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Connecting multiple amplifiers to one input

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I'm using a Y-adapter from the headphone jack of my iMac Pro to my powered main speakers (Genelec 8341a) and a subwoofer (KEF KC62). As I understand it, modern devices don't draw much current. I'm not detecting any ill effect from this, but I could be missing something.

For my Sennheiser HD650s I want to add yet another amplifier such as a Topping headphone amp. How would you go about this? Is there a downside to using yet another Y adapter?
 

raindance

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It's got more to do with output impedance and voltage swing than current delivery. Try it. If it works and isn't bass-shy it's probably ok. You can also try connecting two of the devices while you are listening to one and see if the level drops.

BTW, all three devices will need to be powered on all the time when in use otherwise you may get clipping.
 

Kal Rubinson

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For my Sennheiser HD650s I want to add yet another amplifier such as a Topping headphone amp. How would you go about this? Is there a downside to using yet another Y adapter?
The downside is that each of the devices connecting to that input will load the other (i.e., its output impedance will be seen in parallel to the input impedance of the target device). That may not be entirely destructive but it is likely to have a significant effect on the sound of the other source and that effect will be different depending on whether the currently unused source is powered on or off.
My advice is to get a simple switch.
 

Weeb Labs

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I'm using a Y-adapter from the headphone jack of my iMac Pro to my powered main speakers (Genelec 8341a) and a subwoofer (KEF KC62). As I understand it, modern devices don't draw much current. I'm not detecting any ill effect from this, but I could be missing something.

For my Sennheiser HD650s I want to add yet another amplifier such as a Topping headphone amp. How would you go about this? Is there a downside to using yet another Y adapter?
This should not present a problem. Both the headphone amplifier and your speakers exhibit an input impedance of around 47K Ohms, which is typical of buffered inputs but there is a more elegant means of doing this.

My suggestion would be to make use of the preamp passthrough outputs on this hypothetical Topping amplifier, as that will simplify volume control and eliminate the need for an additional splitter.

Your KC62 also possesses a crossover passthrough, so you could simply connect the Genelecs directly to its output and eliminate your current splitter. This is actually the preferred configuration because it provides a proper crossover for your speakers.

1624459025664.png


The signal chain would be:
iMac Pro -> Topping (L30?) + HD650 -> KC62 -> Genelec

No splitters are required and you can seamlessly switch between speakers and headphones via the L30's mode selector, controlling volume for both with the same knob.
 
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This should not present a problem. Both the headphone amplifier and your speakers exhibit an input impedance of around 47K Ohms, which is typical of buffered inputs but there is a more elegant means of doing this.

My suggestion would be to make use of the preamp passthrough outputs on this hypothetical Topping amplifier, as that will simplify volume control and eliminate the need for an additional splitter.
OK.

Your KC62 also possesses a crossover passthrough, so you could simply connect the Genelecs directly to its output and eliminate your current splitter. This is actually the preferred configuration because it provides a proper crossover for your speakers.
Unfortunately the KC62 sends a popping sound and static noise to its outputs when it turns on automatically.

I am thinking maybe the new Topping EX5 would be a nice way to go? It seems a shame to waste the balanced inputs to the Genelecs.
 

Krs89

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I'm in a similar situation.
My current desktop setup is:
Mac -> FiiO K9 Pro (AKM) -> Soundimpress PU400 Eigentakt -> KEF LS50M
I want to add the KC62 sub, but neither my DAC nor my power amp has a sub out. I'm using balanced XLR cables to connect the DAC to the Amp and would like to keep it this way. (I'm living on the top floor of a building, there are antennas on the roof, and my previous active speaker setup had a nasty RF interference problem)
I am new to this, but so far, I think my options are the following:
- Get a DAC or Amp with sub out (I just purchased my power amp, and I'd like to keep it)
- Get a balanced MiniDSP 2x4 Flex

Are there any other solutions I'm not aware of?
Maybe I shouldn't worry about it and simply connect the DAC to the KC62 with RCA, then RCA back to the power amp?
 

staticV3

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I am thinking maybe the new Topping EX5 would be a nice way to go?
The SMSL DL200 does the same for half the price.
Or even the M300 SE if you're fine with a not quite as powerful headphone amp and that brick-like form factor.
 
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