In my previous blog #17 I mentioned that:
“But for an average audio enthusiast [to use] “a hardware language” of dealing with [the audio equipment technical aspects] is a horrendously daunting proposition.
It’s much more productive [for finding a successful solution of their concrete tasks], in their case, to resort to some higher level “languages” which can “code” some relevant algorithms of common sense, emotional intelligence and lucid analogies.
That’s why most of our own StereoPravda SPearphone current customers are not hardware “buffs”, we do not even try to appeal to our potential customers with a “hardware” language, as they, as a rule, don’t even speak it.
And that’s why, up until now, people who speak only “hardware” languages don’t, really, demonstrate that they get the essence of our solutions”.
It goes without saying that the description of “the essence” of a product can be approached from some different angles, for instance, slanted towards its ideology, its positioning on the market, its technical or production aspects, and so on.
In this blog I will try to use some construction aspects of our ear monitors to demonstrate their “main essence”.
In accordance with the above quote, to describe the design principle behind our solutions, wherever it’s possible, I will try to refrain from the “hardware” language, and will try to mostly use a language “of higher level” (my previous blog dwells on the issue a little further) which is more appropriate to operate in the domain of “common sense, emotional intelligence and lucid analogies”, the same domain where we found all of our solutions.
Obviously, there is a reason behind our website motto where we claim that “We Pass the Torch of “[“Home”] High End Audio’s Old Values to the New Generation of [“Portable”] Audiophiles”.
What do we mean by that?
Actually, what we mean by that is that the goal of our portable solutions – our ear monitors and our dedicated electronic equipment - is to deliver the same sound attributes as we got accustomed to through all these years of listening to well installed High End Audio systems at home.
Including very similar soundstage presentation.
In my blog #8 I described in a lot of details why, within the whole spectrum of various headphones’ and earphones’ techniques, the technique of deeply inserted multi-driver “In-The-Ear Monitor”(IEMs), the one that we utilize in all of our StereoPravda “Spearphone”-series of products, is the most capable for accomplishing of the above goal.
Both that blog and the blog #7 more thoroughly dwell on some of the issues raised in this one, and provide some additional details on the subjects just touched upon here.
So, let’s get down to business.
In home audiophile community it’s universally accepted that if a sufficient condition to obtain the highest quality sound reproduction at home is to have an access to an appropriately treated listening room and some highest quality audio components, then as a necessary one is that you must to comply, as close as possible, with all the following “HOME AUDIO AXIOMS”:
THE HOME AUDIO AXIOM #1:
All the “key” drivers in the loudspeakers and the listener’s ears must be in the same room.
(universally accepted in audiophile community)
THE HOME AUDIO AXIOM #2:
There must be no obstacles (for example, no substantially extended acoustic waveguides or no heavy curtains) between the loudspeakers “key” drivers and the listener’s ears.
(almost universally accepted in audiophile community)
(Why “almost”: as some waveguides, “horns” and other acoustic loading speaker components sometimes are being used in some loudspeaker systems.
When this happens, in my book, such design approaches disqualify the corresponding solutions from to be considered as “true representatives of High End Audio”.
Even if in “in some other people’s books” such solutions are treated, on the opposite, with an outmost respect, as a rule, those “obstacles’” longitude dimension are relatively small compared to the distance to the listener’s ears).
THE HOME AUDIO AXIOM #3:
The listener’s ears must “see” the loudspeakers’ “key” drivers directly in front of them.
(universally accepted in home audiophile community)
THE HOME AUDIO AXIOM #4:
All the “key” drivers in the speakers must be “on-the-common-axis”.
(universally accepted in home audiophile community)
THE HOME AUDIO AXIOM #5:
Both the speakers and, consequently, their drivers must be “correctly” positioned within the room.
(universally accepted in home audiophile community)
THE HOME AUDIO AXIOM #6:
The listener must be equidistant from the loudspeakers.
(universally accepted in home audiophile community)
THE HOME AUDIO AXIOM #7:
The listener must be in “the near field” of the “key” drivers’ acoustic radiation.
(universally accepted in home audiophile community)
(That is he or she must be positioned in a spot in which the intensity of the direct sound radiation from the “key” drivers substantially dominates not only over all sorts of sound responses of the room itself, but also substantially dominates over the external acoustic noise floor in it (including the noise coming through the walls from adjacent rooms and the neighbors).
THE HOME AUDIO AXIOM #8:
The listener’s ears must be positioned (approximately) “on-axis” with the speakers’ “key” drivers.
