Class D is just Dandy!


I thought it was time we had a pro- Class D thread. There's plenty of threads about comparisons, or detractors of Class D.

That's fine, you don't have to like Class D amps, and if you don't please go participate on one of those threads.

For those of us who are very happy and excited about having musical, capable amps that we can afford to keep on 24/7 and don't require large spaces to put them in, this thread is for you.

Please share your experiences with class D amps!
erik_squires
Erik,

There is no misunderstanding at all and I apologize for my writing not being very clear at times. I understood completely what you asked, and that is you want to see is the real frequency response plot of the amp while driving such a load and also to determine what the 3 dB points are for both frequency extremes. Again, the answer is NO. I have not done the measurement. Because of the output filter of the icepower, and most of class D amp, I would speculate that there will be some high frequency attenuation at very high frequency due to the impedance raise of the inductor.

What I meant by lowest output impedance of the amp, especially completely flat up to the extreme treble region, is not necessarily always good is that it depend on the system. IMHO and IME, extreme low output impedance amp does not sound very good when mating to a highly damped loudspeakers. This is the very reason why tubeohiles really object to solid state amps, especially those with lots and lots negative feedback, to lower output impedance and distortion. The end result of such mating results in a sterile and one note bass and everything is too tightly control. Therefore, there is not much left in terms of air around instruments, much smaller soundstage, Closed-in midrange,
harsh and sterile treble etc... I am speaking strictly in terms of conventional discrete transistor design. I have designed, built, test, tried this and tried that for as long as I can remember. I agree with you about experience. There is no substitute for that.  Also, Absolutely! Apogee did put Krell on the map for sure.

Henry


Henry,
I would be more inclined to measure the in room response of your speakers and see what you get.

Kenny.
John,

It is very rare to find a Scintillas owner.  Are you located in Texas? 

Henry
Kenny,

Unfortunately, I am not very well equipped with instruments to perform such tasks.

Henry
Erik,

Just to add a bit about the Scintillas. Sure, they are closer to a short over the entire audio frequency spectrum than any other speakers to date. It is not that hard to design a conventional linear class A amp to deal with that which I have done. But what compounding to the low impedance problem is their efficiency, and if I remember correctly, Stereophile’s measurement came up with was in the mid 70 dB or so. And Here is where it is an equally challenging task to deliver substantial power into such low impedance and inefficient load.

Henry