LFE means Low Frequency Effects. When a bomb explodes in your favourite video you don't need your sofa to be shaken in stereo. In fact mono is much more efficient then.

In music productions bass can be left, right, on both in phase (mono) or with a delay or phase difference between left and right. This is very seldom the case for various reasons: it won't survive a vinyl manufacturing process, home theater systems with one sub (WAF guaranteed) are found everywhere to also play music (so mastering engineers have to adjust), and the room situation usually makes it impossible to efficiently play and hear such a signal so that it sounds like with a good headphone (which indeed is the final solution to hear such sub-vibrations perfectly without any room trouble, even in stereo).

After over 25 years of experience with dozens of subwoofer setups I can not agree.
It is not seldom and occurs in many classical and jazz productions and other recordings (Yello). It is clearly audible even in less perfect room situations. WAF is certainly no concern of mastering engineers or producers.

So many assumptions, clearly not based on personal experience.

But why should I bother, nobody cares.

Good call Curt.

It's good when the police turn up..

O.K....done this morning.  Above is both speakers, 1/6 octave smoothing.  Speakers have a built-in treble boost adjustment which I put on its maximum position on both speakers.  No eq.

Also, here is composite graph showing both (black), left (brown), and right (red).

Rick,

Let's conduct a Mad Science experiment here...

Moving with the deftness of an Audio Ninja...I'd ask that you move one of the Speakers fore or aft, 1 foot.    Strictly in the name of Science!

Run a Sweep of that modded position.  I want to see that 200hz null change...we haven't a hope on Earth of EQing that.  You can't eq nulls, and 200hz is murder on a nicely recorded Vocal that we both enjoy.

Tell your Wife in advance that I apologize. 

Trying to Win One for ya Pal.

It seems you've made considerable strides at 50hz, and 200hz.   This HF droop business is a puzzler.   Where's McGyver when you need him? 

Have the Grand Kids been playing with the Treble encoder, or has Rick cleverly crafted a Lo-Pass Filter in B5 of the EQ? 

Not to run you around in circles,.but perhaps you can take a Near Field Measurement of one of the Speakers.  Center the Mic directly in front of the Speaker, at a 1M distance.   Let's see if the HF roll off remains.   

Curt

Sure!  The Treble encoder would offer some relief.   The question of WHY we see the droopy HF response remains.    The Near Field test might offer clues.   If we then STILL see the roll off....hmmmmm

Curt

While you're there, you might aswel take a measurement of all drivers.
Just make sure you're using the correct zero degree calibration file for nearfeild measuring.

Hi Willem.

Sorry, I was referring to RP and his current speaker measurements.

Are you happy with your set up now or do you feel you still need to tweak?

Glad you're happy but it's a game we're in where you can never truly be 100% happy.
I bet there's guys n gals out there with million dollar systems that sometimes think... Could I make this sound better!

I hope RP will get to grips with his system and measurement techniques to better his results and listening pleasure....

Test done and interesting results.  The on-axis, tweeter height measurements don't seem to exhibit that HF "droop" after about 3kz in either speaker.  Graph shows each speaker measured at a distance of 36".

I find these measurements really interesting as it proves the effect of low frequencies within a small room.
The way I read this is the red measurement is indicative of a speaker very close to a room boundary and the black is a touch further out from a boundary.

Like you Willem, I do not EQ above 400-500hz as I feel you're killing the sonic signature of the speaker within the particular room.

Thanks for all the comments!  As it's probably abundantly clear, the space where I have my system and listen to music was not designed by an acoustical engineer.  With the help of Curt (big shoutout to him!!) and everyone here who participated I think that, referring back to post #312 and, in light of the near field measurements showing that the speakers, themselves, are performing as expected, I may well have gone as far as possible within the room's limitations, what I can do with the ADI-2 Dac's eq functionality and my own (very substantial) technical limitations.  I'll probably fiddle with the tone controls a bit, but a quick listen to a few of my go-to tracks indicate---at least with my older ears---I may be, in fact, hearing all of the treble I can. And, the bass sounds pretty awesome, too.  Amongst others, I use the last few minutes of the "Saturn" track of Holst's, The Planets (Dutoit/Montreal), which has a wonderfully low organ pedal note, to gauge how my bass is doing.

I have to say, this has been a fascinating process and I do believe that the overall sound has been noticeably improved.  I do also have to say that I'm so impressed that, within just an ordinary living space, it's possible to hear such astonishingly detailed and involving music.  Could more be done?  I'm quite sure of that, but I'm not nearly as sure that acoustic treatments, etc. in order to further what some might define as a little obsessive (in light of the terrific results already achieved), will be errr…..spousally tolerated.  Especially so in a space that gets constant use by family, for entertaining, etc.   So, now, back to your regularly scheduled programming ;>)...

In light of the graph in post 312, I would agree.  The "both" speaker measurements there suggest you're correct.

I think you could benefit from the possibility to equalize left and right channel separately. The red channel has a nasty peak at 30 Hz and the black channel has two, at 50 Hz and 90 Hz.
However, I am assuming this is with just the main speakers. What are you doing with the subwoofers?

