Suggestions for stereo amp to drive speakers, other than using demoboard?

Dan E

Hi,

I'm looking for an appropriate stereo amp to drive my speakers so that I can have audio for a school project, I thought about purchasing a MAX4411ETP chip, that is used in the demoboard, and build the rest of the circut, since purchasing the demoboard for just one purpose is expensive.

I tried searching for the MAX4411ETP headphone driver from other sites, but from what I found it seems that they are only sold in large quantities, and/or to vendors only.

Any suggestions other than purchasing a demoboard to drive my speakers?

Thank you,
Dan

schill

If you want to use the MAX4411, it's available in single-unit quantities from both Digikey and Mouser:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=MAX4411ETP%2B-ND

http://www.mouser.com/ProductDetail/Maxim-IC/MAX4411ETP+/?qs=1THa7WoU59Ewxk5VS3Cyvw%3d%3d

It's under $1.50.

Is this a package that you are comfortable working with?

You can also try requesting free samples from www.maximic.com .

Phil Pilgrim (PhiPi)

Amplified computer speakers are cheap and have good fidelity. Have you tried Best Buy?

-Phil

W9GFO

Phil Pilgrim (PhiPi) wrote: »

Amplified computer speakers are cheap and have good fidelity.

Would that work? Could you just hook up the speakers directly to the Propeller chip with no amplification?

Rich H

Phil Pilgrim (PhiPi)

Sure. PC speakers have built-in amplification. With a simple RC filter, the Prop can produce line-level audio, which is all the PC speakers require.

-Phil

jazzed

Phil Pilgrim (PhiPi) wrote: »

Sure. PC speakers have built-in amplification. With a simple RC filter, the Prop can produce line-level audio, which is all the PC speakers require.

Example circuit? I've found simple RC filtered outputs a little "edgy".

Dan E

schill wrote: »

If you want to use the MAX4411, it's available in single-unit quantities from both Digikey and Mouser:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=MAX4411ETP%2B-ND

http://www.mouser.com/ProductDetail/Maxim-IC/MAX4411ETP+/?qs=1THa7WoU59Ewxk5VS3Cyvw%3d%3d

It's under $1.50.

Is this a package that you are comfortable working with?

You can also try requesting free samples from www.maximic.com .

Thanks, just ordered from mouser, I'd prefer to use this chip since there is a known working schematic to use under the demoboard documentation link, and it's cheap.

Dan

Phil Pilgrim (PhiPi)

jazzed wrote:

Example circuit? I've found simple RC filtered outputs a little "edgy".

Okay, you made me test my pontificating! I hooked up a Propeller Backpack to an ancient pair of AST amplified speakers. The Backpack uses the following output circuit for each L/R channel:



I programmed in Chip's "Singing Monks" demo (with appropriate pin and clock modifications):

http://forums.parallax.com/showthread.php?89291-Singing-monk-squad

It sounded just fine! 'Don't know what else to say, except that it made me appreciate Chip's stereo spatializer software even more.

-Phil

jazzed

Wouldn't that selection of capacitors produce a skewed response curve rather than a bell curve? Do you have a graph of amplitude -vs- frequency?

Phil Pilgrim (PhiPi)

jazzed wrote:

Do you have a graph of amplitude -vs- frequency?

'Don't need one. My ears were satisfied!!

-Phil

jazzed

Sure, but your ears are even older than mine

Phil Pilgrim (PhiPi)

Be that as it may, I can still hear the TV horizontal sweep when the sound is muted ('missed Woodstock -- 'still have some hair cells). Of course, my TV may be older than you are, too!

-Phil

Rayman

I use the MAX4410 because it has a leaded package that is easier for me to work with. The downside is that it needs 4 external resistors (and is a bit bigger).

nglordi

Kye's wave player software and a simple RC circuit connected to powered computer speakers produces excellent sound fidelity equivalent to a cd player in my experience.

nickL