Do subs with speaker level connections high-pass the mains?

[KEW]

These are the subs that accept the L & R speaker cables then output the signal to go on to the speakers.
Do they pass the full signal on to the mains, or do they apply the crossover setting to the mains as well?
TIA!

 

[TheWarrior]

These are the subs that accept the L & R speaker cables then output the signal to go on to the speakers.
Do they pass the full signal on to the mains, or do they apply the crossover setting to the mains as well?
TIA!

No, you have a selectable crossover which passes all frequencies above to the speakers. This was the old method of bass management.

 

[TheWarrior]

Actually, that was two different questions: Title - Yes, speaker level connections are high pass in this situation, because you are high passing the subwoofer

 

[j_garcia]

That high pass is also FIXED. Only the sub is affected by the sub's x-over dial; it does not adjust what is passed to the mains.

 

[Steve81]

Do they pass the full signal on to the mains, or do they apply the crossover setting to the mains as well?

I expect most are just passing the full signal to the mains, with the expectation that the end user will utilize the low pass knob on the sub to achieve a good blend. To high pass the speaker level outputs, the plate amp would need to include passive XO components, something like this, just for a simple fixed filter.

 

[KEW]

Thanks, I had always assumed that, but then I started wondering why the sub control is labeled "Crossover frequency" instead of "roll-off (or low pass) frequency".

 

[Pogre]

I have always wondered about this!

 

[TheWarrior]

I think the main point here is to read the instruction manual of the specific subwoofer being used as to what signal it will send to the speakers, as that seems to differ by manufacturer.

 

[everettT]

Most of the ones I've had experience with have fixed HP, including velodyne, focal, and monitor audio.

 

[Johnny2Bad]

The high level connection (speaker level) at your sub is in essence a parallel connection. One (to your speakers) incorporates a high pass filter, like a speaker crossover.

The other ... the signal that the sub uses, will pass through a transformer that changes it to a line level signal, which is then used by the sub just as if it were line level (RCA) input from a preamp. All the signal processing the sub performs is the same whether it's a line level input or a speaker level input.

 

[KEW]

Most of the ones I've had experience with have fixed HP, including velodyne, focal, and monitor audio.

Were these mostly pro audio or consumer audio?

 

[Steve81]

Are you looking at anything specific Kurt, or just curious?

 

[lovinthehd]

I've always assumed the "crossover" label instead of "low pass filter" on many subs that lack the high pass filter is simply due to marketing department thinking that many have heard of crossover but have no idea what a low pass filter is. Not too many subs have the high pass filter built in, and I've seen some that only offer it on low level input/outputs rather than on high level inputs/outputs.

 

[KEW]

Are you looking at anything specific Kurt, or just curious?

It is the current deal on the JBL Studio 550p ($189 each - I just posted in the deals section) that got me wondering. If they high passed the mains, I could see using them in systems without AVR bass management. That would add a lot to their value!

I don't see any specific information on them, and there is also the added confusion of the manual I downloaded which does not even have the speaker level inputs in the diagram or specs. Actually it is not mentioned in the specs even on the JBL page that does show the speaker level connections!

Right now, I would guess they decided to add these connections, but did not update the literature. So, I guess I need to assume no high-pass for mains unless some new info come to light.

 

[lovinthehd]

The 550p manual says:
"Crossover control: This control determines the highest frequency
at which the subwoofer reproduces sounds. The higher you set the
Crossover control, the higher in frequency the subwoofer will operate and
the more its bass will "overlap" that of the system's other speakers. This
adjustment helps achieve a smooth transition of bass frequencies between
the subwoofer and the other speakers for a variety of different rooms and
subwoofer locations. NOTe: The Crossover control functions only when
the Input Mode switch is in the "Normal" position. When the switch is in
the "LFE" position the subwoofer's built-in crossover and Crossover control
are bypassed."

Sure doesn't sound like it has any high pass filter option what with the overlap mentioned....

 

[shadyJ]

I have never heard of a sub that will high-pass a speaker-level connection. That would be a very expensive addition to be able to do that.

 

[lovinthehd]

I have never heard of a sub that will high-pass a speaker-level connection. That would be a very expensive addition to be able to do that.

I have but couldn't think of any examples so a simple search brings up this manual page indicating such....

 

[Steve81]

I have never heard of a sub that will high-pass a speaker-level connection. That would be a very expensive addition to be able to do that.

I have but couldn't think of any examples so a simple search brings up this manual page indicating such....

FWIW, just browsing around I also found one that "definitively" has a high pass filter on the speaker level outputs:
Def Tech ProSub 1000 Manual

The integrated electronic crossover incorporates high level inputs and outputs as well as a low level input, precise equalization, continuously variable low pass filter (between 40 and 150 Hz), fixed speaker level high pass filter (to match the ProMonitors) and a precision volume control

 

[shadyJ]

High-level transmission is not the place anyone should be filtering a signal. That is crazy. It is essentially adding an unexpected element to the speaker's crossover. I have to wonder what it is doing to the impedance of the circuit and how that is affecting the speaker's behavior...

 

[Steve81]

It is the current deal on the JBL Studio 550p ($189 each - I just posted in the deals section) that got me wondering.

That's not a bad price. Heck, for under 2 bills, I'd consider buying one for my second rig... Then again, I'm not really interested in telling my wife "hey, you know what I could really use right now is another sub"