The Micro Amp is a classic clean boost circuit first introduced by MXR in the late 70s. It's a great option if you need to stomp on something for solos. Pretty simple op-amp design that should fit nicely in a 1590a.
hey, me again, just made this as well, at first it did not work properly, so i went through tonpad's schem and some others, and managed to see the problem, in your schem from 500kpot legs 1&2 signal going to ground through R 2K7 and C 4.7 in parallel. it SHOULD go to ground in series resistor first and then cup, made that change, and NOW it works wonderful! :] (before the change the pots response was not ok, it turned off in about half way, and the overall level of it was very low.)
Hi! I've made two of your pedals as of now and they work great!(Rat and BMP) great site! Just a quick question on this one: other schematics use a 22M resistor for the pull down resitor. Yours uses a 2.2M. Is it a typo or does it have no impact on the input impedance? Thank you!
Hola construi este efecto.con un tl071 y suena muy distorsionado algún tip ? Utilize todo lo que dice el Lay menos el capacitor de 15 uf puse uno de 22uf , ayuda !
I built it and sounds great, but the volume pot is not working very good. From the minimum value up to about 2 o'clock it does nothing and little after that there's a huge jump in volume (like an on off switch) arround a bit past 3 o'clock. The pot is a 500k linear because I couldn't find a logarithmic one. Could that alone be the problem?
hey, me again, just made this as well, at first it did not work properly, so i went through tonpad's schem and some others, and managed to see the problem, in your schem from 500kpot legs 1&2 signal going to ground through R 2K7 and C 4.7 in parallel. it SHOULD go to ground in series resistor first and then cup, made that change, and NOW it works wonderful! :] (before the change the pots response was not ok, it turned off in about half way, and the overall level of it was very low.)
ReplyDeleteThis comment has been removed by the author.
Deleteis there any chance you can make this change ? :]
ReplyDeleteFixed.
Deleteu the man !! thank you, you can verify :]
Deleteu the man²!! I made this too, perfect! soon i'll take pics and send.
ReplyDeletethank you one more time!
works better if we replace the capacitor 15uf for one of 22uf. I used this on mine.
ReplyDeleteWhat is the function of the 47uF capacitor? In some schematics that I saw, it doesn't appears.
ReplyDeleteThanks!
It's for power filtration. Smoothes out any ripples from your power supply.
DeleteHi!
ReplyDeleteI've made two of your pedals as of now and they work great!(Rat and BMP) great site! Just a quick question on this one: other schematics use a 22M resistor for the pull down resitor. Yours uses a 2.2M. Is it a typo or does it have no impact on the input impedance?
Thank you!
2.2M will work fine. 22M is overkill.
DeleteOK thanks! I'm off to finishing this one and finding which will be next...
DeleteHola construi este efecto.con un tl071 y suena muy distorsionado algún tip ? Utilize todo lo que dice el Lay menos el capacitor de 15 uf puse uno de 22uf , ayuda !
ReplyDeleteuse LM741 ou Tl061
ReplyDeleteIs the 10M resistance value correct? Can it be replaced for less value or would the circuit change somewhat? Thanks
ReplyDeleteIt's biasing the input single. You could probably get away with 1M or 2M though.
DeleteIf you want the size to be closer to 15uf use the 33uf cap in series so that it becomes 16.5uf. I hncustompedal
ReplyDeletever
ReplyDeleteI built it and sounds great, but the volume pot is not working very good. From the minimum value up to about 2 o'clock it does nothing and little after that there's a huge jump in volume (like an on off switch) arround a bit past 3 o'clock. The pot is a 500k linear because I couldn't find a logarithmic one. Could that alone be the problem?
ReplyDeleteYeah, that's why.
DeleteYou need to put a 100k resistor between the leg 1 and 2 of the pot. Thats convert a B500k in A500k
DeleteDoes this really work?
DeleteZaraki1337
Deletehttp://www.pisotones.com/Potes/Potes.htm