Troubleshooting
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Thorough testing of the speakers should be carried out both prior to and after plastering
to avoid time consuming repairs or modifications at a later stage. Should you encounter
any problems at either of the test stages the following guide is designed to help determine
possible problem areas.
Advice for testing:
-
When testing always use a basic sound system (amp, source, speakers) to eliminate the possibility
of faults with other, more sophisticated components, such as control systems.
- Test at low and medium volumes and be careful not to exceed the specific speaker model’s
recommended power. Using tone sweeps or music as test material, listen for distortion, buzzing or
rattles at appropriate levels. Using test discs or music, confirm that all channels are in-phase.
- Ideally professional test equipment should be used to record a full frequency response of the
loudspeaker before and after plastering.
No or low sound output:
- Check continuity of all cables.
- Check that all cables and connections are made correctly, are intact and that all channels are
correctly phased (+ to + and - to - from amp to speaker).
- Using an impedance meter, check the nominal impedance of the speaker (APU must not be
connected) both at the terminals and the amp end of the cable. Do these measurements match
each other? (Allowing for the small impedance increase of less than 1 ohm along the wire length)
do they match the stated nominal impedance on the speakers specification label? If the nominal
impedance does not match the product’s stated impedance, a speaker driver may be open
circuited or short circuited. If so, the product may need to be returned to Amina for repair or
replacement.
-If the nominal impedance at the end of the cable is very different to the impedance at the speaker,
check your cables. Cuts or nicks in the cable along its length can dramatically increase impedance
or create a short circuit, dramatically lowering the impedance.
Distortion, buzzing or rattles at modest volumes:
- Try to identify the location of the buzz or rattle. It may be caused by a loose screw or other
mechanical object. Check the wall or ceiling and speaker assembly and ensure screws and fixings
are tight.
- If the rattle persists, remove the speaker from the wall and check your wiring to the product.
Ensure that wires, with the speaker in the final location, are not resting against the speaker or
backbox (if used), causing vibrations.
- With no audio signal applied, lightly push the speaker face in and out at its centre. Listen carefully
for rubbing on the driver, which may sound like scratching. This may indicate the speaker has been
over driven and subsequently damaged. The speaker will need to be sent to Amina for repair or
replacement.
Very low output after speaker passes electrical tests:
- With no audio signal applied, lightly push the panel in and out at its center. Listen carefully for
rubbing voice coils on the driver, which may sound like scratching. This may indicate the speaker
has been over driven and subsequently damaged. The speaker will need to be sent to Amina for
repair.
Distortion at higher volume levels:
- Diffuse source panel loudspeakers of this type have an extremely fast response, articulating
the signal from your audio system very accurately. Take your system back to the bare minimum
(amplifier, source and speakers) to eliminate distortions introduced by other components.
- When using your amplifier at maximum power levels, or if the input of your amplifier is being
overloaded, the signal level may be ‘clipping’. With some conventional speakers this may not be
evident, but with a diffuse source panel speaker you are much more likely to hear the distortion.
Consider adjusting or upgrading your system.
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