Yes that's in there as well. Some very interesting graphs too of first reflection audibility vs time. It's not so cut and dry as early=bad or early=good, there's a shape to the graphed early->late data that is not at all a straight line. More like a check mark. Direction of reflection is also something he focuses on, especially that sound coming from the sides contributes much more to his term "spaciousness" than sound from the front/back/ceiling/floor. Multichannel is his endpoint, but most of the information in the book is about one or two channel testing at harman.
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there was also government/EU sponsored research project in Europe:
its conclusion was the same:
"reasonably flat power response laterally, is ideal behavior." and "vertical reflections (from the floor to the ceiling) tend to upset our perception"
BeoLab 5 from Bang & Olufsen is the outcome of this project conclusions,
interestingly it's in many ways very similar to ideal speaker according to Toole's Harman research papers, not only from the point of directivity but also bass equalization and so on
best
graaf
"Room treatment and equalisation for optimum ceiling flooder setup."
Would then be a good title too ...
I'd like to explain, what my different "angle of view" is about,
having made lots of different speakers over the years, which had
been placed in different rooms, used by listeners with different
habits. Since i am someone who moves from time to time,
there have been also different rooms i lived in myself.
Speaker and room make up a system, that much is clear.
From the viewpoint of a speaker designer, the speaker's variables
are far more under design control than the properties of the room,
where the speaker under question will be placed.
This holds except for those cases in the professional area, where
the listener/user is able and willing to modify the room drastically
for its listening room purpose.
For the majority of cases, the loudspeaker has to cope with
listening rooms which have a main purpose as living room.
(e.g. wives live there and other often audio disturbing circumstances ..)
This results in the design goal for a loudspeaker to be as robust
against changing room conditions as possible on the one hand,
and to be flexible/equalizable for those variables changing inevitably
with different rooms. If the need for equalization can be mainly reduced
to the bass range, were modal bahaviour and room gain comes into play,
we have reduced the problem quite lot.
My question to every speaker design is:
How universal is this design due to changing listening room conditions ?
Since the ceiling flooder is highly dependent on a specially prepared
room, it has low universality and is - TO ME - not interesting.
It would become interesting if it can be made applicable in a great
variety of room conditons. The proposals i made into that direction,
did not seem to arise much interest from your side.
But the longer this thread runs, the more you have to admit, that there
has to be special room treatment and that equalizing is desirable.
This has taken a lot of time and lots of posts.
Of course the ceiling flooder concept WILL NECESSARILY need a high amount
of room dependent equalisation and maybe adjustable frequency dependent
dispersion as well - to make it cope with different rooms.
If made a commercial product or a diy concept to be shared by others,
you would e.g. need optionally ceiling reflectors for rooms with
absorbtive ceilings. What about ceiling height ?
My current line array design can be placed in nearly every room without
equalizing above 120 Hz. You adjust the subwoofer(s) according level and
position in room and thats it.
It does not care about floor carpets or ceilings beeing absorptive and is
quite benign concerning distance and structure of neighboured walls as well.
Have the side walls 70cm away or 3m, it does not care very much.
The distance to the rear walls is an issue and has to be > 1.2 m,
then they are ready to work.
That is my currrent - surely not the final or perfect - result of
experience with different speaker designs making up a part of the
speaker/room system.
Best Regards
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perhaps, but it was not my intention to exclude other solutions
now flooder is the main topic or one of the main topics and my point is that as such it is expected to come into play without blinking "
"? not at all
perhaps You mix the flooder as such with specific (perhaps optimal) Beveridge placement setup?
but it works fine also in other placement options, actually I never had opportunity to try Beveridge placement, I hoped that someone else would have.
my initial idea was exactly opposite to "specially prepared room":
typical living room
but only because of practical considerations - what You proposed appeared very complex to me, unsuitable for DIY community in which most of us don't have required technical background nor technical equipment to implement such ideas
it were fine ideas though for someone more professional
?? where? when?
if You mean my posts regarding optional deflectors or absorbers in the very vicinity of the flooders - they were all "IF", "optional" suggestions - in my experience with the flooders I had no need to implement any deflectors or absorbers
even if - is it a problem? most of us use some form of equalization
of course high amount, adjustable ad so on
How can You be so sure? Contemporary typical living rooms are rather standardized, we live in an age of Ikea and the likes
check my first post - nowhere and never my aim was a commercial product or even "my diy concept" to be shared, I have no such aspirations because I lack expertise - a fact I have made absolutely clear in my first post
it was just an intuitive idea for TIY - TRY IT YOURSELF
trying it costs nothing - even single driver speakers for mini system would sometimes do to check the idea as such
what about it? why speculate?
