Dunwich Amplification Fuzz Throne Deluxe - Tall box version

 Traced by evilarsen, AlexS and Marco.

evilarsen did the dirty work by building and verifying the board.

 

 

 

...and here is evilarsens build.

 

 

Dunwich Amplification Ye Great Olde One - Fuzz section

 Traced by evilarsen.

This was a small run of a custom pedals for Slomatics. It was essentially a dual pedal with a fuzz circuit and a modulation circuit. This layout is for the fuzz section only.

The modulation section remains unknown. There was two variants; a 4 stage optical phaser and a Parapedal with LFO. Still, you might get close enough using your favorite phaser/wah after this fuzz...

Dunwich DA-120 Overdrive - MOSFET version

 Time for a small break again.

So I think it is time to release beast that I traced with lots of help by evilarsen and built it up a few months ago. It is not a Matamp amp emulator per se, more of a fuzzy overdrive that simulates the sound of a cranked Matamp. It also includes a power amp emulator section and a gyrator boost section at the end of the circuit. Also you can use MAX10044 or ICL7660S for the charge pump if you plan to run it on 9v only which sounds best IMHO.

Dunwich Amplification DA-120 Overdrive V1

 Here is a layout of an early version of D-120 OD. It is basically a J FET conversion of a Matamp GT120 with some interesting tweaks like diodes connected to the sources for some of the transistors. It also have a clean blend /summing amp circuit. The original had fixed resistors across drain and V for Q1 through Q3 but I replaced them with 50k trimpots for easier bias setup.

Note that the more recent revisions is a completely different beast circuit wise with a rotary switch, MOSFET transistors and a quad op amp.

Dunwich Amplification Bass Overdrive (DIY)

 Based on Boss ODB-3 but with lots of added controls and switches!

Schematic and BOM at OSH Park.

Dunwich Amplification Wizard Fuzz - Big box version

 Here is a heavy beast from Dunwich, traced by Vince69 over at FSB.

Dunwich Amplification Apostle (DIY version)

 Schematic and BOM avaiable at OSH Park.

Looks like a very interesting Matamp/Orange amp emulator running mostly at almost 36v with an active speaker simulator(?) and a "Mode" switch for two tonestacks. Each being at different locations in the circuit.

Dunwich Amplification DIY HM2 "2021 Edition"

 Another take by Dunwich Amplification on the mighty HM2 circuit. Just released as a DIY project at OSH Park it has some tweaks all along the circuit compared to the stock Boss schematic. It also has a built in active clean blend circuit and switches for both hard and soft clipping diodes.

Schematic and BOM can be downloaded at OSH Park. 

 

 

...and a layout with "Dope-Ass Lower-Tuned" values for the gyrator eq section requested (?) by MTK.

These values were calculated by Ryan from Heard Sound Circuits and makes things sound....more evil.

(Low: 62,48 Hz, Mid: 716,67 Hz, High: 1065,5 Hz)

 

 

 

 

Demo time with MTK!

 

 

 

 

Dunwich Amplification CTG (DIY version)

 Here we have a "little" monster layout for a DIY project that Dunwich Amplification just released at OSH Park. It is supposed to a emulate a part Al Cisneros of Sleep bass rig. It is basically three circuits in parallell, a DOD 250 Pre Amp, a Boss DS1 and a clean J FET boost with a James tonestack.

Schematic and BOM can be downloaded HERE.

 

 

Dunwich Amplification Olde Dirty Bass - 125b/Custom version

 This one shares almost the same footprint as the earlier "Big Box" version but component values have been changed all across the circuit. No major changes except for the "bass boost" cap/resistor at the Cut switch and a few extra caps and resistors.

Schematic is avaiable at FSB.

 

 

Dunwich Amplification Volt Thrower - Big box version

 A bit hesistant to upload this one since there is an unknown cap value and pot value. But a quite a few people have requested this one so I guess a 95% accurate trace is ok? 

Traced by evilarsen, AlexS and myself. It is a Rat based circuit running on 9v/-9v up to 18v/-18v. It is intended for bass but works equally well for heavy down tuned guitar playing. Tonestack is a passive James variant and there is an extra gain/makeup stage before the output. 

