Hi.
Opened my Denon PMA1600NE last week, I saw 2 small capacitors between the output binding posts, 2 x 1100pF (green 112J) between each speaker output terminal and case chassis, there is also 1 x 332J (3300pF blue) between positive speaker terminal and earth on each output.
Anyone know why these are there? I do not see these on my other 2 amplifiers.
Lastly, when looking at my speaker crossover, I noticed a small inductor (in series) on the end tweeter circuit before the + wire to the speaker. The inductor comes after the series capacitors and padding resistor and is in series (last component) before leaving the board to the tweeter, Never seen that before, the Speaker is Elac ubr ref.
Thanks in advance.
Opened my Denon PMA1600NE last week, I saw 2 small capacitors between the output binding posts, 2 x 1100pF (green 112J) between each speaker output terminal and case chassis, there is also 1 x 332J (3300pF blue) between positive speaker terminal and earth on each output.
Anyone know why these are there? I do not see these on my other 2 amplifiers.
Lastly, when looking at my speaker crossover, I noticed a small inductor (in series) on the end tweeter circuit before the + wire to the speaker. The inductor comes after the series capacitors and padding resistor and is in series (last component) before leaving the board to the tweeter, Never seen that before, the Speaker is Elac ubr ref.
Thanks in advance.
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Yes I'd agree, to keep those pesky phone and WiFi signals out of the enclosure - you might thing the output terminals are low impedance, but at RF they won't be without those caps, and a speaker cable makes an effective long-wire antenna...
Thanks, I guessed they might be something to do with that, just not seen them before in my other amps.
Not sure if that white object is a ferrite, I didn't look properly at the time, I had to open the amp up to replace a damaged optical port on the digital board and just noticed the caps on the speaker output.
One thing I did notice is that when using a CB radio when I had my other amplifiers turned on and when I keyed up the mic it was bleeding through the amps to my speakers very loud, it doesn't do this when I had the Denon turned on so it appears the Denon has much better filtering and RF noise rejection.
Not sure if that white object is a ferrite, I didn't look properly at the time, I had to open the amp up to replace a damaged optical port on the digital board and just noticed the caps on the speaker output.
One thing I did notice is that when using a CB radio when I had my other amplifiers turned on and when I keyed up the mic it was bleeding through the amps to my speakers very loud, it doesn't do this when I had the Denon turned on so it appears the Denon has much better filtering and RF noise rejection.