(universally accepted in home audiophile community)
THE HOME AUDIO AXIOM #9:
The listener’s ears must stay open during the whole period of a system’s auditioning, while the music soundstage position must be perceived by the listener outside of the head directly in front of him/her.
(universally accepted in home audiophile community)
(…Even if the former is “easily said than done” during the most of the audio demos I’ve been exposed to.)
THE HOME AUDIO AXIOM #10:
Both a certain “correct” amplitude/frequency response, and a flat phase/frequency response at the listener ears’ position must facilitate obtaining the highest audiophile quality.
(universally accepted in home audiophile community)
(That’s why a very significant effort is taken in the most advanced audio set ups, as a rule, all “multi-way” ones, to implement the best quality crossover filter networks.)
THE HOME AUDIO AXIOM #11:
All audio systems of the highest caliber must be not only (passive) “multi-way” ones, but, most importantly, they must be “active multi-way” ones, that is they should utilize several separate power amplifiers per frequency band in a stereo channel with an “actively” adjustable external electronic crossover.
(I am hoping that it’s universally accepted in home audiophile community)
THE HOME AUDIO AXIOM #12:
In no-holds-barred home audio systems the connecting cables’ design and execution must be directly correlating with their sonic qualities as a top priority, and must pay a secondary attention to their mechanical properties and their “tear and wear” reliability.
(universally accepted in home audiophile community)
(That’s why some of them resemble the garden hoses, and that’s why it looks as there is no price figure for a cable that can stop a hardcore audiophile buff to get a second mortgage on his house to pay for his/her “cable of fancy”.)
The same can be said about the audio cable connectors’ construction, which, within the existing connectors’ standards, must strive for the best sound by any means possible, and must not pay too much attention to such secondary aspects of their design such as mechanical reliability from every day use.
(universally accepted in home audiophile community).
Any objections yet? I am hoping that not.
Yes, I am aware that the list above is using some simplifications and can be slightly modified in various directions, but I formulated it the way that better corresponds to the considered here subject matter.
Now, if we’d look at the compliance of a typical auditioning of music via some typical In-The-Ear Monitors (IEMs), especially typical multi-driver ones, with the above list of the “HOME AUDIO AXIOMS”, and then, if we’d draw some common sense analogies, where:
- “the loudspeakers” – are the total configuration of the drivers within IEMs;
- “the primary listening room” – is the “operational” volume of the ear canal, defined by the ear canal’s acoustic isolation surface (the isolating surfaces of an individual ear mold material or the isolating surfaces of a “universal” silicon earphone tip) and the tympanic membranes surface;
- and “the listener” is the listener’s two middle ears with his two tympanic membranes acting as his “ears”,
we can come up with some following useful conclusions about the conditions in which such IEMs music listening is taking place.
Here we go:
- THE TYPICAL IEMs “AXIOM” #1:
(A typical IEMs’ design approach and/or an ear canal installation method which DO NOT ALLOW to even minimally COMPLY WITH THE HOME AUDIO AXIOM #1):
All “the loudspeakers’”/IEMs’ ”key” drivers are located outside ear canal’s “operational” volume.
In other words, in a case of a typical IEM, all their “key” drivers are located outside the “primary listening room”.
(which completely DOES NOT comply with THE HOME AUDIO AXIOM #1);
- THE TYPICAL IEMs’ “AXIOM” #2:
(A typical IEMs’ design approach and/or an ear canal installation method which DO NOT ALLOW to even minimally COMPLY WITH THE HOME AUDIO AXIOM #2):
There are extended “obstacles” on a sound propagation path between “the listener ears”/tympanic membranes and “the loudspeaker’s”/IEMs’ “key” drivers; namely, the sound wave guides (long and narrow tubes or bores drilled in the ear mold material).
As a rule, there are also some additional obstacles of a different kind: some barrier acoustic filters installed within the IEMs’ sound channels.
(which completely DOES NOT comply with THE HOME AUDIO AXIOM #2);
- THE TYPICAL IEMs’ “AXIOM” #3:
(A typical IEMs’ design approach and/or an ear canal installation method which DO NOT ALLOW to even minimally COMPLY WITH THE HOME AUDIO AXIOM #3):
The “listener ears”/tympanic membranes do not “see” the “loudspeaker’s”/IEMs’ “key”
drivers directly in front of them.
