SOLVED Powder Blue 1u5 MLCC

[pcb rookie]

The build docs for the Powder Blue call for 1u5 MLCC caps. Is there a tone related or specific reason for going MLCC or could it be replaced with box film cap?

https://docs.pedalpcb.com/project/PowderBlue-PedalPCB.pdf

 

[spi]

I think they just aren't common in that size. If you can find them, use 'em.

 

[Stickman393]

I'd venture a guess that it's more about cost than anything else,

Ceramics at 1.5uF can be very cheap. Film, less so.

Looks like Bugg provided plenty of space for either choice, though.

 

[pcb rookie]

I'd venture a guess that it's more about cost than anything else,

Ceramics at 1.5uF can be very cheap. Film, less so.

Looks like Bugg provided plenty of space for either choice, though.

I think they just aren't common in that size. If you can find them, use 'em.

Both availability and price makes sense to make selection. I ended up going with the box film caps. They were twice the price of MLCC's but I just needed a two for this built so that did not make a difference. I would have though a little longer if that value was to be needed on multiple projects or if space on the PCB was to be an issue.

 

[music6000]

Both availability and price makes sense to make selection. I ended up going with the box film caps. They were twice the price of MLCC's but I just needed a two for this built so that did not make a difference. I would have though a little longer if that value was to be needed on multiple projects or if space on the PCB was to be an issue.

I used Wima 1.5uF in my Build, a Great Pedal :
https://forum.pedalpcb.com/threads/powder-blue-overdrive-pedal.9596/

 

[pcb rookie]

I used Wima 1.5uF in my Build, a Great Pedal :
https://forum.pedalpcb.com/threads/powder-blue-overdrive-pedal.9596/

exactly what I went for!

 

[giovanni]

Working on this right now. These 1.5uF caps seem hard to find and pricey ($0.70 on Tayda)! I considered putting a 1.5 and a .47 in parallel but the two leads do not fit in the hole and I wanted to avoid some frustrating jerry-rigging. Has anybody tried just using 1uF instead? I see that one of them affects the bass control and the other is a coupling capacitor. I would expect the latter to be easily replaceable? But maybe not so much the former?

 

[jimilee]

Working on this right now. These 1.5uF caps seem hard to find and pricey ($0.70 on Tayda)! I considered putting a 1.5 and a .47 in parallel but the two leads do not fit in the hole and I wanted to avoid some frustrating jerry-rigging. Has anybody tried just using 1uF instead? I see that one of them affects the bass control and the other is a coupling capacitor. I would expect the latter to be easily replaceable? But maybe not so much the former?

Yep, that’s fine. I suspect some of the odd values come from precise math, at some point, or that’s all they had laying around when designing the circuit.

 

[giovanni]

Yep, that’s fine. I suspect some of the odd values come from precise math, at some point, or that’s all they had laying around when designing the circuit.

Yeah I was trying to calculate the cutoff frequency and for the bass one I think the difference would be between 20 and 30 Hz cutoff (this is sort of hand wavy since I was just looking at the pot and cap). I didn’t do the math for the coupling cap. I was considering simulating the circuit with spice to see the frequency response difference.