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Harmon Kardon Go Play Plus Sub? Possible

LilSizzle

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Feb 6, 2022
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Hello legends,

Me again with a fun question.

I want to split a signal in two and drive it into a Harmon Kardon Go Play II and then into a Polk DSW PRO 440wi Sub for the bass. Just like having a sub ready to jack into for that extra lower end kick.

The gear:
HK GO Play - input 3.5mm
Polk DSW PRO 440wi - RCA inputs

Thinking to literally use a 3.5mm male into two 3.5mm female.Then connect into the sub and Go Play.

Crazy idea? Better ways to do it?

Goal? Just to get some extra bass kick for dance sessions.

Also, why does the Polk Sub have speaker out terminals? Can they be used to drive speakers or only another sub?

I know this is a audiophile place and not such a top notch question, so feel free to say your bit, I just love the responses and sense of community here.
 
D

Deleted member 43441

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Hi, in my experience I’ve had better luck with a dedicated passive splitter box, than a Y cable.

I purchased a quality RCA splitter box from eBay, it’s actually from an American seller and I use it all the time. One input to six outputs i believe, and the manufacturer of the backs even told me that it was tested, and I believe he said you lose two or three Db from the split. I don’t see why it would be any different with a 3.5 mm jack. Not that there’s anything wrong with a Y cable, just for me the splitter box was better.
 

staticV3

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Assuming that both inputs have a high enough input impedance, and your output has a low enough output impedance, you shouldn't lose anything by splitting the signal with a simple y-split.
My recommendation would be to use something that's intended to drive headphones. Something like the Apple or Meizu dongle with its 0.1Ω output impedance.
 
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Deleted member 43441

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I believe the splitter cuts voltage in half, and I would look into that. Definite adjustments are needed if you want to get the equal signal to each leg off the splitter. Splitters never split the signal equally, I’m pretty sure they cut the voltage in half. That’s why I used the passive splitter box, you don’t lose as much in my experience.
 

staticV3

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I believe the splitter cuts voltage in half, and I would look into that. Definite adjustments are needed if you want to get the equal signal to each ouput of the split. Splitters never split the signal equally, I’m pretty sure they cut the voltage in half. That’s why I used the passive splitter box, you don’t lose as much in my experience.
It doesn't. Harman speaker and sub would be connected in parallel.
 
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Deleted member 43441

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It doesn't. Harman speaker and sub would be connected in parallel.

Can you get matched output from a splitter? Interesting, I have always understood it splits everything in half. Unless the parallel part has something to do with it, I’m always willing to learn, so thanks for responding.
 

EdTice

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Can you get matched output from a splitter? Interesting, I have always understood it splits everything in half. Unless the parallel part has something to do with it, I’m always willing to learn, so thanks for responding.
Splitting does nothing to voltage. The voltage remains the same and is seen by both devices. It lowers the impedance which results in greater current draw on the source which is fine if the source can provide sufficient current. Most pre-outs can drive relatively low impedance loads. So if the net impedance of the two subs is still greater than the minimum impedance specification of the output it will be fine.
 
D

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Splitting does nothing to voltage. The voltage remains the same and is seen by both devices. It lowers the impedance which results in greater current draw on the source which is fine if the source can provide sufficient current. Most pre-outs can drive relatively low impedance loads. So if the net impedance of the two subs is still greater than the minimum impedance specification of the output it will be fine.

So is it your belief that you get exactly the same signal from both legs of a split cable, Or is it degraded/weakened somehow?

That’s my point, you can’t split a signal in half and have it the same as it was before, unless it’s enhanced
 

EdTice

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So is it your belief that you get exactly the same signal from both legs of a split cable, Or is it degraded/weakened somehow?

That’s my point, you can’t split a signal in half and have it the same as it was before, unless it’s enhanced
You are failing to read the previous posts with comprehension. When you split a cable from an output, this lowers the impedance. If the new, lowered impedance is still within the specifications of the output device, the signal will be "enhanced" to user your terminology. This will happen because the output device (in this case the subwoofer pre-out) will deliver more power because that's how voltage devices work. Specifically if you take the signal to one subwoofer and split it so that it is now sent to two identical subwoofers, the impedance will be exactly half. And the power delivered will be exactly double! So each subwoofer will see the original voltage and original power.

In the case where the splitting of the signal causes the parallel-circuit impedance to be below the minimum impedance that the source can drive, you will have much worse problems than signal degradation. You might actually break the source equipment or even start a fire.

However, you would have a *very* difficult time finding a piece of home audio equipment that can't drive two subwoofers for a variety of reasons. If you ever look at a subwoofer, most of them have "pass throughs" for hooking up a second sub. Those don't enhance the signal. They are really nothing more than a Y connection in most cases.

For long cable runs, you sometimes need signal enhancement because the impedance of the cable might result in *too little* power being delivered. The opposite can also happen where splitting a signal results in impedance too low for the source device to drive (discussed earlier) In that case you will need a device that can maintain voltage but provide higher power. This is the case when "distribution amplifiers" are needed.

Even in cases where splitting the signal would result in a too-low impedance (due to excess power requirements) that would happen only near maximum output levels. With active subwoofers, each added speaker means the necessary output voltage to achieve the same in-room volume drops by sqrt(2). So unless you hook up like twenty of them this way and turn all of the volumes way down to where the DAC has to run the subwoofer output at +10dB, its still likely to not be an issue.
 
D

Deleted member 43441

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You are failing to read the previous posts with comprehension. When you split a cable from an output, this lowers the impedance. If the new, lowered impedance is still within the specifications of the output device, the signal will be "enhanced" to user your terminology. This will happen because the output device (in this case the subwoofer pre-out) will deliver more power because that's how voltage devices work. Specifically if you take the signal to one subwoofer and split it so that it is now sent to two identical subwoofers, the impedance will be exactly half. And the power delivered will be exactly double! So each subwoofer will see the original voltage and original power.

In the case where the splitting of the signal causes the parallel-circuit impedance to be below the minimum impedance that the source can drive, you will have much worse problems than signal degradation. You might actually break the source equipment or even start a fire.

However, you would have a *very* difficult time finding a piece of home audio equipment that can't drive two subwoofers for a variety of reasons. If you ever look at a subwoofer, most of them have "pass throughs" for hooking up a second sub. Those don't enhance the signal. They are really nothing more than a Y connection in most cases.

For long cable runs, you sometimes need signal enhancement because the impedance of the cable might result in *too little* power being delivered. The opposite can also happen where splitting a signal results in impedance too low for the source device to drive (discussed earlier) In that case you will need a device that can maintain voltage but provide higher power. This is the case when "distribution amplifiers" are needed.

Even in cases where splitting the signal would result in a too-low impedance (due to excess power requirements) that would happen only near maximum output levels. With active subwoofers, each added speaker means the necessary output voltage to achieve the same in-room volume drops by sqrt(2). So unless you hook up like twenty of them this way and turn all of the volumes way down to where the DAC has to run the subwoofer output at +10dB, its still likely to not be an issue.

OK I comprehend this one haha. In my experience things get lost with splitting, that’s why I have three subwoofers daisychained. I may have leaped before I looked on this one LOL

Anyway thanks!
 
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