(which completely DOES NOT comply with THE HOME AUDIO AXIOM #3);
- THE TYPICAL IEMs’ “AXIOM” #4:
(A typical IEMs’ design approach and/or an ear canal installation method which DO NOT ALLOW to even minimally COMPLY WITH THE HOME AUDIO AXIOM #4):
As a rule, all the “key” drivers in a typical IEM are not on a common axis (pic. 1).
(which completely DOES NOT comply with THE HOME AUDIO AXIOM #4);
- THE TYPICAL IEMs’ “AXIOM” #5:
(A typical IEMs’ design approach and/or an ear canal installation method which DO NOT ALLOW to even minimally COMPLY WITH THE HOME AUDIO AXIOM #5):
A typical IEM design application does not treat “the primary listening room”/the ear canal’s
“operational” volume environment as a variable to implement some work on.
Any individual reconfiguration of this space or any acoustic “treatment” of it is considered
practically impossible.
But the worst offence of all is that the vast majority of the drivers (and their “sound channels”) in “the loudspeakers”/IEMs, (especially, the multi-driver ones), in relation to the physical configuration of “the primary listening room”/ear canal’s» operational volume, are usually installed (or drilled) in a very chaotic and random manner (pic.1).
(which completely DOES NOT comply with THE HOME AUDIO AXIOM #5);
- THE TYPICAL IEM’s “AXIOM” #6:
(A typical IEMs’ design approach and/or an ear canal installation method which DOES COMPLY WITH THE HOME AUDIO AXIOM #6):
In any correctly positioned IEM “the listener’s ears”-both of his tympanic membranes are always automatically positioned equidistant from both of “the loudspeakers”-the IEMs.
(a sigh of relief…)
(which completely DOES comply with THE HOME AUDIO AXIOM #6);
- THE TYPICAL IEMs’ “AXIOM” #7:
(A typical IEMs’ design approach and/or an ear canal installation method which DO NOT ALLOW to even minimally COMPLY WITH THE HOME AUDIO AXIOM #7):
As the typical IEM “key” drivers are located outside “the primary listening room” of the ear canal “operational” volume, there is no way we can talk about “near field” listening conditions, right?
The latter statement is a result of “the near field” definition: “the near field” is
where the direct (that is unhindered, without any obstacles on its way) sound radiation intensity from the drivers in a loudspeaker substantially dominates over all sorts of sound intensities from indirect (sic!) sound distortions, both from within the room (inside the room reflections and resonances), and from without it (outside noise, noise from adjacent rooms, the neighbors, etc).
In typical IEMs such “indirect” sound inputs arrive, first, from propagation within the sound wave guides (resonances, reflections, etc), and after completing that path, similar distortions continue to add up while the sound waves start to travel within the whole extension of the”operational” volume (from which it follows that, actually, the smaller the ear canal “operational” volume, the better).
Also, in the case of a typical IEM, a significant “adjacent” input is added to the direct sound intensity perceived by “the listener”/the middle ear - via the adjacent sonic mechanism of the “bone conduction”, which doesn’t help in obtaining the conditions necessary for “the near field” perception of the direct sound.
The perception of sound via “bone conduction” is amplified by the pronounced “occlusion” effect which is increased by the typical IEM’s acoustic seal positioning in the most inappropriate spot for it: that is, typically, at the very entrance to the ear canal (the latter would be very similar to the external noise that you’d hear if you would watch a TV and your neighbors across the wall would have cracked suddenly the volume of the same TV channel as yours up to its maximum).
(which completely DOES NOT comply with THE HOME AUDIO AXIOM #7);
- THE TYPICAL IEMs’ “AXIOM” #8:
(A typical IEMs’ design approach and/or an ear canal installation method which DO NOT ALLOW to even minimally COMPLY WITH THE HOME AUDIO AXIOM #8):
The “listener ears”/his tympanic membranes are not directly on axis with the “key” drivers of the typical “loudspeakers”/IEMs’ (pic. 1 is, again, a good example of what I am talking about here).
The same is true about “the main sound propagation axis within the ear channel”: the most of the typical IEM/s” key” drivers are substantially “off” it.
(which completely DOES NOT comply with THE HOME AUDIO AXIOM #8);
- THE TYPICAL IEMs’ “AXIOM” #9:
(A typical IEMs’ design approach and/or an ear canal installation method which DO NOT ALLOW to even minimally COMPLY WITH THE HOME AUDIO AXIOM #9):
The listener’s ears are strongly plugged by the typical IEMs, so, as opposed to home audio “outside-the-head” sounds imaging, the typical IEMs produce images “inside-the-head”.
