DIY Bass Preamp?

Discussion in 'Burnt Fingers DIY Effects' started by Mark the Moose, Oct 1, 2020.

  1. Mark the Moose

    Mark the Moose Tele-Holic

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    I’m looking to build a bass preamp pedal but not finding schematics for any of the common standard pedals like the sansamp, tone hammer, or any of the VT options. All I found was the Sadowsky...is it any good? Anyone have something different along with a schematic?
     
  2. Norris Vulcan

    Norris Vulcan Tele-Afflicted

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    Try Tagboard FX:

    [​IMG]

    [​IMG]
     
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  3. Mark the Moose

    Mark the Moose Tele-Holic

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    These circuits are BEASTS! I have a Joyo American Sound, which I expect is similar to the "Bass" setting on the SansAmp classic...never really considered it as a possible bass preamp. Might give it a shot.''

    The VT is intriguing, I might give that circuit a shot.
     
  4. tubegeek

    tubegeek Friend of Leo's

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    @Mark the Moose

    Almost any guitar effect can be used for bass provided it's not something that's especially tailored or voiced for bass. What I'm getting at is, a bass preamp and a guitar preamp have a lot in common. The most likely change you would ever have to make is to be sure any DC blocking caps (coupling caps) were large enough values to go down an octave or so lower than they might be in a guitar design - a VERY simple mod, especially when building from scratch.

    If there are EQs designed in for guitar frequencies, that would require some examination, usually again just some cap substitutions to make them more bass-friendly. That SansAmp clearly has some frequency shaping features with those DIP switch choices, but it already has been designed to change it from bass to guitar or vice versa with that input switch.

    Also: when building single pieces, I find that there's nothing easier and quicker to build and debug than a vero board layout as shown above. They may not be the most extremely compact, but boy is it a timesaver.

    That tagboard effects site is more oriented towards layouts than schematics but in my experience anything they show a layout for, the schematic can be found on another pedal-oriented site. diystompboxes forum is an excellent resource, and there is a schematic archive alongside the forum that is very comprehensive.
     
  5. Mark the Moose

    Mark the Moose Tele-Holic

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    Thanks! I’ve built a few dozen tagboard pedals for guitar, but only recently have need of a direct rig for bass. I was surprised there weren’t more traces available of bass preamp/DIs.

    Since I have the Joyo American, I’m going to start with a Really Cheap Bass Compressor”. It reviews well, is a quick build and I have all the parts. Next I’ll start thinking about a preamp. The Sadowsky is fairly simple, may give that a shot, also considering an EP with a few altered cap values.
     
    Last edited: Oct 2, 2020
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  6. ICTRock

    ICTRock Tele-Afflicted

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    there’s also the darkglass b3k pcb over at pedalpcb if you want further options
     
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  7. GorgeousTones

    GorgeousTones Tele-Meister

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    -Hey there! I know it’s a bit of a late response to your post but I have a lot of experience with this particular topic..
    You’re absolutely right, theres hardly anything available either commercially or project wise for bass pedals. Although I’m playing mostly guitar these days, I know how lopsided the diy world is in favor of electric guitarists.

    The good news is that there have been some fantastic bass eq specific circuits developed in the past 10-15 years. It’s just that the majority of them have only been designed for on-board applications.
    You actually mentioned one of the earliest (its absolutely fantastic too btw!) examples of this, the active on board preamp Sadowski developed for their custom basses. Only a 2-band design they eventually decided to also offer it as a stand alone pedal product because;
    1) People began figuring out Marcus Miller had been using it in his J-Bass.
    2) and the high volume of requests for a configuration of the circuit that would fit the endless number of different bass models people have.

    You also mentioned another one as well.. The Aguilar “Tone Hammer” is another one that was initially on-board only. The Aguilar particularly the “OBP-3” is really flexible and widely used for different styles, basses, etc.. BUT it’s really quite different from the Sadowsky and not just because it features a mid band control!!

    My absolute favorite is the John East design J-retro deluxe.. It can do what the sadowsky and Aguilar can do and way more. I highly recommend you google J. East & research it!!
    I have one configured for a Deluxe Jazz Bass that I’m not using too if you’ve got a J-bass, I’d sell it if you’re interested.

    **Essentially you’ve gotta figure out
    What you’re shooting for sonically?
    A big thunderous slap sound w/increased Lows/Highs and scooped mids ala-Marcus Miller.. Pushed upper mids for punch and clarity on fingerstyle funk lines etc..
    How simple/complex you want it, and how flexible the different features are; Look at the Empress ParaEq (which will work well with guitar and bass) and you’ll begin to see what’s possible!!

    -Once you’ve figured that out, Have a general idea and/or you’ve found an existing design/product you’d like to build and need help. PM me and I’ll either draw up something new or help you recreate something. Or if you’re just unsure about something I can probably help steer you in the right direction. Good Luck!!
     
    Last edited: Oct 14, 2020
  8. Mark the Moose

    Mark the Moose Tele-Holic

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    I’ll check out the J East and see if a schematic can be found. Thanks!
     
  9. Mark the Moose

    Mark the Moose Tele-Holic

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    I did not find a schematic for the J East, but I did find a schematic to a project called the "Canned Yam" which is supposed to be based on the Yamaha Nathan East Signature bass preamp...the NE-1. Like the Sadowsky, a very simple build. Maybe I'll build both and see how they sound.
     
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