Those little smokey amps

[BodomHatecrew666]

Hey guys has anyone build one of those little portable (battery powered)amps that come in the size of a pack of smokes. I thought it is a real cool idea for when ur out at the lake or somewhere u cant bring a big amp (sitting on the beach) i like the idea and was wondering if there are any schematics for these or others similar or even something a little more power but portable i want something small and very portable with a nice sound with or without effects plugged in ( i would like to use distortion but am not sure if it would sound good out of a little speaker)
well any suggestions would be cool or if u could send me in the right direction that would help..

[cd]

It's a cookbook LM386 circuit.

[thumposaurus]

Take a look at the little gem over at runoffgroove http://www.runoffgroove.com/littlegem.html
I've got one I built in an altoids tin with just an on/off switch, simple easy build.

[BodomHatecrew666]

cool ill check it out

[Peter Snowberg]

386 amps are lots of fun but to get the full effect I would suggest one with a high impedancwe buffer in front like the http://www.runoffgroove.com/ruby.html .

[BodomHatecrew666]

yeah i  like the look of the ruby look and seem like its what i am looking for..

[Peter Snowberg]

Best of luck on your build!

Try out a variety of speakers of you can. It might sound OK with a 5 inch, cheesey and soft with a 3 inch and awesome & loud with a 10 inch speaker. There's a LOT of variation. Oh also...... if you add a 500 ohm pot in series with the speaker you can dial it from loud down to whisper quiet with a 12 inch guitar speaker.

There are also a couple of different chip geometries from a couple of makers. May favorite version is the JRC386BD. Second favorite is the LM386-4. Both of those will handle 18 volt supplies.

The next best is the LM386-3, and then come the low voltage chips like the LM386-1 and the JRC386D.

There is/was also a GL386 from Goldstar that I have never heard.

Have fun!

[william]

Whats the best way to get a clean type tone from a 386?  When I tried it I couldn't get the amp to be very clean on its own.  I'd like to use two 386's and a single speaker for a small power amp for late night practicing.  I have a few tube pre-amps I'd like to use with it, but I want a little power amp distortion as possible.

[ED]

stay clear of the 386-1!!!!!!!!!!!! It's really quiet and goes into harsh clipping that sounds really bad when notes picked hard.

when i replaced it with a 386-4 it is now twice as loud, and sounds MUCH better. nice and clean almost the entire way up the volume knob until the top where nice overdrive takes hold.

Here in Australia there is not much choice in these chips from local shops as far as i know, so i dont know about any of the JRC models. everyone seems to think they are the way to go.

I use mine with a minature quad box i built (4 X 2" speakers).

ED

[remmelt]

i have a smokey amp. it is a lot of fun! the guitar volume acts like a non-master volume knob, so it goes louder and the gain goes up as well.

it doesn't really go clean at all, unless the battery is REALLY fresh and i have my volume down to about 5 (strat w/hi-pass filter mod, kinman avn blues pickups).

the downside is, this lil amp doesn't like effects at all. the npn boost boosts it out of usable range even when on low. distortions and fuzzes are no better. i think the amp is already cranked, so to say. it just stops playing for a second, then comes back when it stops overloading (is that what you call 'gating'?).

the best time i have with it is when i plug the 2x12" greenbacks that are part of my bluesbreaker in it. the sound is amazingly loud and punchy and nice and warm. it does eat batteries that way though.

it was kind of expensive (i paid 70â,¬ at sacksioni in amsterdam.) but it gets a lot of playtime so i'm happy. the box is getting jagged at the edges, but that only adds to the mojo

[RDV]

stay clear of the 386-1!!!!!!!!!!!! It's really quiet and goes into harsh clipping that sounds really bad when notes picked hard.

That one works fine for a headphone amp though.

RDV

[RDV]

Whats the best way to get a clean type tone from a 386?  When I tried it I couldn't get the amp to be very clean on its own.  I'd like to use two 386's and a single speaker for a small power amp for late night practicing.  I have a few tube pre-amps I'd like to use with it, but I want a little power amp distortion as possible.

Build a Ruby and don't connect pins 1 & 8 in any way. That's about as clean as things get with a 386. They're not a clean chip by nature. When you start driving it with a preamp, it'll start distorting on it's own if you feed it much juice at all.

RDV

[smoguzbenjamin]

Whats the best way to get a clean type tone from a 386? When I tried it I couldn't get the amp to be very clean on its own.

To decrease distortion with a 386 chip, add a series resistor to the input, that'll result in a lot less distortion and very little volume loss.

[Ansil]

actually theres an easy way. use negative feedback to limit the distortion.

works for me.