Marshall 3005 Preamp

The Marshall 3005 Lead 12 was a mini-stack with a 12 watt solid state head made in England between 1988 and 1991. People claim it's a great amp and can get vintage Marshall sounds from it, and that it takes overdrives really well.

One note in the amp the preamp was powered by +16V/-16V so you'll want to build a bipolar power board.

Marshall Plexi 1987x

Next, t Marshall Plexi 1987x.

With a switch to go between channels

With 2 separate inputs like the amp

With both channels jumpered

Marshall 1992 Super Bass

Next, the Marshall 1992 Super Bass

With a switch to go between channels

With 2 separate inputs like the amp

With both channels jumpered

Marshall JCM800 Super Lead

Next up we have the Marshall JCM800 Super Lead.

With a switch to go between channels

With 2 separate inputs like the amp

With both channels jumpered

Fender Bassman 5F6 Preamp

Alright ladies and gentlemen I finally had some time on my hands to relax and kick out a bunch of new layouts and since a lot of you out there have been playing around with those little Class D amps I thought I would be nice to have some more preamps based on amps we all know and love. First off the amp that gave birth to the likes of Marshall, Laney, Vox, and many others. It's the Fender Bassman 5F6. If you are unaware this is the amp that has essentially been copied and modified by every amp company.

With a switch to go between channels

With 2 separate inputs like the amp

With both channels jumpered

Laney Supergroup 100 MkI Preamp

Laney Supergroup 100 MkI

What can I say about the Laney Supergroup. The supergroup was based on the same Fender Bassman architecture just like the Marshall JCM800, Sunn Model T, Mesa Dual Rectifier, and a whole host of other legendary Rock, Hard Rock, and Metal amplifiers. One of the best descriptions I've ever heard of the Supergroup is that it's like a Marshall JCM800 with more balls and gain. It's just an all around badass heavy amp. And for all my lovers of tall things heavy it was used by the legendary Tony Iommi for years, and Laney even went through the trouble of recreating it to reissue it as a special signature amp for Iommi.

Both Channels with a selector switch

Separate Inputs

Both Channels running together (jumping channels)

Treble Channel

Bass Channel

Diezel VH4

"Unlike traditional overdrive stomp boxes, the VH4 Pedal is a true preamp which delivers an authentic representation of its namesake – real Diezel tone – not emulated, not modeled, but sincerely reproduced. The entire signal architecture is faithful to the original: Bass, Mid, Treble and variable Deep and Presence controls allow you to tailor the uniquely Diezel Overdrive character. The command found in the Gain control gives a player everything they will ever need with lower gain settings producing the classic Diezel sparkle and chime to saturated mid-gain sounds, to scorching Diezel leads by cranking it all the way up.

As close to the original VH4 preamp, the VH4 pedal can be used as either an overdrive or as a standalone preamp to feed into your amps power section. What players take away by going direct into the power amp is all the dynamic, unfiltered Diezel tone by simply plugging into your amplifiers clean channel. Two outputs are provided with the first intended to connect to the front of a guitar amplifier and the second allows for a connection to a line-level power amp or power section of your amp via the Effects Return."
Original FSB thread and schematic available here.
This is a buffered effect.
Follow the layout's footswitch wiring.

Barcus Berry 3000A Buffer Preamp EQ

I know, I know. Another day another layout from me. I mean Jez, can't I let one of the other guys post a new layout for once this month? You guys must be sick of seeing my name pop up with a new layout... Anyways, this time I decided to do something different the the massive amounts of fuzzes I've been doing.

I've seen a few posts in the requests over the years for people looking for a preamp for Piezo pickups. The Barcus Berry 3000A is designed to work for acoustic piezo pickups but is also a buffer, preamp, and EQ. This is the only info that I could find on it:

The Barcus Berry 3000AE Piezo Buffer Preamp with EQ is specifically designed to work with all Barcus-Berry electret microphone systems. Features external bass, treble and volume frequency controls to allow a wide range of adjustment. Includes a belt clip for unrestricted movement.

 Barcus Berry 3000AE Piezo Buffer Preamp Features: 

• Designed to work with all Barcus-Berry electret condenser mic systems.
• Features external bass, treble and volume frequency controls for a wide range of adjustment.
 Barcus Berry 3000A Product Specifications:
Input (EQ) Flat
Input Interface: RCA unbalanced
Input Impedance: 2.2 Meg Ohms
Maximum Input Level: 2.0 vrms
Output (EQ Flat, Volume Max)
Interface: 1/4" unbalanced
Impedance: 2K Ohms
THD: .008% @ 1kHz
Noise: -92dBu
S/N: 100dB
Bass: +/- 12dB @ 50Hz
Treble: +/- 12dB @ 10kHz
Frequency Response: 5 Hz - 30kHz (+/- 1 dB) Power Supply

From what I see from the schematic I have no question that it will work with any Piezo pickup, as there doesn't seem to be anything really special to tell me it can only work with theirs. Mostly it's just marketing to get you to buy their pickup.

