Sugden Amps

The benefit of Klipsch Heritage speakers, aside from nice sound, obviously, is the loudspeaker efficiency and the opportunity to experiment with confidence when it comes to lower power-rated amplification. If you aren’t going with a pure class-A amp (something about that "all-day, everyday" desire and the reality of significant heat generation from pure class-A makes me wonder if that is a good thing long-term), there are good hybrid options in Class A/ Class D. (NuPrime’s IDA-8 is Class A-Class D and has a low noise floor. Very compact. 100W.) The JBL SA750 has A/AB ("Class G") topology with a streamer, DAC and remote, 120W.

That's precisely why I bought some Klipsch Forte 4s (to experiment). I'm having difficulty deciding between class-A SS amp and tubes. Heat isn't a problem as I would use (whichever) only in the winter. I've owned tubes but never had a first-class preamp (like my current BAT VK-33SE) to show off their potential. On the other hand, I've never owned a class-A SS amp but my BAT VK-255SE is so good (IMO) that a class-A SS may be redundant. Fortunately, there is no hurry so will keep deliberating until I receive some divine guidance/inspiration.

At the risk of offending those gentle readers who do not prefer direct-to-consumer products, you might also consider the Schiit preamps and amps for your Klipsch Heritage speakers. The Freya+ (ss/buffer/tube-selectable and rollable) and the new Kara (ss) are balanced-output and the Schiit Gjallarhorn and Aegir "continuity" amps can be run in monoblock or stereo (more power with mono, obvs, and with the Aegir, balanced input is only with mono). U.S.-made, as with all Schiit products, if that is important, and power output would be adequate: 80WPC with Aegirs and 30 WPC with the Gjallarhorn, either greater than the Sugden, FWIW, and less expensive as well, all-in.

@chenry Any opinion about sound quality regarding the Schiit gear? The Sugden is supposed to be musical as all get-out. Thanks. 

I have the Schiit Freya+ preamp, using it with an active speaker pair at the moment, and it is an excellent preamp. In tube mode, (with 6SN7 x 4 ) it gives 12dB gain and gets fairly warm, less so if using the LISST solid-state "tubes"  I have not tried it yet with Schiit's amps, mono or stereo. (I'm tempted, I have a pair of ELAC speakers that might benefit.)

I was just looking at Youtube reviews of the Sugden A21SE and the Musical Fidelity A1 (newest version). It was interesting to see the Musical Fidelity had twice as many output filter capacitors in its circuit (all of them 10KuF in both), although the Sugden seemed a little more robust overall. I'm not sure what to make of that.