Questions never stop ever, it seems.


Hello All,  is there any point, any discernable advantage, to go to the hassle of including your subwoofer in the signal path of a bi-wired speaker system? Assuming you have enough connections to pull it off or it's even possible.

As opposed to the more normal thought of using the hi pass filter in the subwoofer by running the signal out from the preamp to the subwoofer then running the subwoofer out to the amplifier.

I don't really see a clear way to do both, bi-wire and use that hi pass filter and maybe even potentially blowing everything into orbit if you connect things wrong. Any opinions or ideas? Thanks.

j
stereoisomer
@classdstreamer

I assumed that the line-level out from the sub was for daisy-chaining additional subs (for a DBA). Maybe this is sub-specific? 

This is correct. IME most powered subs do NOT have high pass capabilities. It is by far the exception than the norm.
So if the line-level out from the sub engages a high pass filter, it seems you can't daisy-chain subs for a DBA.
This is also correct unless the designer added a low frequency output. If you want to run a DBA it might be simpler and more cost effective to incorporate an external crossover and use subs that do not have a high pass filter out.
If I wanted to run a DBA, would I need an RCA splitter at the preamp?
This should work if you are using a sub that has a high pass filter
On the topic of connecting the sub to both the high and low level inputs (amp and preamp), I believe I read that Rel could do that in a home theater application. That is, the Rel could both extend a center channel, or R/L channels, to full range while also being connected to the LFE. 

OP, I may have misunderstood, but I don't know how/why you would connect a sub via speaker wire (high level) from the mains power amp that you are simultaneously high pass filtering with the sub. 

On bi-wiring the mains. It seems to me that you could still bi-wire the mains from the power amp, which is receiving its signal through the sub. 
I have never considered running preamp out to the sub, then RCA from the sub to the amp that powers the mains. The lag time from the mains and bass does affect me. Something new to look into.

I assumed that the line-level out from the sub was for daisy-chaining additional subs (for a DBA). Maybe this is sub-specific? So if the line-level out from the sub engages a high pass filter, it seems you can't daisy-chain subs for a DBA. If I wanted to run a DBA, would I need an RCA splitter at the preamp?
That is exactly how I have my system currently configured. Preamp Outs to Subwoofer In and Subwoofer Outs to the amplifier itself. That engages the hi pass filter and gives me some control options on the subwoofer but are you also saying the system is now bi-AMPED not just bi-wired? I'm just trying to make sure I understand here.

Yes.

You are using one amp, built into the sub, to drive frequencies from 20 Hz to 85 Hz and a different amp to drive frequencies from 85 Hz to 20k Hz. IOW you have broken the frequency spectrum (20 Hz - 20k Hz) into two segments ( Bi ) with each segment being driven by dedicated amplification (amped)

Hope this is helpful.
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 If it's crossed at 80 and a 6 or 12 db crossover is used, it is still going down to 30 hz.  The taper on the roll ON (not off) is still from 20 or so all the way to 80 and 80 begins to roll OFF from there @ either 6 or 12 db per octave. So running full range can work but most folks don't like the sound SIMPLY because the timing issue from the mains can't be delayed as easy as the DBA or Swarm system..

I've tried it with every system I've ever used or owned.. I gave up all the way 15 years ago. NO BASS in the monitors. It may be there but I don't use it OR I swap it for MB couplers..

Still you got BASS in the monitor cabinet.. It cannot be timed correctly..
The best you can do is DELAY the signal from the mids and highs...

I also understand the way people blend  their DBA is all important. The SQ is usually a lot better. USUALLY folks STOP there and call it good, because it is good. BUT for me I wanted BETTER.

No BASS in the monitors.. ZERO... NOW the monitors are 2/3 narrower because of it... AND they do actually disappear in a room a whole lot easier..

It is like being in the maestro position all the time not some of the time..

Regards
From what I see on the Sunfire website, your sub only has RCA input capability. So you run from your pre-amp to sub OR you run from your pre-amp to sub and back out of the sub to your main amp. The first way does not use the crossover in the sub, the second way does. 
It is preferable to run the mains full range and the sub additional to, not crossed over from.
Bi-wire has nothing to do with the subwoofer. You are bi-wiring from the amp to the main speakers. The line level goes out of the the preamp into the line in on sub then the from the line out of the sub to the input of the amp. Most subs have a fixed 80hz high pass filter. Bi-amping is when you use two power amps for the lower and upper half of your main speakers. You have it correctly setup the way you have it now!!
audiorusty177,

That is exactly how I have my system currently configured. Preamp Outs to Subwoofer In and Subwoofer Outs to the amplifier itself. That engages the hi pass filter and gives me some control options on the subwoofer but are you also saying the system is now bi-AMPED  not just bi-wired? I'm just trying to make sure I understand here.

Thanks!
My apologies I should have given a bit more info. The subwoofer is a Sunfire SDS-12 so I do have the connections and controls on it to as I wish. Meaning I have the preamp outs run into the subwoofer in, followed by connecting the subwoofer outs to the speaker. As I understand it, I am automatically using the subwoofer's hi pass filter this way.

But I don't see a way to run the cables this way, through the subwoofer then back out, that would also include a bi-wire option, right? 

I mean, I'm pretty sure I am correct there. Run the speaker cables in a standard bi-wire configuration or run it through the subwoofer with bi-wire. I've looked over the Net for potential connection diagrams for a bi-wired system that includes a subwoofer in the path but I haven't seen any which makes me suspect it's enormously complex or can't be done.

Right?

j
My front speakers amps are connected with XLR-type analog connections from my preamp. The sub is connected to the extra RCA-type L and R analog outputs from the same preamp.

The front cabinet's roll-off in the mid-30Hz range. A SVS Ultra sub is set-up to play from 31Hz and below in the sealed mode. This minimizes any frequency overlap between the SVS Sub and 15 inch bass drivers in the front cabinets. 

Subs like REL’s mentioned earlier do sound great connected to the high-level speaker leads because they share the amplifier's sound character with the front stereo speakers.     
With a powered sub you are actually running a bi-amped system, which in my opinion is better than bi-wiring. If your sub does have a high pass filter (IME most do not) I would do as you have already stated, connect the preamps outs to the sub and then connect the subs high pass outputs to your main speakers amp. 
Post removed 
I am not sure I understand. If I do, then this is the answer.

Subwoofers are powered… so you run a line from the preamp to the subwoofer. You do not want to connect speaker wires to the subwoofer.

If you do not have enough preamp outputs you can use a splitter at the preamp.