The infamous “ear canal occlusion” effect exacerbates this problem even more.
(which completely DOES NOT comply with THE HOME AUDIO AXIOM #9);
- THE TYPICAL IEMs’ “AXIOM” #10:
(A typical IEMs’ design approach and/or an ear canal installation method which DO NOT ALLOW to even minimally COMPLY WITH THE HOME AUDIO AXIOM #10):
Due to unsophisticated design and poor quality of band-pass filters utilized in typical multi-drivers/”multi-way” IEMs some dramatic phase shifts and “incorrect” amplitude-frequency responses are created, which result in poor sound definition and dullness in music presentation.
Despite the detrimental impact of such “cut-the-corners” filtering approach on the earphones’ sound quality it is being routinely used by all the typical IEM manufacturers (you can see a typical implementation of the latter in the background of the pic.1).
Compared to the home audio, where “passive” filtering networks’ design and implementation is not limited by their physical dimensions and weight, due to the obvious restraints of portable audio application, the multi-driver/“multi-way” IEMs’ “passive” filtering networks demonstrate substantially more inferior specs and sound quality.
Using crude wide band barrier aсoustic filters within sound wave guides on the way of sound propagation as some “Band-Aids” to mitigate the problems of inferior electrical “passive” filtering networks and driver resonances, the typical IEM manufacturers, with all the benefit of the doubt towards them mobilized by me, instead of trying to remedy these problems simply prefer to “cover their head in sand” over this issue.
(which completely DOES NOT comply with THE HOME AUDIO AXIOM #10);
- THE TYPICAL IEMs’ “AXIOM” #11:
(A typical IEMs’ design approach and/or an ear canal installation method which DO NOT ALLOW to even minimally COMPLY WITH THE HOME AUDIO AXIOM #11):
Nevertheless, all the current crops of multi-driver/“multi-way” IEMs, even the best ones,
continue to exclusively utilize crude “passive” filtering networks and barrier acoustic filters.
There is not a single reputable “active-multi-way” IEM model I am currently aware of which is supplied with a “multi-way” external electronic crossover which can be used for “active” adjustments of IEMs overall sound, and which, correspondently, is designed to be simultaneously used in the “active” “multi-way” mode with several portable power amplifiers.
The latter approach is capable of getting rid of the most of the “passive” filtering networks’ problems in ear monitors.
(which completely DOES NOT comply with THE HOME AUDIO AXIOM #11);
- THE TYPICAL IEMs’ “AXIOM” #12:
(A typical IEMs’ design approach and/or an ear canal installation method which DO NOT ALLOW to even minimally COMPLY WITH THE HOME AUDIO AXIOM #12):
With just a single glimpse at a typical IEM cable it becomes obvious that it is not designed with the sonic priorities in mind.
On the opposite, it’s undeniable that the other aspects of its construction – the mechanical properties and the resistance to “tear and wear” (and, most likely, its minimal cost) are the top priorities in its design and execution.
The same can be said about the typical quality of the connectors used in portable audio.
(which completely DOES NOT comply with THE HOME AUDIO AXIOM #12);
From just above it follows that the legacy combination of TYPICAL IEM “AXIOMS”, indirectly described by the legacy of corresponding typical IEMs’ design approaches and/or ear canal installation methods, fully complies with only one (#6) out of all twelve HOME AUDIO AXIOMS.
The mentioned above “common sense” of the total set of HOME AUDIO AXIOMS, universally accepted in audiophile community, is the direct result of the common (sic!) standards set many years ago and semi-forgotten by now, and also it’s a direct result of many years’ worth of common (sic!) sonic experience.
It was proved with all the certainty that the only way to reach the highest plateau of audiophile experience at home, which is called High End Audio, is to strictly follow all of them, without an exception.
Every audio “buff” knows that by not strictly following even some of the axioms it would lead to significant sound quality degradations, which they have encountered many times with their own experience.
As we’ve got an almost complete discrepancy between the HOME AUDIO AXIOMS and the TYPICAL IEM “AXIOMS” then it’s obvious that a typical home audiophile experience and a typical IEM experience would be dramatically different.
And in my book, from the appropriate sonic “crime and punishment” common sense analogies with home audio, I can quite presume that the typical IEM design approaches and the corresponding ear canal installation methods from above, vs corresponding typical audiophile home solutions, would inevitably result in obvious sonic degradations.
