Demo of the amp I designed and built.

50 watt EL34 beast built on the bones of one of my traynor PA heads from the 60s. Hiwatt inspired with some vox and amrshall thrown in as well as a few of my own ideas. Recorded at a jam session 2 weeks ago. First half is the solo guitar, no EQ. 2nd half is the same recording mixed in with the rest of the band. Mic was a lowly sennheiser e609 into whatever rpeamp is in ym buddy's itnerface. Nothing special. Played my SG with old t-top humbuckers. Speakers were two 8ohm EV SRO alnicos ins eries in an open backed cab.

song sounds great. amp is killer. playing is great. I just love everything about this. also the bass sounds killer

tht's my oldest friend.. its a weird bass he built himself and an old ampeg b25 I think... just a beta57 on a 15" speaker

Amp sounds great. Love it.

I dig it. When do these go into production and what's the MSRP?

hand made to order I guess... 1 off features could be available... I could probably make you one for about a grand? make that 2 grand, good quality transformers can get pricey

I think a production amp would be a 1 channel isntead of my 2 channel prototype to keep costs down with 1 less preamp tube and way less of the big electrolytic filter caps needed as a result, honestly the channels are only a few parts difference in the signal path but the support circuitry for the dual channels is a pretty big expense particularly because it uses 2 triodes for mixing them isntead of a couple resistors, a much mroe hifi way to do it versus fender, marshall and vox amps...

options would be a bright switch to revoice the normal channel into a brilliant channel (not to be confused with a typical bright switch or bright cap, the changes a couple of parts to change the voicing and gain structure a little and with the gain at 10 bright mode will still be brighter or rather less bassy with a few more dB of extreme high into the next stage, unlike a fender type bright cap on the knob that passes more treble at low levels and goes out fo the circuit as the knob reaches 10), and an option between an independent midrange knob or a midrange cener frequency 3 way switch (more useful, trust me, but if you must have a midrange knob, why not? Ic an give you either or)... I could also give you a marshall style presence control instead of my presence circuit, which works really differently in a different part of the amp. Personally I think my presenc circuit is a lot more useful. I could also give you an alternate master volume control and an effects loop, but again, that's going to cost a lot more. lots more parts. It also won't sound as good

it would be built ona 50 watt marshall JMP master volume chassis with heyboer tranformers

if you really wanted I could build a full on 2 channel and even give you a 'bridge' input but that would run the cost up considerably due to the extra power fitlering and larger power transformer needed and make the build take longer. If you do a 1 channel I can use an affordable Classic Tone marshall replacement power transformer, but for a 4th preamp tube I will need something more robust and therefore more expensive.

I could also make a small version, like a little 15 watt one with EL84s or 6V6es if you really wanted.

Build turnaround would be about 30 days including the wait tiem on the big parts.

I think a 1 channel version would kick ass, since the breakup on this amp is so fucking crisp. I'd be willing to make that compromise :P

right now the control set is really basic, the 1 channel verison would be Gain, defeatable Master, TAreble, Bass, Presence.... optional bright switch, option between a fully adjustable midrange control or a clickable 3 way midrange center frequency control. I think the way I designed the amp the center frequency control would be a lot more useful. THe tone controls are passive but as you turn them up the way they act is like they boost everything on either side of a specific mid frequency where both knobs turned down is like a dead flat frequency gain cut. They do effect eachotehr. Bass can boost more lows with treble turned down some and vice versa. The stock notch is centered at 350hx so like if you put both controls to 10 you have close to flat gain with a strong mid scoop centered at 350hz, taking all the mud out of your signal, but by about 800hz you're getting abck to full gain so the amp still barks. If I put ths one capacitor on switch with 3 different values instead of the one I chose you will be able to click through thoe 3 different vlaues and move the midrange dip up higher. I designed a circuit theother day that will click you from 350hz to to 1khz (the metal scoop frequency) to 3khz (which will allow you to get brighter and drivier with less of the sizzly upper midrnge zing if you want). I could put a wider range than 3 caps, but I think those are the three caps that will jump out as different. Its a aprt that absically controls what frequencies the treble control'hears'. In my design (and some early hiwatts) the treble control is designed to 'hear' a lot of midrange whereas using smaller caps like vox or some fenders with these types of tone cotnrols causes the treble control to hear elss midrange and the midrange capacitor/resistorlimiting network on the 'bass' control to hear mroe of those frequencies. I can give you a combination of indpendent midrange and a midrange 'center' cotrol too with a push/pull midrange pot, but you cna onyl get 2 frequencies then. For my own use I like the crazy low midrange dip and the ncie full amount of upper midrange hitting the treble control isntead of the abss control, but for more modern styles I'm not sure... this design has the micrange that people boost into vintage amps that have a scoop there like fenders.

