High Power Chip Amp

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Does that make me a bad person?

As little as star882's class D devotion makes him a bad person. The important thing is not to forget that many ways lead to Rome. And that starters should do starter projects like chipamps and leave solid state and class D for later, when they either acquired the adequate knowledge or the insight that everything is not as simple as a three-resistor-amp.

When I see all the threads discussing the necessity of Zobel networks and DC blocking capacitors, I wonder what the same people would make of all the inductors and capacitors in a class D amplifier. There are numerous threads showing that people don't just want to copy a manufacturer's reference project, but how promising could an attempt at designing their own class D PCBs be?
 
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And that starters should do starter projects like chipamps

I'd like to see you tell that to the engineers at Jeff Rowland!!:spin: In my case it's another type of amplifier I haven't built and tested and it has many promising aspects... I'm just not interested in the peanut power a single chip affords. Aside from soldering does building a small chip amp really teach an aspiring audio enthusiast anything... very doubtful actually. There are other uncomplicated, more useful audio projects that an aspiring builder would get more from.

So in about 40 years of building audio stuff I very definately haven't checked out all the ways to Rome, especially if If Star doesn't point me to a worthy Class D project... I have however checked out all the ways to get to the Tetons and not too many can claim that!

Mark
 
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Now to get this thread back on track... Has anyone out there tried an SMPS type supply on this 300 watt amp? There are several available that provide near the correct operating voltages and they certainly are the power supply of today. I've installed a load of QSC DCM series power amps over the years that utilize SMPS supplies and they sound fantastic and have an excellent track record.

Mark
 
... Has anyone out there tried an SMPS type supply on this 300 watt amp?
before you ask about a design, maybe you need to think about the brief and then the specification.

The brief will short list the needed attributes. eg, power, impedance, supply voltage and maybe cost.

The specification will start with the current that a real speaker will demand when trying to reach that 300W target from a standing start.
 
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I run a Dynaudio BM6 passive monitor pair off a paralleled (2x) LM3886 chipamp, but these are nearfield monitors. Anyhow, it drives them loud enough even in far field, no distortion, clipping, or nasties, and enough power to push the woofers into destruction (though I didn't go that loud).

That amp has moved on to a new owner, and I'm still wondering what to build for them. For now they have a single 3886 doing temp duty, and apart from SPiKE kicking in at high levels and the chips running a bit hotter it's all fine. Dynes seem to like amps with plenty of current reserve, and their low sensitivity calls for high voltage as well. Two chips is threshold minimum, I'd be happier with 3.

Or, as Andrew suggests, hybrid discrete, or even fully discrete. That would eventually be a more appropriate solution for Dynes. We were talking about it on another forum and for the same reason we concluded that most budget home-theater receivers would not be able to drive any kind of Dynaudio. Those speakers call for quality amplification. I don't know that they always do it justice, but that's another topic altogether...
 
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And that starters should do starter projects like chipamps
I'd like to see you tell that to the engineers at Jeff Rowland!!:spin:

Bridged-parallel amplifiers do not qualify as starter projects, even if starters sometimes achieve satisfying results with them. The right way is to start with a single chipamp and learn, what it can do and how, before you group several together. Jeff Rowland and his engineers did not simply connect a bunch of datasheet applications together. Their secret lies in everything that is around the ICs, like power supply, input transformer, component choice, layout, etc. It would certainly be interesting to compare some of the BPA projects with a Rowland amplifier and see, if it is really so easy to achieve the same result.


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Aside from soldering does building a small chip amp really teach an aspiring audio enthusiast anything[/QUOTE]

Depends on the enthusiast whether it does, but at least it has the potential to teach a beginner,
- what AC coupling and DC coupling are, and why one is preferable over the other.
- how to build a power supply.
- how to avoid ground loops.
- how to choose RF filters.
- how to choose the DC blocking caps or the DC servo plus DC protection.
- which protection systems are necessary.
- why heatsinks are needed and how big they must be.
- whether the "peanut power a single chip affords" is sufficient for his demands or not.
- if swapping components like capacitors for others improves the sound and how.
- how to mechanically lay out an amplifier so that different signals don't couple into each other.
- how little you gain with a better or more powerful amplifier, when you compare it to the gain you get from better speakers.
- etc.
 
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