I was arranging some things today in preparation for an event this evening and happened to have a little Class-D amp in my office that I normally use in my wood shop. So I decided to try a little A/B testing.
Here is the little 8W / channel Class-D amp.
And here’s what it looks like inside.
This is a fairly simple amp that uses a Sure Audio AA-AB32231 2x8W Class D amplifier module with a Texas Instruments TPA3110 series chip. I installed this amplifier in my shop in April of 2019 to replace an old 1980s boom box that had seen better days.
Since I had this in my office I grabbed a set of identical speakers to the ones I have connected to the 6CY7 V2 Zebrawood and played the same songs through the little class D and the Zebrawood. To say that I was surprised is an understatement! I’ve always considered the Sure class D modules to be very good quality audio amplifiers. And I’ve always been very satisfied with their sound in standalone situations. But this is the first time I’ve ever directly compared them to something else.
I started my comparison with Diana Krall’s rendition of “Narrow Daylight” off of the Girl In The Other Room album. I lined up the tracks and started to switch between the amplifiers letting each play for 20 or 30 seconds then switching. The difference was astounding! I tried track after track, performer after performer, genre after genre. Every time the little 6CY7 Zebrawood was noticeably clearer, fuller, and richer sounding. It was only a subjective test, but what a test it was!
For anyone doubting the veracity of the claims of vacuum tube amplifier superiority, I challenge you to do the same test I did. You may be very surprised.