Low pass cutoff for my speakers or full signal?

[paulwgraber]

Why do we not send a full signal to our front speakers or even surrounds if they can handle it?

My dirac sets basically everything at 70? Should I go with that even if my speakers are full bandwith?

Just wondering why we do this. Also Dirac set my sub to 120. I thought that was somewhat off.

Monoprice THX in walls. Onkyo RZ 50. RSL 12s sub

 

[lovinthehd]

Some do, there's even settings in avrs for it often (Onkyo calls it double bass IIRC). Some don't particularly want the lower range duplicated by the speakers and subs when the subs are generally more capable. Dirac sets a separate low pass filter for the sub than the speakers? Is that the infamous LPF of LFE type setting?

 

[TLS Guy]

Some do, there's even settings in avrs for it often (Onkyo calls it double bass IIRC). Some don't particularly want the lower range duplicated by the speakers and subs when the subs are generally more capable. Dirac sets a separate low pass filter for the sub than the speakers? Is that the infamous LPF of LFE type setting?

According to Gene, DIRAC does not let you send a full range signal to the bed layer speakers. So DIRAC would not work for me. Luckily I don't need, and have my own means to optimally voice the speakers to the space.

 

[William Lemmerhirt]

Well they’re not really full range. Show me where they are full range. That’s flat to 20 fyi.

Per monoprices own graph they start rolling off at about 100hz. From that, I’d say 70 is right on.

 

[TLS Guy]

Well they’re not really full range. Show me where they are full range. That’s flat to 20 fyi.

Per monoprices own graph they start rolling off at about 100hz. From that, I’d say 70 is right on.

Yes, from the monoprice graph F3 is somewhere between 70 and 65 Hz

Actually what I have found is that with in wall speakers, you have a lot of reflections from the wall, so it is quite chaotic from three speakers.

So actually I changed to crossovers 120 to 150, and let the in wall sub do the rest, so I only had one set of wall reflections to deal with.

In walls, as I found out are not a simple proposition. There are a lot of variables to wrestle with related to a way oversized front baffle.

 

[Oddball]

60-70hz F3 is not where you would need to bother with double bass or similar settings. At least if you can't get better response at least from some other bed channels, where you would do it for consistency/fill-in. Dirac seems to be doing a good job in that respect.

As far as 120hz sub crossover, that is what Dirac thinks is the best thing to do. Could experiment with setting this lower to 100hz if you feel that you need tighter bass. Also not sure if you could set the high pass filter on the sub (either at AVR or sub level) to roll off earlier or later, which would be another way to look at the crossover for the sub.

 

[William Lemmerhirt]

I think as HD mentioned, I think the 120 on the sub is the LPF of LFE.
It’s a low pass filter for the LFE channel, or the .1 that’s mixed into soundtracks. The .1 channel has content from 0-120hz and sometimes low passing it can help if you have localization issues. Otherwise common practice is to leave it at 120.

 

[Trebdp83]

People continue to confuse the LPF for LFE setting for a crossover concerning the other channels. The LFE channel has a 120Hz ceiling. So, setting the LPF for LFE lower than 120Hz can nip at the signal actually in the LFE channel. This is separate from the low range frequencies of other channels being redirected to the subwoofer based on their respective crossover points.

Even when using room correction, some may not like the resulting bass output from the system. If it seems too much, they can lower the crossover of the front channels a bit to lighten up sub output. If sub output seems too light, they can raise the front crossovers up a bit. This is why, when using APR/AVR processing, subwoofer gain and crossover settings are fixed with the crossover at MAX because signals from other channels can exceed the 120Hz ceiling of the LFE. Many aren’t crossing above 80Hz while many others may cross at 100Hz, 120Hz, 150Hz and so on.

Setting speakers to Full Band using an Onkyo means having to turn Double Bass ON to get a signal to the subwoofer when playing two channel signals and it results in some ugly behavior regarding multichannel signals. Those in wall speakers are not at all a Full Band speakers you want handling low frequency effects signals at high volume.

 

[Oddball]

By setting the LFE high pass lower than 120hz you are not actually doing anything that’s not appropriate. You are just rolling off the subs so that they don’t have noticeable rumple one octave above which would be 240hz. Each user should try how this impact their system and some people use so called cascading crossovers that start from 80hz. So there is really no best practice in this, will depend on your system.

 

[Paul McNeil]

Why do we not send a full signal to our front speakers or even surrounds if they can handle it?

My dirac sets basically everything at 70? Should I go with that even if my speakers are full bandwith?

Just wondering why we do this. Also Dirac set my sub to 120. I thought that was somewhat off.

