eh... i would imagine these products are exactly the same except for the tone controls... hence the same mods and psu 'rolling'
and i'm thinking aiyima will discontinue the old version?
That would be somewhat incorrect... Although we don't know - or shall I say, we have not yet verified, as we have not seen the internals. This new model does show on the product page certain changes...
If it isn't broke... So layout and design won't change too much. But adding tone controls... Those need to be seen and tested. Perhaps they prove to be crap implementations. Adding Bluetooth... I have seen an A07 board on AliExpress that shows that it is the same as the A07 just with that empty space on the board taken up by the Bluetooth module and corresponding components.
5 op-amp sockets on A07 Pro vs 2 on A07
Higher grade caps
Higher grade sagami inductors
Tone controls as you mentioned. But also Bluetooth, just no LDAC.
As far as discontinuing the A07 - They released an A08 then an A08 pro and did not discontinue the other model. Will they though? That remains to be seen. I doubt they will.. They may downgrade the internals a bit... Who knows. I have had 4 A07's, still have 3 and all of the internals are different on each to a certain extent.
Also, as far as other improvements or differences... Based on what could have and should have been implemented correctly on the A07 - The 3.5mm jack and the RCA inputs will most likely not be connected and reversed as they were in the beginning. I actually use the 3.5mm jack as input on my A07 and the RCA out to the subwoofer amplifier. My first unit had vicious cross talk and forced it to be used with 3.5mm as input and RCA out. However left/right channel testing had significant crossing... I could hear the left channel data on the right channel and vice versa. Aiyima claims to have corrected this in the A07. I have not tested it in my currently in-system model though nor have I tested my third unit.
The Pro most likely will be 3.5mm out only and the RCA's strictly input. We shall see.
The original was and is an excellent Amp for the money. Not too many ways to improve upon or change it other than internal components used and better implementation of the rest of it.