but getting up into the range
where I might not consider it
audiophile quality.
The sound itself was
clean and neutral through
the middle of the range (if a
bit thin sounding), and not
unpleasant or fatiguing at all.
At the high end of the power
output, though, a noticeable
hiss came up from the
background and the
distortion became quite
apparent. The audio was still
very intelligible, however.
One thing about this
module is that it would
definitely benefit from a
heatsink. After about five minutes playing at the full rated
volume, a whisp of smoke arose from the QA sticker
which was on the top of the chip. The thermal cut-off
killed the output. I think in a real world application, it's
unlikely to be run deep into the red the entire time, so I
don't see this as a huge problem.
Smoke coming from electronics is never a fun sight,
but there was no actual damage. It fired right back up
after cooling off, and its performance was unchanged.
The chip is large enough that it would be easy to fit
with a heatsink for better thermal performance, and that
would almost certainly solve the problem. If you're
mounting this in a small enclosure without much
ventilation, it'd be a very good idea to include one.
I'd recommend this module for any application that
might actually play back music based on its good
performance, or where picking out fine details of the
sound over speakers might be important; for example, in
something like the Big Ear project referred to in Photo 19.
A Flexible, Full Stack Solution
The second of the TA2024-based amplifier modules is
the Dayton Audio DTA- 2 digital audio version. This one
goes the opposite direction of the bare board: It has a
power connector (although there are solder pads for a
hard-wired power supply); a 1.8" stereo mini jack for the
input signal; and a volume knob with an integrated power
switch on a second small printed circuit board (PCB)
connected by a flexible ribbon cable (Photo 20).
There's also an LED power indicator which I didn't
assemble for these tests. The speaker leads need to be
soldered to the board which is a little annoying, but not
PHOTO 20. The DTA- 2 digital audio amplifier module
with all of its pieces.
PHOTO 19. The Big Ear
distant listening device to
pick up sounds from far
away (Nuts & Volts,
December 2008).
PHOTO 21. The DTA- 2 under test.
PHOTO 22. Dayton Audio DTA- 2 measured into four
and eight ohm loads from 0.25W through maximum
power output.
52 March 2015