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Gareth Magennis Gareth Magennis is offline
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Default Monitoring the signal going into a non-grounded speaker?


"N_Cook" wrote in message
...
Gareth Magennis wrote in message
...

"N_Cook" wrote in message
...
Without differential scope amplifier/probe, audio out is missing

something
in the bass range about 70-80 Hz. Line-out signal faithfully follows
the
bass guitar input signal . Shure microphone, capable of those

frequencies,
monitoring the sound from the speaker, does not match the input at
those
sort of frequencies. But is it a failing of suspension or something of

the
speaker or some inductive/capacitive interaction with the amplifier
when
loaded with the speaker?
Not yet monitored the main rails to see if dipping on this bass amp.
I will then be subbing the speaker, as a test, but it still would not
determine whether an amp or a speaker problem , speaker is original to

the
combo. Any simple component to put in series or parallel with the

speaker
to
check if an output matching problem ?




Does this amp have a graphic equaliser? The line out may be pre graphic,
and one graphic fader may be faulty.



Gareth.




Volume , tone controls etc are in the DSP sextion and as line out is fine
,
I assume not a problem in that piece of magic.






Is this a Line 6?



Gareth.