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TDA2030 amp

Started by lavejim1, July 11, 2014, 01:10:11 PM

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lavejim1

Hi guys. I haven't been on this forum for awhile.  I ended up with a few tda2030 amps and would like to build a small amp from them,  no bridge config, just a single chip.  Have looked at some here, but they all seem to have operational problems.  Can anyone suggest a tested circuit??  Thanks in advance...keep building!!

Enzo

What operational problems?  In what circuits?   The TDA2030/2040/2050 has been around a long time and there are millions of them in amps all over..   There is not a part made of any kind that cannot fail.  people write in with a blown TDA2030 now and then, but with millions of them out there, that will happen.

Look up the data sheet, there is a basic circuit on it, and that works.  it is just a power amp in a chip.

lavejim1

Thanks, no need to get testy, give the noob a break

Enzo

I am sorry if I gave that impression.   I was just asking the question:  to what operational problems do you refer, and what amp models might be affected.   As a technician, I am not aware of any problems with this line of parts, they are widely used.  I am not being snippy, I just want to know where that impression comes from.  And unless I know what you mean, I can't respond in meaningful fashion.

The last thing I am is hard on newbies, I do like to be direct though.  I am a patient man and am happy to help anyone learn who is willing.

All those smaller amps from every line - Marshall, Fender, Peavey, Crate, etc, etc. - the little 15 watt amps, they all use this IC, and none of them are unreliable for it.  Those amps fail, but so do any other, and the failures are usually things like jacks and controls.


What do you intend to build?  I was not joking about the data sheet.  If all you want is a power amp, the circuit on the sheet will work, just add a power supply.  But i assume you have in mind a complete amp, including preamp.   Examples would be most anything with 15 in the model name.

J M Fahey

Quotebut they all seem to have operational problems.
All?   :o
Quote
Can anyone suggest a tested circuit??
Yes, the suggested one in the datasheet.
What everybody uses, by the way.
4 resistors, a couple capacitors, simple and effective, why reinvent the wheel?

lavejim1

OK, thanks...I do have the schematic in the datasheet, and have found a good pre-amp circuit. This will be a small amp, I intend to use a single 24 volt supply, should give me 8 watts or so into 8 ohms.  If I get it built and get the bugs out, I will post.  Thanks again

Bajaguy

One thing to keep in mind when you are matching a preamp to a chip amp is matching the input impedance of the chip and the output impedance of the preamp. Not paying attention to this will cause some nasty oscillations...... ask me how I know. :grr

Baja

Loudthud

Quote from: Bajaguy on July 28, 2014, 11:40:20 AM
One thing to keep in mind when you are matching a preamp to a chip amp is matching the input impedance of the chip and the output impedance of the preamp. Not paying attention to this will cause some nasty oscillations...... ask me how I know. :grr

Ok, how do you know this? Were you exceeding the input common mode range of the chip? Looking at the ST data sheet for the TDA2030A, the input common mode range is not specified. Ill bet strange things happen when you slam the input rail to rail or try to operate with a non-inverting gain of one.

Roly

Quote from: lavejim1have found a good pre-amp circuit

{Why am I filled with a dark foreboding?  What are the odds of lotsa trimpots?}
If you say theory and practice don't agree you haven't applied enough theory.

JHow

It's not a scientific survey, but I have worked on a number of the little fender r15s, and I would say broken jacks are way more common failure than output device.  I think little amps on the floor get kicked around a lot easier, also dropped.  If you trip on a JC120, you might hurt your toe but if you kick over a little frontman, the guitar plug can act like a lever and break the jack or even crack the PCB.  Also, for what they are, I think those frontmans sound pretty decent, especially if you put it into larger speakers than the 8" it comes with.  The preamp might be more complicated than you are looking for since it has a tone stack and distortion stage, but its basically two chips some pots and various R and C.


Sent from my iPhone using Tapatalk

Roly

Quote from: JHowIt's not a scientific survey, but I have worked on a number of the little fender r15s, and I would say broken jacks are way more common failure than output device.

By a fair margin.  This great-leap-backwards style of direct-on-PCB mount socket with no panel nut or other support than the solder joints turn up all over the show, guitar amps, synths/pianos, stomp boxes, and they are all fragile to normal abuse.

In my day were were taught make a physical joint first and "not to rely on solder for physical strength", and these sockets demonstrate the truth of that rule, all for a few cents "saved".

That said, 6.5mm hardware for guitar amps was never up to the task, XLR's are far better where you can use them.
If you say theory and practice don't agree you haven't applied enough theory.

J M Fahey

Agree.
Most 15W beginner amps in fact are quite good, plagued by too cheap speakers mounted in shoeboxes.
You plug them in "real"  cabinets and ... wow !!!!
Search Youtube for examples, specially the puny 1W 9V battery powered "Smokey Amp"  plugges into a Marshall 4x12"
That amp does not even have knobs (incredible, not even a volume knob  :o ) !!!!!!!!!

http://youtu.be/1KSWa7N1xGY

Mind you, it has no knobs but it has Tremolo, Wah wah and Leslie !!!
Just watch this crazy video:

https://www.youtube.com/watch?v=RileBbu6Gyc

and he forgot one extra effect: Reverb !!!!

just put it in the floor of a large tiled room and wail away ;)