Here is almost about everything I can think of that has been changed in my AA5+
I changed to these mainly because the caps Arcam use are not very good
C403, 3300uf 25v Rubycon YK main pcb
C404,C405,C406,C407,C408 1000uf 50v Rubycon YXF main PCB
C205,C206,C241,C242 1000uf 50v Rubycon YXF audio pc
C207,C208,C209,C213 100uf 25v I'm still trying different types here around the +/- 15v variable voltage regs, Andy would probably know what would be best used here, A friend recommended 10uf 25v Oscon's SC and to be honest they sound better than all the others I have tried including Blackgates
You can try any single op-amps for the I/V and filter, I prefer OP27 for both, You can try just about any Analogue Device or Burr Brown for free, just get them to send you some samples for different types, I did, I think I have tried about every op-amp available, be carefull though because some can go unstable
connected a resitor to pins 4 & 6 of Z2,Z102 op-amps to run them in class A
C8,C108 to 120uf 50v Panasonic FC
C13,113 4.7uf Blackgate N type, coupling, try different capacitance here, use whatever you prefer, 1uf Evox SMR sound good aswell
All the other 100uf 25v including C210,C214 22uf 25v for the op-amps have been changed to 100uf 25v Rubycon YXF on the audioboard
Removed Q2,Q102 muting transistors
changed R116,R16 to 100R Holco Resistors and changed R13,R113 to copper wire link
Zero oversampling mod
I got this mod off Audio asylum, cut track joining pin 2 and 4 of Tda1541A, join pin 4 of Tda1541A to pin 9 of SAA7220 filter
The Arcam is also very fussy about what it sits on, If you have a Hi-fi rack with removeable borads, try this, buy a piece of wood the same size as one of the boards and cut a square hole in the middle abit smaller than a sheet of A4 paper, then replace the original shelf/board with the one with the hole in the middle and sit the Arcam on it making sure the feet don't fall through the hole and then have a listen, this mod blew my socks off
it's easy to do an A and B comparison
Use a nice thick mains cable with MK plugs
I'm sure there is alot more that can be improved (any more idea's?) these mods was very cheap and to my ears the Alpha 5+sounds alot better