I tested A-414 last night. Wow, I was pleasantly surprised. This was my first experience with Class D amp and I was quite amazed with what that little guy does. Little just by physical size. I completed one channel only, and compared it to my Hafler 9505.
A 414 is 400W @ 4 ohms, if fed with 80V. I had PS that was giving me around 65V. Even with that it was closing on the Hafler with its punch. Quite amazing bass! I need to finish second channel and to give it a full listening test in order for me to report fully, but I will tell you, for the price and what I heard last night, wow.
A few notes for users that have not been very clear from the data available on the site, so I got clarification, and would like to share it with you.
Regarding connectors and voltages:
Connectors J1 and J4 are identical, and only one is used. The other one is used ether to bypass signal to second amp or to add more capacitance to the amplifier (clever idea) So if you will be using J1 to connect your power supply:
First four pins - only two are used. Pin 1 and Pin 3 or Pin2 and Pin 3 or 4. Since we do not need dual power supply for this amp, any voltage between 30 and 80V will do it. Positive supply is connected to ether Pin 1 or Pin 2, or both if you would like to increase the wire diameter. Pin 3 and Pin 4 are ground for that supply.
Next Pins 5,7,8 and 9 are used.
Pin 5 is +15 V
Pin 6 is not used (-15V is there if there is a need to pass through voltage for the preamap)
Pin 7 + 5V
Pin 8 - 5V
Pin 9 A Ground for 5 V and 15 V supply
Current demand on the power supply for 15 and 5 voltages follows:
Voltage Current
+15v 53mA
-15v 0 ma
+5v 67mA
-5v 49mA
One important fact to mention is the info I received from PowerPhysics:
"The potential of the -5V must be greater than or equal to the +5V during the turn off sequence. (|-5v| >= +5v) This issue occurred once with a preamp that loaded the -5v supply from the amplifier with a number of LEDs. The -5 current draw of the amplifier preamplifier combination was greater than that of the +5V and the A-414 did not like this condition. With just the A-414 attached to a power supply there is normally no problem as I5v > -I5v so V-5v > V+5v as the voltages decay during turn off.
This note has also been added to the A-414 specification."
Connector J3
Pin 1 and Pin 3 are used for positive and negative output to the speaker. This is bridged amp and ground Pin 2 is not used. That pin is used if you would like to do shielding of the speaker wire and speaker itself only.
Connector J2
There you only need to use Audio input pins. Those are Pin 1, 2 and 3. Connector with installed ribbon cable is supplied. The rest of pins are used for various monitoring functions, that are great to have, but you do not need them immediately to test the amp. For their usage read the supplied documentation.
I hope this help lucky winners.
Best
AR2 - Vladimir