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Chops

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No sir. Even after a thorough Google search, I didn't come up with anything.

Is there something wrong with it?
 

Brad225

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No, I was speaking with my EE friend about the conversation about Balanced Amps connected to Subs via speaker input.
He said possibly, but, more than likely not. He would like to look at the schematic to answer my question.

I contacted ML and their response was that speakers and subs are not negative to ground so it is not an issue. I still would like to hear what my friend says. Worst case is I will open one of them up and he can take a look.

I have not had any issues with my amps so I doubt is matters, but, I can build furniture not audio equipment. :)
 
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Chops

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As I said in another thread, I ran the Schiit Aegir amps bridged mono into each sub without any issues, as well as a pair of PS Audio Stellar M700 monoblocks (which were true balanced from input to output), again with no issue.

Theoretically, you shouldn't have any issues in your setup either, but always good/safe to ask.
 

Robert D

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Running amps into powered subs with their own amps, how does that work? Im guessing that the power sticks so that you're running the woofer with both the built in amp and the external amp? Isn't that overkill? Some of these modern subs have 1000 watt amps on a single woofer. Adding in another 400 watts, danger in blowing that speaker or no real change in quality of sound?
 

18000rpm

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Running amps into powered subs with their own amps, how does that work? Im guessing that the power sticks so that you're running the woofer with both the built in amp and the external amp? Isn't that overkill? Some of these modern subs have 1000 watt amps on a single woofer. Adding in another 400 watts, danger in blowing that speaker or no real change in quality of sound?
You need a subwoofer that has high-level (ie. speaker-level) inputs. You would run two sets of speaker cables, one pair to speakers and one pair to the subwoofer. See Paul from PS Audio explain the reasoning here
 

Robert D

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If you run speaker wires from the amp to the subwoofer i dont understand how that wouldnt be using any of the power. Youd think that it would split the power between the front speakers and the 2 subs since there are 2 pairs of speaker cables attached to each L or R terminal. That would mean less power then going to the left and right mains.I guess somehow the sub only uses the signal and doesnt drain any power? My depth i has the speaker inputs on it. I just use my LFE sub out. Sounds great to me.

His suggestion of using RCA input for the sub and the balanced for your external amp sounds smart.
 
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Chops

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The high level input utilizes a high impedance on a powered sub. All it's doing is using the amplified signal from your main amp as just a signal, nothing else. It's not using power from your main amp to actually power the sub or add power to the sub, nor is it taking any power from your main amp (because of the high impedance).
 

Robert D

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The high level input utilizes a high impedance on a powered sub. All it's doing is using the amplified signal from your main amp as just a signal, nothing else. It's not using power from your main amp to actually power the sub or add power to the sub, nor is it taking any power from your main amp (because of the high impedance).
Ok, that makes sense. Did not know that. What would make that superior over running in a RCA plug? When you run RCA, thats still like a high level input isnt it? The signal is raw right out of the amp with no filter? Running them out of the RCA jacks for the front speaker jacks on the amp.
 

Chops

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RCA is low level, a max of possibly 2 volts or so depending on your preamp and signal. An amplifier's output is a lot higher than that, allowing longer distance runs without worry of noise being injected into the signal.

Also, I have yet to experience any ground loop hum with subs connected via high level inputs. One of my brothers kept having ground loop issues with his subs in his system. After I told him to try running the subs via the high level inputs, he hasn't had an issue since.

Lastly, for whatever reason, it seems that the built-in crossover controls on the subs seem to have greater range and control when fed via high level from the main amp, not to mention the subs will tend to take on the sound signature of the main amp as well for even better integration to the main speakers.

A LOT of people complain about that last bit because they say "you can't hear a difference in the bass below 80 Hz". That's total nonsense. And depending on how high up you run the sub's crossover point, this makes all the difference in the world, as well as running TRUE stereo subs like I am.
 

Robert D

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RCA is low level, a max of possibly 2 volts or so depending on your preamp and signal. An amplifier's output is a lot higher than that, allowing longer distance runs without worry of noise being injected into the signal.

