Hi guys,
just finished this tube based overdrive, three stages, first stage (right footswitch, first valve from right) is EF 86 based on Renegadrian's EF 86 ( can be found here http://www.aronnelson.com/gallery/main.php/v/Renegadrian/EF86+Preamp.gif.html) , next a 'splitcaster' (based on the 'Matsumin Valve Caster' and 'Renegadrian's Twincaster') being a two stage 12 AU 7 overdrive.
The only piece of silicon is the 7660 charge pump on a Madbean Roadrage board to supply 24 volts (so far nothing is smoking....).
The pedal itself runs on 12 volt. Enclosure I made myself out of a piece of aluminum profile I found at the local recycling centre. I'm a sucker for polished look, so a few hours and a bit of elbowgrease later, sheets of sandpaper, buffing etc, this is what it looks like. Dimensions are 250mm wide, 100 deep, 30 high.
After initial soundtesting I put an extra master volume after the extra 12AU7 stage as the volume jump was to great from light drive to the extra drive, so that has sorted it well. The extra pot is external accessible beside powerjack.
I haven't done any labelling, not sure what I will do there.
Hope you find this interesting.
Cheers
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... and here's the guts: looks a bit more messy than planned as I had to experiment and change a bit around, extra master volume etc, but works sweet now.
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... and a closer one with the Roadrage charge pump board. Cheers Madbean!
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... and a close up of the "engine room". ;D
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Sweet mercy!! Throw an el84 power section in and sell it to me!!!!!
Amazing work!
Quote from: sprayfe on April 02, 2011, 03:23:57 AM
Sweet mercy!! Throw an el84 power section in and sell it to me!!!!!
Amazing work!
Heehee... You need a bit more power for that...
Gobstopper - is this all a starved plate design?
Jacob
Cheers for comments! Yep, it's starved plate design as highest voltage is 24 volt inside, external walwart supplies 12V 1.5A.
Andy
Love to hear how it sounds, I've been totally GASing for a Effectrode Tube Overdrive
I really like the look, its come together really well... nice job :)
+1 How's it sound?!?
DUDE :o :o :o :o :o
Quite awesome!
Thanks for comments, guys!
I'm not a snobby tube purist, I've built some nice silicon based stuff and I'm looking forward tp the next projects, particularly UniVibe, Screwdriver, LesLius.
Anyway, obviously this one is more the non silicon type...
Unfortunately I don't have any decent (or even half decent) way of recording at present, hope to get that sorted at some point.
So I'll try to describe it a bit:
first stage EF86 booster has a nice gritty breakup and I like the balance between warmth and edge. You could say it adds a bit of vox tone to it. At present the tube that I have is only a Russian sort of workalike to EF86, I do hope to find a good specimen of a EF86 with exact specs, will see how that sounds. With this tube it needs to be cranked quite a bit, unity gain is at 3 o'clock, so I have it dimed at this stage to get boost and a bit of grit out of it. Nice as a standalone boost and to kick following stages more.
The following 2x 12AU7 stage: left footswitch is on/bypass, middle footswitch engages/disengages second gainstage tube. Sound with one tube is a bit like a cranked tweed (5E3 or so), light overdrive, nice meaty stuff. Think Keith Richard/early Stones sounds. The second tube engages adds quite a decent amount of gain to that. Not a lot of compression with one tubestage, a bit more with both engaged.
I've tried also a 12 AT 7 but that didn't sound great, likewise the circuit doesn't work for 12 AX 7.
Like I guess some tube circuits the dials/settings have some sweet spots and others that don't really work so well with guitar/amp combination. I still have to experiment a fair bit with that as I only have just finished it and I will try a few different tubes as they are obviously the main driver of sound characteristics. ::)
Cheers
Andy
That looks great man. I have been looking at Renegadrians layouts for awhile to do a "valvecaster" type of tube pedal. This is really inspiring!!!
I'm guessing you already have experience working with tubes gobstopper?
Cheers again!
This low voltage stuff is really not that complicated at all, as long as you put the right connection to the right tube pin etc.
I have been building two 'Matsumin valve caster" before like this: http://www.beavisaudio.com/projects/ValveCaster/ and that's a very straightforward build that sounds nice already, this one runs on 9V draws around 150mA current (battery obviously futile...). A great starting point.
Use a good regulated and filtered powersupply and measure that it's really 9 V that it's pumping out, otherwise it might blow the tube heater that runs on 6.3 V.
Getting a good tube is like in an amp important to get happy with it.
