Seymour Ducan Pickup Booster

[axeman010]

Anybody heard one of these ?



and the blurb................

By rotating the gain control knob you can add pure, flat-EQ gain, ranging from 6dB to 25dB! The Resonance Switch drops the resonant peak of a single coil pickup up to 5KHz, making a single coil sound like a full and fat humbucker. Features fully discrete Class A circuitry along with true bypass. Comes in a heavy-duty steel chassis and runs on a single 9 volt battery.

I am interested in a couple of things.................

"fully discrete Class A circuitry" - inefficient biased transistor using full input cycle ?

"The Resonance Switch drops the resonant peak of a single coil pickup up to 5KHz" - switched RC Low pass filter cutting out signals above 5KHz?

Would be interested if anybody has a schematic for one of these as I have been asked by a friend to build one. My current idea is a Mosfet Booster with low pass filter. Any ideas / comments welcome !

Regards

Axeman.

[O]

AFAIK, there are no known schematics of this one floating around. The question has come up before, but since the components are surface mount, no one knows what the values are.

You're probably better off building one of the AMZ boosters with a switchable input cap.

(just my 2 pesos)

[DDD]

"fully discrete Class A circuitry"  - just a linear circuitry using BJTs or FETs (IMO advertising trick and nothing more)
"The Resonance Switch drops the resonant peak of a single coil pickup up to 5KHz"  - moving pickup resonance down by adding a simple capacitor on the input terminal. Please note: ONE CAPACITOR from input to ground. Actually a very effective but simple way to change the sound drastically.

[analogguru]

Here is the manual:

http://matsumin.gozaru.jp/contents/effector/duncan_pb/manual.jpg

and inside it looks like this:

http://matsumin.gozaru.jp/contents/effector/duncan_pb/duncan_pb_bunkai.htm

analogguru 

[markm]

I searched the Japanese site high n low the other evening looking for a schem to no avail.
Just curious to see what this booster is.

[zoohr]

Strange
I am building the same thing these days!
It is the amz mosfet booster with "vintagecable simulator" in front.
So far sound promising.
http://goran.tangring.com/index-filer/Pickup-cabletheory.htm

[tcobretti]

I'm not so knowledgeable about surface mount, but it looks like there are 5 transistors in that circuit, which certainly makes it complicated for a booster.

[analogguru]

You always wanted to know what is "fully discrete Class A circuitry" and "The Resonance Switch drops the resonant peak of a single coil pickup up to 5KHz" ?

Really ?

Are you ready to reveal the secret ?

Ok, then let´s go:

Link: Pickup Booster schematic

The other two transistors are only for the LED-signalling - not shown in the schematic

Enjoy,
analogguru

[tcobretti]

The secrets uncovered at last!

That's a pretty funny post analogguru, and thanks for the schem!

[axeman010]

Many thanks Analogguru

Don't know how you managed to track this scheme down, all my surfing produced zip.

I don't know why, maybe its just 'cos I am old but Surface mount boards just leave me cold. Old fashioned boards with big capacitors and proper transistors are a work of art. SM stuff looks like it won't sound any good – weird eh?

This and the previous very interesting posting on vintage cables has given me a fair idea what to aim for in my next build and I think it will be based around the AMZ booster which is a big favourite of mine.

Just out of curiosity I don't suppose you have the component value for the Scheme ?

Many thanks again

Axeman.

[analogguru]

Don’t know how you managed to track this scheme down,...

I traced it from the pictures of the japanese site....

Just out of curiosity I don’t suppose you have the component value for the Scheme ?

for this reason I don´t have the component values....

But it is not a complicated circuit, which could not be "recalculated".

At http://homepage3.nifty.com/ichian/analog/spectrum/boost_freq3.htm you can find the following  frequency plot:



which should be helpfull in doing this.

You can also have a look at the Boss BD-2, MZ-2, OD-2, ODB-3, PW-2, Ibanez DS-10, CR-5 Roland Cube Amp series etc etc....

So to play around here are some starting values (quick assumption with "wet finger", without any calculation) to make the circuit run:

(R1: 2M2)
R2, R3: 1M
R4: 4k7
R5, R8: 10k
R6: 1k2
R7: 22k
R9: 470 E
R10: 100k

P1: 10k neg log

C1: 47n
C2: 100n
(C3: 100p)
C4: 1n
C5: 2n2
C6: 1µ
C7: 100p
C8: 1µ

Q1, Q2: BC 550 C
Q3: BC 560 C

analogguru

[burnt fingers]

My neighbor has one.  It's OK. . I think there are many better boosters in the gallery.  In fact, I built my neighbor a Mosfet booster that I tweeked a little and that pedle was what I was designing against.  I wanted to do what it did but a little better.  He digs my pedal so I guess that's cool. I think there are many better boosters in the gallery.  All the info I got was from this forum so I say, go to the gallery, solder up a sparkle boost, or Jacks mosfet boost, or a mini booster, or a cream pie, or any of the other boosters out there and tweek to your liking.

[newbie builder]

I have one too- there are tons of DIY designs out there that put it to shame, but it's a decent clean boost.

[wokeupfalling]

Hello!

Looking for that SD Pickup Booster schem!  All links are dead    anyone have a copy around?

Thanks!!

[CynicalMan]

From analogguru's site: http://analogguru.an.ohost.de/193/schematics/SeymourDuncan_PickupBooster.gif

[Joe]

Is that the Millenium Bypass that I see?

[WGTP]

Is that a discrete op amp that I see? 

[willqen]

Since none of the links function any longer, perhaps in the future we might think about including the material as an image instead of a link that obviously is only temporary. I too would have liked to study the Seymou Duncan Pickup Booster. Unfortunately that is no longer possible.

Will

[ubersam]

from the wayback machine: http://web.archive.org/web/20131017075653/http://analogguru.an.ohost.de/193/schematics/SeymourDuncan_PickupBooster.gif

[bluebunny]

Welcome, Will.  Images here are links - there's nothing stored at DIYSB except text.  In the meantime, follow Sam's link.