Even leaving the typical sonic attributes of the portable electronics beyond the scope of this discussion, as home audio buffs, compared to their “portable” colleagues, are, at the very least, aware of what should constitute a great home sonic experience, which, to reiterate one more time, can be realized only by strict compliance with the whole set of the HOME AUDIO AXIOMS, it becomes as no surprise that the quality of a typical IEMs’ sound, born, from home audio’s stand point, under the sway of such an inferior pedigree of the current TYPICAL IEM “AXIOMS”, never “stirred their audiophile mojos”.
If we’d use another analogy to get a feeling for a sound quality a “home” audiophile who’s listening to music via typical IEMs would get, then, briefly speaking, what he’d hear would sound very much like the sound he’d get from his high performance home audio rig set up in the living room… except that when he’d be auditioning the stereo system not at the sweet spot position directly in front of the speakers, but from a spot at his kitchen, which, behind a heavy curtain, is connected to his living room via long, narrow and curved corridor.
The last analogy illustrates the sound character you’d inevitable get at “the listening kitchen room” of the typical “operational’ volume of ear canal while listening to music via typical IEMs.
That is when “the loudspeakers” (the total drivers configuration within the IEMs) play inside its chassis (that is inside “the secondary listening room” of “the living room”), and then, to be heard at “the kitchen’s primary listening room” of “operational” volume of ear canal, the sound must travel through not only the whole extension of “sound tubes” of the “universal” IEMs or “sound bores” drilled in some custom ear mold material, but also it must pass through a “heavy curtain” hanging at the kitchen entrance corresponding to the barriers acoustic filters, as a rule, installed within the majority of IEMs’ “sound tubes” or sound “bores”.
In my opinion, this last analogy is very useful to vividly demonstrate the sonic difference between the full compliance with THE HOME AUDIO AXIOMS, in the case of “home” sound quality in “the living room”, where the stereo system is installed and the full compliance with THE TYPICAL IEM “AXIOMS”, in the case of the “portable” system’s after sound at “the kitchen”.
There is no way that under such circumstances high performance sound quality at the“home” “living room” can be close to its “portable” “kitchen’s” after sound, right?
And, what’s even more important, from the “kitchen” perspective, would any effort to improve the sound quality at the “living room” be like “to fire a cannon at sparrows”?
Both of these questions are rhetorical ones…
That’s why, being fully aware of the answers to the last two questions, and in full accordance with the immense pressure from the Zeitgeist, we’ve got no choice but to try, with a help of our unique StereoPravda “SPearphone” ear monitors’ design and installation solutions, figuratively speaking, to “teleport” “the old” stereo system from “the home” “living room” to “the new” “portable” “kitchen”.
We’re trying to achieve such “teleportation” BY BRINGING all twelve of StereoPravda “Spearphone” IEMs “AXIOMS”, which lay in foundation of our IEMs’ design approach, ear canal installation methods and capabilities of our dedicated electronic solutions, as much as practically possible, IN FULL COMPLIANCE with all twelve of THE HOME AUDIO AXIOMS.
We do this by applying the following techniques (using the same set of analogies as for THE TYPICAL IEMs’ “AXIOM”):
- THE StereoPravda “SPearphone” IEMs’ “AXIOM” #1:
(A StereoPravda “SPearphone” IEMs’ design approach and/or an ear canal installation method and/or a special electronics solution which DO ALLOW, as much as possible, to fully COMPLY WITH THE HOME AUDIO AXIOM #1):
By moving the “naked” outlets of some of our IEMs’ “key” drivers inside “the listening room”-the “operational” volume of ear canal, we position both these drivers and the“listener’s ears”-his tympanic membranes, literally, inside the same “primary listening room”.
(which, as much as possible, DOES fully COMPLY WITH THE HOME AUDIO AXIOM #1);
- THE StereoPravda “SPearphone” IEMs’ “AXIOM” #2:
(A StereoPravda “SPearphone” IEMs’ design approach and/or an ear canal installation method and/or a special electronics solution which DO ALLOW, as much as possible, to fully COMPLY WITH THE HOME AUDIO AXIOM #2):
By getting rid of any “sound wave guides” from some of our “naked” “key” drivers we remove all the obstacles on the path of their free sound radiation.
For the rest of the “secondary’ and the “auxiliary” drivers we’ve got no choice but to strike a compromise and to install some appropriate “sound tubes”at their acoustic outlet ports.
