Hi!
I've found lots of LM386 simple amps, and almost all of them have some sort of gain or drive potenciometer.
But these amps have a rather small output, so I was looking for the TDA2003, that has a higher output and still can be run with 12v.
Problem is that all the TDA2003 designs I've found have no drive control...
Do you know any schematic for one?
Regards! :)
Download the excellent: http://www.vellemanusa.com/downloads/0/illustrated/illustrated_assembly_manual_k4001.pdf
For comments: http://www.ssguitar.com/index.php?topic=1834.0
Quote from: J M Fahey on December 08, 2010, 07:55:41 AM
Download the excellent: http://www.vellemanusa.com/downloads/0/illustrated/illustrated_assembly_manual_k4001.pdf
For comments: http://www.ssguitar.com/index.php?topic=1834.0
Hi J M Fahey... had been a so long time...
May i suggest to use at our friend a TDA2005? TDA2005 Datasheet (http://www.datasheetcatalog.org/datasheet2/0/00wzg9i6pe3jro24617pld9pyjcy.pdf)
It is practically the same effort to make and its twice the power of TDA2003.
I mounted a poweramp using the datasheet circuit, and it worked very good :tu: :tu: !!!
If is worried about controling the volume output, maybe you can copy the same concept of the illustrated_assembly_manual, i mean use a potentiometer conected as show, at the input.
Regards.
Quote from: J M Fahey on December 08, 2010, 07:55:41 AM
Download the excellent: http://www.vellemanusa.com/downloads/0/illustrated/illustrated_assembly_manual_k4001.pdf
For comments: http://www.ssguitar.com/index.php?topic=1834.0
Correct me if I'm wrong, but that doesn't have a gain/drive control either. With pretty much anything other than the little LM386, you will need to build a preamp to get your OD circuit.
It's a problem of nomencflature.
What 386 users call "drive", the pot between pins 1 and 8, is not so, but a simple *gain* control, going from 20 to 200.
Fact is, given the almost nonexistent headroom, it soon leads to distortion, simply by overdriving the power amp.
In the Velleman , you just use the input pot suggested as volume and (loud) overdrive *or* build an MXR Dist+ as a preamp and overdrive.
With Dist pot on "0" or a low value, it's a clean preamp (until the output signal reaches around 250mV RMS).