I've also been building some tubeamps/high voltage stuff (photo is a Bassman/JTM 45 cross and tubedriven reverb/vibe on top) before but it's really not necessary to have done that to build this stompbox stuff; no chance of electrocuting yourself in the low voltage stompbox designs ;).
If you have high voltage on the floor spilling a beer over it wouldn't be such a good idea... every drop is a waste...
Andy
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Cool thanks for the info. Have you done anything with the sub-mini tubes? I do not know much about them.
But I shall start on the Valvecaster soon hopefully. Any mod recommendations to do right off the bat?
:o :o DANG :o :o
I was gonna say it before, but I'll say it now: I love your stuff, gobstopper
Someday I wanna build an amp...someday far, far from today :P
I've built a submini amp like the "frequency central Murder One" (google will help you there again...) that uses a 6111 as first tube. Fun build; but not an overdrive stompbox.
Mods for the Valvecaster: adjust C1 input cap to taste for more or less bass response, for example 22n rather than 47n for tighter/lesser bass or make that even switchable. Depends on your guitar/amp combination, I ended up with the stock values for my taste.
Cheers for comments again.
Andy
Madbean also mentioned a submini amp at some point as a project for this site here.... would be great!
They're fun things to build and have... the output of the 'Murder One' will be about 0.3 watt I guess; crank it babe...... no trouble with the noise control officer.
Andy
Wow. That's all I can think to say! You should be proud as hell!
Good stuff! Thanks for sharing.
Josh
Thanks guys, there's tons of great and proud stuff on this forum here.... good to be here!
Cheers
Andy ;D
There's a huge thread about the Valvecaster here
http://www.diystompboxes.com/smfforum/index.php?topic=63479.0
and credits to this guy: http://www.matsumin.net/
Cheers.
Wow!!! Dude you are in another level...this looks incredible!!
-Kaleb
Those look soooo nice!! I'm very impressed sir!
Building/repairing tube amps is why I got into this whole pedal madness and I sometimes wonder if I just heavily distracted myself from what I really wanted to do! I'm still wary working with high voltages but seeing builds like that makes me want to just jump in and start.
Did you use kits to build these? I've looked at ceriatone and some of them seem possible for a beginner. Also AX84 seems like its suited for beginners. What would you recommend?
Cheers for comments!
I don't wanna turn this into an amp building forum, so keep this brief:
there's a bunch of good ones out there, some of them getting a bit nutty as people discuss the colourshades (and maybe the taste and smell of...) of mustard caps of different periods in Marshall amps and the like.
AX 84 is a good starting point I guess, they alkso have lots of links to other sites.
And definitly read the safety guides for tubeamps on those sites several times and understand how to put it in practise, then you'll be fine. :o
Ceriatone kits are probably not a bad thing, I've built one of theirs (Dumble Clone HRM 50 Overdrive Special) which worked great and was a well presented kit.
The amp and reverb unit on previously posted photo are built from scratch (as in: scratching the parts together from different sources, bending and drilling the chassis, whacking together cab).
The attached photo in this post is of inside of amp.
Cheers
Andy ;D
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Cool stuff man. I've been thinking of an amp build once I have the cash flow.
What do you think of the Bassman/JTM45 you built in terms of sound?
Does it need to be loud to sound good?
How well does it work as a pedal platform?
I've looked into doing a JTM45 combo to use for practice, which is why I ask. We play at medium volumes.
J
Cheers,
how do you describe sound and if it would be something you'd like?!?
Anyway, to me it sounds killa!
This one is a bit cleaner than the original JTM 45, a mix between Fender Bassman Tweed and Blackface sound, slight breakup with vol increase, wonderful on single coils.
With the tube reverb in front it never fails to wet my girlfriend...
The output transformer is a Sears Silvertone, has just a bit more compression and I dig that.
I used to have a Fender Hotrod Deville and it was the first thing I sold after this did it's first sounds... the Hotrod totally sucked in comparison.
Loud enough in my opinion, keeps up nicely with what I'm doing in band stuff and we sometimes whack it out in spades.
Like many/most single channel old tubedesigns it works great with pedals in front.
Cheers
Andy ;D
Quote from: gobstopper on April 07, 2011, 07:09:46 PM
Like many/most single channel old tubedesigns it works great with pedals in front.
I bet it takes analog delays like a charm!
Sorry for bumping this Very old thread obviously but does anyone have information regarding the EF86 boost? I've an EF86 channel in my amp and have acquired too many EF86/6267s. I'd be interested into looking into EF86 boosts if anyone has any information.