Seems tough to ensure only subwoofer is playing bass frequencies (& not the main speakers)


Given that the bass from main speakers will be qualitatively different than the bass from a subwoofer...  I do not want  them both playing the bass frequencies. Seeking help in this quest of mine to ensure only the sub plays the bass. 

**My Setup:**
- Source: Oppo UDP 205
- DAC : Black Ice Audio  Glass FX  (fyi: it has volume control)
- Integrated amp: Primaluna Dialogue Premium HP.  (no pre-outs, but has high level mono out and also HT bypass mode)
- Subwoofer: Velodyne DD+ 10 inch.  

Without the DAC in the picture, its pretty easy. The Oppo has bass management & dedicated sub output. This allows using the oppo for master volume control.

How can I use an external DAC (instead of whats built into the oppo) for both the  and continue to send bass frequencies to the sub but not the main speakers ? 

one thought i have is.. it will need introducing an external digital cross over as follows :

Oppo -> DAC -> Cross over -> Subwoofer & Integrated amp

In which case i suppose I would have to use the volume control on the DAC ?
roxito
m-db and elliottbnewcombjr, thanks very much for pointing out the high pass output feature in the sub.

I think its possible to connect it up as follows:

(full range) Line level output from Dac => Rca inputs on subwoofer => High pass line level output => integrated amp => speakers.

I can use the volume control on the dac. Should be able to continue to use the EQ and room optimization in the Velodyne sub.

millercarbon, I will A/B the mains running full range v/s partial range in this new setup. In my existing setup where the Oppo does the bass management, setting the main speakers to "small" worked better.

I would just connect the subwoofer using its high-level speaker inputs connected to the integrated amps speaker terminals.  Adjust the crossover on the sub so it underpins the main speakers as well as adjust the sub volume control properly so as the volume on the integrated is adjusted, everything stays as one cohesive system.  Super easy and this is how I've been connecting subwoofers for decades.  Mains = full range.  Subwoofer = support/ supplement for the lowest registers below the mains.
I also run my speakers full range (down to 20hz) and reinforce the bottom end with an audio Kenesis swarm inspired subwoofer setup (two additional subs). The subs play from 16-80ish hz and integrate really well. If you can echolocate them, something is setup incorrectly (i.e., either volume or the sub's low pass filter cutoff).  

As you can see, there are lots of ways to play the game even with your current setup. Try them all and choose the winner. Do note that people tend to over cook their sub volume levels because they like to hear thump coming directly out of the unit. This ruins integration with the main speakers.
I've done both, with my Parasound HINT which has bass management system I can high pass mains and low pass the sub. Running the mains full range gives me the best full range sound with my sub. I like the bass from my mains so why would I cut them off?? You lose some dBs cutting the mains and a bit of detail from the lows as you don't want to hear anything from the sub but you do want what it adds to say the stand up bass.
I have the HINT low pass at 40Hz, volume at about 50% and phase at about 130 deg on the sub. I can put my ear about 12-18" from my sub and I don't hear anything, if I turn the sub off its the same but a bit less low end detail and volume.
My mains have 8" woofers so why would I want to reduce the amount of air I can move by only using the subs 12" driver?
I think running your mains full range is the best way to go.