I have the 3 & the 30. The 3 has 4 output transistors per channel, the 30 has 6. The 3 cost more new because of the metalwork. The 30 is more conventional & does have much better anodizing - it won't turn purple/red from heat like the 3s do...
The purists would say the 3 should sound better up to clipping, because it has less output transistors for the music to go through. I honestly can't tell the difference between mine.
The 30 also has speaker binding posts thst are much less cramped (easier to use) than the 3.
Finally, everybody (even non-believers) comments on how unique the 3 ("Borg Cube") looks.
I'd buy whatever comes up at a good price first. You can always buy the other one later......
The purists would say the 3 should sound better up to clipping, because it has less output transistors for the music to go through. I honestly can't tell the difference between mine.
The 30 also has speaker binding posts thst are much less cramped (easier to use) than the 3.
Finally, everybody (even non-believers) comments on how unique the 3 ("Borg Cube") looks.
I'd buy whatever comes up at a good price first. You can always buy the other one later......