"Official" Audyssey thread (FAQ in post #1) - Page 1087

And after i run Audyssey my speakers are all in the -4.5 to -9db range, is it ok if i boost the level equaly on all my channels? so that i wont have to turn my MV up to infinity to get some sound from my system.

No, leave them as Audyssey detects them. that way Dynamic EQ will work as intended. it's only a few degress rotation of the volume knob anyway.

As long as you increase all of them equally, it is ok and Dynamic EQ will
work as intended.
One thing it changes is when (where?) you have Reference Volume.
If you increase all speakers by 3dB, you will have Reference Volume
when the master volume dial is at -3 instead 0.

Hi Truls,

On most subwoofers when the LFE input to the sub is used the internal filter (in the sub) is ignored. Not familiar with your sub, better to check the Manual.

thats a good question mogorf, there wasnt any manual, but i can look/ask in the elemental designs forum.

Truls, is Friggin' Norway the cold part of Norway?

If your speakers are set to small with crossover at 80hz, then the only signal that would exceed 80hz at the sub would be the LFE. The LFE channel in most schemes is limited to 120hz max but in reality almost all LFE content is below 100hz.

Set the crossover on your sub to 100hz...set the crossover for the sub in the receiver at 100 hz and set the front speakers to 80hz.

To complicate things, some processors actually send LFE signals above the crossover setting of the sub to the fronts. Not sure how the Integra does it. If it's truly an LPF, then you do risk losing between 100 and 120hz of the LFE, but in reality, you will be losing almost nothing.

Greetings

Is the Audyssey MultEQ better than the Pioneer MCACC?
If the recievers matter the ones Im thinking of is the Denon avr-1611/1911
and the Pioneer vsx-920/1020.

Yes pepar, its the cold part((

Wel, i got my crossovers fairly acurate now. Guess the LFE input on the woofer bypass the LPF, if i adjust the LPF all the way down to 40hz the sub stil sounds the same.

Im crossing the LCR at 70hz now, and audyssey adjusted the LPF to LFE to 120hz. Guess thats ok. IMO 70Hz sound way better on music than 80Hz, but on movies it's not audiable to me, so w/e. =)

Any takes on MultiEQ XT vs MultiEQ XT32? Is it worth a reciver upgrade?

Hi,
The LPF of the LFE is not a crossover. It has nothing to do with the bass from the satellite speakers. It is only a lowpass filter that is applied to the separate LFE track found in 5.1 content. That track is authored to have content up to 120 Hz so any other setting would be wrong. In fact, it's wrong to even have this as a setting that the consumer can change in AVRs. But, that's another story...

It is the speaker crossover settings that determine what bass content from those channels will be sent to the sub.

Aaah, so nomather if i adjust the LPF to LFE down to its minimum the sub would stil play up to the spekares crossover when it comes to music and "not-LFE content"

Then it stays on 120Hz. Had the impression that it was the LPF to the sub in general. Tnx for the heads up=)

Hi Truls, I still feel a bit of uncertainness in your words as regards the captioned subject. No problem, meanwhile here's an excellent guide to Bass Management: http://forum.blu-ray.com/subwoofers/...anagement.html Its a good read.

I've read it a thousand times.

At least one manufacturer "claims" that the sub LPF is actually a true crossover and anything above the LPF setting is routed back to the fronts....Emotiva. I don't actually believe that statement, but that's what their CTO claims in their site forum (unless he's changed it).

I haven't seen the exact wording of that. It could be that they are referring to the speaker level connections on subwoofers. If you run your speaker wires through the sub then there may be an actual crossover in the sub. Those connections along with the quaint filter controls on subwoofers are there for people with legacy gear (typically analog 2-ch) that don't have any other way of generating a true subwoofer signal. Modern AVRs with digital bass management do this job correctly and so these controls just get in the way...

However, it's simply not possible to have a crossover with an LPF filter. A crossover requires the combination of an LPF and an HPF filter working in unison. Furthermore, the slope of these filters has to be 24 dB/octave and 12 dB/octave respectively in order for the complex amplitude and phase summation to work correctly at the crossover frequency. The analog filters found in most subwoofers typically don't have the proper slopes.

Leaving aside pure LFE, what's the matter w/that claim?

A XO is a LPF and HPF filter dividing the spectrum at a certain freq.

24 dB/octave LP and 12 dB/octave HP filters only work with sealed main speakers that roll off at 12 dB/octave near 80 Hz (crossover frequency). If your speakers are different than that THX standard (2nd order acoustic rolloff near 80 Hz), then the slopes do not match your speakers anyhow.