El'Ol checked this at His own home, where he has ceiling very unlike to mine, and everything was fine
there are architectural standards - norms - for apartment buildings - You would not find an absorbtive ceiling in a normal living room
and the ceiling height would normally be no less than 2.65 m IIRC
nice! from audiophile perspective
but 0.7 from side walls and 1.2 from rear wall IS an issue in a typical living room of a music lover
not to mention decor and esthetics considerations, they (the speakers) are quite big
flooders are meant to be practically invisible in the room
thank You for sharing Your thoughts
best regards!
graaf
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Yes, maybe we have to distinguish between
"Home music lovers, audiophools and professionals."
I am an audiophool concerning purpose of the room and
listening habits. The current dipol line array design is
adjusted for an audiophool like me and not meant to
be "invisible". Do not forget subwoofer placement.
One has to suffer for audio, otherwise it is no fun.
It is meant to yield performance best possible in a
non professional environment. The concept can be
shared by other audiophools.
If aligned for the "average appartment" the ceiling flooder
may work for many home music lovers living in
comparable rooms. And it has high WAF because invisible.
So everything is fine.
"Home music lovers, audiophools and professionals."
I am an audiophool concerning purpose of the room and
listening habits. The current dipol line array design is
adjusted for an audiophool like me and not meant to
be "invisible". Do not forget subwoofer placement.
One has to suffer for audio, otherwise it is no fun.
It is meant to yield performance best possible in a
non professional environment. The concept can be
shared by other audiophools.
If aligned for the "average appartment" the ceiling flooder
may work for many home music lovers living in
comparable rooms. And it has high WAF because invisible.
So everything is fine.
So I am not sure what you meant in the first place. But than my error came first.
If you agree to "horizontal directivity should be constant in any case, and vertical dispersion shoul be narrow" - doesn`t that fundamentally contradict your flooder concept? I was under the impression that you were beaming something to the ceiling. That would not be "narrow vertical dispersion" in my vocabulary.
What Geddes is showing in figure 9 of his "Directivity" paper. Whereby it would not be mandatory that the response has rolled off 6 dB at 45°.
Not kidding, but obviously misunderstanding. If there is no huge vertical component in the dispersion of your construction - why do you call it a (ceiling) flooder than?
Could you possibly give a small diagram of the intended dispersion pattern?
Rudolf
Hi,
This is a remarkably succinct coverage of the reasons why people from Floyd Toole and Earl Geddes through Heiner Martion, Holger Fromme and Romy the Kat (and not to forget little old me) make their speaker systems to have as tightly controlled directivity and as consistent and flat directivity index as the design budget and domestic considerations (not everyone likes Holgers and Heiners trumpets of Jericho in their front room) allow.
Ditto.
As concept it will no doubt be of interest to some audiophiles and diyer's, but it needs to come with strict instruction on suitable rooms, ceiling height & constitution, floor constitution and other treatment, kind of the opposite of what I'd call a "room compatible loudspeaker".
Now I pretty much understand why his lordship is SOOOO over the moon with the concept and wishes to evangelise, I think I will leave the thread now to itself, as there is little more point in the debate, for me at least.
Ciao T
This is a remarkably succinct coverage of the reasons why people from Floyd Toole and Earl Geddes through Heiner Martion, Holger Fromme and Romy the Kat (and not to forget little old me) make their speaker systems to have as tightly controlled directivity and as consistent and flat directivity index as the design budget and domestic considerations (not everyone likes Holgers and Heiners trumpets of Jericho in their front room) allow.
Ditto.
As concept it will no doubt be of interest to some audiophiles and diyer's, but it needs to come with strict instruction on suitable rooms, ceiling height & constitution, floor constitution and other treatment, kind of the opposite of what I'd call a "room compatible loudspeaker".
Now I pretty much understand why his lordship is SOOOO over the moon with the concept and wishes to evangelise, I think I will leave the thread now to itself, as there is little more point in the debate, for me at least.
