Extra power for low wattage amps. (1-5W or so)

[served]

Hi.

I am looking to add some power to these little mini amps. Ruby, Gem, Gem2, Cricket.
Some kind of amp stage, that would work with them all, well gem2 might be a problem, that I can use alone. I would like to add 2W or something. Not much, but a littlebit.
Is there a simple way to do it?
Maybe some kind of Fet stage or something?

I am a bit lost here, hope some one can help.


A.

[km-r]

basically, these small amps are powered and built on their "top" performance... if you want more power, you may try increasing the power supply. but the best way is to use a larger power IC. ive had this 2W utility amp before but i forgot the IC number [LM380 IIRC], its a 16pin IC where most of the center pins are ground. for 5-8watts an LM383 would be good.

[served]

Well yes and I like how they sound. But If I could just get them a little bit louder, I would be happy with the result.

[Gurner]

In all of those circuits you mention, swap the LM386 for a TDA7052 ...you've instantly doubled your power (it's a BTL....so give it the same power supply, output load & input signal - it'll give you double the power vs it's single ended oppostion).

It's not pin for pin compatible, but should take you all of 3 minutes to sort that aspect out! (you'll also save a few components as it needs less)

[served]

If I swap the op amps. Doesn't it affect the sound and remove the tricks that these pony's did?

[Gurner]

If I swap the op amps. Doesn't it affect the sound and remove the tricks that these pony's did?

the TDA7052 is not an opamp...it's an audio power amplifier. Like the LM386, it's purpose is to convert the audio signal into one that can drive an 8 ohm load. I doubt very much you'd hear any sound difference.

[earthtonesaudio]

Yep, if you want the same sound as the LM386, go for one of its bigger brothers like the LM380 or LM383.  The internal circuitry is mostly the same in this family, so the distortion sound will be similar. 

You can bridge pairs of these chips together for more power (and negate the need for decoupling on the output which results in more bass).  Check out National's AN-69 appnote for lots of suggestions for the LM380.

[petemoore]

A  Comparison of inneffecient and effecient speaker = not so loud to louder results. How stubborn or easy is the speaker?
b  Double what you have there, speaker and amp, make power consumption < power supply current rating of course. 
C  Re-do the power supply in order to move 'the rails' farther apart, consider split supply. Finding a suitable chip shouldn't be a problem [see data sheet for amp schematics], chips are a bit like a fancy switch-0 between the DC power supply and the speaker, as thrown by AC input voltage...ie they accurately reflect the power supply goodnesses or inadeqecies, if the PS is very good, a perfecly flat DC surface to the 'reservoir'...never gets breached, makes perfect mirror reflection of any moving input from below it's surface. 

[petemoore]

if the PS is very good, a perfecly flat DC surface to the 'reservoir'...never gets breached, makes perfect mirror reflection of any moving input from below it's surface.  
 Sorry for the mixed metaphors...but DC supply potential can be compared to a glass or pond of water. The amp syphoning water/pressure/current energy nearly synonamous with amp drawing current @ voltage X.
 Once the syphon tube breaches the surface of the water, a bunch of air gets in the current to the amp and messes with what'd otherwise be the steady pressure=DC, putting the amp to a slamming into off mode scenario [trying to exceed rail voltage makes it do that] when it'd normally still be pressing toward on.
  Start with the speaker, what amount of power supply will it take to drive the speaker without hitting a rail depends on:
  How loud it has to be.
  What kind of signal [bassy, trebly etc.]
  Volume settings [hit it with 'boost' and output current increases/it gets louder.
  How effecient is the speaker ?
  ...hard to tell, I always use the speaker watt rating and go by ear...analysis involves also experience attained after absorbing some Db ratings of speakers. The higher the DB number, the less amplifier prepared currents it turns into heat = the more effecient it is.
  So we don't know.
  we figure 10w is 'loud', 20w is a little louder, 30w pretty much gets the lions share of tone Vs. volume from a greenback, a common and very good compromise [they're all compromises].
  At 10w, we're well above what most wall warts or ''easy'' will suffice for, we've either had it magically done
  [http://www.parts-express.com/pe/showdetl.cfm?Partnumber=120-532
  which is pretty good deal considering I haven't wanted the 5amp unit yet],
...or worked out:
  http://geofex.com/Article_Folders/Power-supplies/powersup.htm
  Linear Power supply involves mains, chassis, IEC, Rectification, Filtering, regulation.
  Some threads about switch mode and SMPSupply popularity have popped up recently. Apparently good cheap power as long as they're not whining. I preferred linear supplies though.