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Discussion Starter #1
Question for electrical engineers here.. is this possible to do? Would it work if I used a Y splitter to combine the two stereo lines into one and then another to split them?

This is to drive sub woofer amp does does not sum signals of its inputs. I don't feel confident enough about splitting one channel only into two.
 

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I don't quite understand what you're trying to say.

The signal in an RCA isn't stereo or mono, because it all comes from a source. The RCAs just carry said signal.

That's right. Assume the source sends a stereo signal on two sub outs. The amp expects mono signal on both sub ins.
 

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You don't want to combine two outputs with a Y-cable as it would cause the output stages to fight each other.

You can do it as simply as using a resistor on each leg. I have a headphone amp that has 3 inputs mixed using resistors.

The Y-cable to split is OK if they are going to the same piece of equipment. Splitting to multiple pieces of equipment can cause ground loops unless there is some isolation between them.



Paul
 

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You don't want to combine two outputs with a Y-cable as it would cause the output stages to fight each other.

You can do it as simply as using a resistor on each leg. I have a headphone amp that has 3 inputs mixed using resistors.

The Y-cable to split is OK if they are going to the same piece of equipment. Splitting to multiple pieces of equipment can cause ground loops unless there is some isolation between them.



Paul
more than that, you can blow out the op amps that way. this is no different than taking two amplifier speaker output and just wiring them together for more power. not only will it not work, but it will destroy your amp (it will go into protect more than likely)
 

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What sub amp are you using that doesn't sum its channels? If it is actually a stereo amp being used to drive subs it should be summed when you use the bridged outputs, if it is a mono amp it would have to sum the inputs. Unless you are running a very rare design this should be no problem.
 

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Discussion Starter #11
What sub amp are you using that doesn't sum its channels? If it is actually a stereo amp being used to drive subs it should be summed when you use the bridged outputs, if it is a mono amp it would have to sum the inputs. Unless you are running a very rare design this should be no problem.
MB Quart ONX1. The manual clearly states that you can't use stereo outs. It says you should take one and split it with a Y splitter. In addition the Q series and REF series amps state the same. On the other hand, the Discus series manual clearly states that stereo out are ok (Discus was replaced by ONX1, and supposedly ONX1 was meant to be "Discus improved"). Man, I am really disappointed I must say. I really wanted to give MB Quart a chance, but if I don't figure this one out, I will have to return it and get something from a less lazy manufacturer.
 

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does your HU have the ability to select the sub out to "mono"?
 

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I would have to say that the only reason for an amp to be designed that way is to save a penny (or less) in production. A very odd design, since it would take just a few resistors to isolate the channels and avoid any issues.
 

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MB Quart ONX1. The manual clearly states that you can't use stereo outs. It says you should take one and split it with a Y splitter. In addition the Q series and REF series amps state the same. On the other hand, the Discus series manual clearly states that stereo out are ok (Discus was replaced by ONX1, and supposedly ONX1 was meant to be "Discus improved"). Man, I am really disappointed I must say. I really wanted to give MB Quart a chance, but if I don't figure this one out, I will have to return it and get something from a less lazy manufacturer.
Maxxsonics gotta love em!:rolleyes:
 

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Discussion Starter #15
Well, if you've got a monoblock amp, you can use a full range signal on it and the amp itself will filter anything because of the built-in low-pass filter.

As it's been already mentioned, Y-ing 2 RCAs into 1 is bad; don't do it.

You COULD, however, Y-split those 2 RCAs into 4.
I think you still have not understood why I started this thread. The amp has two RCA plugs. Both need mono signal. The head unit sends stereo signal on RCA outs. Don't you see a problem there?
 

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Discussion Starter #18
I don't quite understand what you're trying to say.

The signal in an RCA isn't stereo or mono, because it all comes from a source. The RCAs just carry said signal.
The signal is stereo. When you connect your RCA cables to L and R plugs, it's stereo right. The source, as expected sends left channel information on L and right channel information on R. The amp needs mono signal on both plugs.
 
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