PedalPCB Resinite/Mad Professor Amber Overdrive (Gorva C65)

[OD is Glorious]

Build Rating

4.00 star(s)

Essentially this is a very high gain distortion pedal that does sustained fuzz. I can confidently call this a fuzz pedal or a distortion pedal but I would not classify it as an overdrive. Tsk tsk Mad Professor... false advertising. The circuit has too much gain – too much sustain - just not the sort of circuit I would call an overdrive. This circuit brings aggression! I will admit the tone is decent and the circuit produces rich harmonic distortion. It gets dark and low when you want and when you dial clockwise your signal will get highly saturated distortion and compression with seemingly never ending smooth sustain.

No op-amps but it uses six transistors. Some oddball parts but I had everything except the oddball 14K7r. There were some other oddities like a 15n film capacitor and two 2N3919 transistors and the 2N5485. I also was all out of BC550c transistors so I used three BC550b in their place (lower DC gain than c). I used a 125B Enclosure from Gorva Design C65. If you never worked with these, it is a precision made box and it is deep. The Gorva C65 that I used was powder coated in silver sparkle. I applied a traditional waterslide and sprayed the entire pedal with Spraymax 2k clear. settled on these 21mm white knobs from Love My Switches - in one picture you can see what it looks like with gold Davies 1510s... they seemed off to me. I used Lumberg jacks and a hot pink soft click footswitch. I used a 3mm orange led with a clear freznel.

The board is laid out well and I enjoyed the build. If you like distortion and fuzz you should build one.

Notes

1. R23 calls for 14k7 – I found it was easiest yo connect a 10k and a 4k7 in series. (I tented them like this --> /\ )
2. You need a 15n film cap
3. You will need a 2N5485 and two 2N3819 transistors
4. Two 1N4007 diodes – I socketed these and may try others

 

[bluedmc777]

I wouldn’t call it distortion but a fuzz yes. But that’s just me lol. Definitely not an overdrive! I just used a 15k in place of the 14k7’s. Bjorn seems to like that value in his circuits cause they’re in almost every one of them. Perhaps he likes the color scheme. @MichaelW pointed out that circuit is very similar to a muff using Jfets. I should have the Skylight (Sky Blue) finished tomorrow…hopefully it won’t get the better of me this time. The board is really compact.

 

[HamishR]

I really like the Amber OD. Yes it's not really an OD but it does sound good. The 2N3819 transistors are used as diodes so in the last one i built I used BAT41s and they sound similar enough - the pedal sounds great. Bjørn has often used 2N3819s as diodes. It is a very Muff-like circuit I agree. But lower gain than most Muffs, which I prefer.

I was playing my Amber OD recently and it occurred to me that the sound reminded me of the Basic Audio Alter Destiny, which is my favourite Big Muff style pedal. So I put them next to each other and the basic tone was very similar indeed. The main differences are the the Amber sounds like a deluxe version of the Alter Destiny - smoother and creamier. But the Alter Destiny has a lot more range in sounds with a kinda three-band EQ and more variety in gain levels. If you like the Amber Drive you may well like the Alter Destiny.

 

[OD is Glorious]

I wouldn’t call it distortion but a fuzz yes. But that’s just me lol. Definitely not an overdrive! I just used a 15k in place of the 14k7’s. Bjorn seems to like that value in his circuits cause they’re in almost every one of them. Perhaps he likes the color scheme. @MichaelW pointed out that circuit is very similar to a muff using Jfets. I should have the Skylight (Sky Blue) finished tomorrow…hopefully it won’t get the better of me this time. The board is really compact.

I had to erase those 300ohms from What intrigued me is the Snow White circuit MP released. I enjoyed it, and when someone creates such a beautiful pedal/circuit I think they must have created others.

I forgot the gut shot! Just added.

 

[OD is Glorious]

I really like the Amber OD. Yes it's not really an OD but it does sound good. The 2N3819 transistors are used as diodes so in the last one i built I used BAT41s and they sound similar enough - the pedal sounds great. Bjørn has often used 2N3819s as diodes. It is a very Muff-like circuit I agree. But lower gain than most Muffs, which I prefer.

I was playing my Amber OD recently and it occurred to me that the sound reminded me of the Basic Audio Alter Destiny, which is my favourite Big Muff style pedal. So I put them next to each other and the basic tone was very similar indeed. The main differences are the the Amber sounds like a deluxe version of the Alter Destiny - smoother and creamier. But the Alter Destiny has a lot more range in sounds with a kinda three-band EQ and more variety in gain levels. If you like the Amber Drive you may well like the Alter Destiny.

It is certainly smooth. I will check out the AD!

 

[falco_femoralis]

The amber od is one of my favorites. With the gain at 9 o'clock its a super nice fuzzy overdriving Marshall amp kinda sound. The tone gets less distinct as you turn up the gain. It's a big muff with lower value emitter resistors so the signal is much less saturated thru each transistor stage. My favorite setting is both the vol and gain at 9.