My next build will be a one knob clean boost hopefully, not necessarily for gain, just an EP style, always on, tone enhancer thing. Here's My EP layout:
https://4.bp.blogspot.com/-_ltumfwhRb4/U5JdWEcP34I/AAAAAAAAHsc/WJJ0ZTbv_Ks/s1600/Echoplex+EP3+Preamp+-+Early+Version+II.png
Here's an LPB1:
http://2.bp.blogspot.com/_y7gcfRKQFgA/S6VnFIga11I/AAAAAAAAAIY/beERCO9AO_A/s1600/EHX+LPB1.png
Here's a DOD 250:
https://4.bp.blogspot.com/-OGV5td7Xiao/Uepb8pu3nhI/AAAAAAAACeo/YhOzP3rNtL4/s1600/DOD-250-Reissue.png
And an EZ DOD which cuts the number of on board components from 19 down to 15:
http://www.bouron.org.uk/marc/EZ250.GIF
I want to breadboard all three and build whichever I like most.
2 questions:
1. Is the EP layout a valid pedal build or is it missing some stuff, like input stuff to stop the switch making a pop sound or whatever? Or an input capacitor (whatever that is)? It's a basic circuit that was possibly meant to be added to other circuits rather than used on its own. I'm aware that it will probably just get me to unity at full blast, but that's ok for what I want.
2. Does anyone know of a layout/schematic for a one knob clean boost based on a 250? I just want volume or tone shaping with no clipping so the circuit should be pretty small and simple, i would think... I'm probably too much of a noob to figure out how to turn a dod schematic into a clean boost layout but maybe someone could give me some pointers...
Here's a schematic for a DOD: http://beavisaudio.com/schematics/DOD-250-Overdrive-Schematic.htm
What would I omit to turn it into a simplified clean boost? The diodes obviously. Anything else?
Hm, i've not breadboarded anything before. I guess I should be working from schematics, not layouts?
Thanks.
Quote from: Killthepopular on April 27, 2019, 12:06:12 PM
I guess I should be working from schematics, not layouts?
Yes.
BTW, the EZ 250 (my layout, as it happens) is nothing to do with the DOD 250.
Quote from: Killthepopular on April 27, 2019, 12:06:12 PM
2. Does anyone know of a layout/schematic for a one knob clean boost based on a 250?
If you try and make the OD250 into a clean boost you basically end up with the MXR MicroAmp https://www.electrosmash.com/mxr-microamp (https://www.electrosmash.com/mxr-microamp)
I'd recommend trying out an AMZ mosfet boost and a zvex SHO while you're breadboarding. Much more interesting than the LPB-1 in my opinion
http://www.muzique.com/schem/mosfet.htm
http://effectslayouts.blogspot.com/2015/01/zvex-sho-crackle-okay.html
How much boost do you want/need? Is it simply to get optimum S/N and some buffering for retaining top end, or do you also want the capability to "punish" the front end of an amp?
The MOSFet boosts like the AMZ unit and ZVex SHO will certainly brighten up your sound. You can always try a Stratoblaster as well. Indeed, there are a ton of single-FET boosters around.
My one caveat is that if included in your objectives is being able to "punish" the front end of an amp and push it over the edge, you will want some means for dialing back the treble. That could be a panel-mounted treble-cut control, a trimmer inside, or a fixed treble-cut.
Quote from: bluebunny on April 27, 2019, 01:54:49 PM
BTW, the EZ 250 (my layout, as it happens) is nothing to do with the DOD 250.
Oh.
Quote from: slacker on April 27, 2019, 02:14:40 PM
If you try and make the OD250 into a clean boost you basically end up with the MXR MicroAmp https://www.electrosmash.com/mxr-microamp (https://www.electrosmash.com/mxr-microamp)
Ah. That's useful to know. I don't like the sound of the Micro amp (on video demos). I just thought I might like a 250-based boost as I tend to like 250s. I'll probably skip it then.
Quote from: patrick398 on April 27, 2019, 02:47:42 PM
I'd recommend trying out an AMZ mosfet boost and a zvex SHO while you're breadboarding. Much more interesting than the LPB-1 in my opinion
Not heard of the AMZ... I sort of liked the clips of the SHO, seemed kinda gritty in a good way. Maybe I'll try that one too.
