SMSL AO200 - XLR or RCA but not both?

[melvinjames]

I've seen mention of this somewhere but couldn't remember exactly where. IIRC it was in reference to a Topping amp not SMSL. I searched ASR and Googled it as well and found nothing definitive, so I contacted SMSL support. Here's the reply:

"Generally we do not recommend that you connect XLR input devices and RCA input devices at the same time."

They provided no other explanation. I'm curious as to why it's not recommended. Anyone care to enlighten me and/or point me to a thread. Thanks.

 

[Slayer]

I've seen mention of this somewhere but couldn't remember exactly where. IIRC it was in reference to a Topping amp not SMSL. I searched ASR and Googled it as well and found nothing definitive, so I contacted SMSL support. Here's the reply:


They provided no other explanation. I'm curious as to why it's not recommended. Anyone care to enlighten me and/or point me to a thread. Thanks.

Simple: Because it only has one analog unput. So you have the option to choose balanced or single ended, but not both at the same time. Hooking both up i imagine would cause problems. If you were lucky it would just put the amp in protect mode, but it could do more serious harm.

 

[melvinjames]

The AO200 has input for both XLR and RCA and the inputs are selected through the menu. If only 1 input is active then why not have 2 sources connected, one of each for convenience if nothing else? Is this a circuitry thing .. balanced vs fully balanced? And what if 1 source was off or unplugged from power?

 

[Katji]

And what if 1 source was off or unplugged from power?

Then it is "not there."

 

[melvinjames]

Thank you both. @Katji .. I thought as much and appreciate the clarification.

 

[MaxwellsEq]

Depending on the design, unbalanced connections may cause the channel to no longer have similar impedance to ground (the screen causes the balanced connection to have ground on one input).

 

[Speedskater]

Depending on the design, unbalanced connections may cause the channel to no longer have similar impedance to ground (the screen causes the balanced connection to have ground on one input).

If that's about multiple input connections, then it's a very poor design.
But output connections are another story.