speaker placement for the neurotically precise - need tips.

[Thaddeus Smith]

as always, great tips and not toooooo much rabbit holing. BTW, my denon has the Audyssey MultiEQ XT.

[Rudy81]

My Integra has MuliEQ XT as well, but I'm fairly sure the basic pre/pro has different curves than the Denon. IIRC, the Denon does have a curve labeled 'flat'.

The AVSforum Audyssey thread is a wealth of information if you can wade through that super long thread.

[CECAA850]

speaking of which.. I found some old terminal cups from a pair of kg 3.5s I used to have. should be perfect and will get one shipped your way after Xmas.

What ga wire will it accept? Will it handle 500 watts?

shrug, at least 12ga for sure. I pulled the crossovers off, so it's just some gold plated knurled lugs that can accept either raw wire or banana plugs and whatever guage we want to solder on the back. just trying to be environmentally responsible and reuse when possible.

Should be fine then.

[Thaddeus Smith]

The AVSforum Audyssey thread is a wealth of information if you can wade through that super long thread.

thats the one thing i hate about that forum. ask a question, "go read such and such thread", wade through 4 years and 500 pages of posts only to have opinions change over time, follow a bunch of dead links, and wind up more confused than when you started.

[Rudy81]

I agree that the Audyssey thread on AVS has become rather large and not always user friendly. I did not mean to send anyone to go look for an answer per se. Just wanted to mention that most questions have been asked re: Audyssey on that thread and many technical answers provided by the designer. In my case, I found some useful information after skulking around in there.

[garyrc]

BTW, depending on which flavor of Audyssey is installed on your receiver or pre/pro, you do not always get a totally flat response. Audyssey can and at times does modify the HF response to meet certain pre-programmed criteria. The Pro version allows you to select what you get. Different pre/pro manufacturers use different curves and programming.

My understanding, which could be wrong, is that "AUDYSSEY FLAT"
would be the same on any pre/pro or receiver that offers it. The
results in the room are not perfectly flat, of course, and some
rooms/speakers/listening positions are more difficult than others. I
thought AUDYSSEY XT would be the same for all pre/pros & receivers,
but does not have the goal of making the room the response as flat as
the other position, but built in a rather sudden, somewhat narrow dip
near the top of the frequency spectrum, because of psychoacoustical data
the Audyssey people have regarding listening to MOVIES, specifically.
I used to have a copy of this curve, but can't find it anywhere ---
does anybody have it? The advantage of the Pro version is that you can
customize the response. Different manufacturers of receivers and
pre/pros do vary in their default positions for things like speaker
size, crossover, etc., which Chris at Audyssey suggests re-setting to
Audyssey's guidelines (e.g., if you have a halfway decent
sub, set the front R & L & C & surrounds to SMALL, even if
your fronts have marvelous low frequency response, because Audyssey has
many more automatic correction points available to the sub below 80 Hz
than are available to the deep bass regions of the front speakers.
Chris (of Audyssey) recommends NOT using the "copy" function that
many pre/pro/receivers have, then re-adjusting the EQ with virtual
sliders (often just octave sliders), because 1) The Audysssey room/spk
EQ will be lost the moment you move a slider, and 2) the EQ you come up
with may sound attractive in some ways, but will be "unknown" and not
nearly as accurate as Audyssey well set up.

For years, the movie
industry had two curves to which SMPTE recommended theaters and their
sound equipment be "tuned" to. The first curve can be ignored because
it was to deal with horrible optical soundtracks. The second was for
high quality magnetic soundtracks, and it drooped a little on the high
end, because they claimed that this curve at theater distances was more
closely matched to what relatively flat sound would sound like if a
speaker was a few feet away. All kinds of reasons were advanced in an
attempt to explain this, from the effect of reverberation at median
audience distance falsely suggesting to the EQ'r that the treble be
turned up to read flat (to make-up for reverberation containing
attenuated response at the highest frequencies, due to wall absorption
--- this problem can be dealt with today by building in arrival time as a
factor) to the interaction of ear structure and the downward angle at
which mid/high FQ sound would arrive at when passing from near the top
of the screen down to the main floor seats, to the secret preferences of
the engineers confronted with the average soundtrack, etc. etc. In
home size rooms, with Lps or CDs, with tweeters at ear level, this
downward sloping curve sounds like it is distinctly lacking in the
treble, but it sounded good in the theaters. THX has no doubt continued
to study this, but IMO modern movie theater sound (professional and
home) does not sound better -- except in bass extension -- than the warm
magnetic sound tracks in the 70 mm days, and some new movies sound
worse. I imagine that THX and Audyssey would share any new data, since
they are sort of brother companies, and Thomas & Chris have been
involved with both. The Audyssey dip in the highs may be a new take on
all this old stuff, customized to home listening, but I wish they would
share their methods and data online.

[Rudy81]

I don't beleive Audyssey XT is the same in all pre/pro offerings. My integra, for example, does not offer a flat option at all. Also, it does not have 'sliders' to allow that kind of EQ modification. IIRC, different manufacturers offer different variations. As a matter of fact, even with Audyssey Pro, the Integra does not present the option of a 'flat' response. Of course, you can modify the response as desired (within some limits) with the Pro version. Options with my Integra and Audyssey Pro are HF rolloff 1, HF rolloff 2, and SMPTE 202M....no flat option. The Pro manual has a long explanation as to why 'flat' is not offered....just because a curve 'looks' flat, doesn't mean it will sound 'flat' at the listening position due to driver/horn directionality.

The 'dip' you may be referring to is called "Mid range compensation". In the Pro version, it can be removed.

I have added a 'house curve' to my results to get a more all around pleasing sound.

[Rudy81]

Out of curiosity, I looked at all the Pro manuals for the various other pre/pro manufacturers. It turns out none of them have a 'flat' curve offering with the Pro kit. Every one of them has two HF rolloff option and the SMPTE option.

[garyrc]

How do they describe the SMPTE 202M curve? Is that option meant to simulate the SMPTE theater curve, but modified for home sized rooms? Is that what you meant by a "house curve?"

Stereophile ran an editorial (many years ago) called "Down with Flat." Despite this, I think flat can sound good from one chair, and less so from another, possibly due to the directionality issue the Pro manual cites. Still I wouldn't mind starting with flat from the sweet spot, then change if necessary. I think I have experienced the "flat not sounding flat" problem in the past.

[Rudy81]

The SMPTE curve is described as follows: "SMPTE 202M curve is an international standard for the high frequency roll-off applied in a typical 500-seat movie theater. It is appropriate for professional mixing spaces and dubbing stages that must be calibrated for film sound postproduction. It an also be used in extremely large playback spaces (room volume greater than 5000 cu. ft.)"

A house curve is a customized curve you create using an equalizer of some sort to achieve a more 'flat' sounding soundfield. Since our ears don't perceive all frequencies at the same loudness level, see Fletcher-Munson curves, you create what is called a house curve to boost the lo end and reduce the highs to create a more balanced sounding response.

The following article can describe a house curve way better than I can. http://www.hometheatershack.com/forums/rew-forum/96-house-curve-what-why-you-need-how-do.html

Needless to say, sound in your room is a very personal experience. Over the years, I have heard that chasing a 'flat' sound in your listening spot is a waste of time. Very different than engineering a speaker to be as flat as possible. Our ears don't hear all frequencies at equal loudness, so no point in listening to a 'flat' response. If you did, it wouldn't be really flat, but rather skewed by human hearing.

[garyrc]

Rudy81, thanks for the link to the house curve article. A very good read. The best movie sound I've ever heard was in Todd-AO theaters in the late '50s, the '60s and the '70s. These magnetic 6 channel tracks were very warm and dynamic, and members of our orchestra found them very realistic. As orchestra members, we were used to being close to the instruments, and hearing strong high frequencies, so we would be expected to want a brghter sound (if it was to be realistic) than people who usually sat farther back in a concert hall. Yet Todd-AO sounded very real, and "flat" to our then young ears. I later found out that the sound in those Todd-AO theaters began to roll off steeply at 12K Hz because of the drivers they used, and because of the house curve the decline started lower, I think - 3dB at about 4.5K, and down about 9 dB at the top. They sounded rich and real until new equipment was installed in one of these same theaters for Star Wars in 1977. The sound for Star Wars in that theater was too bright -- one critic said "... a knife in the ear." From then on several soundtracks were too bright in that theater. Go figure.

Our ears don't hear all frequencies at equal loudness, so no point in listening to a 'flat' response. If you did, it wouldn't be really flat, but rather skewed by human hearing.

