i need preamp schematics w/o tone control or volume control

[hernanstafe]

jut like the title says, i'm in need of a pream that just preamplificates the signal, meaning, that i don't need it to have tone control or volume control or anything, i just want the preamp part, anyone have such schematic?
thanks in advance!

 

[Minion]

Whay type of sources do you need to preamp?? How much Gain do you need?? Running off of a single or dual supply?? IC or discrete??

 

[hernanstafe]

well i the source is the headphones out of an mp3 player/ computer soundcard, etc, just that. how much gain? not sure...using a dual supply would be good, and i'd like it to be as simple as possible, IC would be good but idk if i can get good audio quality with that?

 

[Minion]

Well you Probably don"t need a preamp with a headphone output because the headphone output is allready preamped and has it"s own Volume controll as well as the Line out from a sound card is allready at line level so it"s doesn"t need to be Preamped....

Why do you think you need a preamp?? what is the output of the preramp going to be connected to??

Preamps are generally just used to Bring low level sources up to line level, Like microphones and Instruments ,The output of a MP3 player is probably above line level and so is the preamp in a PC sound card.....

 

[hernanstafe]

because i want some more power imput for the amp, i want to put something between the mp3 and the amp, i think the power ouput of the mp3 is not sufficient...

 

[theAnonymous1]

If you want something super simple to build, you can try a circuit like the "CMOY" headphone amp with appropriate gain.

http://headwize.com/projects/showfile.php?file=cmoy2_prj.htm

 

[Gordy]

Power amplifiers usually have quite high input impedances so they need very little current output from the source.

If the MP3 player has a volume control it might be fine directly into the power amp.

However, if you have long capacitive and / or you need more volume then perhaps you will need a pre-amplifier stage.

The 'CMOY' suggestion is sensible, and also take a look here...

http://sound.westhost.com/projects-2.htm
http://sound.westhost.com/projects.htm

 

[hernanstafe]

thanks a lot guys, yes CMOY looks pretty much what i was looking for since it's a really small and simple circuit. i'll try my amp with it and decide whether the preamp is needed or not, i think it is tho...