It is obvious that Class D is a devisive topic here in the cloisters of the initiated disciples of The Church of True HIFI, where the ancient mysteries of valves and Class A remain holy relics and new technologies are deemed heathen and unworthy. I must confess a certain degree of schizophrenia myself; the Gear-geek side of me is overjoyed with these new toys and is loving every second, the inner-Audiophile is behaving in a slightly snooty way and is not easily convinced of the musicality of these Sci-Fi-styled creations.
Lets have a look at the object in question, the Sabaj A10a 2022. Firstly, what you get is a very cheap (160 quid at Amazon) little stereo amp with single input and a minimalist front featuring a huge on/off switch and a chunky volume knob. Inside there is a new-generation Class D processing chip from Germany called the Infineon MA5332M. However things get more complicated on the back :
The left-hand side on the picture shows 4 little switches and a small silver knob. These select 1) Bluetooth or Line input, 2) straight signal or roll-off, 3) stereo/bridged mode 4) RCA or XLR input. Then you see that this is a versatile unit designed with A/V applications in mind; for instance you can hook up one of these in stereo mode to a TV and a second A10a in bridged mode driving a passive subwoofer (that is where the silver roll-off knob comes in). For surround installations you can implement one A10a per channel and each can be adjusted for balance with its own volume pot. Handy.
Due to its small footprint and low price this is also an ideal stereo starter amp or one for use in a second system where you just need background or party (it goes loud!) sounds. But, then the burning question, does it sound any good?
Beginning with a single amp in stereo mode, I was impressed by the muscle and clarity of the A10a, Up-front, sharp detail, tactile & punchy bass. Fun, certainly, Hifi? Well, yes, in a way, Audiophile? No, lacking too much in depth and subtlety. The stereo field is certainly nicely-defined with a wide soundstage and oodles of detail, it improved as well when I swapped in the DacMagic DAC as a source, the softer, rounder sound balancing well with the forward character of the amp.
Then, amp 2, bridge mode.
For only 320 pounds you get a pair of hefty little monoblocks, Sabaj make another version called the A20a which takes the same chassis but increases the output to a higher level. Oomph. So, we have here a powerhouse amplifier setup, nice that both units have a volume pot as that makes balance adjustment possible, something I didn't have up to now. Those of us who use digital, chip-based audio equipment know that warming-up and running-in make a significant difference to the eventual sound quality and I have had the second amp for less than 24 hours. Leaving the whole setup on overnight, everything was nicely warmed-through (despite -7C outside) this morning and I have just had a short but critical listen.
Tangerine Dream sound amazing through these! No doubt about it. Every bleep, bloop and phase-effect is presented with astonishing sharpness. The wide soundstage is more definitively-defined than I can ever remember with other amplifiers. The sound isn't excessively bright but it is on the borderline sometimes. Complex passages just lack a tiny bit of control and there is an overall 'artificial' sheen to the character that makes the music come across as a touch 'stiff'. This isn't a problem with synth/EM at all, but how about real people playing real instruments? Not bad, actually, I gave Joni Mitchell's wonderful live 'Miles of Aisles' a spin and that worked rather well, being a bass-player I always try to follow bass-lines and the Sabaj amps present those on a plate. Easy to feel exactly what the bassist is doing in this great live-band. And Joni singing, playing piano and guitar, everything is vivid, technicolour sound. No holding back on detail - I have never been able to pick out some audience comments before now, and I could clearly make out what folks were shouting to Joni. As I said, this Hifi-geek is dead chuffed.
Subtlety, a sense of 3D depth and relaxed involvement. These are qualities that the inner-Audiophile (the snob!) still misses and has his reservations about. The question is, will a period of burn-in bring out more of those qualities in the Sabaj A10a? It can take weeks of use for audio gear to really come on song and I have little experience of Class D and cannot say for sure - but will see and hear this for myself.
For the moment, however, I am really, truly impressed.
