Haunting Mids Reflection

The goal of this project was to build three Haunting Mids, keep one and sell the other two, hopefully coming out ahead!

This post covers the original Haunting Mids Fuzz. Note! This is not the JHS pedal with the same name.

What is Haunting Mids?

Haunting Mids is a Big Muff variant. Besides careful choice of resistors, capacitors, and diodes the biggest change to the circuit is dropping the tone stack and the output buffer. This offers the sound of a Big Muff but with more hair and volume. It’s really loud. You hear the raw distortion from from the two clipping sections unfiltered.

In the original the Sustain control is meant to be an internal trim pot, set and forget. With only the volume control on the outside of the box. I decided to put the sustain control on the outside of the box for convenience.

The original is a must have for people who like single knob boxes!

I found this PCB for Haunting Mids while searching for DIY projects on OSH Park.

https://oshpark.com/shared_projects/JtR27cHU

It’s a well laid out PCB for a 1590A sized box. I ordered three of these and built them successfully. This board works well I would recommend it. The switch is mounted to the board which saves trouble wiring.

A little History

The Haunting Mids Fuzz was developed around 2005 by a group of DIY pedal fans who set up a private forum, which I’m guessing was dedicated to the development of the Haunting Mids circuit. I say “guess” because I was never a member though I had heard of the forum.

Not sure when but the Haunting Mids forum died and went away. Go figure, an anti social site is going to have growth issues. That said there is something pleasant about discussions with a small group of like minded individuals rather than everyone and their friends and family.

It seems that Haunting Mids has gone through a couple iterations. The board linked above is labeled v3. You can search Haunting Mids and you’ll find several versions. To my knowledge all versions are based around the Big Muff sans tone and output buffer.

At some point JHS made a commercial pedal with the same name. I’m not sure why they did this. I suspect it was joke, or some sort dig at the original Haunting Mids group, or they just wanted to get a media boost by piggybacking on the name. I wish they hadn’t done this since it makes researching the circuit more difficult.

What’s it sound like?

Sounds like a big muff! It also has its own character like all of the other Big Muff variants, which the world of pedals is full of. But the two cascaded clipping sections guarantees you get the classic Big Muff character. Without the tone stack you hear the clipping section raw and unfiltered! It like a big muff with all the hair and grit.

This demo compares five different DIY Muff variants. Haunting Mids is in the center.

Here’s is another demo of the Haunting Mids:

Build

I built three of these. The parts were were all easy to find. You can get everything at Tayda. I chose to build mine with two knobs and put the Sustain/Gain control on the outside of the box.

I like having the sustain/gain control but the range is not that usable, or maybe there is some less useful range. With the gain up all the way there is too much gain. On reflection I see the reasoning behind making this control an internal set and forget option. I think I might go this route for future builds!

The PCBs from OSH Park are designed for a 1590A enclosure. I decided to build two in 1590B enclosures because I like these better than the small A sized boxes. I did build one in an A sized box.

Costs

This is a pretty cheap box to build. None of the parts are expensive or hard to find. You can source everything from Tayda and order boards from OSH Park.

Ordering the boards from OSH Park requires that you buy three boards but the cost is $14.85 which is about $5 a board. Making the board the most expensive part unless you get a fancy enclosure. The overall cost was about $25 for all the parts to build a single box.

I built three and managed to sell two on Reverb. I kept the last for myself. They sat on Revered for a month or two but eventually sold for $220 (both) not including tax and shipping. Reverb took their cut which left me: $202.50. I spent roughly $75 to build all three so I cleared $127.50.

Haunting Mids project

What’s Haunting Mids?

Haunting Mids is a Big Muff variant. In a nutshell it’s the input buffer, and first two clipping stages from the regular Big Muff circuit. It drops the tone control and the output buffer of the original circuit. There are a few other changes in part values but the the circuit is otherwise the same.

Haunting Mids Fuzz is not to be confused with JHS pedals Haunting Mids which is a completely different circuit that came later.

