In simple English, why do we need a custom buffer for Hypex/Purifi eval kits?

[ArthurDK]

Post 2 is simple English.

Most sources can drive an input of say 600ohms and up.
The NC400 has a much higher input impedance and is therefore easy to drive.
The buffer is essentially already built in to the module.
Hypex do not suggest in the product manual that a buffer is required.

If I was to buy an NC400, I would not buy an additional buffer. I would be delighted with the buffer already installed in the module.

Advice freely given.

Almost nothing will drive 600 ohms. You need an input impedance of at least 10K, but better 50 K.

 

[drewmc]

1. The modules with differential input are normally designed so 4v (p-p) input generates maximum output. Single ended (RCA) outputs are designed so 1.8 to 2V (p-p) outputs generate maximum output.
2. What this means in normal English is that driving a differential input amp module with a standard RCA you cannot achieve maximum output.
3. Example: I am using ICE 1000ASP modules and driving them with a miniDSP-2x4HD with unbalanced RCA outs. On some recorded material from early CD's I cannot achieve the volume levels I desire

 

[drewmc]

With modern (non-tube) electronics, impedance is rarely an issue. Differential output and input are superior in all cases when implemented correctly.