Hi Rick.

Firstly I would like to apologise for not conversing with you more in your endeavours but I truly felt that, due to my inexperience in all things acoustic, I felt I would only muddy the waters even further for you which would've only caused you frustration and confusion.

I'm incredibly excited for you. I know that feeling of being in control of what you hear and how you hear it and all it took was for you to spot a thread that peaked your interest.....:)

Just enjoy the music my friend. Don't bog yourself down in doubt about whether what you're hearing is sounding right BUT....do tinker every now and then just to satisfy that curiosity that we all have in us.
At the end of the day, you always have these settings you have now locked in so return to default if need be.

Thanks for sharing what you listen to to evaluate your hardware. You made me fire up my system just to hear those deep organs you mentioned in "Saturn" and by god it didn't disappoint!!
That is some seriously low end bass right there!
It gave me a chance to check what Curt had advised me to do with my 50hz high pass.
Without the EQ, bass was a tad boomy, with the EQ it was, to me, perfect.
Bass was retained and as far as I could tell, no loss of detail.

Please do share some more of your test tracks if you have time as I'm sure we, and many others will be interested!! I certainly am.

Anyway, I've rambled on a wee bit here but I just want to wish you all the best!

Don't be a stranger mate...

Mike.

Thanks for the kind words, Mike.  I don't listen to any "electronica", but I'm aware that it has some seriously deep, artificially generated, bass.  However, continuing the theme of low organ notes, you might also have a listen to the gorgeous 2nd movement (poco adagio) of Camille Saint Saens' 3rd symphony (aka the Organ Symphony).  Listen to the whole movement as the low notes are scattered throughout.  The version I have that has the most powerful organ sound is the remastered Living Stereo classic recording of the Boston Symphony conducted by Charles Munch.  I got it as a download from HD tracks....

You're welcome Rick.

I find other people's listening choices fascinating.
I would never have considered organ music but yet I love it
Very "earthy" in nature.

I might start a thread about people's listening habits yet..
HD Tracks you say...... I'll have to give that a look-see

Hi...

With some additional assistance from Curt, including a whack upside the head for attempting to eq- correct some nulls with boost, and investing a whole morning adjusting my sub's polarity, and crossover values, plus starting from scratch on all of the eq settings, along with the minor physical placement adjustments from previous days, this is what I've managed to accomplish:

I'm actually pretty pleased looking at just the FR measurements.  There's the null at about 223 hz, but that is the worst offender.  Absent any new brainstorms on what to do differently/better, I'll go back to listening for a few days and see how I like the actual sound of these revised settings.

The right speaker is what you're thinking about.  It's curved, but at the absolute front, it is 34 inches from the wall to its right.  I can widen the speakers out by a max of maybe two inches.  There is no room to narrow them and I have moved them forward as far as I'm "allowed" (that was the slight repositioning of a few days ago which did help) and moving backwards is not an option, either.  Measured separately, both speakers show the same notch.

Willem,

The graph posted in #339 includes both subs--everything eq'd.  For my particular room arrangement these REL-305 subs can only be connected via the speaker level input.  So, they're seeing the exact same signal as my speakers.  Of course, the subs have volume and crossover adjustment dials as well as a two-position polarity switch.  So, eq'ing via the ADI dac affects both speaker and sub output simultaneously.

Upon Curt's recommendation, I spent a lot of time this morning determining the subs' proper polarity and, even more importantly, adjusting the volume and crossovers in real time (looking at the live FR plot as I was twisting the knobs).

The ability to see the on-screen real-time effects in my measurement software of both the sub adjustments and, after I got the subs in order,  the appropriate EQ adjustments, got me to this point. 

As Curt says, this FR plot is now "respectable" which I consider, given my very difficult room, a good accomplishment.

As an aside, I'd attempted to follow the sub mfr.'s instructions on how to determine polarity by ear.  My ear-level blind test gave me a 5 to 4 (with one "no difference") preference for one switch position.  Can we say....that was not particularly definitive??   The measurement software clearly indicated that the opposite position was the correct one to use. A good lesson....

Hey Guys,

RP and I have burned the Midnight Oil over the past days..

What we have here...is a Situation where Speakers that can't be moved.  Nulls that cannot be EQd, and Room Treatments that cannot be employed.   What now?

Folks...BEFORE you invest THOUSANDS in Audio Gear, do be certain that you can use it to it's full advantage.

Curt

I just wanted to add that I increased the bass lift a bit more to get it closer to the ideal Harman curve, because I felt the sound was a bit too lean. This is on top of the dynamic loudness that I set some days ago (and pretty aggresively so, given the inefficiency of my main speakers and the large room size).

I am afraid this was a bit beyond me. Do I take it this is about reverberation and reflections at frequencies above the Schroeder frequency i.e. typically above 100-250 Hz, depending on room size? I have always understood these cannot be equalized and have to be addressed by absortive materials like rugs, bookcases etc. Is that right?