Ciao T
I only checked the OGGs. Looks like VLC applies too much gain in the digital domain. I found iTunes having similar problems. Unfortunately I don't know of a way to monitor OS X's internal remixer correctly. Cabling is Mac mini > optical out > AVR
Best, Markus
Making progress, VLC had the default volume at 200% (of what?). Setting it to 100% (is that no gain?) moves the volume fader to about 25% to the left. Max. volume is 400% - does that make any sense? Couldn't find any information on how VLC handles volume settings.
Anyway, back to the files: I don't hear anything that would be out of the norm. For a comparison it would make sense when the files would switch from processed to original a couple of times.
Anyway, back to the files: I don't hear anything that would be out of the norm. For a comparison it would make sense when the files would switch from processed to original a couple of times.
I have read the first 8 chapters (140 pages) of Toole's book and I will post some quotes here, mainly for graaf, who doesn't want to buy it.
First some of Toole's thoughts about concert halls:
"...towards the rear of a concert hall, the direct sound is not the primary acoustic event. It may even be inaudible, masked by later acoustical events. Two ears and a brain comprise a powerful acoustical analysis tool, able to extract enormous resulution, detail, and pleasure from circumstances that, when subject to mere technical measurements, seem to be disastrous, Something that in technical terms appears to be impossibly scrambled is perceived as a splendid musical performance."
Forsyth (1985):
"When an orchestra plays at forte level in a compatible-sized room, strong sound reflections can be heard from the side walls and to some extent the ceiling as the music "fills the hall". This criterion of "spacial impression" has been identified as significantly important to the enjoyment of a live concert, and this is reduced when the orchestra is unable to achieve a full-bodied forte, as the early sound reflections seem to be confined to the stage area instead of coming from all directions."
"Many modern halls have become wider, expanding into a fan shape to acommodate more people while retaining good sight lines. Famous acoustician Leo Beranek (1962) notes that "listening to music there is rather like listening to a very fine FM-stereophonic reproduction system in a carpeted living room." ... Michael Forsyth (1985) comments on the tendency, especially in North America, to build "hi-fi concert halls", providing some of the impression of "front row" close to microphone recordings favored in the region. ... their tastes have been cultivated by stereo recordigs that are incapable of reproducing the full-scale envelopment of a great symphony hall. ...[trend going backwards according to a new study]... They link these trends to advances in room acoustical technologies, and the result is a more spacious, enveloping, listening experience - less like stereo."
"In live performances, it is the auditory illusion of a sound source that is wider than the visible sources; this is considered to be a strongly positive attribute of a concert hall. Perhaps becouse they lack other pleasures of live performances, many audiophiles have come to think that pinpoint localizations are a measure of excellence,..."
"a sense of being in a large space, of being surrounded by a diffuse array of sounds not associated with any localizable sound images. This is regarded as perhaps the more important component of spaciousness, differentiating good concert halls from poor ones."
"When I had the good fortune to attend rehearsals and performances of a symphony orchestra in Vienna's Musikverein, one of the most celebrated halls in the world, I was frankly not ready for the intensity of the spacial impression - the hall was indeed "full" and the envelopment was profound. It was greatly pleasurable, but for a person habituated to more modern, larger, halls and after many years of exposure to two-channel sound, the first impression was one of a surprise. It occured to me that I and my audiophile acquaintances would probably consider such an illusion to be artificially overdone if we were to hear it through a multichannel audio system."
First some of Toole's thoughts about concert halls:
"...towards the rear of a concert hall, the direct sound is not the primary acoustic event. It may even be inaudible, masked by later acoustical events. Two ears and a brain comprise a powerful acoustical analysis tool, able to extract enormous resulution, detail, and pleasure from circumstances that, when subject to mere technical measurements, seem to be disastrous, Something that in technical terms appears to be impossibly scrambled is perceived as a splendid musical performance."
Forsyth (1985):
"When an orchestra plays at forte level in a compatible-sized room, strong sound reflections can be heard from the side walls and to some extent the ceiling as the music "fills the hall". This criterion of "spacial impression" has been identified as significantly important to the enjoyment of a live concert, and this is reduced when the orchestra is unable to achieve a full-bodied forte, as the early sound reflections seem to be confined to the stage area instead of coming from all directions."
