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<blockquote data-quote="Ales Dravinec" data-source="post: 39240" data-attributes="member: 11">Re: Loudspeaker to Line Level PadBennett,There are so many things that can &#039;go wrong&#039; when measuring output of an amplifier...#1 red terminal isn&#039;t always &#039;hot&#039;. It is always positive but may as well be hard wired to ground.#2 output may be &#039;bridged&#039; ... both hots#3 outputs may sit on a DC (think ICEpower)..the solution is a &#039;full balanced attenuator&#039; (H bridge ???), preferably with incorporated DC blocking caps in the measuring side.I will come up with schematic later on.Not &#039;obeying&#039; my suggestions may result in a spectacular circuit closures with almost unlimited current available to make some spectacular damage.Loading : 30 ohms on the output of the amp reminds me of a joke about the elephant and the flee. Do a &#039;load duck test&#039; separately to get the info, or connect serious dummy load on the output. It may not be as good and big as Langston&#039;s (he posted pics of his resistor bank somewhere a while ago), but still. I&#039;d do measurements with no load.With respect</blockquote>

[QUOTE="Ales Dravinec, post: 39240, member: 11"] Re: Loudspeaker to Line Level Pad Bennett, There are so many things that can 'go wrong' when measuring output of an amplifier... #1 red terminal isn't always 'hot'. It is always positive but may as well be hard wired to ground. #2 output may be 'bridged' ... both hots #3 outputs may sit on a DC (think ICEpower) . . the solution is a 'full balanced attenuator' (H bridge ???), preferably with incorporated DC blocking caps in the measuring side. I will come up with schematic later on. Not 'obeying' my suggestions may result in a spectacular circuit closures with almost unlimited current available to make some spectacular damage. Loading : 30 ohms on the output of the amp reminds me of a joke about the elephant and the flee. Do a 'load duck test' separately to get the info, or connect serious dummy load on the output. It may not be as good and big as Langston's (he posted pics of his resistor bank somewhere a while ago), but still. I'd do measurements with no load. With respect [/QUOTE]

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