Albert Kreuzer onboard FET pre / Submarine

[alex.s]

As I mentioned in a thread in the general section I've been looking for a simple yet effective bass preamp to feed a DI during gigs. I lke the simplicity of the Kreuzer/Submarine and the feedback seems to be positive so will be giving it a go. Didn't find any ready made layouts so I've mocked up my own.

Transistors are J201 or 2N5457 etc. I omitted the second switch and only kept the mids switch. My layout had a 1n to be put in series with the other 1n, unlike the original schematic which shows a 2n2, but after a little toying around with the TSC I preferred the look of the response with 2n for the flat mids position.

Not verified yet but soon to be.



The schematic can be found here: http://www.albertkreuzer.com/pics/el/pre/schem/onboard_sch.gif

[Silver Blues]

Oh my god I'm so stupid  I've been searching for this preamp schematic for I don't know how long and have only found Kreuzer's full-size preamp schem on his site. Obviously I didn't see the rest of his circuits, haha! Thank you so much for this.

[alex.s]

No problem! Built it earlier but very annoyingly out of 4u7 caps, so couldn't test it, but after a revision of the very first layout I made I'm confident this one should be fine.

If you do get a chance to put it together this evening please give us a shout! :)

[rocket88]

awesome alex. any word on if this is verified?

[alex.s]

Sorry mate, just realised I never replied...!

Yes it is verified, works well and sounds surprisingly good on guitar, too! The tone stack is very nicely tuned and is usable at both extremes, going from ooohmpy on one side and treble booster-like jangly at the other. Could be great at the end of some fuzz circuits that can do with a volume boost and a tone control, although going the JFET way might be a bit overkill for that?

Made it as a present for my brother who plays bass but will have to make another one to keep for myself :)

[rocket88]

awesome buddy. going to have to get out this on the build list for sure.

[j-pee]

sadly, the schematic of this circuit has disappeared from the Albert Kreuzer website, even the website doesn't exist...
can it still be found somewhere?

[tracer03]

jeepe wrote

sadly, the schematic of this circuit has disappeared from the Albert Kreuzer website, even the website doesn't exist...

Most of the site is cached at archive.org:
https://web.archive.org/web/20100425064745/http://www.albertkreuzer.com/start.htm

[j-pee]

this is amazing, thank you!! :)

magic:
https://web.archive.org/web/20060511072357fw_/http://www.albertkreuzer.com/pics/el/pre/schem/onboard_sch.gif

I've been trying to find it for so long! :)
I do know archive.org, and I love them, but I never new this website-copy feature of theirs!!
this is beautiful...
something, somebody completely disappeared... after just 8 years or so...
but archive.org saved the entire website...

and once again, the original schematic:

[kragg]

Hi, I just discover this effect yesterday : I am looking for a very subtle overdrive, just adding smooth 2nd harmonics overtones and presence without sounding like a distorsion... Would the SubMarine be a good candidate ?
I am hesitating between this and the Rel Llama, and i will use it with a bass synth (not a guitar), which is sounding abit too thin for my taste...

[j-pee]

hi,

I have just built it...  and LOVE it


EDIT:
like so many people, I suggest, too, NEVER BUY J-FETs on ebay...
it took me some time to acknowledge this

[j-pee]

kragg, hello...

I'm no expert whatsoever.. but...
the thing you might be looking for could be a preamp with a diode! :)

EDIT:
an overdrive :) OD --- as rocket88 clarifies it below

here is also dead astronaut's take at the Sunn 200:

http://guitar-fx-layouts.42897.x6.nabble.com/Fender-Bassman-and-Sunn-200s-preamp-pedals-td25184.html

...

[kragg]

Thank you very much for your suggestions, Jeepe, i will look into it.

The Catalinbread booster seems borrowed from a Jack Orman FET booster I once considered to build... I may look into it again :)

I am also bookmarking the Sunn 200s preamp layout

The Submarine, from what i've read, seems quite transparent, and bass friendly :maybe i should begin with this one, and try adding a clipping diode on a switch afterwards if it sounds too clean.
I am also considering building a Red Llama clone, it seems to be a quite transparent, low gain overdrive, and it is an easy build so it might be worth a try ;)

[rocket88]

If you want a low gain OD for bass build a BJFE Blueberrry OD. I posted it on the main page.

[kragg]

Thank you, Rocket88 : i had never heard about this pedal, now you have got me teased ! ;)

(By the way, what i am after is not an effect where the distorsion is "heard", but something which just make the bass range "fuller", fatter. I had built an EQD Speaker Cranker -and i like it !-, but i wish i could find something a little bit different, tailored for bass and not sounding distorted).

[Alamondm]

how would you go about connecting the volume pot in this layout

[nocentelli]

Alamondm wrote

how would you go about connecting the volume pot in this layout

The connection marked "Output" must be connected to lug 3 of  a volume pot (lug 1 grounded), and the attenuated output taken from lug 2 of the pot. The layout (and original schematic) has a 1M resistor to ground from the 1uF output cap, so I guess you could remove the 1M resistor and replace with a 1M log pot as described above, or double the output cap to 2u2 and just connect the pot in parallel with that resistor to get a similar frequency response.

[Alamondm]

Thank you very much.