Amps that don’t impersonate space heaters.


There have been some epically hot periods in metropolitan Chicago this summer. I have had a long running affair with a pair of Avantgarde Uno s2’s and don’t really require a great deal of power. I have two dissimilar but equally compelling amps (a Pass 30.5 and a BAT vk-56) both prodigeous producers of heat creating a sauna like environment in my library/listening room the HVAC system not withstanding. What, if anything, have you boys and girls found that might replicate the qualities of my beloved amps minus the potential for 3rd degree burns and heat prostration?
Cheers and good fortune to you all. 

williamjohnston

Slam” is a very interesting attribute. What does it mean? Do you hear this “slam” when listening to live music? Is this “slam” an accurate representation of what’s on a recording or is it emphasis of particular frequency range that one component features over another? In most cases, “slam” is not real. Accurate reproduction/presentation is what I value in my system. This includes dynamics, tone, focus, layering, separation, soundstage. Coda is balanced pretty well in that regard. Imo

“Slam” is perhaps not the best descriptor for what I was trying to convey. To be more concise, my Yamaha seems to provide better woofer control and authority than the Coda 8 in the lowest two octaves, even with speakers that have a -3dB point of ≈35Hz. It wasn't notable until I swapped the Yamaha back into the system. Otherwise the No.8 did sound quite balanced, but then so does the Yamaha. So it doesn’t seem to be a linearity effect, but more to do with outright extension and damping factor. The Coda has more power on paper but the Yamaha 2100 sounds more powerful in practice—more “effortless.” That’s the best way I can describe the difference. 

 

My Parasound A21 sounds more powerful on the whole than either aforementioned amp, but it still doesn’t seem to plumb the lowest octave quite as deeply as the Yamaha. But among the dozens of amps I’ve owned, the Yamaha digs the deepest for some reason. That’s not to say the Coda is a slouch in that regard, it is certainly better than the majority of Class D amps, without question. 
 


 

 

@helomech Coda CSib appeared to have less bass than my Pass monoblocks initially in my system. As I spent more time with it, I realized the bass Coda produces is accurate, fast and tuneful. There’s plenty of it too. It will not shake walls which usually comes at the expense of quality of the bass and you end up with a one note huge bass output that lacks definition, texture and speed. Highly dependent on speakers, associated equipment and personal preferences though…

@audphile1

I know the sort of thing you’re referencing regarding bass quality vs quantity, but that’s not what was going on with the No.8 vs the Yamaha. With the Yamaha, the bass sounded as though it dug a whole half octave deeper. I asked Doug at Coda if having the V1 boosted to V2 or V3 level would bridge that gap but he didn’t think it would.

One recurring theme I encountered in researching this phenomenon is that bass roll-off is a common trait among amps employing zero global feedback. I can’t say for sure what the culprit is but I owned about 5 different pair of speakers at the time and the same difference was audible with all of them. With my Magnepans specifically, I was not impressed with the Coda despite its alleged current output. Putting the A21 to the Magnepans following the Coda was a revelation.

I do still like the Coda amp on the whole. It was very quiet at least, much quieter than most amps.

 

One recurring theme I encountered in researching this phenomenon is that bass roll-off is a common trait among amps employing zero global feedback.

@helomech I've seen zero feedback amps that go full power to 1Hz and don't seem to lack any bass at all. IOW its not a common trait.