Burning up input?

[magudaman]

I just started to get into building amps and started with at kit for a 18 watt Hitachi HA13118. I am making the whole set up run on 8 AA batteries making it very portable. I used a DC-DC converter to boost and hold my voltage 18v so I can get the 10 watts rms. What I want to know is: this amp is made (according to them) for low input stuff but I want to pump in the headphone output from my Creative Nomad Jukebox Zen Xtra mp3 player. According to the specifications of the amp it wants an input of : <25 mV, for full out put; G> 50 dB. The Nomad as far as I can tell can put out more than that specification wise. For the Nomad it say 100 milli-watts and ive seen number like 100 db output. Can I damage the amp by running to high of an input...will it start to audibly distort when I do run to much in so I can know. Lastly how do I know or can figure out how many Milli-volt my mp3 player puts out (i have a fancy volt meter). Any answers would be much appreciated

[magudaman]

If there is some part of the question you do not understand please let me know or if you need some sort of information pertaining to the question leave a post and I will answer I would like to get this problem figured out. Thanks

[demogorgon]

I'm not familiar with the chip in question here, but most chip amps revolves around power opamps, at least those i'v seen.

and so, the maimum input can really be as high as you want to, maxing out at the rail suply (+-18V), but you usally dont have such a high output source, so thats why you set a higher gain on the opamp itself and\or play oround with input impedance. (not sugested though..)

make of my reply what you want, maby i didn't help, maby i did.

any links to this kit so we can get some more info in the amp? might help a litle..

[tiroth]

The answer is yes, the amp will audibly distort if you overdrive it. You should not have to worry about having "too much" gain in terms of damage.

With 50dB of gain it will be quite noisy though.

[magudaman]

It is pretty noisy at 50db but I'll live with it...I believe you answered my question...it really doesn’t matter what I run into the unit (well low power stuff) if it audibly distorting I’m basically running too much power in. As for a site with the kit on it, this ones pretty good because it has the PDF with lots of info. THANKS GUYS!