PS Audio Stellar M700 Instructions For Use Manual - page 9
4826 Sterling Drive, Boulder, CO 80301
Troubleshooting
PH: 720.406.8946 support@psaudio.com www.psaudio.com
15-076-01-1
Rev A
Troubleshooting
©2017 PS Audio Inc. All rights reserved.
®
Owner’s Reference
Stellar S300 and M700 Amplifiers
Check to make sure power is going into the Stellar and it is connected to a live source. Make sure the
rear panel master power switch is in the on position. Push the front panel logo light. Check the speaker
cable connections to the speakers.
If there is hum coming from your loudspeakers it may be coming from your preamplifier, or it may come
from an interaction between components in your system and Stellar. This type of interaction is known
as a ground loop.
The first step to determine where the hum is coming from is to place the Stellar in Output Disable
Mode and remove the input connection from the preamplifier. Turn the amp back on and see if there
is hum. Chances are good there will not be. If the hum is a low frequency soft sound, see if its level
goes up and down with the preamp volume control. If it does, the problem is in the preamplifier. If not,
it may be in your connecting cables. Try a different set. If the hum is a sharper buzz it is most likely a
ground loop.
The easiest way to figure out where ground loop problems lie is by the process of elimination. You
need to determine where the hum or buzz is coming from within your system. If the hum/buzz goes
away when you remove the inputs to the power amp, your next step will be to reconnect the amp and
move further down the chain. It is important to do this in the correct order and take the time to perform
the test in a methodical step-by-step manner.
If you have a preamp, or processor that is feeding the power amp, your next step would be to
disconnect all inputs to the preamplifier or processor. Once these are disconnected, and the preamp
or processor is connected only to the power amplifier, turn the system on and again, listen for hum.
Should the hum now appear, it is a problem with your preamp or processor or their interaction with the
power amp. Before returning the preamp or processor to the manufacturer, try a cheater plug to break
a ground loop. Cheater plugs are simple devices that convert a three prong AC plug into a two prong
AC plug and in the act of converting three prongs to two prongs they disconnect the ground from the
wall socket. Try one of these on the preamp, or the power amp, or both.
If you determine that there is still no hum present when the preamp, processor or receiver is connected
with no inputs, then selectively begin plugging in your various inputs one at a time. After each
connection, check for hum until you discover the humming culprit. Use the same method described
above to remove the ground on the offending piece of kit.
Hum and Ground
Loops
6
The Stellar Amplifier is designed to protect itself if it detects a dangerous signal surge or transient
that could damage the circuit. In these instances the Stellar goes into Fault Protect Mode. If you see
the blue logo button flashing quickly and the Stellar turns itself off, then it has entered this mode.
This can happen if the Stellar is heavily overdriven.
If this occurs remove power from the Stellar and disconnect all inputs and outputs. Then, power the
Stellar back on and verify that it powers on normally. If this is the case then power off the Stellar and
re-connect the speakers and sources. Try playing music back at a low level at first.
If after removing all connected equipment the Stellar continues to enter Fault Protect Mode , please
contact PS Audio.
Fault Protect
Mode
No Sound Comes
From the Stellar