[rafaelkl]

Hi, I'm new here, so I'm sorry if I'm posting on the wrong place.
 
I want to make a headphone amplifier, dual channel,  to plug in directly an instrument, like a guitar or bass, and a line signal on the other.
 
On my searches I found the LM4880 from Texas Instrument, but searching on the forum I found that it isn't a good chip.
 
I'd like some recomendations of which IC's I could use. It must be SMD (possible to hand solder), stereo and work with 3.7V (since I'm gonna make it rechargeable with a Li-ion cell).
 
I'd like it to be loud, since I intend to use on the band stage.
 
If i forgot some information, please let me know.
 
Thanks for the help!!!

 

[Avro_Arrow]

 
3.7 volts is not going to be enough.

Consider changing to two li-ion cells or
eight to ten NiHM cells.
 
This link will help get you started.

 

[rafaelkl]

Thanks Avro_Arrow,
 
I thought 3.7 V wasn't gonna be enough, but since my cell phone is supplied with 3.7 V and have a good sound...
 
Also I read somewhere here on the forum that 200 mW is enough to blow your ears, and on the IC datasheet they say that with about 3.5V we could take the 200 mW.
 
I will take a read on the link.
 
Thanks again!

 

[Avro_Arrow]

What heaphones/IEM are you using on stage?

 

[Avro_Arrow]

 
I want to make a headphone amplifier, dual channel,  to plug in directly an instrument, like a guitar or bass, and a line signal on the other.

It would stick to taking your source from the mixing board. Taking a signal from the guitar would require another level of amplification.
A wireless pack would be the best solution, but expensive.

 

[rafaelkl]

I wanna do it for my entire band, one for each person.
 
I could take it from the mixer. But what I intend is also make it for jams and training. Example: Just plug in the bass on one channel, and a signal from the cell phone, laptop or mixer on the other and play. We will probably use some cheap headphones like the Koss Porta Pro.
 
I was thinking now and maybe the project isn't really this forum focus, which I believe is a hi-fi quality.
I don't really need a Hi-fi quality, just an acceptable.
 
Edit: Since I want to make it as compact as possible, another battery will disturb. But in last case...
 
Thanks for the help!

 

[nikongod]

There should be room for something like this in the tightest of guitar bags. Compared to the size of a guitar an amp like this is tiny.... If you plan well the whole thing (with 2x9V) can easily clip onto the guitar strap. 
 
That being said, I'm not too familiar with these sorts of things, check out "guitar practice amps" but I found this with a search of "guitar headphone amps"
http://www.miccastore.com/fiio-g01-portable-guitar-headphone-amplifier-blackred-p-90.html
 
There are sure to be tons more.