Is it possible to stick two pre-amps in a pedal and switch between them?

[ForbiddenWytch]

Hey everyone

Recently I've been playing my passive basses a little more but miss the tonal adjustment I can get from my basses that have an Active pre amp in them (not just that but the level of the passive basses is obviously lower than the active ones which makes a difference when hitting my signal chain). As one of them is a Fender Precision bass that has an extremely small control cavity and wouldn't fit a pre amp and battery without additional routing (that's not going to happen either) and the other is a Spector style clone that I added a neck hum bucker to and did the Billy Sheehan style wiring mod to for dual output (the pre amp would only be used on the P/J pick up output) which has left minimal space in the cavity I got to thinking about sticking a pre amp in a box... then realised that I like the sounds of two different pre amps with the two different passive basses I use which got me thinking about sticking TWO pre amps in a pedal enclosure.

My idea is as follows: 

- Enclosure would be either a standard MXR sized or Bass Big Muff sized hammond case (dependent on which would fit all the components)

- 2 internal bass pre amps 

- 2 footswitches: 1 for selecting which pre amp the signal flows through and one for bypassing the pedal altogether (for times that I just want that "passive" sound)

- Both have their own output trim which would be good for matching the level against my "active" basses and not having to worry about it (as the trim pots would both be inside the pedal enclosure)

- 3 status LEDs (One status LED each pre amp and one for pedal status)

- Regular side mounted jacks (likely Switchcraft stereo jacks)

A couple of things I haven't decided on yet are:

- Power supply: Both of them are 9v pre amps so do I run an 18v supply in or would it just be better to run a 9v supply in? (my power bank has both 9v and 18v outputs)

- Layout: Both pre amps have the pots attached to wires so I can mount them in any position but I'm not sure whether to put them Horizontal or Vertical?

 

This is all a theoretical thing and just another idea I have dreamt up in a moment of boredom so it might not actually happen but thought I'd gauge people's thoughts on it. I know there are pre amp boxes out there but none of them do anything remotely similar to what I'm thinking of and are a hell of a lot more expensive than what I could put this together for.

Edited January 26, 2019 by ForbiddenWytch
Details added

[skidder652003]

https://www.gak.co.uk/en/dave-hall-dha-vt2-twin-eq-std-bass-pre-owned-/903303

[Bigwan]

3 hours ago, skidder652003 said:

https://www.gak.co.uk/en/dave-hall-dha-vt2-twin-eq-std-bass-pre-owned-/903303

Did you actually read the original post? 

[ForbiddenWytch]

1 hour ago, Bigwan said:

Did you actually read the original post? 

Thank you for saving me from that reply Bigwan! 

[HazBeen]

Apart from the full bypass this is it. If you rewire the mute to be a bypass aren’t you there?

https://www.thomann.de/gb/providence_dbs_1_dual_bass_station.htm

It is a great clean 2 channel pre. Clearly you could stick 2 onboard preamps in a box, and wire up etc, but this gets you there without much fuss methinks.

Edited January 27, 2019 by HazBeen

[Dad3353]

I think (but could be wrong...) that the OP was thinking of building his box for much less than £215. 

[ForbiddenWytch]

48 minutes ago, HazBeen said:

Apart from the full bypass this is it. If you rewire the mute to be a bypass aren’t you there?

https://www.thomann.de/gb/providence_dbs_1_dual_bass_station.htm

It is a great clean 2 channel pre. Clearly you could stick 2 onboard preamps in a box, and wire up etc, but this gets you there without much fuss methinks.

That does look like a great pre amp and piece of kit but that’s nearly 3x the price I could put the one I’m considering together for. Also the size of it wouldn’t fit on the space on my board. The space I have is the same size as an EHX bass big muff so I’m just going to buy an enclosure.

 

8 minutes ago, Dad3353 said:

I think (but could be wrong...) that the OP was thinking of building his box for much less than £215. 

Hahaha yep, spot on mate! I could do the one I want for £80 (and change). 

[obbm]

Technically I see nothing wrong with the concept. Fitting it all in would be an interesting challenge but not impossible.  It just depends on the size of the components.

As for powering, if both pre-amps are 9-volt then a 9-volt supply would be right.  If the pre-amps are able to run at 18-volts then it would make sense to use an 18-volt supply and give yourself more headroom.

[skidder652003]

19 hours ago, Bigwan said:

Did you actually read the original post? 

I'll repeat as the origional reply was removed, I was only trying to be helpful, there's no need to be a large appendage

Edited January 27, 2019 by skidder652003

[HazBeen]

13 hours ago, ForbiddenWytch said:

That does look like a great pre amp and piece of kit but that’s nearly 3x the price I could put the one I’m considering together for. Also the size of it wouldn’t fit on the space on my board. The space I have is the same size as an EHX bass big muff so I’m just going to buy an enclosure.

 

Hahaha yep, spot on mate! I could do the one I want for £80 (and change). 

Clearly not the preamps I am thinking of.... but Ali and Ebay certainly offer pres that would enable you to keep it sub 80 quid. Let us know how it pans out.

[Jack]

There's DIY kits to take a lot of the work out the design for you. If you actually want an internal preamp that you'd usually find inside a bass, but in a pedal, then what about the many variations of the Stingray preamp? To my mind, a preamp is a preamp no matter where it is, so there's loads of options.

 

Super trivial to have two of them in one enclosure. Keeping with the kit theme, you could even use an A/B kit in the same box as both preamps. Hell, combine it with a mixer kit too! Many ways to skin this cat.

[dannybuoy]

If you're particularly wedded to two certain preamps you want to use, and you fancy getting your hands dirty with some soldering, go for it. If not, I would just try a few existing preamp pedals, find two you like, and switch between them!