What to build for first tube project?

[347sixtyseven]

Hi guys,

After some recommendations for a first try at a tube project.

I have just acquired 1 12au7 and 1 12at7 and i am wondering what would be a good first project?

Open to all suggestions, although i am probably leaning towards od/dist or baby amp circuits.

Cheers

Gary

[Scruffie]

Well I think the classic that either of those tubes would be suitable for is the Valvecaster which has a sweet tone or if you want something a bit more interesting the Vibracaster for a tube vibrato/fuzz, both pretty simple and can be built on a small piece of vero/perf and no high voltages involved.

Just my $0.02

[bassmannate]

I agree with the Valvecaster. I just built it and it's a super simple build. Really helped me understand how tubes work. Also, like Scruffie mentioned, there are no high voltages to worry about like there are in most amplifiers.

[Thomeeque]

Hi guys,

After some recommendations for a first try at a tube project.

I have just acquired 1 12au7 and 1 12at7 and i am wondering what would be a good first project?

Open to all suggestions, although i am probably leaning towards od/dist or baby amp circuits.

Cheers

Gary

My first tube project was two-channel 50W amplifier - I don't think you need to start with aboslutely simplest tube project possible, if you already have experiences with radioelectronics and you know how to work with high voltage. IMO you should build, what you need at the time - you will learn on-the-fly, as I did

My concrete tip for you would be "Tiny Terror" clone.

T.

[Ripthorn]

I would say valvecaster for the 12au7 and for the 12at7, maybe try renegadrian's tube star overdrive.

[JKowalski]

IBM 701 Defense Calculator, 1952.



In all seriousness, though, you should probably tell us whether you would be okay with high voltage work or not, that'll narrow it down alot!

[MikeH]

Defense calculator?  So it that basically a 1950's number cruncher?

When it comes to tube, high voltage is so much more rewarding... but also so much more dangerous.

[frequencycentral]

Valvecaster. Without a doubt, you have to do this first. Easy, rewarding, well documented. Debugging a speciality. But beware................it can easily lead to other things!.   

[Renegadrian]

As Ripthorn kindly suggested, you may try my TUBE STAR if you're after high gain - else the Valvy is a classic among us tube addicts!!!

[Paul Marossy]

You could build a Firefly. That was the first tube amp that I built. It had a nice tone, too. I had to sell it because I need money, being the unemployed bum that I am.

[347sixtyseven]

Thank you for the helpful replies guys,

I will have a close look at the valvecaster and tube star for now.

I would like to build an amp but at this stage i cannot justify the costs of the transformers required.

Thomeeque, do you have any info on the tiny terror clone?

Cheers

Gary

[Thomeeque]

Thomeeque, do you have any info on the tiny terror clone?

Definitely!

Here is the "original"* AdmiralB's schematic.

Here is the thread which was my main source of informations, I advice to go thru it (it may be sorted in reversed-chronological order, so don't get confused ).

Of course, there is a lot of mods possible to do (I've made few either ), but you won't make any mistake if you will stick strictly with original (and mod later ).

BEWARE: If you will google for OTT clone info, you will soon or later come across this layout, it is very often reffered - it contains at least two flaws (first stage is not grounded and master volume dual pot is wired in wrong way). And I've already seen some redrawn schemo, where some original component values were wrongly interpreted. My point is: if you would plan to use such sources, always double-check with original AdmiralB's schematic, it is verified.

Good luck (& feel free to ask), T.

*I have never come across other complete OTT schematic, which was not based on this one.

[newfish]

Having gigged alongside people with 'Tiny Terrors', if you *are* competent with High Voltage, I'd say build one.

It's a fantastic sounding amp - especially through a 4 x 12".

[Thomeeque]

Having gigged alongside people with 'Tiny Terrors', if you *are* competent with High Voltage, I'd say build one.

It's a fantastic sounding amp - especially through a 4 x 12".

YES!

And there's a lot of (highly enjoyable) demos on YouTube proving it..

T.

[petemoore]

  1rst rule of tubes includes all the others: "Only work on stuff you actually understand". At that point, to further your good experiences [that's what we're going for] a kit is a great suggestion, however, something used with a 3rd prong for "AC grounded chassis" can be good, you really need to know how to safely work on amps, buying a used one can be the 'best for least" [amp/investment] approach.
  That said...
  Transformers lurk in strange places !
  I'm sure there are some at the dump, but it's easier to get clean ones before they make it that far.
  Put the word out: Any old electronic junk [especially the 'heavy' kind with tubes /transformers] wanted. I was surprized how transformers 'magically appeared'...their capacitors fail them and a big question mark appears above the head of the person sitting on them, this is often easily replaced with: "They're valueable, but only when 'it' lets them work [say it was a working phonograph].
  Then ya get yer wimpy 2 volt, AC [transformers don't usually 'do' DC] wallwart, and test transformers with that. Often times the transformer and tubes are all connected, and will work, but the Electrolytics in the amplifier PS needs replaced, in my case, it time before the transformers appear, sometimes a bit longer before the person sitting on them realizes they haven't a clue where to start with them and would just as soon send them to the dump...then let you have them.
  Don't unabashedly work on high voltages, start by seeing how easy mistakes are to make by stumping yourself, and learning many times/many things...safe, at low voltage.

[347sixtyseven]

Thanks again for the info,

I have just found out i have to go away on a training course for 3 weeks starting monday. I will have plenty of time to decide what i want to build.

Will let you know what i go ahead with.

Oh yeah, be prepared for more questions

Gary