Are integrated amps technically better than separates?

@cleeds 

I believe ASR uses external power supplies in their integrated. I have never heard one but it might be an example of form following function. In their opinion, getting the power noise separated must meet their design goals.

Taking away the flexibility factor of separates, is my line of thinking correct?

No. If you want to build an integrated amplifier that has the same performance as separates, you would have to have individual power transformers for each power amp in the box as well as whatever preamp is in the box. In a nutshell you're not likely to see that. Keeping all the ground currents straight is another engineering nightmare that has to be solved too; with individual boxes that's a lot easier!

There is also the issue of speaker cables. If you are running low impedance speakers, the cables become pretty critical and length matters! So you wind up being limited as to how far apart you can place the speakers. I like an expansive soundstage so the speakers need to be far apart; pretty tricky with everything in one box unless you have 16 ohm speakers (where the cables make less difference).


They are a compromise, plain and simple. The only reason this is a topic is because there are good integrated amps and fair separates so there is some crossover. But the best separates are not bettered by an integrated amp. 

On one hand,
in integrated you can make signal path shorter. Especially in low power SET amplifier. You can build 2A3 or 45 amplifier using only 2 stages or 300B with only 3 stages.
In separates you need more stages and more interconnect cables. Each amplification stage, capacitor and cable add distortions and noise. 

On the other hand,
in separated components you can use monoblocks with very short speakers cables, separate power supply transformers and chokes for each channel improves channel separation. A separated power supply for preamp and phono stage make noise level much lower. 

Separates always will be better, technically. Also, separates give you opportunity to optimize amplifier with speakers, without changing signal processing part. In addition to amp flexibility, you can plug active speakers directly into preamp. Moreover, class A and high bias class AB amplifiers running very hot, which is devastating for preamplifier part of integrated, and that will shorten preamp life. 

Each amplification stage, capacitor and cable add distortions and noise.

All those gain stages are in an integrated amp too. Usually though you have a greater chance of lower noise with separates since crosstalk and intermodulations from the other channel won't exist.


To see how profound this is, this morning I was working on an integrated amp, and noticed a very distorted signal at the input of the power amp- on the first stage and throughout that channel. Chased it back to the input, which is all passive components on that amp, and realized that since I was only driving one channel, the unused channel had that distorted input (and output) going on as a result. There is nothing malfunctioning about this amp; but apparently this sort of signal (the result of crosstalk) is adding distortion to the amplifier, which it would not have were the channels merely separated. The amplifier was an older solid state amp made by Trio (Kenwood/Pioneer).