/diy/ - Do It Yourself

>>314923
nothing worthwhile. non tube amps only need a bigger ot to push the speakers. better to buy them from Hammond as non musical pts will not be built with the same care.
if you have room, start looking for non guitar tube amps. best supply is old organs. for example, Hammond and Wurlitzer made stereo organs with a power amp for each speaker that had very similar tube setups as Fender guitar amps. I was given a power amp that was 1 tube away from a 5e7 tube setup.
people hate old organs. they take up all much room and usually don't work for shit. go grab em with a pickup as a junk haul and scavenge.

>The only problem is finding high voltage power transformers.
http://www.digikey.ca/product-search/en/transformers/power/786735?stock=1
.com if america.

How high of a voltage do you need? You can get ~340 peak DC if you have 120VAC on the output side of a 1:1 transformer. I know because I'm in the middle of building a tube amp.

>>314925
yeah, guess so. I really just want to scavenge them. I think newer tube (i mean tv's from the 90's) have transformers of +10k volts so they wont work.

>>314928
no I know I could just buy them but I want to salvage them if I can to keep cost down

>>314923
You're not looking hard enough online for transformers.

>>314935
I know I can just buy them, I wanted to try and salvage them though if I can. I want to start building amps in small quantities to sell on the side, and power transformers cost like 50 dollars or more.

my opinion is go find a person who winds transformers near you. You can get exactly what you want custom made.
And if you ask around you can find if someone has good experience at winding output transformers too.
BTW this is what I finished a couple of days ago... I am a little proud of myself I might say...

>>314934
also you are talking abut another type of transformers in these

and you won't find much quality in transformers made 50 years ago...

>>314950
do you know anything about 6dg6gt tubes by any chance? They're very similar to 6v6 tubes aperently, and you can get NOS RCA tubes for a dollar each on ebay. I planned on building the amp around those tubes. Know anything about them?

>>314972
well, no I haven't made anything with them specifically but from what I can see on the net they are close to 6W6gt tubes, and from what I read you can probably use schematics intended for the 6v6 perhaps with minor changes..

also, heres a circuit I found that I want to build. How bad did I fuck this up? I believe the transistor is in backwards on the perfboard, but what other mistakes did I make?

no actually the board seems OK if you are staring down at it from the component side (which I assume you are)
I don't know how to wire true bypass switches so not sure about this part.

>>314972
there's some problems with getting super-cheap oddball tubes online, and that's that they may suck balls for (chances are) audio, and you probably can't pair them at all, unless you have a tube checker...which I bet you don't.
I haven't built a tube amp, but I have been ready to build on several occasions. The lame part of it is that tubes are finicky and harder and harder to find NOS. Any tubes that are good sounding for guitar are already bought up by places like tubedepot.
it's not necessarily a bad thing, mind you. oddball tubes may just sound shitty. That's why they aren't used. Transformers are still being built by Hammond that perform better than NOS.
check this link out. remove the spaces.
http : // www .freewebs .com / cameramanlink / electronicsprojects . htm

I stumbled on this guys site. 12v, 24v guitar amps. Pretttty fucking cool if you ask me. Also worth while to look up sopht amps. Also the valvecaster amp.

What does everyone think about this idea? Using voltage multiplier circuits instead of huge transformers. You will still need something with taps for your heaters etc... Their are some people that have tried this music electronics forum and I'm sure other places but the results aren't exactly what they had expected. If someone could just get the formula right then it could reduce the cost and weight of tube amps-right?

>>315114
I think ART did that with their tube mic preamps. I have one, and there isn't any transformers hanging out anywhere. I don't know think they did the tube scavenging thing on it, though I dunno. I'm no electronics guy, just a hobbyist who's informed enough to kill himself with 400v.

>>315114
ok now I like this idea, I just have no idea how to get this to work. I need 3 b voltages for the amp I want to build, 200 volts, 180 volts and 170 volts. Now since I'm dealing with vacuum tubes they can be +/- nearly 20% but they still need to be closeish. How could I build a rectifier that would get close to that? I believe the power tubes draw 1.2 amps each and I forget what the 12ax7 plate draws but I think its about that

>>315099
the reason they havent been bought up is cause almost no amps use them. I just cant believe the only tubes that sound good in guitar amps are 6v6, el34, el84 and 6l6 (along with kt88's for bass amps). They designed literally thousands of tubes, there have got to be some good sounding ones. And even if they only sound 3/4ths as good, they are 1/20th of the price so they bring the costs way down

>>314923
the transformers is the difficult/expensive part about building tube amps. the transformers tend to be unique in their voltages, except for amps like 'standard' guitar amp circuits where you can buy (relatively) cheap replacements

most tubes only cost $5-$10 each, unless you want 300b's

a pair of matched output transformers can easily cost $150.... or you can make them yourself.

