K&K - Pure XLR Preamp [traced]
I have this Preamp because someone wants me to modify it. So I traced it
K&K makes preamps and mics for acoustic guitars, it's a nice and simple design if you're looking for something like this.
Here's the Eagle Schematic and some gutshots. Tell me if I made mistakes!
edit: Changed C14 polarity
K&K makes preamps and mics for acoustic guitars, it's a nice and simple design if you're looking for something like this.
Here's the Eagle Schematic and some gutshots. Tell me if I made mistakes!
edit: Changed C14 polarity
Last edited by Bononoob on 29 Jun 2020, 20:41, edited 1 time in total.
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- marshmellow
- Cap Cooler
Are you sure about R20/R21? I would rather expect 4,7k, 47k, ... There isn't much to point to having an additional pad at the output with a volume control that goes to zero anyway. It only makes it harder for the 4558 to drive such a low load. I don't know if this is meant to plug into a microphone input or a line input, but the reality is many budget mixers or recording interfaces don't always feature line inputs. So with a low impedance microphone input of 1-2k connected, the load gets even worse.
Hey, no probs! No, all 22µF are polarized and oriented like in the schematic.
Yes I'm sure. I checked again they are SMD marked 471. I don't think R20/R21 are pads, the preamp can be powered by phantom power. Maybe you thought V+ was ground? Anyway thanks for checking it out!marshmellow wrote: ↑28 Jun 2020, 10:51 Are you sure about R20/R21? I would rather expect 4,7k, 47k, ... There isn't much to point to having an additional pad at the output with a volume control that goes to zero anyway. It only makes it harder for the 4558 to drive such a low load. I don't know if this is meant to plug into a microphone input or a line input, but the reality is many budget mixers or recording interfaces don't always feature line inputs. So with a low impedance microphone input of 1-2k connected, the load gets even worse.
Science is art. Art is science.
https://electric-canary.com
https://electric-canary.com
- marshmellow
- Cap Cooler
You're right, I completely overlooked the phantom powering .