the end of the world. There are
holes for power leads for a hard-wired application in parallel with
the power jack, too.
At first glance, this one looks
like it should dissipate heat a bit
better than the other TA2024
module. There's a large thermal pad on the bottom of the
board — even some traces on the top are designed for
dissipating additional heat — but it only has one onboard
filter capacitor; the rest of the components (except for the
output filter inductors) are all surface-mount (Photo 21).
Since it's based on the same chip as the other TA2024
module, it will have the same maximum ratings. This one
didn't quite measure all the way up to spec, but I'd be
comfortable recommending it for more ambient
applications where volume and packaging are more
important than sound quality.
Distortion rises steadily — although not too quickly —
up to 11.4% THD+N at full rated power into a four ohm
load, but through much of the range there's little to no
background hiss which makes the sound much cleaner
overall (Photo 22). That's right where the datasheet says it
should be in the end, although it is supposed to be mostly
clean and flat until the high end of its power bandwidth.
Like its connector-less cousin, this one also went into
cutoff when running at high power for several minutes, but
since that's not really likely to happen in most real world
applications, it isn't a huge problem. Again, a heatsink
should clear that right up. It doesn't sound terrible, but at
higher power there's a bit of hiss and the several percent
distortion is easy to notice.
Since the Dayton Audio DTA- 2 doesn't quite manage
audiophile-quality sound but is still very listenable, I'd
recommend this one for projects where music isn't the
main focus, but you might still want to play music on
occasion and have it be enjoyable. It would also be great
for public address (PA) applications, like haunted house
Halloween projects such as the ones in Photo 23 and
Photo 24. If you're playing spooky sine waves or monster
screams, it doesn't need to be super clear as much as it
needs to be loud.
The flexible mounting options (the on-off/volume
control is able to be mounted separately from the
amplifier itself) mean this could fit into a variety of
enclosures, too — even with both boards, the footprint is
considerably smaller than the other TA2024, so it could
do well where audio was something of an afterthought. It
might also make a good outdoor Bluetooth speaker set
where you wouldn't be able to notice the distortion as
much.
Final Thoughts
Designing your own amp can be a fun project, but in
most cases where you need some volume but don't much
care about the specifics, a module like one of these is the
way to go. Based on my results, any of these modules has
good potential for a variety of different applications. The
PAM8610 would shine in lower powered, non-musical
projects where size is a factor. The model TA2024
amplifier module and the Dayton Audio DTA- 2 digital
version (both based on the Tripath TA2024 class T amp
chip) do a great job and provide more power at lower
distortion.
If you're building a project that's primarily musical, I'd
recommend the model TA2024 on account of its
audiophile-grade performance. For hybrid applications like
sound effects or where you don't quite care about the
sound (like a DIY Bluetooth speaker project), I'd
recommend the Dayton Audio DTA- 2 digital audio
amplifier module.
All of these modules are quite efficient and would be
easily powered by a lead-acid battery. Or, you could add a
switching boost converter if you have a smaller project
that's powered by some LiPo cells or other batteries with a
lower voltage but high power density. If you're like me,
you probably have a few 12V mains power supplies lying
around already. An old computer power supply or even
discarded wall warts could easily power any of these
modules for your next built-in project.
The modules I’ve covered here will also integrate
easily into an existing project, which is part of what makes
them a good bargain. You can unlock your gadget's audio
potential. Happy hacking! NV
PHOTO 23. The Dungeon Keeper
— an animated Halloween prop
which would go well with some
powerful sound effects (Nuts & Volts,
September 2009).
PHOTO 24. The Prop Dropper — a spooky Halloween
project which certainly could use a punch in the audio for
ambient effects (Nuts & Volts, October 2009).
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