Pre-build Consult

So, after the past few weeks of looking around I've decided that I'm ready to jump in and take on a project to occupy me for the winter. This thread is to serve as my planning center to help me get all my ideas and materials straight before I start buying things. It's important to mention that I have NO experience with building electronics and NO tools. At its best, this will serve as some sort of a guide for other people who are thinking of taking the plunge for their first time. At its worst, hopefully you guys can have some laughs at my expense. Let's get started.

The Amp
I haven't picked any particular kit or model that I hope to use/emulate, but I do have an idea of what I want. My goal is to build a small, low-watt bedroom amp head that will get saturated and break up nicely at sane volume levels. I've seen some videos (http://www.youtube.com/watch?v=j3K_52YwU9o&feature=related) of the Firefly project (http://www.ax84.com/index.php/oldprojects.html?project_id=firefly) from AX84.com which seems to satisfy all of my goals, although they list it as being of 'intermediate' which might be a bit much for me (although I assume the available PCB (http://web.me.com/calhoun/Site/Firefly_PCB.html) could make it a little easier). Being that this is supposed to be a crunch box (my other amp provides all of the headroom I need), I really like the idea of having a gain control. A tone knob might be nice too, but not totally necessary since I'm really hoping for a compact, portable mini-head. I ran across this guy's (http://amplifiers.amplivibe.com/firefly/) page, showing off his ultra compact build which is kind of what I'm hoping to get somewhere close to (thinking a build into a lunchbox would be pretty slick, but too cramped?) Is this a bit too much of a project to take on for the first time? Anyone have other suggestions that would meet my goals?

Supplies
I should mention that I have NO supplies as of right now, so I'm all ears to hearing product recommendations (brands or general specific tools) that I should get. Right now my list is a bit short, it reads as follows:

Digital Multimeter (thinking this Equus 3320 (http://www.amazon.com/Equus-3320-Auto-Ranging-Digital-Multimeter/dp/B000EVYGZA/ref=pd_bxgy_auto_img_c)?)
Soldering Iron (just an iron (http://www.amazon.com/Weller-SP23LK-Marksman-Watt-Soldering/dp/B0009ZD2AG/ref=pd_sim_auto_1) or a station (http://www.amazon.com/Weller-WLC100-Soldering-Hobbyist-Yourselfer/dp/B000AS28UC)?)
Dave Hunter's Guitar Amp Handbook (http://www.buy.com/prod/the-guitar-amp-handbook/q/loc/106/31243267.html) (figure it'd be nice to have an onhand reference and to do some research)
??? I'm sure there's so much that I'm missing from here


Anyone have any thoughts/suggestions/critiques? Am I missing any crucial elements? Does this sound like a realistic place to start?

The firefly is a pretty cool amp, but without any tools now, maybe a bit much to start with if you do not go the PCB way. John's PCB and BOM make it a lot easier, but are not as modification friendly. The things I would do to start are use an ECC99 or 6H6N instead of a 12AU7 for the output and use something larger then a hammond 125A for the OT. This improves the bass a lot. I used a 125C because it was cheaper then the A or B. The 6H6n requires slightly different heater wiring. A low loss tone control like a Garnet could be added easely to the first triode after the cascode boost, but the PCB makes that more of a challange.

Tools: Good tools are expensive, but a joy to use, How much yoiu spend to start off with is really up to you.

DMM, check.

I would suggest just an iron to start off and more to a temp controled station if you find yourself building or repairing amps regularly. You will need solder, wire cutters and strippers, drill and bits to work your chassis

Thanks for the reply celeste.

So that multimeter does what I'd need? One review said that one function that is lacking is high range AC current (amps) the description says it measures AC current but doesn't say that the max AC amps it can test is 200mA or .2 amps, not really practical for ANY AC current measurments. Is this a big flaw? Also, I read another post saying that capacitance testing is a nice feature to have, would this Mastec unit (http://www.amazon.com/Mastech-Multimeter-Capacitance-Measurement-MS8261/dp/B000FLZDPG/ref=sr_1_1?ie=UTF8&s=hi&qid=1254089979&sr=8-1) be a better way to go? I'm totally willing to pony up an extra $8 for some useful features.

I do not really see a draw back being able to only measure 200ma ac for the kind of work you are talking about. In fact I do not remember the last time I had to measure ac current.

The other meter is nice, I have one for my spare. I got it free for an order over $60 from Circuit Specialists when I bought my soldering station. Capactience is nice for those times you can not remember the inscrutable cap codes.

Get a soldering station, the Hakko 936 is what I use and recommend. Good connections and solder joints are key to a trouble free amp build. Do a search for Terry Downs soldering guide here on tdpri.

My first DVM was an inexpensive one from rat shack, it worked flawlessly and lasted for years.

Anyone have other suggestions that would meet my goals?



Get a kit. That way you won't have to do the laborous tasks of drilling the metal chassis, or building the wooden cabinet. I mean, some people like doing that stuff, but to me the "amp building" part is all about soldering and component choices. Stick to popular tube choices...I would suggest an el84 amp (like a GA-5) or a 6v6 amp (like a Champ). Those type of single-ended amps would really grind at low volume levels.

Get a kit. That way you won't have to do the laborous tasks of drilling the metal chassis, or building the wooden cabinet. I mean, some people like doing that stuff, but to me the "amp building" part is all about soldering and component choices. Stick to popular tube choices...I would suggest an el84 amp (like a GA-5) or a 6v6 amp (like a Champ). Those type of single-ended amps would really grind at low volume levels.

Thanks for the suggestion? Can you recommend any that satisfy my requirements?

Low watt (1/2 - 4)
Good breakup
Minimal hum

Small footprint, gain/tone controls, boost switches, and wide tube computability range are also nice bonuses but not crucial.

I think the Firefly would be a good start. A Champ/Princeton might be easier because the components are bigger and spaced-out more, but with the Firefly you'll get the perfect output level. It'll make plenty of noise with an efficient speaker!

My 2x6AU6 amp puts out roughly 1 watt, and it's room-filling with a Celestion Blue.

- Scott