Quote from: Mark Hammer on April 27, 2019, 04:36:41 PM
How much boost do you want/need? Is it simply to get optimum S/N and some buffering for retaining top end, or do you also want the capability to "punish" the front end of an amp?
My one caveat is that if included in your objectives is being able to "punish" the front end of an amp and push it over the edge, you will want some means for dialing back the treble. That could be a panel-mounted treble-cut control, a trimmer inside, or a fixed treble-cut.
Nah this isn't really my objective. I like the idea of the EP preamp, just a simple little circuit that makes your tone subtly better in some way. I was just going to make an EP pre at first (i dig the smoothness) but then I realised that I maybe slightly preferred the slightly grubby, warm tones of the LPB1. So I'll make those two, and I'll have a look at some schematics. I'll have another look at the SHO too because it seemed kinda cool. I guess I should try that Tillman one too...
MXR CAE MC-401
Quote from: Killthepopular on April 27, 2019, 05:59:30 PM
Not heard of the AMZ...
AMZ website is definitely one worth bookmarking, there's a butt-load of great info and schematics there to explore. The mosfet boost is a great clean boost for giving your tone a bit of sparkle and clarity (in my opinion and with my setup) but as with all these booster circuits, it depends what guitar and amp your using. Breadboarding is the best way to go :)
Quote from: Killthepopular on April 27, 2019, 05:59:30 PM
Not heard of the AMZ... I sort of liked the clips of the SHO, seemed kinda gritty in a good way. Maybe I'll try that one too.
Jack Orman (the fellow who IS AMZ) has probably been at this sort of thing longer than many of us. Trust him.
Had a quick look at AMZ. Looks like a great resource. Will definitely start skimming through it.
Quote from: Killthepopular on April 27, 2019, 05:59:30 PM
Quote from: bluebunny on April 27, 2019, 01:54:49 PM
BTW, the EZ 250 (my layout, as it happens) is nothing to do with the DOD 250.
Oh.
FYI, this is Joe Davisson's EZ-250 overdrive:
(https://i.imgur.com/F61MUL5.jpg)
And rather good it is too.
Skip the two 1n914s and you probably will get a cleaner boost: it's a lpb1 with a buffer in front. A very smart mod.
You can also remove the clipping diodes from a real dod 250.
I suspect that both solutions would not be completely clean, but maybe they will work for you.
The DOD 250, MXR Distortion+, and similar, use op-amps that will not swing wider than within a volt of each rail, or +/-3.5V. Amplifying a +/-100mv signal more than 35x runs out of headroom, such that what hits the diodes is already clipped, once you've exceeded that amount of gain (and both units have max gains >200x.
I have no idea how wide discrete circuits like this can swing, and what their behaviour is once headroom is exceeded. Suffice to say that lifting those diodes WILL get you clean sound, provided the gain is kept modest.
Hm. One guy says a DOD 250 is the same as a Micro Amp with some extra stuff. Another guy says it's like an LPB1 with some extra stuff.
I'm gonna do the LPB1 because the demos sound cool. I was gonna skip the micro amp because the demos made it sound a bit harsh to my ears. Originally I wanted to make a clean version of the 250 because I liked the 250 and thought it might give me some unique, 250-esque sound. But if it's just gonna end up like a boost I don't want to make (micro amp) or a boost I'm going to make anyway (LPB1) it seems like there isn't much point in me going down the 250 route.
So I'll try out the LPB1, an EP and I'll have a look at the SHO, the Tillman and some AMZ stuff.
If it helps at all, the VFE Distortion3 is effectively a micro amp, 250 and distortion+ in one box. The circuits of the three are very similar with just a few component changes. By making these components switchable you get all three near enough.