In any case, to minimize the detrimental sonic effects of the “sound tubes” our IEMs design approach is, as much as possible, to minimize their length and to maximize their diameter.
By stripping some of the “key” drivers in our IEMs of their “sound tubes” and by applying the “deep insertion” technique for the IEMs positioning within the ear canal – which facilitates the minimum lengths and maximum diameters for the “sound tubes - we can get rid of the substantial part of all the obstacles on the sound propagations paths.
As the “naked” “key” drivers are the ones closest to the “listener’s ears”- the tympanic membranes, and as they are the ones which have got fairly small impedance and fairly large sensitivity, their sound intensity in the most important, sonically, frequency bands substantially dominates over the sound intensity of all the other drivers within our IEMs.
Also, to avoid the substantial detrimental effect of acoustic barrier filters on the sound quality, we completely refuse to use them in our ear monitors.
In such a way, using “the living room”/”the kitchen” sonic analogy above,
-by “teleporting” our main “naked” “key” drivers from the loudspeakers in “the secondary listening room/”the living room” (IEMs’ chassis) directly to “the kitchen” (“the operational” volume of the ear canal) and properly setting them up in their new listening space;
-by getting rid of “the corridor” between them by substantially widening its cross section and substantially shortening its length (by both substantially widening the “sound tube’s” diameters, and substantially cutting on their lengths);
- and by getting rid of “the curtain at the kitchen door” (by refusing to use any barrier acoustic filters),
we can pronounce that the task of “teleporting” the stereo system from the home’s “ living room” to the portable “kitchen” was, practically speaking, accomplished.
(which, as much as possible, DOES fully COMPLY WITH THE HOME AUDIO AXIOM #2);
- THE StereoPravda “SPearphone” IEMs’ “AXIOM” #3:
(A StereoPravda “SPearphone” IEMs’ design approach and/or an ear canal installation method and/or a special electronics solution which DO ALLOW, as much as possible, to fully COMPLY WITH THE HOME AUDIO AXIOM #3):
By positioning our IEMs at the intended spot of ear canal’s “second bend” (of course, if the appropriate ear canal anatomy allows for this) we’ve got all the reasons to believe that the “listener’s ears”-his tympanic membranes will “see” both the “key” drivers’ “naked” outlets, and the “secondary” and “auxiliary” drivers’ “sound tube” outlets directly in front of them (pic. 2).
(which, as much as possible, DOES fully COMPLY WITH THE HOME AUDIO AXIOM #3);
- THE StereoPravda “SPearphone” IEMs’ “AXIOM” #4:
(A StereoPravda “SPearphone” IEMs’ design approach and/or an ear canal installation method and/or a special electronics solution which DO ALLOW, as much as possible, to fully COMPLY WITH THE HOME AUDIO AXIOM #4):
By positioning all the main drivers within our IEMs “on a common axis” (pic.3) we create a device which fully matches the relevant physical parameters of a typical home loudspeaker.
(which, as much as possible, DOES fully COMPLY WITH THE HOME AUDIO AXIOM #4);
- THE StereoPravda “SPearphone” IEMs’ “AXIOM” #5:
(A StereoPravda “SPearphone” IEMs’ design approach and/or an ear canal installation method and/or a special electronics solution which DO ALLOW, as much as possible, to fully COMPLY WITH THE HOME AUDIO AXIOM #5):
By, again, using the “deep insertion” technique we provide a much “better” set of music listening conditions which include not only a “better” physical configuration of the “listening room”-the ear canal’s “operational” volume and its minimal size dimensions but also a “better” “loudspeaker’s”-the total IEMs’ driver configuration installation within the physical configuration of this listening space (pic. 2).
(which, as much as possible, DOES fully COMPLY WITH THE HOME AUDIO AXIOM #5);
- THE StereoPravda “SPearphone” IEMs’ “AXIOM” #6:
(A StereoPravda “SPearphone” IEMs’ design approach and/or an ear canal installation method and/or a special electronics solution which DO ALLOW, as much as possible, to fully COMPLY WITH THE HOME AUDIO AXIOM #6):
As the both of “the listener’s ears”-his tympanic membranes are already equidistant from correctly positioned “lodspeakers”-IEMs , in this department we don’t need to take any additional effort.
