Need suggestions for basic chip amp kit

[percy]

Hi, glad to find a forum for "Chip Amps"!
I want to quickly build a small amp for use with "Speaker Workshop". Its a software that uses your sound card to measure impedance and acoustic response of a speaker.

Power is not critical - I believe 5-10W should be MORE than enough - but the amp should have pretty good noise/distortion figures and frequency response. (Noise better than -80-85db , THD/IMD better than 0.1%, ideally 20hz-20Khz response). I looked around for some kits and this by far is the best I could find for the price - Its a Vellemann kit (K4001) based on the TDA2003.

http://www.audioxpress.com/bksprods/kits/kv-k4001.htm
http://www.partsexpress.com/pe/showd...number=320-214

Budget is a constraint and I dont want to go much higher than what these kits are going for.

Any other suggestions or better alternatives ?
Thanks!

[chipco3434]

Run for your life before the addiction is too strong to fight...

Otherwise, see

BrianGT's NI GainClone

I just ordered parts for my third one. Haven't fired up the Adcoms in months!

Simple, inexpensive, top quality sound.

[percy]

I am sure it must be a very nice amp. However, one thing I have noticed - you have to be careful with these little chip amps is that even though the 'core' schematic looks so simple and innocent, the power supply is usually a monster and eats up all your budget. No doubt its a very important part of the completed amp, but defeats the purpose for me.
I want something more simple that can run off my single 12VDC 2A wall transformer or a battery put together.
Secondly, it doesnt matter how it sounds or what type of tonal characteristics it has as long as it has decent noise, distortion and frequency response figures. I will almost never use it for music, only measurements.

[carlmart]

Originally posted by percy
I am sure it must be a very nice amp. However, one thing I have noticed - you have to be careful with these little chip amps is that even though the 'core' schematic looks so simple and innocent, the power supply is usually a monster and eats up all your budget. No doubt its a very important part of the completed amp, but defeats the purpose for me.
I want something more simple that can run off my single 12VDC 2A wall transformer or a battery put together.
Secondly, it doesnt matter how it sounds or what type of tonal characteristics it has as long as it has decent noise, distortion and frequency response figures. I will almost never use it for music, only measurements.

The restraints you are putting for your project seem a little hard.

To start with there's not much you can get from a 12V/2A supply, particularly if they are wall transformers. Most quality chips work with a split supply, so you will have to get a doubler circuit on line or use a DC-DC supply to get more power. That will also cut your amps.

There are some old chips, like the TDA2003, that did work on a car's voltage only, and you could get about 6W on 4 ohms. But distortion figures and noise were not that good. That power is also for a 14.4v supply, which is what you have on a running car.

http://www.ben.cz/download/121098/tda2003.pdf

You can bridge two of them, to get more power and eliminate the obligatory output series capacitor, but you won't get too much. Perhaps 10W into 8 ohms. Worst distortion figures too.

In the end you might be better served by a more modern chip, like an LM1876.

But you should think different and discard the wall supply.

Just my opinion.


Carlos

[Mr Evil]

If you're worried about the cost of the PSU, pick up an old stereo from a car boot sale or wherever. You should be able to pull out enough for a complete PSU from one: transformer, rectifiers, reservoir capacitors, even connectors, switches fuses etc.

[mrskinny]

Here's something you might want to try- www.si-5.com Look under " all products", then Class T amp. Good sounding amp,15w/ch,will run off 8 AA batteries or 12V wall wart. They list it as retailing for $39,but if you do a search on Google,you will find them for around the $20 mark.Might be just what you are looking for.