Drebbel Pre/eq

Mentaltossflycoon

Well-known member
Build Rating
5.00 star(s)
I hadn't heard of this "inspired by" which always feels weird. No matter how big a nerd I become, there's somehow always new stuff to discover. This drew me in, not so much because of the hype or rarity but the controls seemed like a nice companion to my Nobelium. I also removed my equilux to make room for the nobelium so my only eq has been the nobelium itself. This has been plenty so far but it's always nice to have a little more and there are a lot of ways to nudge your frequencies around here. It really does sound good. Another shockingly low parts count banger.

When reading up on the circuit I saw someone say that they appreciated that you can set this pre to sound just like the bypass signal and then sculpt from there. I think that's a good way to approach this pedal. The boost is kind of crazy loud. I would've considered wiring it to a stomp switch but the difference is just too great. The bass switch is useful, not overwhelming. I can see why this circuit gets so much love. Clean bassy goodness.
Screenshot_20240309_221957_Gallery.jpg Screenshot_20240309_222017_Gallery.jpg
It's such a new project to pedalpcb, I figured it should go in one of the new tayda blue sparkle enclosures. I really hope they expand on these offerings because both the blue and purple are beautiful.
Screenshot_20240309_222029_Gallery.jpg
 
I think you may be the first to post a build report of this thing.


LOVE the graphic!


As for wiring the boost to a stomper...

I've notched out a GPCB 2KnobJob board to fit it onto a 4PDT. Then you can add another volume knob and flip the switch all in one go.

96e194c5-755c-4d9c-bafc-5c14fb7dbe33-jpeg.32508
 
Submarine art has me cheesin'. I'd step on that.

Been looking for a simple bass preamp and this one has me curious. Is the Body pot for mids? Did you do anything special to select the FETs or just snag two and run with them? I noticed the build doc has the specs of them measured.

also... my wallet is gonna hate you now that I know that there is a Metallic Candy Purple option at Tayda...
 
Submarine art has me cheesin'. I'd step on that.

Been looking for a simple bass preamp and this one has me curious. Is the Body pot for mids? Did you do anything special to select the FETs or just snag two and run with them? I noticed the build doc has the specs of them measured.

also... my wallet is gonna hate you now that I know that there is a Metallic Candy Purple option at Tayda...
I did test my jfets on a tc-1.
 
Submarine art has me cheesin'. I'd step on that.

Been looking for a simple bass preamp and this one has me curious. Is the Body pot for mids? Did you do anything special to select the FETs or just snag two and run with them? I noticed the build doc has the specs of them measured.

also... my wallet is gonna hate you now that I know that there is a Metallic Candy Purple option at Tayda...
Forgot to answer your body pot question. Yes, tone seems to tame highs and body adjusts the mids.

Edit: here's some more useful information. Screenshot_20240311_192330_Samsung Notes.jpg

Here you can see where the body knob is neutral, a bit past 2:00.
Screenshot_20240311_194054_Chrome.jpg
 
Last edited:
If you look at the schematic, you can boil the EQ down to a Muff tone-stack.
Albeit it's heavily modded/configurable, but a Muff-based LPF/HPF tone-control nonetheless.



WHAT I WANT TO KNOW IS...

What is "Lead" in the "Left MT" column?
&
What is "Rhythm" in the "UB" column?


The correct options for each would/should/could be:
600Hz, Flat, Sub — NOT "Lead",
&
SUB, UltraBASS — NOT "Rhythm",
respectively.





PS: BTW, I've looked into this "Lead" & "Rhythm" conundrum, and it is never really mentioned, save a vague recollection of one rare occasion it was noted, but its answer has not been addressed, ever.
 
Last edited:
Further thoughts. I went through and tried all those suggested settings and it is definitely hard to get a bad sound. I likely won't look at that chart ever again but it was interesting to hear some of the intended toans.

Those who are playing a nobelium and find the the low end roll off useful but perhaps too much, the Drebbel placed before it can boost the "good" frequencies and get a much happier medium between the two. I'm really really liking how this preamp combination sounds with my array of dirt too.
 
Back
Top