Schem: http://vfepedals.com/schematics/distortion3.pdf
The MXR CAE MC-401 is totally clean, and doesn't color the sound at all. My veroboard layout has an additional voltage doubler for mor headroom, a switch for booster or buffer mode (can be omitted for booster mode only), and RG Keens Millenium bypass to use a 2pdt switch instead of a 3pdt:
(https://musikding.rocks/userImages/9d/338-9da5cecf.gif)
↑↑↑ Looks fancy. Nice and clear layout too. But I already checked out the MC401 and whilst I thought it sounded better than the micro amp, I also lumped it in with those other boosts that seem to make things subtly brighter or clearer on top, and I really like the idea of a boost that fattens/mellows slightly, so I think I'll stick with the EP3 and LBP1 circuits. I also checked out some of the other circuits mentioned above (SHO, Tillman, AMZ mosfet) and again found that they made things a bit crisper and clearer which doesn't appeal to me all that much. There was another boost that sounded good to me, the Pigtronix class A boost, but I couldn't see a schematic for that anywhere so I guess I'll skip it.
I got the extra parts I needed for the EP and LBP so I'll get started on them today or tomorrow. My progress will probably be quite sluggish because I'm trying to keep writing lots of songs rather than dedicating large stretches of time to circuit fiddling.
have you looked at version 2 of the beginner project?
https://www.diystompboxes.com/smfforum/index.php?topic=97041.0 (https://www.diystompboxes.com/smfforum/index.php?topic=97041.0)
You seem to make decisions based on hearsay or YouTube videos...
The MC-401 has the most linear frequency response from all the circuits that are mentioned above.
Every booster "brightens" your signal, because it effectively shortens the part of the cable that your pickups "see" - the resulting resonance frequency becomes higher, because only the capacitance of the cable between guitar and booster is part of that equation as long as the booster is active.
Two solutions:
- a capacitor to ground at the input of the booster circuit to simulate the cable capacitance, maybe 100 to 150 pico farads per meter.
- a capacitor to ground safter the opamp, as in the DOD250. Add a pot to turn it into a simple tone control.
An easy to breadboard alternative proposal..
(greetings to Sam.. :icon_wink:)
Gain all down to unity (verified) with as clean as reasonable sound..
(https://i.imgur.com/sgwtp9A.png)
P.S.
C3 value can be reduced to 1μF without tone issues for following impedance down to 10k..
I've built a ton of one knob boosts as my main amp (a 70s HiWatt) really likes them for a kick from crunch to distortion. My absolute favourite (which doesn't seem to get much love elsewhere) is the Seymour Duncan Pickup Booster. It just seems to give a really natural and dynamic boost. I couldn't comment on how much of that is to do with the interatction between the pedal and the specific amp though.
http://tagboardeffects.blogspot.com/2012/12/seymour-duncan-pickup-booster.html (http://tagboardeffects.blogspot.com/2012/12/seymour-duncan-pickup-booster.html)
I've breadboarded the LPB successfully. It has a badass, fat, fuzzy tone when you hit it with a hot signal and gives a thin but clear clean tone when you roll off your guitar volume. It was a bit easier to make it than I expected so I might have a go at some more of the simpler circuits mentioned in this thread, namely the SHO, the stratoblaster and the AMZ mosfet.
On a largely unrelated note, what's the reason why guitars seem to start humming slightly when you roll back the volume? Both my guitars do this. Is it a common phenomena or just something crappy in my setup?
Quote from: Killthepopular on April 27, 2019, 12:06:12 PM
I guess I should be working from schematics, not layouts?
God yes. Don't get stuck in the paint by numbers perf/vero/breadboard rut.
Learning to read simple schems is much easier than it seems and will make life so much easier in the long run. Its also very satisfying to build from a schem. It feels more real if that makes sense.
It just occurred to me that I have always loved what my DS1 does to the feel of my guitar, even when it's set totally clean, so I thought I'd add the DS1 output buffer to my list of circuits to try out. Here's something i cobbled together from the electrosmash page, from the power and the output schematic:
(https://i.postimg.cc/fJ5TF8x7/DS1-out.png) (https://postimg.cc/fJ5TF8x7)
Would this work as a standalone buffer?
Does the circuit make sense? I took R24 and R25 from the power supply bit. It looks like a generic 4.5v divider.
Do i need to get a 2sc2240 or can I just use another transistor? I have these already: J201, 2n5088, bs170, 2n5457.
