I'm trying to add my subwoofer to my desk setup. I have an RME ADI-2 DAC. My subwoofer has only 1 XLR input available for use.
Most hifi dacs/preamps only have stereo outputs. Only things like minidsp and some more expensive exotic units actually have dsp and multiple outputs. It's very rare to find and I haven't seen too many.
I don't want to buy a different DAC/amp for this setup. I also don't want to introduce more devices, particularly analog or digital crossovers. So I will run the mains at full range and use the subwoofer's built in crossover to match the mains at full range. The theory is that my mains already sound great, and so I will just try to extend the range further down with the sub.
The difficulty with this setup is that I only have one XLR input of my subwoofer available. I will for sure use XLR to the mains, as they are studio monitors and they don't accept unbalanced connections. This means I have to either split the 2 channel XLR L/R into 3 channel L/R/MonoSum or use the RCA's, sum them, and add an XLR adapter.
This is surprisingly obscure and difficult problem to solve.
I first looked up if it were possible to split my XLR into 3 channels. I could not find any simple device which does this. Analog crossovers will, but I don't want to use a crossover. Probably also some expensive pro audio mixer could do it, but that's super overkill. Also more devices, and cables no thanks..
I looked up cables. You can buy XLR Y splitter cables pretty easily.
I even managed to find a guy who makes XLR summing cables. http://micmodkits.com/other/
So you could in theory make some awful net of split and join cables, but that's also a very very bad idea. See this article.
https://www.prosoundweb.com/why-not-wye/
So I've given up on somehow ripping out a summed mono signal from the XLR's. How about the RCA's?
Again the problem here is I need to sum the rca signal. I also need to add an xlr adapter, which I have. There are several pro audio DI (direct inject) boxes out there which will take 2 rca's and sum them into an XLR balanced mono signal. They are passive devices, so assuming they are built well they should not add any noise to the signal. The problem with all of these is that they produce a microphone level input and not a line level input.
That same guy who makes the XLR cables also makes RCA sum cables. I found a few other companies who make these as well.
Finally, after a long search I stumbled onto this: https://www.sweetwater.com/store/detail/ISOPOD--whirlwind-isopod . This will sum an rca connection, convert it to balanced, and produces line level.
So in the end for this setup I think either the RCA sum cable or this isopod device is exactly what I need. I'm going to try the isopod, as having the ability to convert the signal to balanced could help if I move the sub farther away in the room and need to do a longer cable run.
Am I overlooking something? Does anyone see a reason why this wouldn't work?
If you've successfully integrated a sub into a system using a standard 2 channel hifi dac/amp how did you pull it off?
Most hifi dacs/preamps only have stereo outputs. Only things like minidsp and some more expensive exotic units actually have dsp and multiple outputs. It's very rare to find and I haven't seen too many.
I don't want to buy a different DAC/amp for this setup. I also don't want to introduce more devices, particularly analog or digital crossovers. So I will run the mains at full range and use the subwoofer's built in crossover to match the mains at full range. The theory is that my mains already sound great, and so I will just try to extend the range further down with the sub.
The difficulty with this setup is that I only have one XLR input of my subwoofer available. I will for sure use XLR to the mains, as they are studio monitors and they don't accept unbalanced connections. This means I have to either split the 2 channel XLR L/R into 3 channel L/R/MonoSum or use the RCA's, sum them, and add an XLR adapter.
This is surprisingly obscure and difficult problem to solve.
I first looked up if it were possible to split my XLR into 3 channels. I could not find any simple device which does this. Analog crossovers will, but I don't want to use a crossover. Probably also some expensive pro audio mixer could do it, but that's super overkill. Also more devices, and cables no thanks..
I looked up cables. You can buy XLR Y splitter cables pretty easily.
I even managed to find a guy who makes XLR summing cables. http://micmodkits.com/other/
So you could in theory make some awful net of split and join cables, but that's also a very very bad idea. See this article.
https://www.prosoundweb.com/why-not-wye/
So I've given up on somehow ripping out a summed mono signal from the XLR's. How about the RCA's?
Again the problem here is I need to sum the rca signal. I also need to add an xlr adapter, which I have. There are several pro audio DI (direct inject) boxes out there which will take 2 rca's and sum them into an XLR balanced mono signal. They are passive devices, so assuming they are built well they should not add any noise to the signal. The problem with all of these is that they produce a microphone level input and not a line level input.
That same guy who makes the XLR cables also makes RCA sum cables. I found a few other companies who make these as well.
Finally, after a long search I stumbled onto this: https://www.sweetwater.com/store/detail/ISOPOD--whirlwind-isopod . This will sum an rca connection, convert it to balanced, and produces line level.
So in the end for this setup I think either the RCA sum cable or this isopod device is exactly what I need. I'm going to try the isopod, as having the ability to convert the signal to balanced could help if I move the sub farther away in the room and need to do a longer cable run.
Am I overlooking something? Does anyone see a reason why this wouldn't work?
If you've successfully integrated a sub into a system using a standard 2 channel hifi dac/amp how did you pull it off?
Last edited: