER OD-30 Overdrive has the same Layout as the REDSON 12 OVERDRIVE 12 has.
The schematic have minor differences.
Very few components has been changed.
The additional cipping part, diodes and the 10kOhms resistor in seriell , has been omitted.
PantherOD-30OverdriveShot1.jpg
PantherOD-30OverdriveShot2.jpg
PantherOD-30_Components.jpg
PantherOD-30_OverdriveLayout.JPG
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PantherOD-30_OverdriveSchematic.JPG

Macimalac
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Post by Macimalac »

The 1M resistor at the switching circuit should be connected to the other end of the 100k resistor, asit is on the PCB.

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Post by Manfred »

Macimalac wrote:The 1M resistor at the switching circuit should be connected to the other end of the 100k resistor, asit is on the PCB.
Thanks a lot for the hint.


Drawing error in the switching control part fixed.
PantherOD-30_Overdrive12_Schematic.JPG

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mirosol
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Post by mirosol »

I believe this in the same circuit as for Digiplay OD-30, which i happen to have. Guess i'm correct :) https://www.effectsdatabase.com/model/di ... 30#related

Anyway. I think it's very nice sounding OD with decent "bluesy" vibe to its tone. Maybe even to a degree that it may be an overlooked gem. I drew a stripboard layout for the circuit. I assume the resistor from non-inverting input of the clipping amp to vref is around 10K. Unverified, but seems ok.
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Post by mirosol »

Built the layout above myself, so consider it verified. However, if you decide to build one, go for C10K as the drive pot and 22K for the "12K*". Sounds really good to my ears.
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Post by Lord Ashram »

Hi there and Thanks a lot for the work and information!

Sorry to "wake the dead"...just for my understanding, as I am still learning, not knowing:
The schematic says Level 1 to virtual ground, right? Does it make a difference if it´s connected to regular ground like the stripboard-layout says?

The two 220k after the Level-pot in the schematic - Do they change the tone or the level of the signal? It´s left out, I see. But does it alter something?

I´m having a problem re-building/copying the Overdrive 12. It just does not sound right/the same. It´s a lot harsher and the signal is a lot lower than original. So I´m trying to figure out what to change to make it sound right...

Thanks a lot again!
Tobias

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Post by Manfred »

The schematic says Level 1 to virtual ground, right? Does it make a difference if it´s connected to regular ground like the stripboard-layout says?
No this makes no difference, the signal voltage is short-circuited by the 10uF capacitor and thereby connected to ground.
The two 220k after the Level-pot in the schematic - Do they change the tone or the level of the signal?
The 220k resistors are partly responsible for the lower cut-off frequency.
It´s a lot harsher and the signal is a lot lower than original.
Which operational amplifier and which clipping diodes did you use?

The layout has the same error as the one from the RedsonOverdrive12 here the corrected version:
PantherOD_30_Layout_2.JPG
Ready to print PDF-files:
PantherOD_30_PCB_ComponentSide.pdf
(19.48 KiB) Downloaded 16 times
PantherOD_30_PCB_SolderSide.pdf
(12.3 KiB) Downloaded 20 times
SprintLayout 6.0-File:
PantherOD_30.zip
(31.97 KiB) Downloaded 18 times

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Post by Lord Ashram »

Hi and Thanks for the quick response!

I used a JRC4558 and regular 1N914 diodes. I also found it to be less loud in comparison.
Since I didn´t want to desolder all the parts from the "holy grail" I bought a Redson12 Overdrive from reverb and found out it had different diodes (not readable), different IC (6558) and different caps in...and it also didn´t sound right... :( Wasted money.
Thanks again!

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Post by Lord Ashram »

Oh, sorry for not including this in my last post - I built a TrueBypass-Version just like Miro did (only that I built the Redson 12 OD diode-configuration) and also left out the 2 220k resistors since I thought they were just necessary for the switching. Taking a closer look in what should be the mistake in my build I wondered if the two resistors could make a difference. Maybe you can explain to me what it does... if it does something?
Cheers
Tobias

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Post by Manfred »

If you leave out the 220k resistor the signal will be short circuited to ground in the bypassed state.
SwitchingBypassedEffekt.jpg

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Post by Lord Ashram »

Ok, Thanks a lot for the explanation!!
Seems like I figured it out right.
But still - does it alter the tone if those two 220k in a row are left out in the TrueBypass-Version?

Thanks a lot again, once I have it sounding like the original I will post my strip-board version of the Redson 12 OD . Promised!

Cheers
Tobias

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Post by Manfred »

But still - does it alter the tone if those two 220k in a row are left out in the TrueBypass-Version?
I ran a simulation in effect state with 2x220k and with 44k for different potentiometer settings
and it did not change anything at the lower cutoff frequency as I expected. It was around 35Hz.

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