Voltages at Q1: G=3.72, S=2.99, D=3.0 any sugestion? You can try leaving it out. is it wrong? Hi, for the fat and bright toogle switch ? The legendary echo machine EP-3 pre-amp as designed by Xotic. Thanks! Here's another circuit from Xotic. I've just finished building this. The pot will turn up the volume a bit, but the overall volume (while pot is maxed) is less than unity. Because I put electrolytes of 50V so that I can use 18V DC. I have the boost working, I just can't seem to make the High/Low boost switches to make much of a difference. Built the LPB-1 you have on here and love it. The footswitch you would wire up the way you normally would, and there are a multitude of diagrams for that online. I'm with the same problem... maybe it isn't too noticiable as we expect. "Do I wire 1 switch on row 3 and 1 switch on row 4 so it connects over the trace cuts on column 9?". (in bass boost mode is unlogic cut bass because it was designed for it...) thx!! Thanks you for the tip, but this only reduce a little gain. Fixed....first I put the jumpers, so the gun was probably not ready, that cause bad solder joints. Could it possibly be a problem on the board that I am not noticing? Can it be a linear pot? Just to verify...the red boxes with dods means that you just open the circuit, but you don't place anything? I built it and it sounds awesome! transistor. Thanks!! Really!! Where might the problem lie? Same problem here!! The DIP switches let you choose the boost frequencies, and EQ settings. I think it's there to bleed some treble off. I did see it. The internal DIP switches let you choose the boost level and EQ setting. http://www.generalguitargadgets.com/pdf/ggg_sw_3pdt_tb_dcj.pdf. Hoping you can shed some light on the circuit or something that might be happening. The EP-Booster… I put fresh solder and sounds good.By the way I didnt have 10k pot and I try Tried to replace all wires with shield cable and use the inner part of the cable but still the squeel continues. thanks for reply. It's ok with the other switch on the 15K resistor. so in this design, it will be 3 spst ?1. At the beginning I had an annoying hum too, but happily it was silenced when correctly wiring the potentiometer, 1 and 2 must go to ground while 3 goes to the capacitor of 100uf, mind dont have any output sound. And also ground the effect input whan in bypass: http://diy-layout.com/node/56. Originals have 2SP1815 transistors with BCE pinout, but I've laid this out for the more common 2N5088 with CBE pinout. No one??Pls! tia. This comment has been removed by the author. Any ideas would be so appreciated, Try to place the in- and outpus as far from each other as possible. Hi, Congrats for your amazing blog! Weird that it's not having any affect. Just so I have a point of reference while debugging, which section of the circuit has to do with the high boost? Haha. The EP-Booster is a discrete FET preamp with low impedance output providing up to +20db of unadulterated boost that’s multi-dimensional with shimmering highs and lows. I have the same question? The original EP preamp was designed to run on 18v DC. Hi guys. Fat switch doesn't do anything =\. The DIP switches let you choose the boost frequencies, and EQ settings. Just so long as they're higher than 18v. Now I just can´t hear any difference from the Fat Switch... Hey Arte Na Rede, i have the same hummmmmming problem, how do you solve it?. Please use the contact form to get personal help, or post a topic on http://www.diystompboxes.com/smfforum/ or http://www.freestompboxes.org/ for more help... My build works fine except there is this ear piercing high pitched squeel whether the effect is bypassed or on. You could try experimenting with the values of the fat switch caps. Finished building this today. http://i414.photobucket.com/albums/pp22 ... 11422b.jpg The files are organized by brand. Click here to see the bill-of-materials as a list or download it as a comma separated values file (.csv). We've captured that magic in a new Xotic Effects pedal, the EP Booster. i have already make the veroboard verison but dosnt' work :'(, Hi, how can i reduce the volume boost to 0db I tried to build the above vero layout (my first time using vero), but I'm not getting any signal once the effect is engaged. !but...Fat switch absoultamente not appreciate any change.any ideas??P.S. Again thank you for this extremely good sounding layout. Try 18volts! It's a much better diode for polarity protection than the 4148. I'm having a problem with the circuit. Making them external makes it more versatile in my opinion. Resistors are always 1/4 watt unless otherwise stated. HI, What's the correct dimension do print this board? No idea what the originals use, but that shouldn't effect the tone at all. Thanks for the layout and keep up with the good work on this site. The EP-Booster can be powered by 9-volt up to 18-volts for desired headroom. thanks a lot man..thank you for your layouts.. does it really goes into some overdriven sound when the pots are crank about 12 oclock? I've done, and works well, but the pot doesn't do anything, and I have less than unity gain. The IC (or transistors in this case) are listed in the layout. I really like this site and plan on trying several builds....if I can get this one working, that is! Hey there,I changed 10uf for 1 uf, and nothing.and I changed 100uf by 220uf and neither nothingthanks for reply. Does the switches connect line 3 to line 4 or do they connect the line back to itself? I'm not an electrical engineer by any stretch of the imagination, just a DIY'er who likes drawing layouts. However, once engaged, the LED lights up but there is no sound. I should note, I haven't hooked up the SPDT switches I'm using instead of a DIP. It's not really a big difference but it should be noticeable, especially on higher boost settings (my experience). Works great! Help me, please because it works perfect instead of that. ?!?!?!?! Simple JFET boost with an output buffer borrowed from the Tube Screamer. We’ve captured that magic in the Xotic Effects pedalboard staple, EP Booster. Please help! Here's the schematic for reference:http://i21.photobucket.com/albums/b263/reverweb/EPBc.jpg, Hi !Why do you use a 4001 instead of 1N4148 ?Thanks a lot. This is a library of perfboard and single-sided PCB effect layouts for guitar and bass. Still the squeel. I changed the caps C2, C3, changed the switch, changed Q1, it seems that nothing happens when I switch. Voltages at Q2: E=2.61, C=8.93, B=3.3 (when testing slowly drops to 3.03). Anyway, I wired it according to this : Hi thanks for layout, with which values ​​can I replace the 15 K resistance and the 100uf capacitor to increase the presence of the fat switch and bright? While I'm kinda new to this DIY thing, I follow directions VERY well and its a little disconcerting that this isn't working... maybe its mislabeled? I do get a clean signal thru it when disengaged, so I believe I have the switch wired correctly. i already put a 100k out to act as a volume but its not the same, and i want to keep the 100R impedance at the end. Well, no harder than any other 1590A layout. They should be non-polar MKT's or other film caps. Hey there,I've already assembled and finished.It works well !!! ?Thank you.Keep up the great work man..i really appreciate the effort you put into making this blog. The bright switch bypasses the 15k resistor, and the fat switch adds the 100uF cap in parallel with the 10uF cap at the bottom of the board. i dont have any 3.3nf caps.. whats the purpose pf the 3.3nf? Personally I use 35v or 50v for electrolytics and I think my film caps are rated at least at 100v. All you have to do is download the file and print. boost.is it correct ? I've swapped out 3 different 33k resistors, which all test at almost exactly 33k outside of the circuit... so I know the resistors aren't bad. Using a higher voltage than 9v DC will provide a little more boost and some added clarity with less grain. I'm with the same problem: I didn't ear any change in both switches.I tried another caps, check continuity, and nothing. Project description The legendary echo machine EP-3 pre-amp as designed by Xotic. i am confused in caps the one shade part with (-) is the negative part? Do I wire 1 switch on row 3 and 1 switch on row 4 so it connects over the trace cuts on column 9? I always doublecheck if the cut is 100% using my multimeter. Or - more specific - the 50Hz AC from the power line (EU here)..