"Many modern halls have become wider, expanding into a fan shape to acommodate more people while retaining good sight lines. Famous acoustician Leo Beranek (1962) notes that "listening to music there is rather like listening to a very fine FM-stereophonic reproduction system in a carpeted living room." ... Michael Forsyth (1985) comments on the tendency, especially in North America, to build "hi-fi concert halls", providing some of the impression of "front row" close to microphone recordings favored in the region. ... their tastes have been cultivated by stereo recordigs that are incapable of reproducing the full-scale envelopment of a great symphony hall. ...[trend going backwards according to a new study]... They link these trends to advances in room acoustical technologies, and the result is a more spacious, enveloping, listening experience - less like stereo."
"In live performances, it is the auditory illusion of a sound source that is wider than the visible sources; this is considered to be a strongly positive attribute of a concert hall. Perhaps becouse they lack other pleasures of live performances, many audiophiles have come to think that pinpoint localizations are a measure of excellence,..."
"a sense of being in a large space, of being surrounded by a diffuse array of sounds not associated with any localizable sound images. This is regarded as perhaps the more important component of spaciousness, differentiating good concert halls from poor ones."
"When I had the good fortune to attend rehearsals and performances of a symphony orchestra in Vienna's Musikverein, one of the most celebrated halls in the world, I was frankly not ready for the intensity of the spacial impression - the hall was indeed "full" and the envelopment was profound. It was greatly pleasurable, but for a person habituated to more modern, larger, halls and after many years of exposure to two-channel sound, the first impression was one of a surprise. It occured to me that I and my audiophile acquaintances would probably consider such an illusion to be artificially overdone if we were to hear it through a multichannel audio system."
Now you know what Toole's favorite music genre is and why he advocates lateral reflections for 2 channel sound reproduction. Roughly 99% of all other musical genres are NOT played in concert halls. 380 pages to go
Markus - completely correct.
A cursious comment since it cannot possibly be true physically, such a comment would reflect a nonlinear situation. The ratio of the direct to reflecting signal is independent of the SPL level. Perhaps what is meant is that there is greater temporal masking at low levels than at high levels which allows the direct field to surpress the reflections at lower signal levels. There is some evidence for this, some of which is my own, but as an established fact, it most certainly is not. And in 1985 this comment would have been completely without any evidential support. (Not that that is anything new in audio.)
Parts of Toole's explanation of the precedence effect:
“Within the precedence effect fusion interval, there is no masking – all of the reflected (delayed) sounds are audible, making their contributions to timbre and loudness, but the early reflections are not heard as spatially separate events. They are perceived as coming from the direction of the first sound; this, and only this, is the essence of the “fusion”. The widely held belief that there is a “Haas fusion zone,” approximately the first 20 ms after the direct sound, within which everything gets innocently combined, is simply untrue.”
“It is important to notice that these very strongly worded categorical statements all emphasize that there is an accumulation of information from the various members of the sequence. It is quite incorrect to assume that the precedence effect is some sort of masking phenomenon which, by blocking out the later arrivals of the signal, prevents the auditory system from being confused. Quite to the contrary, those arrivals that come in within a reasonable time after the first one actively contribute to our knowledge of the source.”
“Within the precedence effect fusion interval, there is no masking – all of the reflected (delayed) sounds are audible, making their contributions to timbre and loudness, but the early reflections are not heard as spatially separate events. They are perceived as coming from the direction of the first sound; this, and only this, is the essence of the “fusion”. The widely held belief that there is a “Haas fusion zone,” approximately the first 20 ms after the direct sound, within which everything gets innocently combined, is simply untrue.”
“It is important to notice that these very strongly worded categorical statements all emphasize that there is an accumulation of information from the various members of the sequence. It is quite incorrect to assume that the precedence effect is some sort of masking phenomenon which, by blocking out the later arrivals of the signal, prevents the auditory system from being confused. Quite to the contrary, those arrivals that come in within a reasonable time after the first one actively contribute to our knowledge of the source.”
