jubilee

[bhendrix]

Xover 2

[bhendrix]

You want the HiQNET System Architect software.

Here is link:

http://hiqnet.harmanpro.com/sa_download.php

[DrWho]

Here's all the images in a single zip file.

XTi_Settings.zip

[Chris A]

Interesting EQ curves and crossover freq. Thank you very much Bill and Mike. I have updated the Crown settings to match your supplied settings. I assume these are the EQ curves that were generated in the anechoic chamber environment (as alluded to in Roy's separate email). My previous settings were 800 hz gentle slope and RTA/calibrated mike in the sweet spot. The difference is really quite large, I must admit. Even so (and it is early in the AM here to be cranking it up for a "hand volume" listening test), the sound is still amazing if perhaps less forward now with these new settings.

Now the new kid on the block asks stupid questions:

1) How do you reconcile EQing your speakers in a real listening environment relative to using anechoic corrections? Do you use an automated RTA/EQ, just stoically set them flat to anechoic and leave them, try to shape the EQ by ear, or some specific combination of the above techniques? Do you personally vary your EQ based on source material? If so, generally how do you do it?

2) With the really excellent directivity of the Jubs at freqs above the bass region, how much and where would you apply room treatment (diffusers and traps) as a first cut? Have you considered the ceiling near field relative to the listening sweet spot. How far back is your sweet spot? I realize these questions are specific to those who've had their hands on Jubs but the answers really don't have to be limited to just Jubs. Any pi (wall/floor mounted) or pi/2 (corner-mounted) speaker probably has similar characteristics.

Chris

[Chris A]

Wow, I think that I take back question #1. I turned them up this morning... Wow.

[mikebse2a3]

1) How do you reconcile EQing your speakers in a real listening environment relative to using anechoic corrections? Do you use an automated RTA/EQ, just stoically set them flat to anechoic and leave them, try to shape the EQ by ear, or some specific combination of the above techniques? Do you personally vary your EQ based on source material? If so, generally how do you do it?

Hey Chris

You've actually asked pretty complicated questions which are really system/room specific to a large degree.

I also want to add that the EV DX38 and the Crown Xti settings supplied by Roy are not only optimized in the anechoic chamber but also evaluated in a room meant to be somewhat typical of a home listening enviroment with Roy also using some reference recordings that he has used for many years.

Proper room measurements and room treatments ( using absorption, diffusion and some form of modal control would be the best approach versus EQing ). My experience has been that unbalanced absorption is often detrimental to good sound and most rooms would actually benefit from methods dealing with the modal region of the room and proper use of diffusion.

With the above being said I have also used the Behringer DEQ2496 with limited succes in the past with Khorns and Jubs(even though I currently have it in bypass for most of my listening). I have one specific listening location that I optimize my settings for and was to a limited degree able to deal with a problem room mode. The main thing to remember is if you EQ for one location you must check other listening locations to see if the changes are acceptable there also since those locations will be altered also. Whenever I have used the Behringer auto-setup I always take their suggestion and exempt the below 100Hz bands and I also exempt the above 5KHz bands also in preference of setting these by ear/measurements. I also never boost in the modal region and limit any other adjustments to generally at most +/-6db and mostly +/-3db. Of course even though I do take measurements (ETF type mostly) I use my ears as the final judgement.

When it comes to EQing for source material that obviously needs help I have created a few curves similar to what tone controls would do and saved them into a few Memory Settings of the Behringer for quick access.

2) With the really excellent directivity of the Jubs at freqs above the bass region, how much and where would you apply room treatment (diffusers and traps) as a first cut? Have you considered the ceiling near field relative to the listening sweet spot. How far back is your sweet spot? I realize these questions are specific to those who've had their hands on Jubs but the answers really don't have to be limited to just Jubs. Any pi (wall/floor mounted) or pi/2 (corner-mounted) speaker probably has similar characteristics.

The Jubs actually come together pretty quickly and so your sweet spot is actually more a function of the room's dimensions and modal response.

As far as ceiling treatment I do have some absorption panels at the first reflection points but to be honest these are left over from when I used Khorns and I've not really investigated whether these are of any benefit with the Jubs but I will as time permits.

I also intend to explore modal control methods in the future with my goal being to clean up this frequency region (without EQ) which I have come to believe is my weakest link in my system at this point other than room size issues.