That is some super clever design. Makes the amp really versatile... you're tempting me and I just bought an amp last week :P

you probably can't afford it... I can't build it cheap unless you have a suitable donor amp to mod already, and that takes some tiem to gut a suitable amount of the original amp without damaging anything you'll need later. The more stuff thatc an eb sued form the donor the cheaper the build will be. I put very little money into ym prototype ebcause the amp iw anted to build could use msot of what was there in the tube PA. I needed a few caps, a few resistors, new fitler caps and some potentiometers. Maybe $100 investment, but you would ened a good hand wired amp around for me to hack into or at elast soemthing with off-baord tube sockets and suitable transformers so I can easily lift the old PCB and put in my own temrinal strip and pots for the controls. Like, there are a lot of 80s EL34 based amps i could make nto a jim-watt, but not many cheap 90s amps. At that point the cosntruction emthods had gone wya down the toilet for doing this sort of thing.

but from scratch the transformers will be about 300 bucks, the chassis to build it on is about 100 for 9 or less. Defintiely not going to order 10 when i'm not actually a company LOL. about 200 bucks in electrolytic caps... 100 bucks in loose resistors and signal caps, 100 in potentiometers and the bias trimmer, 200 for sockets, switches and switching jacks... then there's tubes, a 1 channel will be whatever a JJ retube set for a marshall costs, so maybe $150? Not sure. and Im running low on suitable wire so throw in 50 bucks in solid core hookup wire and shielded wire for the tone section... so about a grang in aprts without a headhsell or any controls panels. I also forgot the cost of a board.... but that's a few bucks if I just get some genereic eyelet stuff. if you want anything fAncier like turret or terminal boards it'll cost you because those have to be customed toa certain extent.

the tone controls aren't that clever, they're just a classic type of 2 band setup (really 3 band, but the mids are shared out between the 2 controls) carefully engineered to suit my aesthetic. You can sit with the Duncan toenstack calculator and punch in different values all morning while you have your coffee until you get something that behaves exactly as you want in every conceivable control position, then you just rustle the aprts out of your bin and see how it works in practice. As logn as you're sticking to a classic tone control design that's in the software's library you can chnge the values around and simulate to your heart's content instead of sitting and doing tedious amounts of algebra like they had to back in the 50s and 60s. Although you still ened to know some basics like what the impedance is coming out of the driver stage and like what the resistance laod is on the output of the tone stack... but you know, that's not rocket science and if you have something built up you can just get your meter and check if you didn't do any of those calculations while designing the amp. Its not as versatile as you're thinking,t he amp has a very specific voice and any added features are more like fien tuning. It sounds like it sounds. If I wanted a mesa I'd build a mesa. I have a like it or lump it approach to design. I designed this for ME.

It turned out GREAT. You're right, I won't be able to afford this for a while, but goddamn. Sounds awesome man, best of luck

I would bulk order parts and build a bunch of them to sell, no pre-order, for a somewhat more reasonable price to people who wanted them but I just don't have that kind of money sitting around. It wouldn't be very responsible parenting to dump all our money into parts for a hundred tube amps either.

I'm seriously thinking of starting a kickstarter to generate funding tos ee if I can do an affordable version of this design. I would still do handmade ones to order for 2 or 3 grand, but I'm imagining a PCB version with minimal handwiring and less costly (but still good) transofrmers custom specced. to have runs of faceplates, PCBs and transformers done up I would need startup capital I don't have.... a big roder of cabinets and chassis will cut costs too so kickstarter. Now does anyone know how to generate a ton of kickstarter interest?

hit Twitter, affiliate w/ charity (?)

Can we see pics of this bad boy?

brace yerself… the prototype is HIDEOUS, its a converted traynor PA head (I started modding one of mine and then just gutted it and rebuilt it my way) ... the wiring inside isn't even that tidy, the whole thing is a bit embrassing but tis a 1st draft... its actually a miracle it doesn't hum and squeal LOL a better thought out and built version should be admirably low o hum and stray abckground noise.

its actualy at my band's rehearsal space right now so next time I'm down there to work on tunes I'll take pics. I'm planning to make a video going through the limited feature set too, hopefully that will help me wring some money out of people so I don't have to finance my amp business dream by taking food out of my kid's mouth. But I don't have anyone to babysit this week so The Lux took the week off from jamming... probably next week we'll get back ina ction. Oh yeah, I started a new band with my odlest friend. That idea kidna prompted me to design an amp because he asked me not to use ac30s and I wasn't happy with my EL34 heads for this so... there ya go

We could mod this design to do bass really easily... I could literally double the size of a capacitor and remove another capacitor from the tone circuit that limits the really low lows and it'd have a pile more bass... if you want a cleaner sound (this amp breaks up between 3 and 4 by design, tis like a gained up early hiwatt) I could change a few values in the tone controlsand move them to another part of the preamp too, hen at your discretion you can use lower gain tubes in the phase inverter slot, a 12at7 will sound really good ther and give the power amp more headroom... for a bass amp I wuld probably beef up the pwoer supply, use a giant output tranformer and go from 2 el34s to 4 kt88s for 200 watts if you intend to use it on any decently sized stages.

I can also take part of thsi design and make you a rackmountable bass preamp with a low impedance output to drive any power amp you want.

either that or I'll start with a clean sheet of paper and design you something but you gotta tell me what you want. I like british amps, but if you like soemthign else I can listen to your ideas

Can we see pics of this bad boy?

brought it home to track down a cold solder joint and to tweak the gain staging one more time

https://imgur.com/a/w5LTOtX

not oretty, built on one of my traynor YVM PA heads, but pretty much gutted and rebuilt from scratch. I think I kept the traynor bias supply for the power tubes and that's it. The rest of the pwoer supply is completely redesigned and of course the preamp is from scratch. This amp ahd the right amount of tubes and very robust powere transformer and choke that can supply them without any trouble... and the ouput transformer is this ancient hammond BEST although a producton version will probably use a partridge output which is about the only upgrade you could make from what's in the prototype.