Here's one for you. Whilst experimenting with Bi amping my system I noticed that the speaker terminal markings on my pair of NAD 2200PE's were different.
1) Has both positive + terminals in the middle, next to each other (red binding posts) with the negative - terminals either side of them in a row of four with right channel first. Reading from left to right: negative positive positive negative (As per the manual)
2) The other reads as follows: positive negative positive negative (not as per manual). And the binding posts are all black
This caused me to get the old continuity tester out and check out the circuits. Now I beleive the negative terminals are grounded eg to the chasis and outer casing? In amp 1) this is the case where as in amp 2) the first positive (reading left to right above) is indeed grounding suggesting it is wired as a negative? as is the last negative, which reads as marked. With the two middle terminals reading as positives.
So..i have switched the polarity for this one channel on amp 2) and all seems to sound fine and not out of phase. Don't know if there are any other ways of checking correct amp polarity, without getting too technical
1) Has both positive + terminals in the middle, next to each other (red binding posts) with the negative - terminals either side of them in a row of four with right channel first. Reading from left to right: negative positive positive negative (As per the manual)
2) The other reads as follows: positive negative positive negative (not as per manual). And the binding posts are all black
This caused me to get the old continuity tester out and check out the circuits. Now I beleive the negative terminals are grounded eg to the chasis and outer casing? In amp 1) this is the case where as in amp 2) the first positive (reading left to right above) is indeed grounding suggesting it is wired as a negative? as is the last negative, which reads as marked. With the two middle terminals reading as positives.
So..i have switched the polarity for this one channel on amp 2) and all seems to sound fine and not out of phase. Don't know if there are any other ways of checking correct amp polarity, without getting too technical