I've built Fred Briggs' "64 Vintage Vox" circuit, and quite like the tone. It includes gain and limiting controls, but those can easily be internal trimmers, rather than panel-mount pots, keeping only the volume control once you find a tone you like.
http://revolutiondeux.blogspot.com/2012/02/fred-briggs-64-vintage-vox-tones-galore.html
(http://1.bp.blogspot.com/-fP8XcZGurTY/TzgXw2rQVcI/AAAAAAAAA64/5MsxeogYNKg/s1600/briggs_64_vintage.jpg)
Quote from: Killthepopular on May 21, 2019, 05:49:26 AM
Would this work as a standalone buffer?
You'll have DC at the input, which probably isn't what you want. Lose R19. Out of your list of transistors-to-hand, only one is a BJT. The good news is (as R.G. will tell you) that you can almost always use a 2N5088 where you see an NPN BJT.
Quote from: bluebunny on May 21, 2019, 08:17:21 AM
Lose R19. Out of your list of transistors-to-hand, only one is a BJT. The good news is (as R.G. will tell you) that you can almost always use a 2N5088 where you see an NPN BJT.
Like this?
(https://i.postimg.cc/sBW3G5wQ/DS1-out.png) (https://postimg.cc/sBW3G5wQ)
Does it matter if i don't use those exact caps? Are they literally just there as RC filters? I have 15n and 0.1uf. 1M+15n=11hz. 100k+0.1uf=16hz.
...Actually I do have a 47n after all, but I don't have a 1uf.
I've tried the LPB1, Echoplex, AMZ mosfet, SHO and now I'm trying the stratoblaster. I've encountered a weird issue with the stratoblaster circuit. I'm recording identical clips of each circuit so that I can compare them all later. I'm using my ROG condor for some of the clips, but annoyingly the stratoblaster doesn't want to work with my Condor. The stratoblaster works fine with my amp or with my Joyo california sound pedal. It works fine going straight into the soundcard. The condor on its own works fine. But as soon as I go Stratoblaster -> Condor the sound i get is that weird, incorrectly biased, voltage sag type sound. Very quiet, very gated, then you hit the strings and a raucous, farty distortion leaps out at you. Then it dies away and goes quiet. It sounds like the way my condor sounded when I hadn't set the trim pot correctly. I've tried different batteries on the stratoblaster and different power supplies for the Condor and get the same results. Somehow the stratoblaster seems to make my condor incorrectly biased. That's what it seems like... Anyone know what's happening here?
Incidentally my condor uses a 2n5457, as does the stratoblaster. The ep3 circuit used a 2n5457 too and worked fine.
I highly recommend something like this:
http://www.madbeanpedals.com/projects/_folders/1590A/schematics/Bloviator.gif (http://www.madbeanpedals.com/projects/_folders/1590A/schematics/Bloviator.gif)
Acts as a buffer as well as a "nice it up" filter. The BBE/Aphex rack units were a fad for a while, people made outrageous claims, and they were abused by radio stations and jingle houses, so they have a bit of a bad reputation no. But I think that comes from people imagining their use tracking or mixing in a modern recording studio, where indeed, unless they make that "magic" sound that's exactly what you were looking for, they're not very useful, and/or harmful, and/or a PITA for whomever does the mastering. BUT, with a guitar in front of a tube amp (some SS are ok too, some fight it), something like the Sonic Stump project can bring out a much fuller sounding steel string tone, especially if you're playing clean.
Also giving the AMZ mosfet booster a vote, I've gigged with that thing for years. A simple textbook circuit like that often does everything you need without any crappy sound baggage from over-engineering.
Quote from: garcho on June 06, 2019, 04:09:52 PM
I highly recommend something like this:
http://www.madbeanpedals.com/projects/_folders/1590A/schematics/Bloviator.gif (http://www.madbeanpedals.com/projects/_folders/1590A/schematics/Bloviator.gif)
Also giving the AMZ mosfet booster a vote.
The bloviator is a lot more complex than the other circuits I'm trying. I'm building 6 different circuits, all of which only use 1 transistor and 8-12 other components. I've already built the AMZ mosfet.
