How to get a mono sub out from MSB?

[Brucemck2]

I am thinking of adding an MSB dac. My left/right have great response individually down into the low 20s, but, I have to use a mono sub crossing over around 40hz because the phases of my Left and Right cause bass cancelation down low, and too much bass is effectively mono in the L and R channels.

How do I get a mono subwoofer output from an MSB dac? (Or, will I need to add another summing device downstream of the MSB?) I see where I can easily add sub isolators, but those are “per channel” and I need to get to mono to feed my (five) subs.

 

[bryans]

Hmm the only option I can think of is using the MSB Sub Isolators and then a Y-cable to go mono into your sub.

 

[Jeffy]

Why not just buy another Balanced output module from MSB and add it to the DAC.

 

[Dustin Symanski]

Mixing any signal from stereo to mono without advanced digital algoritms to do so is a bad idea. Depending on original recording you can get huge frequency nulls in the mixed output. So either generate a separate sub channel with software or use just one output (Left or Right your choice) for your single sub.

 

[msimanyi]

I need to get to mono to feed my (five) subs.

Can you tell us a little more about the hardware and signal path you're using now, and where the MSB will be located in that topology?

 

[Brucemck2]

I currently go HDMI (modded AppleTV and BluRay), Ethernet (Roon/JRiver) and AES/EBU (also Roon/JRiver) into a Trinnov Altitude 32 which feeds my amps. I have a two channel preset that feeds my full range fronts and sounds great, and sounds even better when I use my five subs crossed over at 50hz. That being said, it doesn‘t sound as great in two channel mode as my prior dedicated two channel rig did.

I am thinking of adding a high end DAC (most likely MSB, or maybe, Lampizator) between the Trinnov and my amps, and would do volume control in the DAC. I would feed it directly from my Roon sources, or a Taiko or similar. For home theater and Atmos I would use the analog inputs on the new DAC and put it in bypass or unity gain mode. If I could get a mono sub feed out of the new DAC then I could still use my five subs. (I’ve got a separate kluge to feed the five subs when I was in home theater mode) One alternative would be to put a JL Audio CR2 or similar after the new DAC, but that is antithetical to the notion of a more purist signal chain from DAC to amps.

 

[msimanyi]

What inputs do you have on your subs, and of those which are you using? For example my subs have line level inputs, speaker level inputs and LFE inputs, all in both SE and balanced connections. I'm feeding LFE out of the processor to subs through a MiniDSP DDRC-88A, as well as speaker level to the two front left and right subs jumpered off my main speakers.

I'm wondering if there's some creative combo you could run in a similar manner.

 

[Brucemck2]

Currently mono out of the Trinnov into a QSC that feeds each of the five sub amps and then onto the subs separately. I could create another input and preset on the QSC, but I’d still have to get a sub feed going into the QSC.

One alternative would be to go digital out of the Trinnov into the new DACs, which would preserve my existing crossover functionality. But I’d be losing the opportunity to feed the DAC with a Taiko or similar which is a big part of the upgrade appeal as the Trinnov is unlikely to be a reference quality digital source.

 

[msimanyi]

I’m certainly no expert, and I’m still thinking about this, but the JL Audio CR1 might be a good solution.

Could you go Taiko -> DAC -> Trinnov -> CR1 -> QSC and L/R speakers?

I think that may do what you want. Set up the CR1 to be the crossover for two-channel, with the Trinnov in Reference mode. Dial in the CR1 to perfection in Reference, then re-sweep the Trinnov DRC for home theater modes so its pre-sweep baseline is the dialed-in CR1 configuration.

If, down the line, you feel the Trinnov is hindering playback, add a two-channel preamp with home theater bypass mode between the Trinnov, CR1 and L/R speakers, and have the Taiko+DAC input to the new preamp, along with any other two-channel sources you like.

There are a surprising - to me anyway - number of excellent preamps with that sort of bypass, including Pass Labs, VTL, MBL, Dartzeel and more.

There’s probably something horribly wrong in my thoughts above, but perhaps it strikes up some creative ideas for you.

Edit: I know it doesn’t simplify the chain for you, but it does allow coexistence of a properly crossed over and dialed in two-channel system with subs and the Trinnov controlling room correction for HT.

 

[Brucemck2]

That does not work as the whole idea is to get the Trinnov’s DAC out of the chain. In a prior incarnation I ran a VAC 7.5 after the trinnov with an MSB transport and DAC into the VTL as a way of bypassing the Trinnov, but in that instance I wasn’t using subs.

I think the way to do this is Taiko -> MSB DAC -> Preamp -> CR1 -> amps for high pass and CR1 -> QSC for low pass

 

[msimanyi]

Sounds like that would work.

I’m curious - what is the QSC hardware you’re using?

 

[Brucemck2]

110f

 

[Popspin]

I’m likely the wrong person to try to answer this but I was trying to integrate a Reference with my Trinnov. Wanted 2 woofers also.
Ended up with 2 separate systems. Source to MSB then direct into speakers. Woofers will be connected REL style. And a HT system with its own speakers and woofers.
Happy camper here still in the process but can see the light at the end of the tunnel.

 

[Brucemck2]

I think I’m going to go stereo out from the MSB into the QSC that manages my five subs and then set up a separate preset just for that. Time alignment isn’t an issue given placements so it should work ok