cigar box amp - power and grounding question

[uncledave]

I am building another cigar box amplifier, using a 2.5W Artec amp circuit, an Artec QDD2 Quadra Distortion Driver circuit (both from C.B. Gitty), and possibly a 9v slapback delay circuit of some sort (yet to be determined).

See my diagrams below (and I apologize in advance for my lack of electronics knowledge and poor schematic drawing skills).

I would ideally like to use a single 9V battery to power everything, and have everything on a common ground, as in drawing "A". I have a feeling that this is too easy and simplistic to actually work. Would it?

If not, would I have to use three different 9V batteries, as in drawing "B"? And, will this work as drawn, using a common ground bus?

The $64,000 question: if neither of these layouts would work, then what am I doing wrong, and how can I do it correctly and efficiently?

Remember, I have the mind of a child, so please respond accordingly.

[img:900:632]http://www.davedycus.com/cba/a.jpg[/img]

[img:900:626]http://www.davedycus.com/cba/b.jpg[/img]

[M Fowler]

I used to use a LM380 IC for small amps but now days I prefer tube amps.

Mark

[epis]

Hi Mark, your article is cool, but I wouldn't recommend to anybody to build that type of amps, no power transformer is NO - NO.

"Remember, I have the mind of a child, so please respond accordingly." - said uncledave.

[M Fowler]

Hi Mark, your article is cool, but I wouldn't recommend to anybody to build that type of amps, no power transformer is NO - NO.

"Remember, I have the mind of a child, so please respond accordingly." - said uncledave.

I agree it will need an isolation transformer or just build a champ.

Mark

[Structo]

I knew there were cigar box guitars but didn't know about the amps.

Pretty cool someone is capitalizing on it.

[Andy Le Blanc]

you can use a couple of 12v PT and voltage doubler to get the heater v and then bump it back up to around 200-250 v, still keeping it in a small package

those little moonlite designs with the self split 12au7 are very simple, would fit into a very small box as well

distortion can be 4 extra diodes, one cap and switch around one 12ax7 I bet you can meet your original design goals with tubes.

[boots]

My 8 year old son and I recently threw together a small amp that fits in an Altoids can. It ain't pretty, but it works great. We put an external speaker in an almond can.

The amp is just a 386 op amp from Radio Shack. We used an example circuit from the data sheet. It runs off a 9V battery (or solar panels!). It puts out about a half watt, and it is loud enough to irritate my wife in the next room. It is a very dirty, distorted, warm sounding amp, and plugged into my 8" Weber AlNiCo speaker, it sounds pretty big.

Fun, easy little project with minimal parts.

[boots]

To answer your question uncledave, I don't see why you would need 3 separate batteries. I think a single battery could power everything, as long as it supplies enough juice. A single ground bus and single power bus would probably be fine for a solid state project like that.