I created this PCB layout from version 3 of the original Haunting Mids. I made small change by moving the sustain/gain control to the outside of the box. The original circuit used an internal trim pot with only the volume accessible from the outside.

this video compares 5 Big Muff Variants, Haunting Mids in is in the Middle


Another demo of the Haunting Mids



PCBs

The PCB was designed in Eagle PCB. You can order boards from OSH Park for fairly cheap but you must order three. You can order boards here:

https://oshpark.com/shared_projects/Wu8UpzQE

Build

this should be a pretty easy build. Without the tone control and output buffer there are fewer parts than the original Big Muff. Pots and LED are mounted to the board. And most of the off board connections are lined up along the bottom of the board for easy wiring.

The parts are standard and easy to find. You should be able to order all of the parts at Tayda.

Capacitors
C1220n
C2470p
C3150n
C4150n
C5470p
C6470n
C7150n
C8470p
C9470n
C10220n
C1147µ
Pots
VOLUME A100k
SUSTAINA100k
Diodes
D11n4001
D2 LED Red 3MM
D3 LED Red 3MM
D41n4742
D51n4742
D6 LED
Transistors
Q1BC337
Q2BC337
Q3BC337
Resistors
R133k
R282k
R3120r
R4470k
R518k
R61k
R78k2
R856k
R9100r
R10470k
R1110k
R128k2
R1382k
R14120r
R15470k
R1618k
R17RLED


Haunting Mids Fuzz schematic


The circuit shows BC337 transistors but these don’t seem to be so special. You should be able to replace these with just about any NPN device. The usual suspects 2N3904 and 2N5088, or maybe 2N5089 if you want more gain.

The diodes are the same. You can probably experiment with anything for diodes in this circuit. The choices here are interesting definitely try them. But if don’t have these parts or can’t get them use what you have!

Wiring

Haunting Mids Fuzz (clone)

This Haunting Mids clone is on sale on my Reverb shop. If you haven’t heard of Haunting Mids, this is not a clone of the JHS Pedal with the same name, it’s DIY community variant of the Big Muff. It has a great sound and stands on it’s own in the field of BMP clones.

The Haunting Mids Fuzz uses the first three transistor stages of the original circuit but drops the tone stack and output buffer. It also changes up the regular diodes for some more carefully chosen diodes in the clipping stages. What you hear is the raw distortion from the circuit without any filtering.

The original circuit uses a single volume control with an internal trimmer where the Sustain control would go. This was meant to be set and forget. I’ve moved this to outside of the box to give you a little more control and variety of sounds.

Osh Park PCBs

IMG_1158.JPGI just received this order from OSH Park. I order four boards. You are required to buy three copies of each board you order. The cost is $5 per square inch for 2 layer boards (with 3 copies of your board included in that price). Which is not bad, if the boards are small it’s a deal. For example, the SHO was $3.20 for three boards! The Fuzz Factory boards, were $7.75 for three, still a good deal. The Haunting Mids boards were just under $5 each, and the Zeke Bass Distortion was about $8.50 each.

Of course getting boards for designs that people upload with little info can be chancey. There should be more options on the site to comment, and mark boards as verified. Looks like not all projects are shared. User decide to share a project. Hopefully people make an order and test it before sharing.

The quality of the boards is great. A couple things I noticed. There is no solder mask. The pads are gold plated, which is nice. I find the solder mask easier to solder with. Look at the first image. You can see the backside of each of the four boards. Notice the board in the upper right. The pads are fairly small. I think, this is the default pad size in Eagle PCB. It’s not easy to solder, It’s not super difficult either. The two on the left have a more generous pad size. This size makes for a better soldering experience.

I’ll post again when build these boards…

For reference here are some links to the boards I ordered here:

https://oshpark.com/shared_projects/JtR27cHU

https://oshpark.com/shared_projects/xaBILSTV

https://oshpark.com/shared_projects/KE0blXBg

https://oshpark.com/shared_projects/nsJTeQK0

 

IMG_1167.JPG

IMG_1160.JPG

IMG_1159.JPG

IMG_1166.JPGIMG_1161-0.jpg