Just the perspective of someone who struggles with the design trade-offs, both technical and the big one **COST**.
The unsaid part here is that everything is a compromise of what we want to do, against what we can afford to do - in design, mechanical, parts quality and quantity, etc. I think the original poster, who was assailed for having a "technical" perspective was simply aware of some of these trade offs that in the end, limit sound-for-dollar. I mostly agree with them. No matter either way.
An integrated amp reduces spend on several very costly parts that don’t contribute directly (yes indirectly) to sound quality - chiefly among them one chassis vs two. The big ticket items in almost anything are the chassis, heat sinks, transformer, and trim. Electronics are fairly modest. Heck, the packaging (cardboard box, etc.) often costs more than the circuitry itself. And you cut that in half too.
So the cost can come down faster than the quality.
There are issues with integrated amps, some noted above, but what has not been noted is that with some effort and money they can be overcome. Chief among them is the power supply compromise. I’ve done a couple of integrated designs, one as a contract, and i simply did not make that compromise - easy as that. Spend the money, build multiple idealized supplies. QED.
So the theme is valid - reduce cost, hopefully with a less-than-proportional reduction in sound quality. What will be lost?:
- -- flexibility to have different power levels or to change them
- -- chassis isolation of the low level from high level circuitry (a big deal IMNSHO)
- -- flexibility to locate amps near speakers and pre-amps near the listener (another biggie to me)
- -- stuff i wont go into.
At the end of the day most people would be well served by a truly great 30W integrated. More money could be then spent on DACs/timing/speakers/vinyl reproducers where the differences are larger and the laws of physics sometimes conspire to make bigger better.
In fact I just slapped my own circuitry in a vintage integrated chassis from [fill-in high quality 1970’s Japanese manufacturer here] for my bedroom. And yep, i built three power supplies and somehow wedged them in :-)