JSA Effects

11 transistors - 8 JFET's and 3 PNP; that's what it takes to rebuild the legendary Klon Centaur with Boss style discrete op amps (the IC in this is an 18v charge pump)

Another "Horse Whisperer" - my discrete op amp reimagining of the legendary Klon Centaur. This time, with a new fancy 'glitter' finish which is mega sparkly irl

You use your altoids tin to hold plectrums. I use mine as an always on buffer with an additional bass control. We are not the same

A wall of smiles

a woman in a suit and polka dot shirt is standing in front of a sign that says `` that 's me '' . ALT: a woman in a suit and polka dot shirt is standing in front of a sign that says `` that 's me '' .

Yay the Leslie Knope gif is back!!!

New tin build; this cheeky two-in-one combines a Bluesbreaker style circuit with a SSS Dumble style preamp for ultimate John Mayer toanz

This was a mega fun build. My "Sustainrrr" - a reworked Elk Superfuzz Sustainer - built with vintage accurate components, and with a 90's Grunge aesthetic

Get Muff; Play Muff; Win!

Big fuzz pedal = even bigger riffs. A very special one off germanium fuzz, built around a pair of 'spam can' NKT transistors and a slew of other vintage components (mostly harvested from some incredibly old Pye radios)

"Hen's Teeth TS" overdrive pedal doing some sweet higher gain tones. This thing is packed to the brim with magic unicorn hair and unobtainium mojo

Here's another clip of this extra special "Hot Toddy" discrete op amp overdrive pedal, this time set for higher gain

The "Hot Toddy" is my flagship discrete op amp transparent overdrive pedal. This particular version is an extra special one made for the Leeds Pedal Show 2026 raffle

As part of the continued celebrations for the 10th anniversary of JSA Effects, I've built an extra special "Horse Whisperer" - my infamous discrete op amp Klon - in an Ernie Ball/John Mayer "Silver Slinky" tin. It's available right now on my Reverb store for less than you'd think 😉

I built a tube screamer pedal with the rarest of the rarest parts, including a vintage TL4558P, MA150 diodes, and blue 'orange drop' capacitors (that's right; orange drops, but they're blue in colour! 😮) and a whole heap of other cool things. It sounds like this - "Hen's Teeth TS"

I was lucky enough to grab an original Boss OD-1 last year and almost instantly fell in love with it. However, true to form, I had some ideas to mod it, and rather than modify a collectors pedal, I built one from scratch with vintage parts. It sounds awesome 👌

How do you make one of the rarest production pedals even more fancy? By building it with a rare of era accurate and vintage components

Is it green? Is it purple? Is it gruple!?! Who knows! All you need to know is that it sounds incredible and is part of a very special batch for early next year (also the makers on the knobs glow in the dark)

This cheeky little fly rig did its job perfectly last week. The "Secret Sauce" is a super secret custom two-in-one that does exactly what it says on the tin

Given the upcoming tariffs and whatnot, rather than wait until the end of the year, I'm gonna drop my "Shelf of Forgotten Pedals Sale" this week so that Americans can also get in on the action before everything basically doubles in price for them

Test build for a small batch of extra fancy drives coming early next year

Long evening organising parts for a special batch of pedals

Porta-studio-in-a-box pedal? I've been building them for over a year, and they sound like this

Something extra cheeky; this is my "Little Treble Maker" with a twist - a buffered bypass. "But Simon, buffered bypass guitar pedals suck!?" I assure you this one not only doesn't suck, it makes everything sound fuller and clearer. This is now the perfect tone maximiser

Cheeky two-in-one; germanium fuzz face with external bias control and vintage spec Tube Screamer with SRV mods. This is an absolute beast and nails Eric Johnson tones

A custom "Horse Whisperer" - my discrete op amp reimagining of the legendary Klon "Centaur". This particular version also has a switchable buffered bypass and battery snap

It's been a long time since I built one of these; the "Horse Whisperer" is a discrete op amp reimagining of the legendary Klon Centaur

As tenet 1 of the Tone Mantra clearly states; "Acquire more pedals, achieve true happiness"

RF Potts is an electronics shop in sunny ol' Derby, and is nearly 100 years old! Because it's so close to Rolls Royce, over the years, they have acquired huge amounts of spare parts from them. This means when you go diving through their old stock, you find genuine treasure

Semi-vintage nonsense today. A Mk 1.5 Zendrive, by which I mean a 1:1 original Zendrive, but with the 'correct' tapers for the voice and gain pots, updated op amp, and the input stage from the Nobels ODR-1 added