Author Topic: Bumblebee VFE - Pre MBP Build Doc  (Read 338 times)


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Bumblebee VFE - Pre MBP Build Doc
« on: June 21, 2018, 11:33:30 PM »
For those who bought the Bumblebee VFE main board from me, I want to clarify things up. Finally, I got everything tweaked up nicely and got the help from Peter.

A 1nf capacitor should be placed between pins 6 & 7 of the 4558 op-amp to reduce distortion bleed-through from the envelope trigger circuit. Also, do not install the JFET trimmer. Instead, install a jumper between the left-middle pin of that trimmer and its bottom pin. 

For my first build, I did 1nF cap placed between 6 and 7 of the 4558. The second build, I didn't do it. Comparing those two builds, I like the one without the 1nF. I feel my swell a bit grittier and yes, it's distorted when the trigger is all up. However, I like it. 

NOTE: Iíve seen Peter did connect the trimmer with a resistor. Below is the value and explanation of how you should wire the JFET control. Use your ear to set the trimmer based on your liking for the swell.

Hopefully, this post is helpful as I am hoping to see the MBP Bumblebee rolls out soon.