Top positive review
Fabulous, true quality audio - with honest specs
Reviewed in the United States on February 26, 2020
I am *very* pleased with the KD-W02. I looked for an AMP that had the right set of features: Enough clean power for a average sized den, a sub-out for a powered sub, and a nice selection of ‘front-end’ inputs. There are a number of possible amps to look at, I tried a few, but they are all poorly labeled for the true specifications that matter. Lots of amps quote the power as ‘peak’ power, many using the same boardset from China that is ‘100W’. Well let me do the math for you on these rather expensive, poor products – I tested one and I am an Electrical Enginner: 100W peak total is 50W peak per channel, which in the world of real audio the only measure of power is RMS. RMS is .707 of peak (for a sine wave signal that is representative of audio). So these “100W” amps quickly become 35W RMS per channel. But don’t stop there. They then fool you by specing it to a 4ohm load. Most quality home speakers are 8ohms, so now you need to cut that figure in half for 8 ohms! – Now you have a 17W RMS per channel amp. And then you need to look at the THD (total harmonic distortion). Many of these amps are 0.5% THD, which on the surface doesn’t seem too bad, but the KD-W02 is a quality design that has 0.01% THD – 50 times LESS. You want power to be clean and quality audio amps have that level of THD, not ½ a percent! I bought one and while I no longer own an oscilloscope to really test it, my guess is it was more 15-20WRMS.
I enjoy my KD every evening – drive the KD from my Alexa /Bluetooth (it requires a nice Bluetooth dongle to get the best signal – never could get just Alexa to pair, but that is an Alexa problem as it is so bad about pairing to most speakers) and also have a Plex Media Server on a Raspberry Pi 3B+ with all my music that feeds over wifi to another Plex client (called Rasplex) on another Pi (W) that has a mini HDMI dongle that splits out a sub-jack audio signal I feed into the sub-audio IN to this great amp. I have a Polk Audio 10” powered sub, and then two small 2-way Mirage speakers that get the L/R. So having the AMP act as a band stop filter is an added bonus to protect those channels.
It’s an Excellent product for modern digital home audio! And like I said, true 40w RMS into an 8 ohm load, super clean THD. Plenty of power.