(a sigh of relief…)
(which DOES fully COMPLY WITH THE HOME AUDIO AXIOM #6);
- THE StereoPravda “SPearphone” IEMs’ “AXIOM” #7:
(A StereoPravda “SPearphone” IEMs’ design approach and/or an ear canal installation method and/or a special electronics solution which DO ALLOW, as much as possible, to fully COMPLY WITH THE HOME AUDIO AXIOM #7):
By, again, using our technique of “deep ear canal IEMs insertion” we create a set of conditions in the “primary listening room”-the ear canal’s “operational” volume for the intensity of the direct sound from the ”naked” “key ”drivers to significantly dominate not only over all the sound intensities of various acoustic distortions and reflections within the listening space, which would be much more significant in a case of a typical IEMs’ shallow ear canal insertion, but also to dominate over the intensities of acoustic inputs from the rest of the IEMs’ drivers.
Also, compared with “shallow insertion technique” of the vast majority of IEMs, our “deep insertion technique” results in much more benign “ear occlusion effect”, the latter facilitates decrease in middle ear’s “sound bone conduction”. In the above example, the sound “bone conduction” is a direct analogy of a “living room’s” stereo system’s sound “bleed through” to “the kitchen” via the separating wall.
As we are fully aware that only by placing our IEMs deeply inside an ear canal, close to its “second bend”, we can get as close as possible to “the near field” sonic experience, we see this “deep IEMs insertion” techniques as an indispensible idea for our ear monitors’ design approach.
(which, as much as possible, DOES fully COMPLY WITH THE HOME AUDIO AXIOM #7);
- THE StereoPravda “SPearphone” IEMs’ “AXIOM” #8:
(A StereoPravda “SPearphone” IEMs’ design approach and/or an ear canal installation method and/or a special electronics solution which DO ALLOW, as much as possible, to fully COMPLY WITH THE HOME AUDIO AXIOM #8):
By, again, using our “deep IEMs insertion technique” we can get as close as possible to place the “listener’s ears”-his tympanic membranes on the “direct” axis with all the “key” IEMs’ drivers (pic. 2).
The same is true about “the main sound propagation axis within the ear canal”: in our IEMs it’s on axis with the tympanic membrane.
(which, as much as possible, DOES fully COMPLY WITH THE HOME AUDIO AXIOM #8);
- THE StereoPravda “SPearphone” IEMs’ “AXIOM” #9:
(A StereoPravda “SPearphone” IEMs’ design approach and/or an ear canal installation method and/or a special electronics solution which DO ALLOW, as much as possible, to fully COMPLY WITH THE HOME AUDIO AXIOM #9):
By spending an effort on meticulous selection of the appropriate driver combinations, their loading solutions, by careful development of the drivers’ “sound tubes’” construction, and also, to name a few, by a concentrated effort to find the best “matching” resistors’ values and by using a proprietary design and a special installation procedure for our silicon tips we managed to get very close in delivering the amplitude-frequency curves for our IEMs which are very close to the “open ear” responses.
IEMs’ curves which comply with the latter ones are usually associated with an enhanced subjective perception of “sound coming outside of your head” (The similarity between the curves on pic.4 - the StereoPravda “SPearphone” SB-7’s frequency response and on pic. 5 - an “open ear” response - doesn’t prove anything, except that, according to the common reaction of those who auditioned our ear monitors, our IEMs do provide an enhanced feeling of “sound coming outside the head”).
pic. 6).
(which, as much as possible, DOES fully COMPLY WITH THE HOME AUDIO AXIOM #9);
- THE StereoPravda “SPearphone” IEMs’ “AXIOM” #10:
(A StereoPravda “SPearphone” IEMs’ design approach and/or an ear canal installation method and/or a special electronics solution which DO ALLOW, as much as possible, to fully COMPLY WITH THE HOME AUDIO AXIOM #10):
By spending an effort on meticulous selection of the appropriate driver combinations, their loading solutions and some rigorous process of choosing the best “matching” resistor values, we were able to achieve a “correct” amplitude-frequency response for our ear monitors without using any “passive” filtering networks or any wide band barrier acoustic filters.
That allowed us to completely get rid of the problems associated with the “passive” filtering networks’ IEMs applications, including the dramatic phase shifts (which is confirmed by the StereoPravda “SPearphone” SB-7’s phase response on the pic. 6).
(which, as much as possible, DOES fully COMPLY WITH THE HOME AUDIO AXIOM #10);
- THE StereoPravda “SPearphone” IEMs’ “AXIOM” #11:
(A StereoPravda “SPearphone” IEMs’ design approach and/or an ear canal installation method and/or a special electronics solution which DO ALLOW, as much as possible, to fully COMPLY WITH THE HOME AUDIO AXIOM #11):
By providing an opportunity to use our StereoPravda “SPearphone” SB-7A IEM model in full “two-way” “active” mode via using our dedicated portable “active” “two-way” StereoPravda DACCA unit we strive for the best portable audio quality available (pic. 7).
