I have an old Steinberg MR816csx as my audio interface on my mac. It has 8 outputs. My main speakers are 1,2 and my subwoofer is 3,4. I can only send audio to 1,2 on my mac - there’s no way to circumvent this, trust me - I’ve tried the aggregated device and multiple outputs - no go…
BUT, when I use JRiver, it allows me to change the outputs to 4 and Voila, the sound come out 1,2,3,4 - so I utilize the sub.
Is there a way to do this in Roon?
this is what it looks like in JRiver:
I suppose you are using the control software to set the audio output of the device.
According to the manual, you can set in MR Editor the output channels:
wow, you looked up the manual! that is a good person! thanks for the effort!
I am very, very familiar with the control software. The issue is my computer only sends audio to 1 - 2. It doesn’t send it to 3-4. I wish I could configure my Imac to send audio to all 8 outputs, but I can only send to 2 at a time. I’ve tried everything.
I also do home home recording, and in my DAW I can send audio to all 8 outputs and then I can use the control software to change the settings of all the outputs, but I cannot do that in OSX. Maybe there is a software I can get that will…I’ll look around.
It’s probably a limitation of the MR816. Some audio interfaces let you do this easily. you can “mirror” channels 1 -2 with 3-4.
Thanks again.
I am sorry, I did not want to offense you !
I am also using Focusrite audio interface and I can set the outputs via control software.
But I am using windows for that.
Best regards !
No no. No offence at I. I really appreciate it!
Oh, and I would love a focusrite! Nice gear.
I am not sure if this could be the solution for you: rogueamoeba loopback
Thanks! I’ll take look. This my be exactly what I’m looking for.
Won’t be able to try it for a week os because of travel. Can’t wait to try it though. I will certainly report back in case this can help others.
Thanks again.
Along similar lines, there is a piece of software called Blackhole which may do what you need.
another one to look at - thanks! So glad I posted.
THE EASY WAY (PROCEDURAL / IIR EQ)
Under device settings.
Set the device as Multichannel mixing: 7.1, 5.1, 2.0
Note, Roon only offers options for 8 output, 6 output, and 2 ch output USB interfaces. 4 channel devices don’t work…
Select channel mapping only.
Use the Roon DSP engine.
Insert a Procedural Mix function. Mix stereo to the channels required, by select the correct input for each output. Up to 8 can be assigned.
Then simply insert the Procedural EQ required, and assign it to the channels needed. Multiple Parametric EQ’s can be applied here, to any combination of channels. I.e. this is where you insert a high pass on channel 1 and 2, and low pass your subs, I.e. channels 2 and 4.
You should now have a working crossover. No need for loopback, inside your interface. The interface should be set to 1 to 1, straight through, with USB audio assigned to the channels.
THE MORE DIFFICULT WAY (CONVOLUTION / FIR EQ)
Use the Roon’s convolution engine, to assign crossovers, channel route and EQ.
The benefit of this method is you can correct for phase/time also.
Convolution doesn’t require the procedural mix routing, as channel routing is addressed using the config file in the convolution you create.
This is much more complex procedure.
So after setting your device as 7.1/5.1, 2 with channel mapping, insert a convolution filter instead.
For instance this is my JBL M2 crossover.
Convolution wav’s have been created at all required sample rates, accompanied by .cfg files for each sample rate. Roon uses the .cfg files to direct traffic, and select the correct convolution files.
Structure of a “typical” 2 way convolution filter.
Inside the “.cfg”
This is where convolution wav’s are channel assigned.
The Roon convolution overview provides a basic overview only.
Top line of convolution .cfg…
96000 2 4 F
= 96000khz (.cfg is used for 96,000 sampling
= 2 = 2 input channels
= 4 = 4 output channels
= F - Hexadecimal channel assignment for interface, pushing EQ’d routes to channel 1,2,3,4 (On my 10 channel interface)
Typical users use a combination of REW and Rephase to create convolution files, and manual know how to create the .cfg. Programs such as Audiolense can measure, EQ and create the convolution in one package.
I hope this helps.
EXTERNAL DSP OPTION
Another way you could do this (As your interface is 4 channels) is do a loopback on PC, and EQ using CamillaDSP. How to for each platform here: CamillaDSP
I use CamillaDSP on a Pi4 to perform crossovers for my JBL’s when using LMS.
RPi4 + CamillaDSP Tutorial | Audio Science Review (ASR) Forum
Fantastic! Thanks!
Finally getting around to trying this and I don’t have the Chanel layout option…I see this?
I think it doesn’t work because Roon doesn’t know the details of my device…it has 8 outputs, but Roon thinks it just has 2. I tried to route left to output 3 and right to output 4 which should send sound to the sub, but it doesn’t.
this loopback software certainly gets the job done - real easily too! (but it’s $104 USD - yikes…I’ll have to see if having my sub is worth it ")
thanks
Ended up buying the Loopback software from Rouge Ameoba. Merry Christmas to me I guess. It’s a pretty slick and useful software. I have already found other uses for it.
@grizaudio Hello, is there any way to use Roon DSP for Center channel extraction from a 2.0 signal?
I also have a MiniDSP Flex if that would help.
Thank you
Cenk
Do you just mean combined stereo?
If so yes. Just use the procedural matrix to combine channels.
MiniDSP would also allow this, assuming you have spare outputs.
Hello. not sure about terminology. It’s a digital filtering where common signals of L and R are extracted and diverted to a 3rd center channel. Basically sound which only constitutes the center phantom image of a stereo track. Not mono, as that would also include signals panned to only L and only R. I’ve found mixing apps which can do this on a file based system, but not real time for streaming. 
not sure if I managed to explain.
There is no centre channel creation function that I’m aware of. But you could possibility combined L&R stereo and band pass limit the frequencies as desired.
Try playing with the procedural engine.
I’ll try that. Thank you
