> With all the discussion going on about this amp, I thought
> I'd post my
> review that I put on the net several months ago:
I hope you don't take offense at this, but.......some
comments about your review:
1.) That amp is not a switching mode amplifier, and not
being switch mode it can't possibly have 80% efficiency.You
must have had a serious metering or math error.
2.) I looked at the circuit, and there is not special about
it at all. All that stuff about "flywheels" is just
nonsense. It is a regular push-pull amplifier with forward
bias, it is simply a traditional class AB amplifier driving
a regular old lowpass filter.
3.) With an unresolved metering problem we can't be assured
the transfer function data is reliable.
4.) On the air reports are next to meaningless. People can't
"hear" the distortion of a class C amp on frequency unless
it is terribly bad. We don't really know how clean the amp
is by anything you wrote.
Things like this trouble me. It is VERY easy to get an amp
type accepted if it complies with rules. It is inexpensive.
It is also very plain that amp would never pass FCC TA
requirements, so that is almost certainly why they didn't
apply for TA and sell legally. E-Ham is absolutely correct,
it is an illegal amp.
When I see a large company selling things into the market
via the backdoor and reviews that very clearly have serious
mistakes helping steer their products into use, I don't get
a warm feeling. I think we are heading down the wrong path.
I'd be happy to measure and post the actual IM3 and IM5
specs and efficiency of that amplifier, measured with up to
date currently certified test gear, at no cost to you. If it
looks good, we should all endorse it. As it is right now,
very little in your review makes sense. There is no such
thing a "flywheel" that cures IM distortion, the efficiency
can't possibly be 80% since that is beyond the theoretical
limit of a perfect lossless AB amplifier and nearly twice
what a solid state 12V amp will typically do, and there is
nothing reliable that tells us it passes harmonic tests or
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