But, if the playback system and the room (in one "sweet" chair) were both flat as measured by instruments rather than ears, and if the music was at the same SPL at home as in a concert hall at the time the recording was made, wouldn't our skewed human hearing hear both the live sound and the home playback with the same "curve," i.e., whichever of the Fletcher-Munsen curves corresponded to that particular same SPL, at home and at the recording site?[]

[Rudy81]

But, if the playback system and the room (in one "sweet" chair) were both flat as measured by instruments rather than ears, and if the music was at the same SPL at home as in a concert hall at the time the recording was made, wouldn't our skewed human hearing hear both the live sound and the home playback with the same "curve," i.e., whichever of the Fletcher-Munsen curves corresponded to that particular same SPL, at home and at the recording site?

I would think this situation would sound somewhat similar, and if that is what you are after, then you should be set. I'm not really sure the concert hall is really 'flat' across the board.

The more I read and learn about acoustics and human hearing, the more I realize that quite a bit of our experiences are rather personal in nature, although we all try to fit our experience under a common umbrella when we discuss the topic. Right now I'm reading Floyd Toole's book on sound reproduction. This is particularly aimed at the home and small room listener. Quite enlightening and he has a good amount of experiments and observations on how we hear things in a small space vs. a large venue. I have found his comments compelling enough so as to re-evaluate my room treatments, which were patterned after a more professional, studio environment.

Bottom line, if it sounds good to you, then that is what you prefer and is how you should enjoy things. You background likely makes you a very good judge of what is a good reproduction. Most of us don't have enough exposure to live events to make good judgements about accurate reproduction.

[Emilyjery]

If I understand (and I'm still confused, despite reading a great deal of the Audyssey Q & A online), Audyssey's frequency and time domain corrections should provide relatively flat response at the listening positions -- providing that one uses "Audyssey Flat." So, doesn't that mean that the speakers/room would be flatter (when measuring with Room EQ Wizard ) with Audyssey Flat than without? Don't you lose the time domain corrections if you just use Audyssey to set the relative channel gains and the speaker delays

[garyrc]

... Audyssey's frequency and time domain corrections should provide relatively flat response at the listening positions -- providing that one uses "Audyssey Flat." So, doesn't that mean that the speakers/room would be flatter (when measuring with Room EQ Wizard ) with Audyssey Flat than without? Don't you lose the time domain corrections if you just use Audyssey to set the relative channel gains and the speaker delays

• Yes, flatter with Audyssey than without, providing one uses Audyssey Flat
• Yes if you only use Audyssey just to set gains and delays, BUT why do that? You will lose FQ/time corrections if you use your receiver or pre/pro's virtual sliders to change the frequency response curve Audyssey has set -- if I understand (!) Some pre/pros have tone controls that are in the circuit after Audyssey that can be used to slightly change the response without dumping Audyssey. That way you start with a pretty good room correction, then futz around a bit to get "preference, not reference." But you can't use the sliders, at least on my Marantz. The Audyssey pro also has a provision for that, I think.

[merkin]

I've heard of people using those small key chain type lasers to point speakers in a similar manner as above.

I'm not up to date on lasers. If we are aiming at the speakers, do we know that the keychain type or cat toy type lasers won't damage diaphragms, or whatever, in tweeters? If we're aiming at the listening chair, do we need to make sure nobody is sitting there?

All I know about lasers is that Judge Ito asked that they not be pointed at him during the O.J. Trial ... and, of course, what almost happened to James Bond in Dr. No.

as in Startrek place them on "stun"

[Islander]

Try using a laser level. They project light in a stripe that can be set to be vertical or horizontal, and make it very easy to line up all your speakers (6 in my case, plus the sub) in a symmetric pattern.

I start with the centre speaker, set the main speakers equidistant from the centre, then use the laser to line up the inner (the side nearest the centre speaker) sides of the mains with a dummy head form placed at my listening position. That makes them not quite directly aimed at me, but the sweet spot is a bit wider that way.

The surround and rear surrounds are aimed directly at the listening position.

The power output of those small home lasers is measured in milliwatts, so don't worry about doing damage to any surface the beam hits. Although I try to avoid it, I've had the laser beam occasionally bounce off a shiny surface and hit my eyes with no problems. Those "James Bond" industrial lasers have outputs in the hundreds of watts and can do real damage, but the little lasers have a thousand times less power.

The tape measure is only needed to set the position of the speakers and the distances from the listening position, which is easy enough. Using a tape measure to set the speaker direction is not so easy, but with the laser level (available at most hardware stores), the speaker direction can be set easily and repeatably, so it's quick and simple to try different directions to see what sounds best to you.

[consistent]

hi

go to www.cardas.com the 'golden ratio' it does work!