What could I expect to hear from a Class A amp?

Class D amp have miles to go, to even be remotley considered in the realm of pure Class A amps. Even with the attendent penalities of Class A operation of high cost, high heat, heavy chassis, the need to be powered 24/7, additional usage of power to your monthly bill. Even with that all against Class A amplifiers, once you hear and become accustom to the signature of Class A, there is no turning back.

I myself at the moment using a Class D amp in the PS Audio HCA 2 which I would never compare to a properly made Class A amp. While close, it is no cigar. No doubt that Class D will evolve in years to come, but not just yet. I have listen to the Rowland, Channel Island, Nu Force as well as the PS Audio I have here. The only Class D amp that comes close enough to warrant a close examination is the Rowland.

The rest are nothing more or less than contenders at this point in time.

Detail without fatigue.
Smoothness without the mush.

Could somebody please comment about the 24/7 operation needed for Class A. Typically I heard that you want to warm it up for 30-60 minutes. Yet it seems to take about 4-5 hours before my ears could not distinguish a difference.

I definitely agree about the non-fatigue factor since your brain does not have to fill in. Before getting the XA60.5, it's like a love-hate thing I have with the stereo. I must listen to it because I love music. But about half an hour later, I got tired, somewhat disappointed, and turn on the TV instead.

Ferrari, that would be calling me a fibber. Like I wrote, I used other conventional amps, including Pass Labs fair. Nothing ever came close, including the latest class A ware that approaches the fierce speed of resolution to the faintest nuances offered by my amps and preamp by the same maker.

I hope you don't mind me offering just few pointers when auditioning class D amps. First of all, don't be sure your system is conducive to class D amps. Secondly, there is a quality hierarchy applicable to class D amps as you found out.

On the first point, I have had the same monos and preamp for years of listening. During that time, the resultant sound moved through a series of personalities. At one time, it was airy and whimsical. Another time it sounded warm but focused.

After eschewing commercial speaker cables, and employed the short ribbons I use now, the sound took a revolutionized step. I upgraded my non oversampling DAC which I sent to Henry Ho of H2O to work his genius on. The stage stretched fore and aft, bass grew in heft and musicality, highs perfection, mids as natural as it gets. The last amazing surge in fidelity occurred when

I could go on and on. If I thought any of the class A amps could do me more, I would be happy to buy them. The knowledge Henry makes class D amps and class A preamps to be as squeaky clean as can be, I knew there was a way to harness the best possibilities.

I talked with the manager at Sugden.
His opinion is the amp needs 10 minutes warm up time.