6/17/2017
XKITZ XAMP-M2
9
Power Supply
The XAMP-M2 requires only a single positive DC voltage from 22V up to about 50V. The LM4766 will only
operate properly in this voltage range. The higher the voltage, the more audio power it will produce. Higher
supply voltage will also put out cleaner audio, even if you’re not running it loud, but it will consume more
power.
On the XAMP-M2 there is no real advantage to using a supply voltage greater than 34V, as this won’t lead to
any higher power output, and will only cause more unnecessary heat for you heat sink to dissipate.
Batteries are a good choice for powering the XAMP-M2, they will provide very clean DC voltage. A good selection
would be two small 12V lead acid batteries in series. This has the advantage of being rechargeable, and they’re
reasonably priced.
If you plan to run the amplifier from AC mains voltage, either 110 or 220VAC, consider our Audio Grade 200W
DC power supply: the XAPS-200W. It takes in AC from a power transformer and creates very clean, well
regulated DC voltage for your amplifier.
Troubleshooting
If you’re having trouble with your device, check Table 5 below for possible cause and solution.
Table 5.
Troubleshooting Guide
Problem
Possible Cause
Solution
Power supply not
working, no input
signal
•
Verify DC voltage input is applied and connected OK
•
Check line level signal wiring
No activity - circuit
doesn't seem to do
anything
Power supply
voltage out of the
range of 22V-50V
•
The LM4766 amplifier chip will not operate outside of this
voltage range
Sounds bad, muffled
Woofer/Tweeter
swapped
If the woofer and tweeter driver wires get swapped, it will sound
very bad, check your wiring.
60Hz audible hum
Grounding
problems, noise
on the DC supply
•
Make sure all you’re audio source and amplifier and any
other components are solidly grounded to earth ground
•
Try driving the amp with a 9V battery, if the hum goes
away then there’s noise on your DC power supply.
•
Change line-in configuration: balanced or unbalanced