Evaluations of listener preferences, taken from Toole's book:
“Listeners appeared to prefer the sound from wide-dispersion loudspeakers with somewhat colored off-axis behaviour to the sound from a narrow-dispersion loudspeaker with less colored off-axis behavior. In the years since then, it has been shown that improving the smoothness of the off-axis radiated sound pushes the subjective ratings even further up, so it is something not to be neglected. Perhaps related to this is the acoustical crosstalk associated with the phantom center image. This coloration cannot be ignored in a situation where the direct sound is strong. Early reflections from different directions tend to fill the interference dip, making the spectrum more pleasantly neutral.”
“Using only professional sound engineers as listeners, they found that narrow-dispersion loudspeakers were required for good reproduction of voices in radio dramas; dance and popular music was also desirably “aggressive” with “highly directed” loudspeakers. The majority of the same listeners, however, preferred wide-dispersion loudspeakers for the reproduction of symphonic music at home. In the control room, though, only about half of them felt that they could produce recordings with such loudspeakers.”
“Moulton et al. (1986) performed informal listening evaluations of forward-firing designs compared to a horizontally omnidirectional loudspeaker. It was concluded that with “the stereophonic omnidirectional playback system, the musical essence of the sound seems more palpable, more enduring, and more directly accessible than we have experienced with other loudspeaker systems.”… More recently, after more investigation, Moulton (1995) stated, “It appears that broad horizontal dispersion, with the engagement of a specularly responsive set of side walls, yields preferred sonic quality for the stereophonic playback of music, both in terms of spectral accuracy and also in terms of stereophonic illusion, image and entertainment quality.””
“[Flindell et.al. (1991)] Ten of the listeners were experienced audio industry persons, and ten were naïve. In general, the naïve listeners preferred the widest possible high-frequency dispersion; the experienced listeners liked it, too, but also about equally liked a configuration that simulates a dominant direct sound above 500 Hz. Perhaps the listening circumstances allowed professionals to shift between listening modes – recreational and working… The natural concern that wide dispersion and the attendant strong early reflections “would lead to degraded stereo imaging was not confirmed by the experienced listeners using rating scales and blind presentations of audio material.” Providing a contrasting point of view, Newell and Holland (1997) present a reasoned discussion of the requirements for control-room acoustical treatment (and, by inference, loudspeaker directivity). They favor the elimination of all lateral and vertical reflections – a near anechoic space, placing listeners in a direct-sound field. They conclude that “spaceousness and the resolution of fine details are largely mutually exclusive. Spaceousness should… be an aspect of the final reproduction environment.” There is no doubt that, listening to direct sound only, recording engineers may recognize the callously stark special presentation of hard-panned left and right stereo images and be motivated to remedy it, unless this turns out to be another preference associated with the professional side of the industry. Not to be ignored in any situation in which reflected sounds have been removed is the fact that the acoustical crosstalk that plagues stereo phantom images is present in its naked ugliness, without any compensation from reflected sounds. One hopes that recording engineers in these situations do not attempt to remedy it with equalization. If they do, their compensation would be excessive for normally reflective rooms and totally wrong if ever the program is replayed through an upmix algorithm and the center image emerges from a center loudspeaker.”
“Why do recording and mixing engineers prefer to listen with reduced lateral reflections? Perhaps they need to hear things that recreational listeners don’t. This is a popular explanation, and it sounds reasonable, but experiments reported in Section 6.2 indicate that we humans have a remarkable ability to hear what is in a recording in spite of room reflections – lots of them. But there is an alternative explanation, based on the observation that some listeners can become sensitized to these sounds an hear them in an exaggerated form. Ando et.al. (2000) found that musicians judge reflections to be about seven times greater than ordinary listeners, meaning that they derive a satisfying amount of spaceousness from reflections at a much lower sound level than ordinary folk: “Musicians prefer weaker amplitudes than listeners do.” It is logical to think that this might apply to recording professionals as well, perhaps even more so, because they create artificial reflections electronically and manipulate them at will while listening to the effects. There can be no better opportunity for training and/or adaption. In fact, it is entirely reasonable to think that acousticians who spend much of their lives moving around in rooms while listening to revealing test signals can become sensitized to aspects of sound fields that ordinary listeners blithely ignore. This is a caution to all of us who work in the field of audio and acoustics. Our preferences may reflect accumulated biases and therefore may not be the same as those of our customers.”