Monoprice THX in walls. Onkyo RZ 50. RSL 12s sub

Dirac does it because the bass measures better and moreover there is likely less distortion, especially intermodulation, with the seemingly high crossover. Your amp (front left/right) may also be under less strain. And I'd guess Dirac has an easier time equalizing the bass with the fronts out of the picture down low.

 

[Oddball]

Dirac does it because the bass measures better and moreover there is likely less distortion, especially intermodulation, with the seemingly high crossover. Your amp (front left/right) may also be under less strain. And I'd guess Dirac has an easier time equalizing the bass with the fronts out of the picture down low.

Dirac does it because of now known bug that it does not do EQ below 20hz in complex setups. There is no theory behind it, just a fact that their product needs improvement.

Same what Gene already noted and what I experienced in ART demo. First run was with overall cut-off at 20hz (which is ART default) which sounded really thin. Next run was with below 20hz not being EQd which also did not sound great.

While they can sell tons of ART systems at this point of the hype they created, they will get a bit back-lash from the people with big systems if they don't roll it out with considerations to such systems. If I was them, I would release bookshelf version right away (with clear disclaimer what it does) and collect the cash and then worry about the big systems later on. Not that many of them anyway...

 

[William Lemmerhirt]

By setting the LFE high pass lower than 120hz you are not actually doing anything that’s not appropriate. You are just rolling off the subs so that they don’t have noticeable rumple one octave above which would be 240hz. Each user should try how this impact their system and some people use so called cascading crossovers that start from 80hz. So there is really no best practice in this, will depend on your system.

Except the Lpf isn’t a XO and isn’t related to the other speakers.

 

[Oddball]

I don’t think I ever implied anything differently. All I was saying is that some people roll it off before 120hz, if their systems call for that.

 

[Paul McNeil]

Dirac does it because of now known bug that it does not do EQ below 20hz in complex setups. There is no theory behind it, just a fact that their product needs improvement.

Same what Gene already noted and what I experienced in ART demo. First run was with overall cut-off at 20hz (which is ART default) which sounded really thin. Next run was with below 20hz not being EQd which also did not sound great.

While they can sell tons of ART systems at this point of the hype they created, they will get a bit back-lash from the people with big systems if they don't roll it out with considerations to such systems. If I was them, I would release bookshelf version right away (with clear disclaimer what it does) and collect the cash and then worry about the big systems later on. Not that many of them anyway...

Some out there are blessed with full range speakers but if they have adequate subs, and a flat frequency response, like me using Dirac correction, why try to run the fronts full range? As Erin (in his audio corner) has shown with many measurements, adding a cross-over reduces intermodulation distortion for just about any so-called full range, in the upper bass and even midrange region (basically the drivers doing those regions plus low bass). Why pull your boat with a Porsche if you have a (big ass) pickup truck?

I don't think the original post mentioned Dirac ART.

 

[Oddball]

Some out there are blessed with full range speakers but if they have adequate subs, and a flat frequency response, like me using Dirac correction, why try to run the fronts full range? As Erin (in his audio corner) has shown with many measurements, adding a cross-over reduces intermodulation distortion for just about any so-called full range, in the upper bass and even midrange region (basically the drivers doing those regions plus low bass). Why pull your boat with a Porsche if you have a (big ass) pickup truck?

I don't think the original post mentioned Dirac ART.

Not really sure what is Porsche vs truck but looks like you have it handled anyway Dirac ART is a wet dream that is supposed to ease all ur low end troubles and that is eagerly expected. What it deliverers is yet to be seen.

 

[lovinthehd]

I don’t think I ever implied anything differently. All I was saying is that some people roll it off before 120hz, if their systems call for that.

Well, you did say:

"As far as 120hz sub crossover, that is what Dirac thinks is the best thing to do. Could experiment with setting this lower to 100hz if you feel that you need tighter bass."[/QUOTE]

 

[William Lemmerhirt]

Well, you did say:

"As far as 120hz sub crossover, that is what Dirac thinks is the best thing to do. Could experiment with setting this lower to 100hz if you feel that you need tighter bass."

[/QUOTE]

Plus he added the thing about cascading crossovers.

For the record, I could have misunderstood him.

 

[lovinthehd]

Plus he added the thing about cascading crossovers.

For the record, I could have misunderstood him.
[/QUOTE]

Many get that language messed up with the LPF of LFE. It's just not a crossover.

 

[William Lemmerhirt]

Plus he added the thing about cascading crossovers.

For the record, I could have misunderstood him.

Many get that language messed up with the LPF of LFE. It's just not a crossover.[/QUOTE]

Exactly.
I think there may be some miscommunication, or misunderstanding. I’m not above saying it’s me.

 

[paulwgraber]

Outstanding info guys. I think im going to start with 70 for my speakers. Turn double base off. I have an rsl12s so might as well let it do its job right?