Mod my Denon 3910 or 5910?

[Sleestack]

What you have downstream, so to speak will ceretainly affect any improvement in the mods. The weakest link of couse applies.
As an audio engineer I can tell you the profit margin is great for the Underwood mods.
As far as low level stages being class A, most op amps are class B or AB with very low bias. They can be driven class A with a simple 2 transistor output stage, which will improve the sound of any op. amp, with very little cost.

I'm using components form Classe, Meridian, etc. I'm not worried about weak linms in my system b/c it already sounds great.

As for profit margins... everyone is entitled to make their living.
The price of their mods aren't out of line with the price of other shops and I don't think a total cost of $4500 is unreasonable for a high quality SACD/CD player.
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