upgrade program - why would i need a dealer code?

[RebelMan]

When I did the upgrade from 120 to 220 Pro, I was more than satisfied with the result. Beside a clearer definition of instruments and voices, the 100 Watt extra was what my speakers made shine.
It might be different with other speakers and other acoustic situations in the individual living room.
But when I switched to a new set of speakers the gain in clarity was much greater. The speakers are and will from my point of view always be the weakest part of the audio chain.

Speakers do set the precedent for sound quality followed by the room and then the rest of the ancillaries.  The mistake most people make with power is that they presume having more of it will improve sound quality but this couldn't be further from the truth. 

Provided that the amplifier is performing within its design parameters the first watt will sound no different from the last.  In general, having extra power, 100 watts in this case, only provides for greater sound pressure levels and even then that only amounts to about a 2 to 3 decibel increase. Unless the lesser amp was driven to clip the small increase in power is not going to matter much if any. 

The other mistake people make is assuming they need more power.  Since the vast majority of people do not measure the power demands placed on their system they are simply guessing.  When I have pointed out to others holding similar beliefs just how little power is actually being supplied, usually less than 10 watts (by measure) in most cases, the same people are dumbfounded by the results.  There is no denying that there are exceptions to the rule but they are indeed very rare.

The biggest changes to sound quality, as it relates to amplification, has to do with the architecture NOT power.  The Expert Pro has refined architecture versus the prior Expert series but this refinement is not necessarily an improvement to sound quality.  In fact the consensus among professional reviewers (the same reviewers of both series) has been minor improvements at best and overreaching at worse.  Bear in mind that I also upgraded but not because the 120 was an under powered and/or inferior sounding product, because it absolutely is not.