I have actually had the best success in my own room using diffusers(RPG Skyline which by design supresses the specular reflection) at the first reflection points versus absorption ( I really try to avoid absorption if possible in favor of diffusion whenever possible because it just sounds more natural and maintains the tonal balance of my room/system IMO anyway).

mike tn[]

[bhendrix]

Hi Chris,

The EQ curves for the XTi were set by Roy in the chamber. I believe the best way to play the speakers is with the EQ set per Roy's formula. Any challenges with the room should be address be diffusion/dispersion rather than EQ.

The 402's control dispersion much better than other horns so there's not much spilling out and bouncing off the floor and ceiling.

These "big uglies" make fabulous low-level, near-field monitors. If you sit fairly close and on-axis, the imaging is incredible. As you apparently discovered this morning, they are also quite capable when you toss a couple of watts in them.

Are you going to create and combo 2 channel / home theater setup with your jubs? If so, a JubScala (little ugly) makes a great center channel. I have a LaScala LF with the 402 on top, also calibrated in the chamber by Roy to match the Jubilees (big uglies), that is the perfect center channel.

[DrWho]

You still want us to go easy on ya? There's gobs and gobs of
theories on what constitutes good EQ practices - most of em seem to be
incomplete or make some bad assumptions, which often leads to a lot of
confusion. With that in mind, I'll just share what I've come to
understand, knowing that there is still more to learn. You might want
to grab a cup of coffee []

There are a few things happening and
I think it's best to look at each one individually. In the anechoic
chamber, we see exactly what the speaker does by itself. In the
listening room, you have the speaker-to-room interaction, which can be
divided into the direct sound and the reflected sound. The important
thing here is the direct sound is actually anechoic until the first
reflection arrives at the listening position. If the reflections takes
long enough to arrive, then we percieve it as a distinct and separate
reflection (echo). If it arrives early, our ears don't pick up on the
fact that it's a reflection so we percieve it as part of the direct
sound. It of course doesn't sound like the direct sound though....it's
a smeared version of the direct sound.

An RTA doesn't make any distinction between early and late
arriving reflections. In fact, you could think of an RTA as lumping all
of the time-smear into a single measurement as if everything arrived at
the same time. Normally this would look very chaotic, but that's why
they add a 1/3 octave smoothing to them (to help correlate the visual
representation to correlate to about what we would hear).

The
problem with EQ is that it doesn't change the fact that the sound is
still bouncing off the walls in your room. In other words, it doesn't
fix the time-smear, which is where the increase in clarity needs to
happen. You will, however, see dips and peaks in the frequency response
that are caused by the reflections.

The other problem with EQ
is that you need to match the Q of the problem, which is rather
ambiguous when using an RTA. Just to illustrate that fact, here's an
example of a raw measurement with no smoothing:

Here's the same measurement with 1/3 octave smoothing:

And there here's the measurement with 1/3 octave smoothing and EQ applied:



(doesn't that look a lot flatter there in the middle?) []

But here's the measurement without smoothing and EQ applied:

Notice how the EQ at marker 2 looks better, but 1, 3, and 4
aren't? Ultimately this can come down to the fact that 1,3,4 are not
minimum phase, but 2 is. The reason the EQ at 2 works is because that
is part of the raw response of the driver. The craziness at 1,3,4 is
due to a reflection with the floor. Normally you see a lot more
craziness in the high frequencies, but I was using some foam during
this measurement to reduce the effects of reflections in the room. In
other words, I tried to minimize the effects of reflections to provide
a simpler example! It only gets worse than this. If we looked at the
response in an anechoic chamber (I don't have one so can't do an actual
measurement), we wouldn't seen any peaks or dips at 1,3,4, but we would
still see the peak at 2.

Since 1,3,4 are the result of
reflections in the room, moving the mic as little as an inch is going
to dramatically change their location and magnitude. I did not perform
any measurements to demonstrate this so you'll have to take my word on
it. When I get back to campus I can show some unsmoothed plots where
the microphone moves if anyone is interested. Anyways, my point in
showing these pictures is to illustrate that the frequency response is
crazy insane....when measured in a room.

In the anechoic chamber
things look a lot more like the smoothed plot, except that no smoothing
is applied. The most obvious EQ being used on the Jubilee is the shelf
filter bring up the falling response of the tweeter. Because the K402
is a constant-directivity horn, the HF output is going to drop
6dB/octave...this is actually expected behavior and in a way a good
thing, but got a bad wrap during its early inception because early CD
horns were using diffraction slots (yuck) and they weren't very good at
providing a constant directivity either (so no real gains). Without the
"CD EQ" (compensation for the falling response of
constant-directivity), you probably had the tweeter turned up louder so
that you could hear the highs, which in turn would make the mids too
loud (thus sounding "forward").

