Midboost original "Mont Blanc"
Flexible EQ + Boost Pedal development
A new handbuilt effects pedal for the working guitarist
About three years ago I had the idea to create a versatile, but user-freindly EQ pedal.
EQ is one of the most useful effects for guitar and vintage electric keyboards.
I started researching circuits for EQ and relied heavily on my experience working back in the early-mid 1990s in R&D for SSL (Solid State Logic Ltd https://solidstatelogic.com/ - the mxing console manufacturer).
Quickly I decided I wanted my pedal to be:
- Tough for gigging - I mean I wanted to be able to plug it into teh wrong supply or a reverse supply and it not blow up! I've seen many pieces of gear damaged during huried gig setup this way
- All analogue. Yes I know this is the digital age, AI and all that stuff, and I can design digital circuits, but there's something really nice about old-skool analogue pedals and especially analogue EQ
- Pro quality. Having worked on pro-audio designs in the past I wanted this thing to be suitable for studio use - low noise, repeatable setups, use known levels etc.
- And being pro-quality I wanted to use really good quality components for pots, switches, caps, connectors - without making the thing so expensive no-one would buy it
I decided I should have a parametric EQ, yes I know historically guitarists don't have a good relationship with these, but they are SO useful for tone sculpting it's just people have trouble understanding them. I looked at a few types of EQ circuit and listed to them, finally settling on one. I decided I also wanted a clean boost/cut so I could fix a signal level (too low OR too high) or just provide some boost into an amp input.
I wanted this thing to have as few knows as possible so pretty much ANYONE could understand how to use it (as I said earlier that has been the hurdle with parametric EQs in the past - fine for sound engineers but not so fine for plain old players).
So I made a prototype which was anything but low noise, but it did actually work:
First prototype Midboost Flexible EQ + Boost circuit
Bench testing the first prototype Midboost Flexible EQ + Boost circuit
The first prototype Flexible EQ and Boost sounded pretty good but there were a few things I didn't like
- It had a constant buzz of background noise
- When I stomped on it it made a loud pop (lots of commercial pedals from pretty well-knwon manufacturers do this too I should add)
- The range of frequencies wasn't quite right for guitar
Back on the drawing board I made circuit mods including designing a completely new audio switching circuit using a relay to put the pedal in and out of circuit. I liked using a relay because it meant the pedal could be True Bypass.
The next prototype was built. This time I designed my own printed circuit boards. I fitted all the components myself and hadn assembled the pedal myself.
Here's the new True Bypass Audio Switcher board (I figure I will use this in all future Midboost pedal designs now).
Midboost True Bypass audio switcher board
Midboost EQ pedal audio board
This second prototype pedal went through some extensive bench tests. I won't bore you with all the details but I checked stuff like the signal-to-noise ratio, the frequency response in different modes, the THD, the noise level from the new footswitching circuit etc etc. The sort of stuff we did when I was doing pro-audio.
Probably over the top for a guitar / keyboard pedal but hey I like stuff to be right.
Some specs I measured on the prototypes were:
- Freq response with EQ flat: less than 10Hz to 20kHz +/-0.5dB
- Clean cut/boost: +15dB boost and -15.5dB cut
- EQ/notch centre frequency range:
- Range Lo: 45Hz to 1.8kHz approx
- Range Hi: 240Hz to 10k approx
- EQ max boost/cut: 18dB / -18dB (two of the builds measured more than 18dB range)
- Notch cut (nax): ranged from -38dB to -42dB depending on the build
- Noise (input shorted, gain max): was at least -88dBu(A) on all three prototypes
- Noise from engaging pedal: -50dBu noise from switching a 1kHz 0dBu tone
I was fairly happy with these measurements. Pro-audio would be better tha this for noise and THD but the limitation is only having a 9V low current supply to play with, so component values are a bit restricted.
Then the pedal went out for real testing to a couple of friends in bands for road testing. I built three of these prototype pedals, see some of the road test feeback I got below.
In addition I started using the pedal myself for playing and recording.
Feedback from the 'road test' guitarists for the FEQ-1 pedal
"Absolutely loved the pedal! It’s everything I’ve ever wanted in a eq pedal, the boost in volume works to perfection and even at maximum volume it has a wonderful sparkly tone. I’ve gigged with it now and used it in studio work and it’s been the ultimate tone sculpting machine and has got serious potential in my opinion!
I absolutely love the mid cut at about 1.3k with about +3 db on the low range setting!" -- Josh Merchant, gigging Guitarist and TikTok musician (https://www.tiktok.com/@joshua.kash)
"I'm using it on every song to be honest!! Really like it as a clean boost for a bit of extra volume in solos, also as a mid boost for some other songs. Used it on another song for scooped mids - I liked the different dimension it gave to my distortion pedal" -- Dan Cunniffe, Lead Guitar, Bathtub Dancing
The final production version of the pedal!
Here is the finished pedal, ready for production (that means me I have to make some :) You can see some ideas about how it can be used back on the Shop page.
Midboost FEQ-1 Flexible EQ + Boost pedal
"Can I buy this amazing pedal" Answer is "You will be able to buy this soon!"
(I'm in the process of building these pedals)
If you want to be on a waiting list then drop me a message using the link at the bottom of the Home page