Suggested as a favourite along with the Wampler Plexi-Drive by Ding on another post, so thought I would take a look at the Ramble FX Marvel Drive 2.2
They're clearly going for a Marshall vibe, and they have some success capturing this through the sound of the video demos.
RAMBLE FX MARVEL DRIVE 2.2 - VERO LAYOUT
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ReplyDeleteThanks！Don't stick to "center bias", adjust to your liking.Marvel uses mixing the normal channel and the bright channel to make the sound more like Plexi amp,Just my opinion，Marvel's design is more of a shortcut than OD3 and BD2's design。
ReplyDeleteThanks Ding
DeleteHello Andrew!
ReplyDeleteI've already managed to put together some projects but I'm still new to the world of handmade and would like to know what the function of these 50k trimmers would be. I've seen it in some projects being used to pass a specific voltage at some point in the project. I wanted to understand if this would be the case or if they are more useful for fine-tuning the timbre. And this SPDT that you show would be a three-terminal ON ON switch with two possible positions, right?
Thanks for the excellent blog!
Hello
DeleteThe 50k trimmers are used as variable resistors on the drains of the J201 JFETs.
While they tend to sound good in pedals, J201s are terrible components when it comes to consistency - specs can vary a lot. The trimmers are a way to make up for this. I'm not sure what voltages the Marvel Drive are set to, normally the drain would be set to around 4.5v as a starting point, and then tuned by ear, or on an oscilloscope. You can set the gain of different stages this way.
Correct: the switch is two position.
I undertand, well, i'll try it! It's been a while that i want to build one Marshall in a Box, and between some projects with difficult components to find and with the sound I wasn't looking for (I was looking for something that was closer to the JCM800 or a Plexi already being pushed by overdrive), This is the closest and easiest to build I've seen! Thanks for the posts and the help!
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