>>315144
yeah no kidding. I mean, you can fudge a lot of things while building them but to make them for a market that wants amps in a 200-500 dollar range its near impossible. Unless you go single ended

>>315124
I'm new to tube amp design but 1.2A seems crazy high for anything except for heater current. Everything I've read shows tubes being driven with high voltage @ low amperage which is why I think voltage multipliers might work because they raise the voltage at the expense of current but I'm not quite sure how this works exactly. Also there are a lot of "cheapo repros" on ebay, they can't be all bad.

>>315159
they were designed to use really high amperage for some reason. They made tubes for literally every possible use

But that aside, do you know how to design on of those power supplies or have any documentation on how to do it?

>>315160
go here. http: // www . behindthetone . com / johnfisher /

this guy has made every part of guitars and amps, and described it's process. He's also a religious nutjob, I think.

>>315129
there's a reason amps usually don't use them; they don't sound very good. A tube is just an old prototype of a solid state transistor, and a not very good one at that. As tube design evolved, tubes got closer and closer to being "perfect" transmitters of signal. The problem with that is that these more perfect tones end up sounding like transistors as well; blah. Guitar tubes are old designs that sort of suck at their jobs. These were bought up by low-end music electronics manufacturers to jam into their low quality/high profit items. The later designed tubes that you'd find in hifi circuits tend to be better at their job, which makes them 1) more expensive to buy back then, 2) sort of lifeless in a guitar amp.

Look at the mojo a Kalamazoo, Silvertone, or Valco amp has now. They aren't high gain, but they're suuuuure toneful. Well, they're made with some of the lowest-quality pieces you could find back then.

but then, why not experiment? My point has been to point out that others have, and have found failure. Sopht and that first link I posted use "space-charge" micro tubes to get amplification at 12v because they used these tubes in fuckin car radios! They use a 12ax7 for a power tube.

you may also want to look into tube power stages or tube tone coloring, like the Vox VT amps do. They put a 12ax7 in the output stage of the amp to give a little sag and breakup.

Lastly, I do wanna say; if you're thinking of trying to sell em, you'd really be better off making the cabs. You can buy a moddable 5w-15w full-tube amp for low low prices now, something that you may not be able to compete with profit-wise. The cabs, on the other hand, can get from 250% and up return if you make nice ones.

>>314940
$50 is a small investment.
A homemade tube amp classifies as "boutique" and people just gobble that shit up. If you make a tube amp that sounds just somewhat good, you'd easily be able to sell it for $150.

Build in some distortion effects or a 4-band graphic EQ and you can notch the price up even more.

So yeah, stop bothering scavenging transformers and just buy them.

>>315078
Nah, your transistor's fine.
I'd probably wire the stompbox a little differently, but the schematic itself seems fine.

What's it do?

>>315078
Oh by the way, here's a pretty nifty scheme on how to wire stompboxes.
Without DC jack, it runs off battery.
With DC jack, battery's disconnected.
Turns on when the input jack's connected ( standard 3-prong stereo ) and switch engaged.

Gotten from Beavis Audio.
Happy building!

>>315200
Its more or less a clone of the ZVex super hard on, a boost/distortion. They claim its a clean boost but I have the actual pedal and its got a gain factor of like 3600 (with 2 together). I like it though.

Heres the revised circuit

>>315206
Oh, sweet.
I think I'll breadboard one, see if I like the sound.
I'm currently building a DOD 250 clone, hopefully it'll sound at least somewhat like the real deal.

Looks much neater.
By the way, what circuit designer are you using?

>>315207
diy layout creator. Great program other than the fact that it is slow as fuck.

I wonder how the market is for these handmade pedals. I'm trying to get a startup going with them. theres certainly enough interesting circuits floating around online to start a line of handbuilt pedals without even designing any yourself

>>315213
Outside of Etsy, I think people would be more willing to buy the originals - at least in the case of other boutique pedals, like the ZVex SHO.
But don't let me ruin your fun, give it a shot. I'd recommend just building singles to test the waters, or make to order so you don't end up with 20 Fuzz clones you won't ever get rid of.

>>315245
the music scene around here is pretty booming and most people cant afford the 350+ price point of ZVex pedals. I can make clones for like 30 dollars. Theres a local music shop that would probably stock them and I bet if I sell them at the price point of BOSS pedals they'll fly off the shelves. Till I get sued.