Orange AD200b MkIII (On Hold)

Up next in the tube preamp series, I give you the Orange AD200B MkIII. This is the current production AD200B, which has a few changes compared to the MkI, which is why I figured it would be a good idea to make a layout for this version as well. Similar to the MkI, the MkIII is known for great clean, with a focused midrange, but has great grit with the gain cranked.

Unlike the Sunn Model T, this has not been breadboarded and tested out, I just followed the same concepts Ciaran and I used to convert the Model T preamp to use FETs. This means at this point, there may need to be some tweaking to component values to get it just right.

Edit: Putting this on hold until i can get some time to breadboard it and get it sounding right.

Orange AD200b MkI (On Hold)

Up next in the tube preamp series, I give you the Orange AD200B MkI. Made in very limited numbers, only a few hundred if that, in 2001 these were made P2P on turretboard. Known for great clean, with a focused midrange, but has great grit with the gain cranked.

Unlike the Sunn Model T, this has not been breadboarded and tested out, I just followed the same concepts Ciaran and I used to convert the Model T preamp to use FETs. This means at this point, there may need to be some tweaking to component values to get it just right.

One thing to note, as I didn't put it in the build notes. All the pots are dual gang pots, with each corresponding lug connected. What this means is lugs 1a & 1b are connected together, 2a &2b are connected together, and 3a & 3b are connected together.

Edit: Putting this on hold until i can get some time to breadboard it and get it sounding right.

Sunn Model T (1st Gen) Preamp

For those that don't know I'm a huge lover of low end, and a worshiper of all things Sunn, in fact I've designed a turretboard layout to build a 1st Gen Sunn Model T ready to go as soon as I have the time to build it, which since I'm getting my Doctorate won't be for 3yrs.

But, I digress. With all these new FET amp in a box pedals out now, I've yet to see any that are based on the amps I've lusted after. So, with the help of Ciaran, who did the majority of the grunt work, I bring you the first in what will be a series of amp preamps converted to FET pedals that he and I are going to be working on.

Unlike, the Earthquaker Acapulco Gold, which falsely claims to emulate the Model T, this monster is a true Model T preamp, minus the presence pot. You get both the Normal and Bright channels, as well as the ability to jumper both together just like the real deal.

The 1st gen Model T was based on the old Fender Bassman, but has much more low end, and nice tight focused grit. It's never truely clean. Now the real magic happens when you put the right booster in front of it, or a fuzz/distortion pedal like a rat or big muff.

Example of someone just messing around, low gains too. :)

Example of one Hovercraft did a tube job on with a Catalinbread Manx Logathian (BMP Variant)

Example of the amp with Distortion Pedals

For those curious what the peamp itself sounds like as opposed to the original amp, here's a really short video of this preamp in a home built 100watt solid state mini model t I built. The preamp is being run at 24V, and both channels simultaneously, so there's no switch between channels. The gain for both channels at noon, master volume at like 2 o'clock, then used a modded Ross distortion I make that's heavily modified for more low end, and an active Bandaxall tone stack. I ran it through my Ampeg SVT210AV (2x10 bass cab), and audio & video from my iPhone. I'm playing my Les Paul tuned to C-Standard with a Seymour Duncan Pearly Gates in the neck and JB in the bridge, but using the neck pickup only.Ignore the crappy playing I'm a bassist not a guitarist.

Layout 1:

Layout 1 Gain Mod: For those that don't want the gain pots to be able to cut off the output completely I've tweaked the layout to match Ciaran's suggestion of adding a 100k resistor to ground from lug 1 of both gain pots. Stupid easy mod if you've already built the regular layout.

Layout 2: 2nd tonestack wiring, exactly as the amp. note that both wiring options will act the same as it's a modified fender/marshall/vox tonestack

Layout 2 Gain Mod: For those that don't want the gain pots to be able to cut off the output completely I've tweaked the layout to match Ciaran's suggestion of adding a 100k resistor to ground from lug 1 of both gain pots. Stupid easy mod if you've already built the regular layout.

Sunn Beta Preamp

This is a single channel version of Sunn Beta Bass & Lead Preamps.
You can find the original FSB thread here.
There are two different sets of caps depending on which version you want to build.

You could use Mark's Bipolar Voltage Converter if you want:
http://tagboardeffects.blogspot.fr/2014/01/bipolar-voltage-converter.html

You could also use this external board to wire a Bass/Lead Switch instead of using fixed caps:

(20/H, 19/C, 22/J.. are board's points coordinates where C1-4 should be placed)

If you want to build the original A/B Channels version just build 2 identical circuits and connect their outputs to the daughterboad below

HPF Technology HPF-Pre 2

I've had a few folks asking for active bass cutter circuit for couple of different uses. First, a lot of stoner rock enthusiast want to split their signal for two amps and some blues folks want to do that too. And since in cases like these, the second amp is usually a guitar amp, which will perform in a happier manner if we don't feed them the lowest frequencies. I got tipped off with HPF Technology's HPF-Pre 2. Even though the main aim for the design is to address issues with double basses, the circuit will work great on other applications as well. This design is open and for mainly that reason, i strongly recommend getting an original unit if you find use for this circuit. The price is more than just right, so your savings won't be much by building one. So. If you can, please support the orginal design.

