SOLVED Decadence Preamp - Unity Gain?

[finebyfine]

I boxed up the Decadence Preamp last night and it sounds awesome but I'm not getting unity gain until maybe 2 or 3 o'clock on volume with everything else at noon. Just wondering if that's normal

 

[Robert]

I believe it is normal, yes.

The build doc for the DeadEndFX version suggests increasing R11 (33K) to 150K to increase the overall output.

I left it at the stock value on the PCB but plan to make a note of that in the PDF.

 

[finebyfine]

Thank you so much @Robert - I'm more than fine with non unity on the one I'm keeping for myself but within 5 minutes of posting about my build I got a commission and feel like that's worth clearing up for that one.

Edit: gonna tag this as solved

 

[Robert]

If for some reason that doesn't cut it let me know.

I'm hoping to have the doc posted in the next couple days.

 

[finebyfine]

Will do! Also too lazy to take good enough pictures of mine for a proper build report thread but just gotta say god damn this thing might have dethroned the rat for my favorite distortion

 

[MichaelW]

I boxed up the Decadence Preamp last night and it sounds awesome but I'm not getting unity gain until maybe 2 or 3 o'clock on volume with everything else at noon. Just wondering if that's normal

So what exactly does this preamp do/sound like? I understand it became a "thing" due to QOTSA's use but I'm not familiar with their music or sound.

 

[finebyfine]

So what exactly does this preamp do/sound like? I understand it became a "thing" due to QOTSA's use but I'm not familiar with their music or sound.

It sounds like an even shittier Rat, in the best way possible. I'll try to do a proper build report in the next couple of days.

 

[scheffehcs]

So what exactly does this preamp do/sound like? I understand it became a "thing" due to QOTSA's use but I'm not familiar with their music or sound.

I’ll probably finish mine up tonight or tomorrow, I’ll post a demo when I do. Yeah Josh Homme said this amp was his secret weapon, and since he does get great guitar tones, everyone is interested (myself included). Here’s a dude on YouTube showing off the amp with some Queens riffs

 

[maertz13]

replaced 33k with 150k, even with the volume maxed it's below unity

 

[Fama]

replaced 33k with 150k, even with the volume maxed it's below unity

I suggest you start your own troubleshooting thread. Read the stickied threads first, we need good quality pictures of the board to spot any issues with soldering or incorrect components (or orientations). Also mention if you subbed any components for others. Also, which 33k resistor did you replace with 150k? It should have been R18 in the updated layout.

 

[maertz13]

I suggest you start your own troubleshooting thread. Read the stickied threads first, we need good quality pictures of the board to spot any issues with soldering or incorrect components (or orientations). Also mention if you subbed any components for others. Also, which 33k resistor did you replace with 150k? It should have been R18 in the updated layout.

it was R18, and all it did was raise the overdrive threshold on both channels. clean was crunch and distortion was absurd distortion. no affect on the output volume