Also, I have yet to experience any ground loop hum with subs connected via high level inputs. One of my brothers kept having ground loop issues with his subs in his system. After I told him to try running the subs via the high level inputs, he hasn't had an issue since.

Lastly, for whatever reason, it seems that the built-in crossover controls on the subs seem to have greater range and control when fed via high level from the main amp, not to mention the subs will tend to take on the sound signature of the main amp as well for even better integration to the main speakers.

A LOT of people complain about that last bit because they say "you can't hear a difference in the bass below 80 Hz". That's total nonsense. And depending on how high up you run the sub's crossover point, this makes all the difference in the world, as well as running TRUE stereo subs like I am.
So if I were to do it, I would run two sets of speaker wire from each terminal of my aragon amp? One speaker cable each to the Prodigy speakers and then another set to 2 subwoofers? Right now I have a nice set of speaker wires with spade connectors going to the Prodigy speakers. Perhaps use some banana plugs to run to the two subwoofers? I suspect that the speaker wire going to the subwoofer wouldnt have to be as high quality as that used for the main speakers?

I have never run two speaker wires from one terminal before and figure maybe using a spade and banana together would make it easier, and could save some money by not using highly expensive speaker wire for the sub.
 

Robert D

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Just checking, running RCA out from an amp would be a different signal than using the sub out jack, right? The sub out would have been filtered by the DSP of the receiver/pre amp, and the RCA out from the Left and right channel will be an untouched signal?
 

18000rpm

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Just checking, running RCA out from an amp would be a different signal than using the sub out jack, right? The sub out would have been filtered by the DSP of the receiver/pre amp, and the RCA out from the Left and right channel will be an untouched signal?
That's correct. But note that by not using the sub out, your receiver or pre-amp will be adding the LFE channel to your fronts also (technically to any speakers set to "large"). So for any content that has a discrete LFE channel it will go to your Prodigies as well instead of just the subwoofer.
 

Robert D

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That's correct. But note that by not using the sub out, your receiver or pre-amp will be adding the LFE channel to your fronts also (technically to any speakers set to "large"). So for any content that has a discrete LFE channel it will go to your Prodigies as well instead of just the subwoofer.
Ok. My Marantz has the ability to set the crossover point for every speaker. So if I didnt have the fronts set to large, the sub wouldn't get a signal below the crossover too, right? Right now i have the fronts set at 80 hz. So id have to have those set to large with no crossover? I let Audyssey set the crossover points and then make small changes to that. In this case I'd have to either not use Audyssey at all, or just over ride the fronts settings? End up getting into external crossover?
 

Chops

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So if I were to do it, I would run two sets of speaker wire from each terminal of my aragon amp? One speaker cable each to the Prodigy speakers and then another set to 2 subwoofers? Right now I have a nice set of speaker wires with spade connectors going to the Prodigy speakers. Perhaps use some banana plugs to run to the two subwoofers? I suspect that the speaker wire going to the subwoofer wouldnt have to be as high quality as that used for the main speakers?

I have never run two speaker wires from one terminal before and figure maybe using a spade and banana together would make it easier, and could save some money by not using highly expensive speaker wire for the sub.
That's all correct. No fancy speaker cables required for the signal to the subs.

Or if you wanted to, you could just run your good cables to your Prodigy's like normal, then run the basic speaker cables from the Prodigy's to the subs as well.
 

18000rpm

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Ok. My Marantz has the ability to set the crossover point for every speaker. So if I didnt have the fronts set to large, the sub wouldn't get a signal below the crossover too, right? Right now i have the fronts set at 80 hz. So id have to have those set to large with no crossover? I let Audyssey set the crossover points and then make small changes to that. In this case I'd have to either not use Audyssey at all, or just over ride the fronts settings? End up getting into external crossover?
Yes you are right.

Set your fronts to large, everything else to small. Both the Prodigy and subwoofer will get the full range signal, including LFE. Try to find a channel tester video and make sure when it plays the LFE channel you can hear it.
 
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