I built one already to see if the board works with J201s and 2N3906. It does. The frequency pot should definitely be dual gang logarithmic taper.

A quick overview from the author:
HPF-Pre is a preamp with adjustable high pass filter and phase switch for use with piezoelectric pickups on the double bass. It is intended to address the primary issues faced by bassists when playing through mainstream amps and PA systems. Foremost, HPF-Pre is a preamp. Its high input impedance ensures proper buffering of the signal from piezo pickups. It is battery powered and housed in a tough plastic enclosure with internal shielding. An adjustable high pass filter tunes out the subharmonic “thump” generated by the plucked bass, which otherwise can drive ported bass speakers to over-excursion. It is also a useful tool for coping with adverse acoustical environments and PA systems with excessive subwoofer support. A phase (polarity reversal) switch is provided to help control feedback problems. It could also help when setting up systems with multiple pickups, or a pickup and a microphone. Series 2 of the preamp adds an output volume control and an LED battery status indicator. The volume control is handy when your stage setup requires your amp to be out of arm's reach. HPF-Pre is an "open" design. I sell the HPF-Pre at a modest price from my part-time home business. Otherwise, you are welcome to build your own.

Check the site and get the original from https://sites.google.com/site/hpftechllc/home

Blade VSC Preamp, modified

Ran into a schematic of a preamp on-board circuit found in Blade brand guitars. The original called for LM4580 dual opamp, other channel unused. So i drew this layout for a single channel chip and added volume control, power filtering etc. You could try on a number of single opamps to see which sounds best to you. I'd also suggest trying linear taper for volume control. Should make a nice mids booster or a simple box that'll fatten your tone.

A Pair o' Preamps - Echoplex and Tillman

Just a couple of little preamps that have been requested.  Some people swear by these little circuits and use them at the input of other effects because they like the way they colour the sound, so a quick build for people to experiment with.

A couple o' variations:

EchoPlex Preamp with charge pump for 18V from a 9V supply

Early version EP3 with volume control

Tillman with Gain Switch

Acoustic Piezo Preamp

Request for a simple opamp piezo preamp based on this circuit:
http://www.eleccircuit.com/acoustic-guitar-pickup-circuit-using-tl071

Jerry Garcia Tiger Preamp

Request. Info about Jerry's original guitar with inbuilt electronics

Tiger was Jerry Garcia's main guitar from 1979 to 1989. It was built by Sonoma County luthier Doug Irwin. The Tiger is named after the tiger inlaid on the preamp cover located on the guitar's top, just behind the tailpiece.

The electronics of Garcia's Irwin guitars are unique, and feature an onboard preamp and effects loop. Much like a Stratocaster, the three pickups are selected with a five-way switch. Signal from the pickups passes through the tone controls, followed by an op-amp based buffer preamp, or Unity Gain Buffer, which is designed to prevent signal loss due to capacitance when long cables are used.

Tronographic Rusty Box

After a request John K has said that he's happy to have his layouts posted on the main site so there will be a few of these showing up over the next few days.  All layouts posted are verified by John and others in many cases so you can definitely build with confidence.  Starting with the Tronographic Rusty Box:

Info from the manufacturer about the original:

The rusty box is a pre-amp effect pedal optimized for bass guitar. The controls on the rusty box include input gain, bass, middle and treble eq, master volume and a boost footswitch. The rusty box is true bypass and has a balanced output for use as a direct box.

DOD Studio Bifet Preamp / 410

Without the pseudo-balanced output and adapted to work as a stompbox. Not really sure if this is worth a build as it is supposed to be not that loud. Simple design with low parts count, so it might be nice thing to experiment on... The pot tapers are not mentioned on the schematic i found, but i suspect that linear should work well enough for both.

Sadowsky Preamp

Request, and unusually for the site, this layout has been done by our very own Geiri who asked to post it here so everyone can share it, so thanks Geiri! :o)

Info about the original:

The Sadowsky Outboard Bass Preamp/DI Pedal contains the same famous circuitry built into every Sadowsky bass. Housed in a small footpedal box for use on the floor, it measures just 4.5" x 4.5" x 2.25" and weighs 1.5 pounds. Just plug your bass into the box and then go from the box to your amp, and/or direct to the board.

Controls consist of volume, treble boost and bass boost. The Preamp/DI Pedal is perfect for vintage basses where installation of an onboard preamp would affect the instrument's original condition and resale value. The Preamp/DI pedal is recommended for all passive basses, basses with active pickups, and instruments that have active electronics that can be bypassed. It also works great with all upright bass pickups.