bass version of smokey amp possible?

[SirPoonga]

My friend bought a smokey amp for his les paul guitar.  It sounds awesome for such a small speaker.  I like the portable idea.  I was wondering if such an amp, or related amps like the little gem, could work for bass.  

What speaker would be good for something portable?  I have access to 6" 8 ohm speakers.  Not sure how well they would work.  I know 6" is about as small as you can get to get any type of bass out of a speaker.  I know the subwoofers in laptops are 6" but are mainly designed to feel the bass than hear it.  Could you drive a speaker for a project like this off a 9v battery and get decent play times?

Edit:
Is a Fender Bassman a bass amp?  As mentioned here
http://www.runoffgroove.com/ruby.html

Actually, I was going to make this headphone amp and it uses the same amp chip as the Ruby.  how would they differ?  Could I just make the headphone amp into a smokey amp type thing?  Again, what speaker should I use?
http://headwize.com/projects/showfile.php?file=guitar_prj.htm

[Nasse]

http://www.tone-lizard.com/LESSON_INDEX.htm

Some talk about Fender Bassman and some other legendary gear (lesson five)

I believe some small speakers that go low and "hifi" subwoofers are not very efficient...

I bought used Ibanez solid state bass practice amp at flea market very cheap, it has 6" speaker. It is closed-back cabinet for more bass

[SirPoonga]

Right.  I guess I am going to have to dig out my DIY speaker book and try finding a speaker with good specs.  Good thing with bass, making a closed box is smaller than a ported enclosure.

Anyway, what I am trying to get after is could I make a portable amp like the smokey that would work.  And the biggest part holding that idea back is finding a speaker.


Actually, how is the smokey amp switching between the speaker and the output port?  I know it is probably a normally closed jack, but is the speaker getting the same signal as the output jack?

I'm not looking to drive a cabinet like you can do with the smokey amp.  What I'd really like is a headphone amp with the alternative to play out of a built in speaker, like the smokey amp does.

[SirPoonga]

Interesting.  I was visiting a friend this weekend.  He plugged my bass into his Fender MA-10 mini-amp.  That has a 3" speaker.  amazingly it was producing the bass witht he same volume as his guitar.  E and F were just starting to die down in volume.  So if I had a 5 string I doubt it could handle it.

I'm thinking of trying to make a smokey amp type of thing with a 4" or 5" speaker.  Maybe 6".

[MartyMart]

You could try the "Ruby" amp at www.runoffgroove.com
There's a "Bassman" setup for it, and just using larger input/output caps should do it !
You'll need to connect to a larger speaker though !

Marty.

[the_badcliff]

>Actually, how is the smokey amp switching between the speaker and the output port? I know it is probably a normally closed jack, but is the speaker getting the same signal as the output jack?



Heres the switchcraft 12A, which I used to add a speaker output to the Ruby/Little Gem hybrid I built.  Connect the tip to the output of the LM386, as usual.  Connect the ring to ground, once again, as usual.

Connect the NC to the positive lug of the built in speaker, and connect the negative lug of the speaker to ground.  Without a cable plugged in, the NC is making contact with the tip, and the built in speaker is being driven.  When a cable is plugged in, the NC is not connected, therefore the built in speaker is turned off, and the circuit will drive your headphones or whatever you happened to plug in.

I've never actually used a Ruby with headphones, but it gets plenty loud driving my speaker cabinet.

[the_badcliff]

sorry, I guess I didn't really answer your question about the smokey amp.  I have no idea how they do it, but I sure don't know of any other way.

[SirPoonga]

I have the right jack to do that.  The ones, errr, forgot screen name, is selling in the for sale section.  All three lugs have a NC and NO pin.  When the jack is inserted it breaks the circuit.

Ok, I think I am going to try something.  I think I will go with the ruby amp with bassman mods.  There's a 8" pioneer surround woofer at Radioshack with specs that say it should get pretty low.  I haven't been able to find a <8" speaker that can get as low as needed for 5 string bass (I plan on getting a 5 string sometime).  It won't be as portable as a smokey amp but it won't be too large either.  I have to run the speaker specs through my box caluclations and see what size of enclosure the speaker needs to be in vs what I want.  Either way, I doubt the box is going to have to be much bigger than the speaker.  The electronics and battery cna fit in the dead spaces around the speaker.

I'm going to try some interesting mods so it does what I want.
1) Uutput (if a jack is inserted no sound out of speaker)
 a) Headphone jack (in stereo of course)
 b) Amp output (like the smokey amp)
 c) speaker output
2) Using the control knobs from the Ruby design
3) Effects in and out.  I plan on making a couple of small effects that clip onto my strap.  Maybe, instead, I will make a box with velcro on it and velcro the effects and mini amp together.
4) Aux in (for mp3/cd player) (will only work with headphones)

For 4) can I just use an audio pot to control the volume and output directly to the headphone jack?  I know I could control volume on the player, it'd just be nice if all the controls were on one box.  I am tempted to just get a Y cable instead though.

The goal of this project is to have my ultimate travel mini-amp.

[Ge_Whiz]

You're going to have one hell of a job fitting that 8" woofer in a cigarette packet.  :lol:

[SirPoonga]

yeah, I'm just planning on making something as small as possible.  I've been hunting speakers for some time.

Now, that 3" speaker in the smokey amp can not handle bass, I've tried that.  The 3" in the Fender MA-10 can handle a 4 string, I doubt a 5.
I haven't found anything, at least reading the spec sheets, below 8" that can handle 5 string bass well.

so I'm just going to make it as small as possible.