Sunday, 12 July 2020
DOD 210 FET Preamp
Surprised this one hasn't been done. A nice small and quick build, and should have lots of boost on tap and fatten up your tone nicely. Could be a good platform to mod to taste. Seems to be on the rare side to boot. Only video I could find was a DIY build that has some mods, but you get the idea.
Vol2 to output?
ReplyDeleteCongrats on the doctoring too - been at it since '98 myself :)
Have you created any original pedals, out of interest?
And thanks for all the effort you've put into the layouts!
Adam
Seems there are several docs around, making pedals! Finished residency in '95. Maybe 3 more years of doctoring, then hanging it up. I'll have more time to build pedals! And amps...and guitars...roast coffee, and just do *stuff*!
DeleteYes Volume 2 to output, I’ll fix the layout. And yes, I’ve got a few original pedals I’ve done.
DeleteIve started an amp build, hacked together a few guitars at home, but yet to roast my own coffee - gotta try that sometime!
DeleteZach - any chance of layouts for your own designs? Would be very interested to try building one.
Cheers
Verified!
ReplyDeleteBuilt it with J112, 2n5457, 2n5458, 2sk30 (watch pins), and 2sk117 (watch the pins again). The k117 ismy favorite.
The 2n5458 provides a nice overdriven sound when your guitar volume is half to all the way up, though depending on how hot the pickup is, it can get a little farty. If you want a nice boosted sound, the 2sk117 provides a dirt boost that's pretty nice. Also the tone boost is excellent!
Hi I would try with BF245 and BF256 the only "real Fairchild" I can get in TO92 and also because i've ran out of my batch of MMBFJ201 in SOT23. What do you think about? I'm a bass player and found these FET sounds not to bad in bass related circuits!
DeleteCan it be overdriven by itself?
DeleteVerified.
ReplyDeleteI've used this is a small boost in a few pedals so far. Super easy. I leave out the pot and volume 1, instead using volume 3 as an output into another board. Had J113s so I stuck with that.
ReplyDeleteThanks for a great site! A quick question: If building this as an optional final gain stage for a treble boost/overdrive hybrid, can I leave out the 3.9M resistor?
ReplyDeleteI'm completely new to guitar pedal building, and I was wondering if you could help answer a few questions!
ReplyDeleteFirst, what's the dsg? Is there a more formal name for this when I buy parts?
Also, if I were to add an LED and a footswitch, where would I add this?
I'm completely new to circuitry, and would greatly appreciate the advice!
D, S and G refer to the Pins of the FET Q1, which are Drain, Source and Gate respectively.
DeleteFor LED and Footswitch layouts, check the 'Offboard' section of this website.
Good Luck!
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ReplyDeleteverified with J202. Crisp boost that gets dirty. And LOUD! Thanks for all the great layouts!
ReplyDeleteNice simple build. I am only puzzled with bottom brake strip on 5th row. Why is this brake strip necessary if you do not have anything connected on another side of the same strip.
ReplyDeleteNice simple build. I am only confused with a bottom strip brake (2nd strip from bottom). Why is this necessary when there is nothing on other side of the strip?
ReplyDeleteI guess you're right, that cut is pointless.
DeleteI'd say to use the free holes between the two last two stripes (9v and ground) to insert at least a 47uF cap to filter power supply noise, and in case, a polarity protection diode.
While it's not my layout and the cut is pointless in terms of isolating the track so it can be used for something else, I've done this a lot in my layouts to minimise the size of the 9V track. The supply will be the biggest source of noise in the pedal and so keeping it to a minimum, and especially if it means you can prevent it running next to a track near the output for instance, has the potential to be helpful.
DeleteThe 47u is a good shout though, although personally I'd put it below the 220K where there is lots of room to either side
It's been a while I design my layout, too, and to make some tracks shorter or isolated is one of the thing I tried to do sometime, but more than else with signal track. I try to don't make certain track pass too close (typical example: input and output). I still didn't know that the lenght of the 9v track can make noise, I'm not sure I noticed that beafore or I never got any problem with it.
DeleteThanks!
Any chance of a tagboard layout? Please?
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ReplyDeleteThe layout won't work. All the players who built it could hear the sound, and it's because the input connected directly to the output. The input of FETamp should be connected to the gate pin of the transistor.
ReplyDeleteThe input is connected to the gate, via the 220K resistor. It looks like a classic FET gain stage to me. As it says in the layout, just watch the pinouts of the JFET you use.
DeleteSorry, I didn't see that there was the red dot for drilling the pad.
DeleteI would like to build this. Does anyone have a sense for which of the listed jfet's is the least gainy?
DeleteCan it be used a preamp for IR loader? does it sounds good with revv g3? here's my signal chain plan. IR Loader < diy preamp < diy revv g3 < diy precision drive < noiegate < guitar
ReplyDelete