Class D vs Class A Education

@ Lacee, specifically with respect to 'synergy'. Agree that as you state 'To me, the ultimate synergy is when the whole becomes one.' which is a nice summation of complete synergy, I suppose. If I infer correctly that that statement is referring to the end listening experience, then it would have to include the room as well.

Certain simple, fundamental starting blocks for synergy: ensuring that output/input impedances match spec-wise. That your amp and speakers are well matched (ie amp not underpowered, or perhaps a low-powered amp designed for crossoverless high efficiency speakers). Maybe buying all the same brand of components. Speaking to the manufacturer of the various components in your system and garnering their opinions and others on equipment matching (hence the bajillions of 'what type of X goes best with Y?' posts).

Beyond the obvious, there are simply times when components work better with some than others. Cabling, etc is also true of this. My synergy comment was meant only as a baseline. Beyond that, IMO Class D vs A comes down to a personal thing, and in the right setup can sound fantastic.

I hope nobody out there writes off Class D as a whole based on others' blanket statements without hearing at least a few different class D amps in their own listening room.

Perhaps my interpretation of synergy is a tad harsh, but I also dislike the term neutral.

What is neutral? Todays neutral amp/cable/? is tomorrows coloured one.
Really up to one's experience and personal opinion.
At best you can only say one cable is more neutral than the other, but which cable- ie is the benchmark of neutrality to which all other cables or components can be compared to?
I hope you can try to understand what I am implying.

I think there is nothing wrong with assembling a system that works together well and plays the tunes, but even a smorgasbord type should do that.Careful matching is the best way to go, but what are we really trying to do when we strive for synergy?

We are trying to cover up one deficiency with another, and to me that's just like using different lenses in photography - distort reality but create a pleasing photo.
Much as in photo shop in digital photog.
Reality is not the issue, but "synergy" is.

Synergy to me in the worst case scenario is when you take a bass shy component , match it to fat sounding cables and run everything thru a tube buffer to smooth out all the rough spots.
In doing so, how much reality and truthfulness to the original have you destroyed?
Is a "musical" sounding system, tuned to make all recordings sound pleasant, whether they are good or bad,the pot of gold we are supposed to be chasing after?
I want my system to be able to differentiate between recordings.
The good recordings will sound great, lesser well recorded will sound as they should sound.That's reality, and if that sucks well you know the rest of the saying.

Why blend everything together in a sonic soup called synergy?

Until we can someday have a set of standards that we can make comparisons to, all we have at our disposal are the old guard terminology.

Well-said. Some systems that are true to the source, others are euphonic, and others are neither.

>> Can anyone some it up in a nut shell if possible what
>> the difference in design and output are of class D vs
>> class A power?
>>
>> Thank You!

I believe, from reading the above text, that you asked for an education in class-D vs. class-A design. I do not think that anyone provided that so far. Lacee has vomited a lot of text & bored us w/ his opinions but there is hardly any shred of technical discussion here per what the author of this thread asked for.

I was curious myself about this topic & rather disappointed that not a single member initiated a technical discussion as requested by the author. I did some research & found a very good explanation (NOT IN A NUTSHELL, mind you!) on class-D audio power amps:

http://sound.westhost.com/articles/pwm.htm

class-A amplifiers are more traditional in comparison & are also the most INefficient in their overall power comsumption because the theoretical max. eff. of a class-A power amp is 25% i.e. it burns 4W in order to deliver 1W to the load. Class-A power are, usually, designed with the output power transistors biased at maximum output current bias (hence the heat) whether there is a (music) signal or not. Hence, class-A power amps need to pay a lot of attention to transformer selection & size of the heatsink (to dissipate all that heat from the full-biased output transistors). It is not uncommon for a 100W/ch pure class-A power amp to have its heatsinks measure 54 degrees Celcius. In comparison, the class-D power amp heatsink is as cool as a cucumber. For a class-A power amp, since its current consumption is so high, the transformer size has to be quite large - according to Nelson Pass, 2-3X the calculated value should be chosen from a VA standpoint (if my memory serves me correctly from one of many enlightening white papers). In class-A the designer also has to pay a lot of attention to output distortion by ensuring that the output transistors always remain in the SOA (safe area of operation) otherwise, you'll be SOL ;-) and the amplifier output signal will clip & destroy the loudspeaker either immediately or over (short) time. Needless to say, with the large heatsink & large xformer, class-A amplifiers are very heavy items while the equivalent class-D power amp is much smaller & lighter.

Sonically, class-A & class-D power amps are very different with the class-A sonics being much more appealing TO ME personally but to each his/her own. There is no right or wrong sound - only sound that pleases or does not please YOU, the listener.

I am very confused lol. Guess what I will need to do is demo and a/b as much as I can. Because as with any equipment its personal taste and experience will define what I wanna hear. I do appreciate everyones comments, feedback and humor. We should have an audiogon meet and greet somewhere :)