Acti-Boost - Type A and Type R

A nice pair of boosts/tone shapers, both of which can be made using the same PCB (though only one at a time - come on!).

Both versions utilise fantastic Baxandall active EQ circuitry to keep your tone clean and crisp, offering +/- 15db on bass and treble, and both kick out up to 20dB boost.

So, what's the difference?

Type A offers a bit of grit with your boost, pushing into overdrive at the top of the turn.
Type R is clean, clean, clean right up to the top end of the range, where a bit of dirt starts to creep in.

You can also opt for more bass-friendly caps, which change the frequency filtering at the input, and also adjusts the EQ control frequencies. These aren't bass effects, but can be used to great effect on your 4 (or 5)-string.

The kit is supplied with vertical-mount pots which have round shafts, so you'll need set-screw fitting knobs.

If you want the PCB without parts there's a link for that at the bottom of the page.

Partial kit: PCB, all board-mounted components, pots.

Full kit: As above, plus footswitch and appropriate daughterboard/components for your selected bypass type (see Downloads section for details of those), jack sockets, DC socket, battery snap, hook-up wire, LED.

Enclosure (pre-drilled) is available as an option with full kits, and will not take a battery. Knobs are not included.

Builds are only available with full kits including enclosure and vertical-mount pots. Please choose appropriate knobs.

Inspired by: AC Boost / RC Boost

Difficulty: Medium

PCB size: 50 x 50mm

Knobs required: 4

Enclosure: 1590B

Direct-Connect compatible (4-way)

Download INSTRUCTION PDF

Product Code: Acti-Boost

Brand: Pedal Parts

Weight: 130.0g

Product Condition: New

Kit type* Ribbon connector?* Circuit?* Bass-Friendly Caps?* Pre-built? (UK only.)*

£30.00 inc. tax

£25.00 ex. tax

? Tax based on United Kingdom.

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Customer Reviews

7 review(s) posted (write review)

Great boost circuit
"This is a fantastic circuit. I built it a few months ago and haven't turned it off. It stays on as the first pedal on the board with every guitar. I have it set subtly but it always sounds better when it is on. Wonderfully useful EQ. The pleasant surprise is how so many old pedals sound a whole lot better with this turned on ahead of them in the chain." Drew - 22 September 2023

A cloned circuit version of the famed Xotic RC booster
"OK. This pedal got put 1st at the front of my main board once... I turned it on once... It's still on my main board and I haven't turned it off yet because it's a fab clean Pre with usable EQ... I painted it 'Pink' and Need I say more..!" XcLeB - 09 December 2022

Great Booster
"The kit has everything you need in order to build a working booster and the enclosure was very well drilled. Good quality parts (i.e Matsushita and Wima capacitors, JRC4558D and fairly good balanced set of 2N5088). Even potentiometer dust covers were included! The assembly was rather easy and the instructions well documented. I completed it in less than an hour, but given my previous experience I believe that someone with basic soldering skills can do it in about 2 hours. Better check all your solderings, resistor values, diode direction etc before soldering the pots as then nearly is impossible to make changes without desoldering them. I believe that there should be a general population guidance and two actual pictures depending on the AC/RC choice in the manual to further assist beginners, but everything else is clearly stated! My preference was the clean version combined with the charge pumped daugherboard for bigger headroom. The results are more than satisfying!!! A great sounding booster with good tremble/ bass control to further push specific frequencies, gain adds a flavor. Will make your sound cut through without being ridiculously loud!" Dimitrios - 09 November 2017

Nice Pedal!
"Is my firts Fuzzdog kit. Resonable easy to assembly. N 1 diode wass missing in the kit but no problems to find it. Enclosure pre drilled is perfect! This kit (i buy Type A version) is really great sound if search slight to medium (at max) crunch sound. Is very sensityvy to intensity of picking. A very pleasant, balanced and round Grrrrrrrrrrr when you hit hard the strings. Remarkables tone controls. Very nice. Tk." Pesce Giampaolo - 04 October 2016

Acti-Boost R Review
"I built this kit because I was in need of a real good kick for my lead parts when playing live. Wow! I have to say this thing is amazing. It feels solid and it just sounds fantastic. My guitar really cuts through the mix and there is so much boost on tap! The gain delivers quite a punch if I need it to and the EQ is very responsive. This gave me everything I wanted and so much more!" Leigh - 05 May 2016

Perfect kit
"Perfect kit, well thought, well made. The parts are really good, the pcb is easy to solder on, the board mounted pots mare wiring so easy ! Sounds amazing, easy to build, went together like a dream. Can't say enough how happy I am with this boost. Keep in mind you will have to sort the resistors by hand, but the documentation on the website makes it easy and fast." Shirley - 30 August 2015

Cracking build
"My favourite build yet. The boost pushes my amp nicely and the active EQ gives a lovely top end sheen with some nice low end thump." Tom - 17 November 2014