One last thing: does anyone know some simple but relitively unused effects? I was thinking about building this lineup of effects:

ZVex super hard on boost
ZVex super duper
EA tremolo or like
Some sort of compressor
That crazy marshall simulator
and that armstrong green ringer modulator

>>315078
>>315078
Remember to ground the in and output.
For the transistor look up pin configuration from the datasheet.
And I would probably add a decoupling cap to avoid noise from the supply.
And instead of R4 which I assume is just to get the voltage down you could use a voltage regulator to make sure you get exactly the voltage you want.

Does anybody have experience with building small amps and/or pedals to sell?
I mean, is it worth it?
Quick glance tells me pedals and preamps are approx 20€ or so in parts. Question is if I would be able to sell them with a profit...

>>315283
you can make zvex clones?
If you show me a demo of one you make, I think I'd be interested in getting a couple.

>>315482

R4 is the drain resistor. It converts the FET current into output voltage.

>>315485

We have at least one dude who sells guitar pedals. The innards are pretty much same shit as in all these diy pedals. I think the main selling point of his creations is the looks. No idea how much money he makes.

here's a tube circuit that uses a charge-pump circuit to get the higher voltages from 12v.

voltage multipliers are unfeasible for an amplifier.
Remember, conservation of energy. If you have a doubler you will need to feed it V and current I to get out 2*V at I/2. (Simple principle, voltage gets doubled, current gets halved power stays the same) Now if you want to get 300v from 12v you will need to supply many amps at the input, which will be unpractical as you will need a high amperage 12V transformer. Not to mention that you will have greater losses due to heating owing to the big currents... And also multipliers have a ripple problem... you would have hum.
Thats why a multiplier could be used to power a preamplifier which has minimal current consumption but not a big amplifier.

Now about non musical tubes...
This is a myth that there are four or five types of tubes that "sound" good or that are "musical" and it is perpetuated by the big amplifier companies that use the same schematics over and over using the same tubes.
(many of these schematics are not even well designed)
Most of the tubes used in audio amps were designed for high frewuency use as well... the 6L6 wasn't built for guitar amplifiers.
Any tube that has a linear region and is not noisy (for example a heptode would be noisy due to the many grids) can be used for audio...
ffs I am using voltage regulator tubes for mig fighter jet radars in the amplifier I've posted above and they sound clean and crisp.

>>315499
Im going to be building a SHO clone in a few days. Send me an email (poisonwater@lavabit.com) and we can work out a deal. If theres any other pedals you want we can work something out

>>315517
thats brilliant, I might have to try that

>>315485
try ebay. They'll sell for a about 3 times the cost of making it. Amps are tougher.

>>315500
more or less. I mean theres people like devi ever who make like 20 different fuzz circuits but honestly they all sound the same to me.

>>314923

HV transformers are hard to find small and cheap these days. I know no one likes the idea of two transformers, but two SMALL easy to get transformers is cheap and not much larger.

Get line-to-12V for your low voltage DC stuff, and another, smaller, 6V-to-line trans. Put the 6V secondary on the 12 VAC feeding the LV DC stuff. Now you'll get 2 x line on the output of the 2nd transformer.

If the 2nd one is "small" (< 1 amp rated 6vac out) the ohmic resistance will be high enough to not get hot, and since the "secondary" (now the primary) will only draw 10's of mAs for the HV side (use a bridge) overall power through the 2nd transf will be well below rated.

>>315159

the only thing wrong with voltage multipliers is that they tend to multiply voltage variance at the mains too.

contrary to popular belief tube circuits benefit from power supply regulation. the reason they were not regulated before the semiconductor era is the difficulty and expense! Tubes make shitty series regulators cuz of limited currrent and high internal resistance. Also, standards were low back then! Seriously 10% distortion was considered acceptable.

>>315283
That's a pretty shitty thing to do, though.
I earn my money from making websites, and there are people in India severely undercutting me by offering to work at $4 an hour, compared to my $30.

You're doing pretty much the same thing. Don't steal another man's respectable work and sell it. I'm fairly certain that hobbyist manufacturers release their schematics so people can make their own, not so people can steal competition from them.

>>315712
so what would the output voltage be on 2 12 volt trannies?

>>315760
I'm not planning on selling exact clones, but I was going to use their SHO circuit as a base of a lot of my designs because its a really nice circuit

>>315768
In that case, I take my somewhat harsh words back.
Good luck bro.

>>315517
This guy is taking his +30V and +60V from the wrong side of the multiplier.

>>314972
Well I was looking around and I chanced upon this scematic for 6W6 tubes if you are still interestsed...
http://tubes-valves.blogspot.gr/2009/09/tube-12at7-6w6-push-pull-15watt-p0wer.html

>>315889
neat circuit actually. I'll look into it