If you go a step further, one
could think of using EQ to correct the power response of the
speaker...then, if you put the speaker in the room, you can guarantee
that the direct sound and reflected sound share the same tonal balance.
Without a flat power response, the reflected sound is going to have
different frequency content than the direct sound. If you put a flat
power response speaker in your room, and then treated all the early
reflections so that every reflection at the listening position was
outside the Haas window, then you don't end up with any time-smearing
and all of the reflections sound as if they are supposed to be there.
In fact, listening in an anechoic chamber doesn't sound natural at all
(too dead)....we need the reverberation of the room, but we need to
make sure the reverberation doesn't reduce intelligibility - which is
achieved by getting rid of early reflections.

The other consideration though is that homes are too small to
achieve true reverberation. In other words, there aren't enough
surfaces and the room isn't large enough to create a true reverberant
field. Because of this, reflections should only be absorbed when
absolutely necessary. In other words, they should be diffracted so as
to breakup specular reflections into multiple smaller reflections
spread out over time. Here's an article that provides some pictures of
an ETC with good labels:

http://www.rpginc.com/cgi-bin/byteserver.pl/news/library/HT_AcD.pdf

And just in case you're interested, here's the ETC for my measurements above (notice the floor bounce at 6.88ms):

The lack of reverberant field in my measurement is mostly the result
of my putting acoustic absorbtion behind the microphone because this
was part of a series of measurements of dialing in my Chorus II's with
an active crossover and I wanted to get as anechoic as possible.

Ok, I dunno if you wanted to know any of this crap from above, but
there it is for you to spend as much time on as you want, lol. To
answer some of your questions. I always use EQ for the anechoic
response of the speaker. Any frequency response abberations resulting
from the speaker-to-room interaction should be addressed with
acoustical treatment because EQ doesn't fix the time-smear that results
from early reflections. I do not EQ my source material either (or
change EQ based on source material). The nice thing about the Jubs is
they have extremely controlled polars, in fact, so controlled that you
wouldn't need to address early reflections for the right speaker on the
right wall. In other words, the first early reflection from the right
speaker is going to be on the left wall...(vice versa for the left
speaker). I believe Roy has mentioned that the Jubs keep the sound off
the floor (which means its gonna be kept off the ceiling too). The
easiest way to tell would be to just measure the room. If you're
interested in measuring, I've started putting together a website where
I hope to detail everything I've been learning (and correcting my own
misconceptions as I learn about them too):

http://measuresound.googlepages.com/

I mention it because I have only spent $100 on my measurement rig and it can do some rather powerful things.

I don't mean to drop a bomb of a post like this, but you did
ask...and it's winter break so I've got plenty of time on my hands []

[mikebse2a3]

Excellent Post Mike! Thanks for taking the time to explain all that.

I do not EQ my source material either (or change EQ based on source material).

I must say personelly I have no problem taking an obviously poor recording that responds to some reasonable EQing and making it more listenable/realistic.

mike tn[]

[DrWho]

I must say personelly I have no problem taking an obviously poor recording that responds to some reasonable EQing and making it more listenable/realistic.

Nothing wrong with that! I've just found that I would rather just listen to the music than try to tweak the music.

I've also got this stupid idea about preserving the art of the sound engineer (no matter how bad I think the engineer was) - much like I wouldn't paint a mustache on the Mona Lisa, even though I think it would make it far far more interesting. [A] It's just a different kind of listening (certainly not better), but it's why I don't bother with fixing the mix. I guess you could say that when I'm listening for enjoyment, I bust out the cheaper speakers that make everything palleteable...no need for hi-fi when you've got good music.

[Chris A]

I appreciate your directness in answering those two stupid questions of mine. Thanks Bill, Mike B. and Mike TN. These are real questions for me--and maybe for others.

Mike B.: when you get more material on your website (URL?) I'd like to keep reading whatever you find in this area and on related acoustics and sound reproduction issues. Because the Jubs apparently have such good controlled directivity and coverage within their zones, I just don't know about room treatments. Your experience is in fact very valuable.

Bill - I am going to use these in at least a 4.0 HT system; the preamp on its way is 7.1, but any future surround/center channels probably need to be small enough to fit in the "WAF envelope". My surround speakers are currently semi-large bookshelfs that I had. I don't know where I would put the Jubscala, but I would be interested in hearing more and seeing a picture of them. Heck, who knows, maybe its possible to change venues in my hacienda (or potentially change haciendas in the far term).