I'll give up on the stratoblaster. Sounded good to me but just doesnt seem to want to work with my cab sim.
Here they all are:
(https://i.postimg.cc/FdVDyj6z/alembic-stratoblaster.png) (https://postimg.cc/FdVDyj6z)
(https://i.postimg.cc/Hj36j95P/DS1-out.png) (https://postimg.cc/Hj36j95P)
(https://i.postimg.cc/d7MBgHPD/EP3.jpg) (https://postimg.cc/d7MBgHPD)
(https://i.postimg.cc/jCqXVn96/LPB1.gif) (https://postimg.cc/jCqXVn96)
(https://i.postimg.cc/c6Dcd4yp/mosfet.gif) (https://postimg.cc/c6Dcd4yp)
(https://i.postimg.cc/v4n77rgy/sho.png) (https://postimg.cc/v4n77rgy)
I've done 5, just got the DS1 buffer left to try.
Anyone got any more ultra simple boost/buffer circuits of this ilk to recommend before I call it a day?
To reiterate, I'm just looking for a fairly transparent circuit that can manage unity gain but doesn't have to go much beyond that. So far I've found that, to my ears, 5/5 circuits that I've tried have made my guitar sound "better" somehow. Better impedance matching maybe? I don't know which I will build ultimately but If i had any 1 of them I would be inclined to use it as an always on pedal. That's how much of an improvement these circuits all seem to make to my guitar/amp sound.
I see all transistor based circuits. What about a simple op-amp booster? Something more simple than a MXR Micro Amp or MXR/CAE MC-401 Boost.
You can adjust the input impedence acting on a pair of resistors, and adjust the volume/gain acting on the gain resistor in the feedback. And of course a pot to use as master volume pot. I found a sort of it really transparent and with none distortion.
QuoteI'll give up on the stratoblaster. Sounded good to me but just doesnt seem to want to work with my cab sim.
not until we say.
we can't see the circuit of
your condor, but the one I looked at had no DC blocking cap at the input. and I see from your stratoblaster circuit [which also has no input blocking cap ....] that the output cap is a tantalum. if, perchance, you happened to fit that particular cap backwards, it might leak enough to re/mis bias the following input,
if it didn't have an input blocking cap.
measure the voltage at the output of the stratoblaster. is it 0V00?
actually, a second glance at the straoblaster shows it doesn't have ANY gate bias. you need a resistor from gate to ground, 1M, 1M5, 2M2, 3M3 ..... doesn't matter exactly. circuit won't work reliably without that resistor.
Stratoblaster was designed to get the gate "bias" from guit. vol. pot. Actually the internal resistance of any passive pickup would bias the fet. It looks just like a textbook fet amp adapted (simplified) for guitar. I had a similar ckt in one of my basses in late 80's. Well, it didn't last long in there...
Quote from: duck_arse on June 07, 2019, 11:26:26 AM
the output cap is a tantalum. if, perchance, you happened to fit that particular cap backwards, it might leak enough to re/mis bias the following input, if it didn't have an input blocking cap.
In the words of the great Hans Landa, "that's a bingo". I had already dismantled the stratoblaster circuit and moved onto the next circuit when you posted this message but i thought I ought to go back and re-build it seeing as you took the time to have a look at it.
When i built the stratoblaster circuit the first time, I got to the 1.5uf cap and looked and the symbol and thought "right, well I know from working with diodes that a straight line means the negative leg" and completed the circuit accordingly. When I re-built it just now I actually bothered to look up the circuit symbol for capacitors and found out that the straight line actually means + not -. It now works with my condor.
I'll add the stratoblaster to my other recordings and do some double blind listening tests (to see which circuit most appeals to my ears without a biased opinion) and report my findings.
Try a search for "booster buffer" in this forums advanced search
select match any words
You will find threads
Also look for the LPB, ecoplex etc. threads that have been posted over the years
A lot to read but it should be worth it.
Something I need to make time to build and test. The parts to the left of the input are a simple guitar sim with one single coil pickup
https://www.diystompboxes.com/smfforum/index.php?topic=99139.msg868712#msg868712 (https://www.diystompboxes.com/smfforum/index.php?topic=99139.msg868712#msg868712)
the tantalum markings have caught many a builder, many a time. do you have any non-working builds with them in?
a "straight line" on a tant should be accompanied by a row of "+" symbols (unless yer using surface mount parts).
