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Multiple inputs to active speakers

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Multiple inputs to active speakers

Postby Moroccomoose » Wed Oct 14, 2020 11:09 am

I have a pair of KRK Rokit 6s as my studio monitors. They have three inputs on the back; Balanced XLR, Balanced TRS and unbalanced RCA. They are permanently connected to my interface via the XLRs.

In Covid times, my studio desk has become my work desk so for music, I am using Spotify from my phone(which uses much less electricity than my studio PC and interface) and connecting it via the headphone jack to the the RCAs left and right. I am not unplugging the XLRs. I have the 3.5mm RTS for the headphones socket as a flying lead when not connected to my phone, ready to plug in as and when.....

I am aware this is a crude arrangement, so interested to know if I could cause damage.

Cheers,

Stu.
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Re: Multiple inputs to active speakers

Postby Hugh Robjohns » Wed Oct 14, 2020 11:47 am

It is not clear how the different inputs are handled inside the KRK and my policy is always 'if in doubt, don't!'...

In general, there is a potential risk to the output drivers of devices if they are connected directly in parallel as one device effectively tries to force current 'the wrong way' into the other device! And often devices with multiple unselectable inputs have those inputs wired directly in parallel.

In this case, though, while the TRS and XLR sockets may well be connected in parallel, it's likely that the unbalanced RCA inputs feed into a different part of the circuitry after the balanced input stage.

So on balance, I'd expect you to be able to use the RCA inputs quite happily from your phone... but I'd probably only do so when the interface feeding the balanced inputs was turned off, just to be safe! Similarly, I'd disconnect the phone when using the interface inputs.
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Re: Multiple inputs to active speakers

Postby Moroccomoose » Wed Oct 14, 2020 3:37 pm

Thanks Hugh,

I'll be careful!

Stu.
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