Originally Posted by project86
It's been a few months by now - not sure if that qualifies as long term yet, but I'm still very pleased with it. With LCD-2, LCD-3, and all the HiFiMANs, this thing is killer. Alpha Dogs and Thunderpants too.
I can see how people might end up not being impressed though. If you don't use it fully balanced, or don't use it with the right headphones, it becomes just a mediocre amp. I'd stay away from Audio Technica, Ultrasone, most Grados, and a lot of the beyerdynamic models too. Perhaps that makes it a less versatile amp than some would like to own. If you buy something like a Matrix M-Stage or Lake People G109, it will sound good with just about everything. The A28 won't work with every headphone, but when it works it does an extremely good job. So it's all about balancing the system.
i don't know how many people with A28s are actually selling them...but i'm selling mine because, as project86 rightly noted, it doesn't play nicely with low-impedance cans like grados and denons. i have two grados and a denon that i listen to a lot and would like something that is more friendly with all of my headphones, which also include the hd800 and the he-500.
i initially got my A28 with the hopes of mating it with the DA8. i bought one from a head-fier, who, as it turned out, tried to scam me and never shipped it. so there went my balanced source...and i haven't settled on a balanced source since. i have a geek pulse x coming this summer, which should take care of my balanced source need, but having read a number of glowing reviews on the auralic taurus II, i'm settling on that or the ragnarok as my "end game" amp.
so it is not that i didn't like the A28, rather that it didn't mate well with the headphones i have (no wonder that when i first tried it out, and even before project86's review came out, i found that i liked the grados best out of the SE low output, which just turns out to have a lower impedance than the balanced port). furthermore, i have been feeding it with a SE source, which isn't ideal, either. thirdly, i'm moving to what i consider my end game amp, so the A28 simply gets lost in my quest...
if someone is committed to going fully balanced and has the right cadre of headphones, the A28 is a more than capable performer. i still use it daily and i still find it enjoyable, even if it's not "optimal" with the headphones i employ. i hope this is helpful for anyone looking at the A28...i'd be happy to answer any questions, too...