Quote from: duck_arse on June 09, 2019, 10:22:29 AM
the tantalum markings have caught many a builder, many a time. do you have any non-working builds with them in?
Sorry, I should have been clearer. I was referring to the straight line on the schematic. Not the cap itself. The cap itself had a longer leg and two plusses on one side so it was obvious which way the cap was polarised, I just didn't correctly understand what the straight line/curved line symbol on the schematic meant. I thought a straight line on a schematic indicated the negative end, as with a diode.
I've only built one pedal so far, (the condor) and that didn't have any tantalum caps. I built that one from a layout, not a schematic so i could see which way caps should be oriented from the layout, I wasn't confused by schematic symbols.
ahhh, so, was the 10uF C1 a tant as well? and backwards, was it? the clue is in the ground symbol on one end of C1. the other end must be more positive than ground, and that implies the orientation of C2 as well.
QuoteI see all transistor based circuits. What about a simple op-amp booster?
+1
Have you tried a simple non-inverting op amp buffer as an always-on device? Could get away with no pots if you wanted. That was part of the obnoxious Klon hype that has thankfully passed, for the most part. Or you could try an inverting op amp with gain in the feedback loop, you can have less-than-unity gain, if you want (obviously as much positive gain as the op amp/ps permits), still ultra simple.
> which way the cap was polarised, I just didn't correctly understand what the straight line/curved line symbol on the schematic meant. I thought a straight line on a schematic indicated the negative end, as with a diode.
The original electrolytic capacitor was a round jar with a flat plate inside. The flat plate was "+". The symbol became a curved line for the "-" electrode. I can't even find a picture of that construction now, but that's the back-story.
There are a dozen other "standard" symbols. Google "electrolytic capacitor symbol" when in doubt.
I did a bunch of double blind listening tests using my humbucker equipped strat and my filtertron equipped gretsch. Mostly I found that these circuits behaved very differently from situation to situation depending on the impedance of the signal they were receiving. There wasn't generally a "sound" imprinted by the circuits but rather they affected the signal making it brighter or duller, sometimes improving it, sometimes making it sound a bit worse. Most of them would have benefitted from more headroom. All circuits were the schematics you see above and powered with a 9v batt. I did build the ds1 buffer circuit and thought it sounded good and had plenty of headroom but I didn't bother to include it in my recording/listening tests.
LPB1: Generally sounds good to me but needs more headroom. Sounds great if you want a dirty boost.
AMZ: one of the more inconsistent ones. Sometimes harsh. Sometimes dull and bassy. Often sounds a bit boring. Needs more headroom.
Stratoblaster: Another inconsistent one. Sometimes bright, sometimes dull. Good as a boost.
SHO: Seemed like it sounded good with humbuckers but was very unpredictable with filtertrons. Cool dirty boost tone.
EP3: Mostly well balanced but needs more headroom and doesn't have enough gain to be used as a boost.
I have no plans to build any of these. I went in expecting to find a magic circuit that would just make my sound invariably better but instead I found that the tonal qualities imparted by the circuits vary wildly depending on the impedances involved. I haven't found a magic tone pill but I have gotten a better sense of what impedance is all about.
If you're sticking a buffer somewhere the impedance won't change (say in an effects loop or as the last pedal on your board) then you can experiment and find a buffer that complements that specific situation. If you're looking for something that magically just makes everything sound better regardless of how it is used then a buffer won't do that.
Maybe this is obvious to you guys already but I suppose I'm the sort of person who has to try things out before he can trust in anything.
I didn't build the LPB-1 stand alone, I used that circuit in other situation, inside other pedals. Never built AMZ and Stratoblaster. I'm gonna build the SHO. I built a kind of modified version of the EP3 Echople Preamp.
