Submariner1
Senior Member
- Joined
- Sep 3, 2016
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- Location
- Windsor Berkshire
- Your Mercedes
- CL500 2009 5.5
Q1. Can I “safely” test the wiring integrity and speaker voice-coils on one channel by using a Fluke auto-ranging multimeter, attached to the Amplifier’s disconnected speaker terminal block ? I.e. test in situ.
Reason for testing
Basically to rule out any shorting on the channel’s wiring and or rule out any broken/faulty voice coils, which might account for the intermittent loss of sound on all channels except This one.
My Logic
Whenever the sound distorts, its only on the left door’s Mid-Range and Tweeter speakers. The wiring diagram shows me this tweeter is joined in parallel to the mid range Speaker, the Tweeter has a capacitor to filter and block the low frequencies, I therefore assume the midrange may? (But I can’t see without taking off the door card) have a coil and a capacitor to isolate the mid range.
It seemed sensible, while the Amp is away being tested, and hopefully repaired at BBA, to test from the disconnected speaker terminal block. See below.
Reasons:
- enables me to verify the Amplifier has been repaired properly
- if there was a wiring / speaker problem, it would be stupid to re-connect a repaired amplifier ... only for potentially faulty wiring or a faulty voicecoil to blow the amplifier’s output stages again.
... the circle could go on forever.
- the shortest route to a full cure.
- it may prevent faulty wiring damaging any speakers that have survived todate.
The shortcomings of my logic
Ideally one should have an Audio AC Impedance Meter to test the impedance of a speaker. But a DC Resistance meter will give me a close enough reading, at least to know they arent going OL or are wildly off, or shorting to ground or each other.
Likewise, I think technically I should:
1. Disconnect both speakers and test the wiring on its own Amp to Mid range.
- and then Disconnect the connector ( mid-range speaker to tweeter ) and check the Tweeter’s extended wiring.
2. Then, Test each speaker individually excluding coils and caps , and later test each coil and cap.
The difficulty is I dont want to take the door card off , and that is essential to get to the midrange speaker and the Tweeter connector.
I dont know if one tests the whole Channel by touching the Amplifier speaker wiring terminals inside the connector block, if one could damage the Capacitors in HK’s basic crossovers. Any views on this?
My other idea was to also test the resistance of the Right Midrange- Tweeter channel.
I.e. if they are the same, then I can assume all is well with the left door’s wiring and speakers.
The question is, is it safe for the speakers voicecoils and associated coils and especially the capacitors to simply test by connecting the Multimeter to the + and - at the Amplifier connector block?
Could I damage anything within the left midrange speaker channel?
Reason for testing
Basically to rule out any shorting on the channel’s wiring and or rule out any broken/faulty voice coils, which might account for the intermittent loss of sound on all channels except This one.
My Logic
Whenever the sound distorts, its only on the left door’s Mid-Range and Tweeter speakers. The wiring diagram shows me this tweeter is joined in parallel to the mid range Speaker, the Tweeter has a capacitor to filter and block the low frequencies, I therefore assume the midrange may? (But I can’t see without taking off the door card) have a coil and a capacitor to isolate the mid range.
It seemed sensible, while the Amp is away being tested, and hopefully repaired at BBA, to test from the disconnected speaker terminal block. See below.
Reasons:
- enables me to verify the Amplifier has been repaired properly
- if there was a wiring / speaker problem, it would be stupid to re-connect a repaired amplifier ... only for potentially faulty wiring or a faulty voicecoil to blow the amplifier’s output stages again.
... the circle could go on forever.
- the shortest route to a full cure.
- it may prevent faulty wiring damaging any speakers that have survived todate.
The shortcomings of my logic
Ideally one should have an Audio AC Impedance Meter to test the impedance of a speaker. But a DC Resistance meter will give me a close enough reading, at least to know they arent going OL or are wildly off, or shorting to ground or each other.
Likewise, I think technically I should:
1. Disconnect both speakers and test the wiring on its own Amp to Mid range.
- and then Disconnect the connector ( mid-range speaker to tweeter ) and check the Tweeter’s extended wiring.
2. Then, Test each speaker individually excluding coils and caps , and later test each coil and cap.
The difficulty is I dont want to take the door card off , and that is essential to get to the midrange speaker and the Tweeter connector.
I dont know if one tests the whole Channel by touching the Amplifier speaker wiring terminals inside the connector block, if one could damage the Capacitors in HK’s basic crossovers. Any views on this?
My other idea was to also test the resistance of the Right Midrange- Tweeter channel.
I.e. if they are the same, then I can assume all is well with the left door’s wiring and speakers.
The question is, is it safe for the speakers voicecoils and associated coils and especially the capacitors to simply test by connecting the Multimeter to the + and - at the Amplifier connector block?
Could I damage anything within the left midrange speaker channel?