“Listeners appeared to prefer the sound from wide-dispersion loudspeakers with somewhat colored off-axis behaviour to the sound from a narrow-dispersion loudspeaker with less colored off-axis behavior. In the years since then, it has been shown that improving the smoothness of the off-axis radiated sound pushes the subjective ratings even further up, so it is something not to be neglected. Perhaps related to this is the acoustical crosstalk associated with the phantom center image. This coloration cannot be ignored in a situation where the direct sound is strong. Early reflections from different directions tend to fill the interference dip, making the spectrum more pleasantly neutral.”
“Using only professional sound engineers as listeners, they found that narrow-dispersion loudspeakers were required for good reproduction of voices in radio dramas; dance and popular music was also desirably “aggressive” with “highly directed” loudspeakers. The majority of the same listeners, however, preferred wide-dispersion loudspeakers for the reproduction of symphonic music at home. In the control room, though, only about half of them felt that they could produce recordings with such loudspeakers.”
“Moulton et al. (1986) performed informal listening evaluations of forward-firing designs compared to a horizontally omnidirectional loudspeaker. It was concluded that with “the stereophonic omnidirectional playback system, the musical essence of the sound seems more palpable, more enduring, and more directly accessible than we have experienced with other loudspeaker systems.”… More recently, after more investigation, Moulton (1995) stated, “It appears that broad horizontal dispersion, with the engagement of a specularly responsive set of side walls, yields preferred sonic quality for the stereophonic playback of music, both in terms of spectral accuracy and also in terms of stereophonic illusion, image and entertainment quality.””
“[Flindell et.al. (1991)] Ten of the listeners were experienced audio industry persons, and ten were naïve. In general, the naïve listeners preferred the widest possible high-frequency dispersion; the experienced listeners liked it, too, but also about equally liked a configuration that simulates a dominant direct sound above 500 Hz. Perhaps the listening circumstances allowed professionals to shift between listening modes – recreational and working… The natural concern that wide dispersion and the attendant strong early reflections “would lead to degraded stereo imaging was not confirmed by the experienced listeners using rating scales and blind presentations of audio material.” Providing a contrasting point of view, Newell and Holland (1997) present a reasoned discussion of the requirements for control-room acoustical treatment (and, by inference, loudspeaker directivity). They favor the elimination of all lateral and vertical reflections – a near anechoic space, placing listeners in a direct-sound field. They conclude that “spaceousness and the resolution of fine details are largely mutually exclusive. Spaceousness should… be an aspect of the final reproduction environment.” There is no doubt that, listening to direct sound only, recording engineers may recognize the callously stark special presentation of hard-panned left and right stereo images and be motivated to remedy it, unless this turns out to be another preference associated with the professional side of the industry. Not to be ignored in any situation in which reflected sounds have been removed is the fact that the acoustical crosstalk that plagues stereo phantom images is present in its naked ugliness, without any compensation from reflected sounds. One hopes that recording engineers in these situations do not attempt to remedy it with equalization. If they do, their compensation would be excessive for normally reflective rooms and totally wrong if ever the program is replayed through an upmix algorithm and the center image emerges from a center loudspeaker.”
“Why do recording and mixing engineers prefer to listen with reduced lateral reflections? Perhaps they need to hear things that recreational listeners don’t. This is a popular explanation, and it sounds reasonable, but experiments reported in Section 6.2 indicate that we humans have a remarkable ability to hear what is in a recording in spite of room reflections – lots of them. But there is an alternative explanation, based on the observation that some listeners can become sensitized to these sounds an hear them in an exaggerated form. Ando et.al. (2000) found that musicians judge reflections to be about seven times greater than ordinary listeners, meaning that they derive a satisfying amount of spaceousness from reflections at a much lower sound level than ordinary folk: “Musicians prefer weaker amplitudes than listeners do.” It is logical to think that this might apply to recording professionals as well, perhaps even more so, because they create artificial reflections electronically and manipulate them at will while listening to the effects. There can be no better opportunity for training and/or adaption. In fact, it is entirely reasonable to think that acousticians who spend much of their lives moving around in rooms while listening to revealing test signals can become sensitized to aspects of sound fields that ordinary listeners blithely ignore. This is a caution to all of us who work in the field of audio and acoustics. Our preferences may reflect accumulated biases and therefore may not be the same as those of our customers.”