# Glory hole gain mod question



## Bobbyd67 (Jul 3, 2020)

Hi y'all ! I am still waiting for my glory hole boards to arrive... Someone posted a trace of his original KOT gain mod which is basically changing r3 from the paragon boards from 1k to 100k.

This got me thinking ... Since the KOT and the morning glory are basically modified Bluesbreaker circuit could I just change r3 or r4 (don't know which one xD) via a stompswitche to have a makeshift gain mod on my future glory hole ? I plan the socket those resistors anyway and experiment but I thought that maybe someone who actually understand circuit design could help me confirm my idea or point me in a better direction ^^. 

Thanks !


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## phi1 (Jul 3, 2020)

Neither R3 or R4 would give you that mod. The glory hole doesn’t have a resistor in the spot in the circuit where the paragon’s R3 is.

you could clip lug 1 of the drive pot and attach a resistor in between lug 1 of the pot and the pad on the board, and that could also be wired to a stomp switch.


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## Bobbyd67 (Jul 3, 2020)

phi1 said:


> Neither R3 or R4 would give you that mod. The glory hole doesn’t have a resistor in the spot in the circuit where the paragon’s R3 is.
> 
> you could clip lug 1 of the drive pot and attach a resistor in between lug 1 of the pot and the pad on the board, and that could also be wired to a stomp switch.



Yeah it's true that the r3 resistor isn't there on the glory hole, and using a 3pdt stompswitche I could use one row for the jumper for stock, one row for the added gain resistor and one row for the LED when gain more is on ^^. I will probably go that way instead of my initial mod of swapping one of the 2 resistors via the switch . Thanks !


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## phi1 (Jul 3, 2020)

There’s an easier and probably better way. Hard wire the 100k in there, and then just use two lugs of one row of the stomp to short it out for normal mode. And another row for the led.

R3 and R4 work the opposite way, where decreasing the value increases the gain. But these values also affect frequency response. 

The morning glory and king of tone are both based on the BB, but different versions, hence the different values at R3 and R4, which are part of what gives the morning glory it’s brighter tone. 

there will be a volume jump when you hit the stomp for higher gain, so consider if that’s useful to you.


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