Help for a newbie?

[mtrout]

I posted this in the introductions forum, but it's not going to get many responses there, so I'm asking here:

Hello! I am new to this site and am finding the info here very interesting. I am a hunter and fisherman from Michigan looking to build a coyoter caller. I need an amp that will accept the input from my Sansa mp3 player and output to a 50w bullhorn style speaker. I got this idea here:

http://www.varmintal.com/ahunt.htm#El-Cheapo

What I don't like is the cheap 9v powered RadioHack miniamp, I know I can do better!

I've been pouring over a lot of information on this sight for the last few days and have yet to find the solution for what I would like to do. I don't need top notch sound quality, but what I do need is volume! So can anyone help me out with suggestions for an amp or suggestions on where to start? I was thinking a simple chipamp might do, but which one? What about a gainclone? I have already tried some powered computer speakers, but they are not loud enough and have a lot of hissing and static when the volume is turned up.

Help!

[sansbury]

I'm a newbie too but the battery-powered T-amp by Sonic Impact may be what you're looking for. Google and ye shall find. Have no idea how well it would drive that speaker but the amps themselves get nothing but praise and can be had for about $40.

[mtrout]

Thank you Sansbury, I will check out that amp. I am still hoping to build something myself rather than buy one. As I heard someone else on here say "where's the fun in that". If anyone else has any suggestion I sure would like to hear them. I see many possibilities and I am just not sure what will do the job.

[Arx]

What do you plan on using for a power supply?

If you need it battery powered, you may not have much luck with the amps people are building around here. Most of them run best with +- 30ish volts.

You might be able to do something with one of the smaller chips like the lm386, but that's likely along the same lines as what's in your cheap computer speakers.

If you need any large amount of power, you're going to need a power supply with some voltage boost.

-Nick

[gofar99]

Greetings, I find it much more rewarding to build something vs buy it. But occasionally reality sets in and commercial stuff can be a better option. Two thoughts come to mind on your intended use. The SI T amp has some merit. It is designed to accept MP3 signals and runs on AA batteries. It will run all day at modest levels. It is stereo and I don't believe it is easily brigable (some else might know how). Maybe you can use two speakers. A project using the T is on the Parts Express web site. Lot's of good info there and it may give you some ideas. My second thought is why not go get an amp designed for vehicle use. They come in all sizes and will run fine on 12 volts. Use a large gel cell and feed the amp direct from the MP3. It probably will have plenty of drive for the amp. Plus the amps come in mono versions. As mentioned in another post, big amps require big power. My personal preference is the T amp. If you are stuck out in the woods and the gel cells die you are out of luck. With a T, you can stick in another bunch of batteries. (The Ts BTW run fine on 12 volts too. Hope this helps.

Good listening
gofar99