Mike TN: Sounds like you have been doing the room treatment thing for a while. I'd be interested in any insights you have with moving your panels around. I'd also like to have an idea of your relative room dimensions so I can understand if your setup is applicable to mine.

To all readers: Merry Christmas and Peace to You. I hope our troops can redeploy home soon from CENTCOM theater deployment. We need all those good people alive and healthy for the future of this country.

Regards,

Chris A.

[Chris A]

My wife just said that she really likes these speakers...even though they're ugly. She says that they're easy on the ears (She's singing along right now.)

She also asked if there is a Klipsch widows forum since I told her that "...statistically, between 81-98% of audiophiles are male". I told her I'd look for that forum.

[Coytee]

Chris...first, congrats!!

Second... just introduce her to Christy... hmm... maybe on second thought we don't need a contingent of women here "monitoring" us guys, doing our thing? We already got Amy (and she's pretty cool).... then Christy (she's pretty cool too)... hmm... JC's wife has chimed in... (also pretty cool) maybe there is a pattern there?

Ya...I say bring her on!

[Y]

[Chris A]

Mike B: I've just now taken the time to munch on your EQ vs. room acoustics reply.

1) I don't mind anyone being rough in their responses as long as it isn't ad hominem/childish stuff. My wife reads some of these posts, and I didn't want to turn her off after the first posting on the Jubs. Roy recommended that I go the forums, which I happily obliged.

2) Some of your reply addresses Haas effects (for others on the forum, this is the loudness-integrating effect of the human ear and the selection of the direction of the first arrival for multiple-source delays of less than 50 ms). Everything else connects the dots on my understanding of the physics of matter. Have you ever wondered if the RTA/EQs are doing some sort of cross correlation on the input pseudo-random noise generator as reference? That would change our understanding of the behavior of RTA/EQs if true. I look at how the unit sequentially adjusts the bands and wonder if the unit is doing something like this. This would preserve phase/time-of-arrival information. However, the RTA/EQ information from Behringer doesn't say enough to really understand what it is doing. RTA/EQs typically don't consider Fletcher-Munson, Haas, etc. effects because, first cut, machines don't integrate listening like humans do.

3) Both of my "stupid questions" I asked are actually connected to each other . I believe that your whole argument on room acoustics really points out that we must deal with early reflection and "mode" problems at their source.

4) Source material (i.e. CDs, SACDs, vinyl, whatever) mixing/EQ problems are horses of different colors, I think. These issues are hard-coded into our source bit streams/RIAA pathways, and I was wondering what the membership of this thead does about those problems. Generally speaking, I just don't listen to poorly mixed music for very long before I hit the eject button. This is a sad situation, really. If the problems are induced via "sound engineer signal processing" or mixing room acoustics issues then I believe we are basically out of luck.

[Coytee]

I believe that your whole argument on room acoustics really points out that we must deal with early reflection and "mode" problems at their source because EQ just rotates the early reflection problems to other parts of the room, and standing waves really wreak havoc on listening position selection.

I think (seriously) that you & MAS would probably enjoy a conversation. I realize you might not (yet) necessarily know who he is.

[Coytee]

yikes... what the heck happened here? spastick keyboard!

[Coytee]

too much coffee?

[Coytee]

Got me [:$]

[bodcaw boy]

I must say personelly I have no problem taking an obviously poor recording that responds to some reasonable EQing and making it more listenable/realistic.

Nothing wrong with that! I've just found that I would rather just listen to the music than try to tweak the music.

I've also got this stupid idea about preserving the art of the sound engineer (no matter how bad I think the engineer was) - much like I wouldn't paint a mustache on the Mona Lisa, even though I think it would make it far far more interesting. It's just a different kind of listening (certainly not better), but it's why I don't bother with fixing the mix. I guess you could say that when I'm listening for enjoyment, I bust out the cheaper speakers that make everything palleteable...no need for hi-fi when you've got good music.

i am not trying to tweak the music....i am trying to tweak the bonehead that did a bad job of recording the music. that is a big difference.....of course, i would be guessing what the music sounded like to begin with......

in Christ, because of God's grace,

roy

[Chris A]

I believe that your whole argument on room acoustics really points out that we must deal with early reflection and "mode" problems at their source because EQ just rotates the early reflection problems to other parts of the room, and standing waves really wreak havoc on listening position selection.

I think (seriously) that you & MAS would probably enjoy a conversation. I realize you might not (yet) necessarily know who he is.

Coytee,

I'll take that as a term of endearment. I've only seen a couple of posts from "MAS" but I can't say that I know that person.

What I really want is this: practical and effective solutions to problems that I've run into listening to sound reproduction systems.