My larger sealed main speakers roll off at 12 dB/octave near 45 Hz, and I blend them with the subwoofer with use of the subwoofers 12 dB/octave analog LP filter set to 50 Hz. 12 dB/octave LP plus 12 dB/octave acoustic HP is 1/2 of an electronic crossover (electronic LP filter only).

System setup that way sounds better than the system does via the receiver's electronic crossover!

It need not be 100% electronic!

A bit of history might be useful.

The 120 Hz LPF was included in DD encoders, not to enable 120 Hz LFE effects to be delivered, but to prevent higher frequencies from aliasing, since the LFE channel includes no transform coefficients above a certain point--thus saving bitrate. It was standard recommendation and practice to apply an audio LPF upstream to define the bandwidth of the LFE signal. This filter was typically at 80 Hz in movie production, as that was the maximum bandwidth of the DTS Digital film system's LFE channel. DTS consumer decoders (lossy) have a 90 Hz LPF in the LFE channel.


You do not like the Linkwitz-Riley filters Tom adopted for THX? The LR4 alignment sums to flat (24 dB HP and LP). THX uses a 12 dB electrical HP in series with a 12 dB acoustic response in the satellite to achieve the overall 4th-order response.

I was just wondering...if a audyssey in receiver cuts the speakers in range from lets say -9 to -6 db does that mean that the receiver has at 0 db (reference level) more power reserves than a receiver that would cut the speakers in range from -3 to -1 or +1 to +3 or that is the same? Will the receiver that will cut speakers at higher levels play cleaner and better at 0 db and will not be cliping? I just wonder what you guys think?
Thanks

So I got this I my inbox today from Audyssey. Are the SoM docks really in Apple Stores as of today or just coming soon? Thanks!

Jeff

You cannot draw any conclusion like this between unlike electronics. The AVR may have a different gain structure, or the power amps might have different gains. But for a given AVR driving two sets of speakers with different sensitivities, the setup with the lower gain offsets will indeed have that many dB more amplifier headroom on tap. Whether the more efficient speakers can deal with it is another matter.

Confused... That's exactly what I was talking about. I was simply describing the electrical characteristics of the filters. One obviously needs the same slope on both sides in order to sum correctly. The satellite speaker gets half the slope electrically and the other half acoustically.

Ok. Just that you had not mentioned anything about the speaker's role in this. And since many (most) speakers in common use with Audyssey are not designed to meet the THX 80 Hz rolloff requirement, nor adhere to a 2nd-order Butterworth alignment regardless of the rolloff point, the 4th-order high pass needs to be done electrically most of the time. Does the HP filter in AVRs offer the end user a choice, or does the AVR automatically select the correct order based on what it measures? I guess these filters are outside the scope of Audyssey, but you might know how that's handled.

Just to be clear: LR4 has nothing to do with 80 Hz, it can be applied at any frequency. It simply says that one needs two cascaded 2nd order Butterworth filters on either side (highpass and lowpass). These can be all electrical or a combination of acoustical and electrical.

All AVRs that I know of use this filtering scheme for bass management.

Ideally, one would measure the actual slope of the speaker's acoustical roll off and apply an electrical highpass with the appropriate slope to make sure that the complex (magnitude and phase) summation with the lowpass is correct. But, that's not (yet...) done in AVRs.

Roger, you're up.

I'm running two subs' with my Onkyo with Audyssey using a MultEQ setup and find it provides a bit more of "fill" to the room (a very nice - yet a subtle change over just one sub..) - ...So my questions is... Is that what's to be expected..(just a bit more fill..?) - and are there any tips on calibrating two subs' - versus just one.(i.e. - do I turn off one sub to get an accurate 75db, and then do the other in the same fashion..?)...

Any tips to dial this in the best way possible would be very appreciated..

Thanks!

Phil

How will XT32 handle subs with different rolloff?

My situation:

I have two large true subwoofers that is conencted to my existing receiver for LFE and below 40hz duty. My LCRs have a 15" midbass (40-200) and Klipsch KL-650 for the rest. I use the Behringer DCX2496 for that 200Hz XO.
I'm getting my Onkyo PR-SC5508 in a few days, but my DCX is out of commission for at least another few weeks (service). So I plan to run the subwoofers on one subwoofer output and the three midbassmodules on the other. Will XT32 handle that? I realize that XT32 will try to push my midbassmodules below 40hz, I'll just have to be careful not to runout of excursion for a few weeks. But my main subs go down to 11-12hz.
Is there even a point trying? i can just cut the midbass modules from the system for a while, but was wondering if XT32 will account for very different capabilities on the two sub outputs?

I'm fairly sure this has been covered, but with 800 pages, searching did not seem to get me far.


nvm...

We received official confirmation today from Onkyo that the PR-SC5508 will indeed be MultEQ Pro ready. Apparently there was confusion with their customer support because the 5507 did not have this feature last year...