You can solve almost all that issue (headroom, gain, dull, harsh...) with some mods in the circuit . Replacing transistors, caps, resistors and adding a charge pump. :)
Or with a dual opamp for a gain stage and a tone control and maybe a voltage doubler or inverter. :icon_rolleyes:
If you want a really clean, totally transparent boost for humbuckers with headroom out of a single transistor running on 9 volts -- you may be asking a bit too much. All of the circuits you tested kinda sorta do that, but they can't outstrip their own inherent limitations. Of course, those limitations are what give these circuits their special characters and tonal signatures, which is why people like them. IOW, a little bit of coloration or dirt is kind of the point. But for that super-uncolored thing, a high input impedance opamp design running on higher voltage is probably your best bet, like a Barber Launch Pad or a variation on one of the MXR designs.
Edit: I see Roseblood11 got his much more concise reply in a few seconds before me, and we are really saying the same thing.
For an off-the-beaten-path opamp option, you can also look at John Hollis's Titan Boost (http://www.hollis.co.uk/john/circuits.html), which works with a dual opamp and a small transformer to produce big boosts on 9v, and can easily be modified into an octave pedal. I've never used nor heard one, so I can't speak to its sound, but those who have seem to like it, e.g. forum member jmusser (https://www.diystompboxes.com/smfforum/index.php?topic=31771.0).
Merlin's Glass Blower (http://valvewizard.co.uk/glassblower.html) is another clean boost that uses some tricks for extra headroom. I've not tried it, but I've never been disappointed by one of his circuits.
Quote from: Ben N on June 10, 2019, 05:40:04 AM
For an off-the-beaten-path opamp option, you can also look at John Hollis's Titan Boost (http://www.hollis.co.uk/john/circuits.html), which works with a dual opamp and a small transformer to produce big boosts on 9v, and can easily be modified into an octave pedal. I've never used nor heard one, so I can't speak to its sound, but those who have seem to like it, e.g. forum member jmusser (https://www.diystompboxes.com/smfforum/index.php?topic=31771.0).
I'd like to find a veroboard layout of the Titan Boost. :D
Quote from: Elijah-Baley on June 11, 2019, 03:01:44 AM
I'd like to find a veroboard layout of the Titan Boost. :D
It's go such a low parts count that I doubt very much you'd need one, or, more correctly, that you'd have trouble coming up with your own.
Yes, indeed, in this last months I'm trying to work hard in some veroboard layouts by my own.
But, you know, If there's some verified layout around is better! ;)
I'm guessing this is on perf rather than vero, but just to give you an idea (and this is with a switchable octave): (http://www.super-freq.com/wp-content/uploads/2007/07/img_4610_25.jpg)
Thanks! I have the schematic, too. ;)
I think I'm finally gonna build my boost pedal. I've gone with a modified stratoblaster.
(https://i.postimg.cc/21jJv5M0/alembic-stratoblaster.png) (https://postimg.cc/21jJv5M0)
(https://i.postimg.cc/21HtxDfr/mini-stratoblaster.png) (https://postimg.cc/21HtxDfr)
I've increased R3 to 56K so I can get a clean sound with humbuckers and use the full sweep of the 50K pot (Changed from B to C taper). I had to change R2 to 220K which sets my drain at 5.2v at maximum gain. My next biggest resistor is a 470K so I think 5.2v is as close as I can get to 4.5v.
Sounds fine on the breadboard. Does the schem/layout look ok?
Looks OK to me.
Quote from: Ben N on June 10, 2019, 05:40:04 AM
For an off-the-beaten-path opamp option, you can also look at John Hollis's Titan Boost (http://www.hollis.co.uk/john/circuits.html), which works with a dual opamp and a small transformer to produce big boosts on 9v, and can easily be modified into an octave pedal.
Looks like it calls for a 1k CT:20k transformer, which Mouser doesn't seem to carry, or my search-fu wasn't strong enough. Any sources for one?
Yeah, that's a problem. ??? Mouser does carry the 42TM006--alas, the minimum order is 1000. :icon_eek: You can find them reasonably priced in lots of 10 on ebay, or unreasonably priced as singles. Maybe 42TM017 (25k:600R) would work?
Circuit built. Works fine. Boxing it up in a 1590A next.
(https://i.postimg.cc/189DWWH0/IMG-20200922-094143.jpg) (https://postimg.cc/189DWWH0)