The diode selector rotary switch has a quite interesting configuration. Many of the diodes are stacked and are asymmetric. Probably the keep an even output level across the switching range?

 

Dunwich Amplification Olde Dirty Bass - Big box version

 

 Update 2 210514

Both schematic and layout is now corrected. A big thank you to Vince who traced the later 125b version which revealed how the active Mid control really works.

 

Update 1 210514

Caution! There was a mistake in the trace. The Mid control have a different setup than the schematic and layout below indicates. Do not proceed if you want a Mid control that is 100% identical to the stock ODB. I will update the the schematic and layout as soon as I can. Lesson learned, hesistant to trace from gutshots from now on...

Intended for bass but works really good for guitar as well. Based on OCD but tuned for more low end, headroom and gain. Treble and Bass controls is a passive James tonestack and Mid control is an active Bridged-T feedback control. Cut switch is Shelving filter for the first gain stage and Clip switch selects between assymetric MOSFET/Silicon, LED and none clipping.  Traced by AlexS and fuzzhead and the layout is verified. 

Two things, though. We couldn't figure out the value of the Treble cap in the James tonestack but values between 330pF and 1nF sounds good.

Also, the LTC1144 charge pump is only needed if if you want to run it on 18v to get a 36v swing within the circuit. They are pretty expensive and not that common. MAX1044 and ICL7660S can be used as well but the cut between pin 1 and 8 of IC2 must be omitted. Those charge pumps can only handle a maximum input voltage at 10v and 12v respectively so a 9v power supply/battery is higly recommended...

 

 

 

Dunwich Amplification Modified HM2 - "Left Hand Path" version

 Traced by AlexS and Fuzzhead, this is a quite tweakable and heavily modified HM2 variant with more gain on tap, more volume, two on/off/on diode switches and a very flexible four band eq. 

It is a quite noisy beast when Gain and all eq controls is maxed out though but a buffer up front helps a lot. Or you can increase 1K resistor connecting to Gain 3 to calms things down. Stock HM2 value is 47k so there is a pretty wide margin to experiment within.

Layout is verified.

 

 

 

 

 

Dunwich Amplification Hybrid Cthulhu - 3 knob version

 Another Dunwich trace by evilarsen, AlexS and fuzzhead.

I believe this one was made on custom order and/or was a on/off product. However, compoent values varied over time but we added some notes at the bottom of the layout and schematic for the most significant changes that is worth experimenting with:

Input capacitors connecting to the input cap blend control (Depth) varied quite a bit. I ended up with a 15nF for C2 and an 1uF for C1 with a 100kC Depth control. 

The other thing is one of the clipping diodes at Q4. Most units had a germanium diode but a few had a silicon transistor in TO-18 casing wired as a diode. Both layouts bellow have slots for both components but remember to use one of them, NOT both.

Two layouts, one normal and one with 1.5W carbon comp resistors. Both is verified.

 

 

 

 

 

Dunwich Amplification Modified HM2 - DIY version

 Dunwich released a small run of DIY PCBs a few years ago of a modified HM2. There is a few changes from a stock HM2 most noticable the on/off switches for both soft clipping and hard clipping diodes. You may want to experiment with the cap values at one of the gyrators for a more effective separate Mid control. AMZ and Griffin Effects have very useful bandpass filter/gyrator calculators. 

Dunwich Amplification Fuzz Throne

 There is several versions of this one but the 4-knob version seem to be the most common version. 

Initially, it was a custom fuzz for doom band Conan but it was later slightly modified and morphed into Dunwich/Magic Pedals lineup of pedals. Traced by evilarsen and fuzzhead who both dig the sounds coming out of this doom circuit...

 

 

 

 

 

 

...and here is what evilrsens build looks like.

 

 

 

 

 

 

Dunwich Amplification Cthulhu Fuzz - 1 knob silicon version

 Time for some doom. Recently traced by evilarsen and an odd fella who likes fuzz. Layout is verified.