(which, as much as possible, DOES fully COMPLY WITH THE HOME AUDIO AXIOM #11);
- THE StereoPravda “SPearphone” IEMs’ “AXIOM” #12:
(A StereoPravda “SPearphone” IEMs’ design approach and/or an ear canal installation method and/or a special electronics solution which DO ALLOW, as much as possible, to fully COMPLY WITH THE HOME AUDIO AXIOM #12):
By reaching our long term partner and cable guru Chris Sommovigo for help we were able to get a special IEMs connecting cable that he developed and manufactures for us in Japan.
The sound quality was a top priority for the development of this cable, the other relevant aspects of its construction, such as its mechanical properties for portable use and “tear and wear” resistance were developed in strict accordance with highest sonic aspirations of home audio caliber (pic. 8).
The same way the “mini-jack” connector’s contact assembly used for the StereoPravda “SPearphone”-series IEMs was chosen purely on its sonic attributes. To use it with our custom cable and the “matching” resistors connected to the contact assembly, we had to develop not only a unique installation procedure but, also, we have to use a custom outer shell for the whole connector.
(which, as much as possible, DOES fully COMPLY WITH THE HOME AUDIO AXIOM #12).
What I’d like to suggest in the conclusion of this blog is to consider our ear monitors not as typical IEMs gradually improving typical aspects of typical IEMs solutions (with a legacy of their typical sound presentation), but as an attempt to realize the typical aspects of high performance home audio systems via a portable platform.
There is no doubt that it’s too early to talk about full “holosonic” effect in such a “static” audio set ups as ours, as for the full portable “3D” dynamic sound presentation you need not only a set of quite sophisticated individual calibrations and a “head tracker”, highly resolving head movements in space and time, but also you need some very powerful DSP-processing on board to implement fairly advanced real time algorithms’ software.
Nevertheless, the nearly full compliance of our ear monitors’ design approaches, their ear canal installation methods and full capabilities of our dedicated electronics with all the twelve of HOME AUDIO AXIOMS allows any user to perceive a fairly pronounced “an open ear” sound effect, which manifests itself in a “static” sound presentation outside the head at its perimeter.
Also, we’ve had a lot of opportunities to ascertain that, while being used with some advanced “3D-sound” technologies, such as Smyth-Research “Realizer”, compared with all the other IEMs and the headphones we’ve had at our disposal, our ear monitors demonstrated not only better overall sound quality but also more pronounced and realistic “three-dimensionality” of the sound presentation.
In the case of our StereoPravda “SPearphone” ear monitors combined compliance with all twelve of THE HOME AUDIO AXIOMS, has, obviously, been only the necessary condition for “passing the torch of “the old” (home) High End Audio to “the new” generation of the (portable) audiophiles”. (The sufficient one has been a determination to search for the best concrete solutions and their best implementations and also a little bit of luck while doing so).
To reach our goal of “passing the torch…” it would not have been enough just to seek compliance with only some of the axioms, not all of them.
It’s like in that saying: “to be a little free is like to be a little pregnant”, while developing an IEMs you should be aware that there are two discrete “states”.
Either one, realizing the currently established ideas about what constitutes high performance portable sound, or the other, realizing the currently established ideas about what constitutes great home High End Audio.
If we’d use the above analogy about the quality of sound coming to “the “portable” kitchen” from a stereo system playing in “the “home” living room”, then a partial compliance to each of “the states”, that is a partial compliance to each set of corresponding “axioms” (“home audio” ones vs “IEMs” ones) would have positioned the listener only somewhere in the middle of the “corridor” connecting “them”.
With a help of our products we’re trying to build a bridge between these two “states” which would allow us to effectively cross it from one state of “home audio” to another state of “portable one”.
In our case, completion of the building of that bridge in 12 steps of getting in full compliance with one HOME AUDIO AXIOM after another was like going through a twelve-step program to get rid of the addiction, in this case, an addiction to the currently dominating in Consumer Electronics Industry typical IEMs’ designs approaches and their ear canal installation methods (for the details of the latter, see my BLOG #8).
From that main idea of combined compliance with all the twelve AXIOMS OF HOME AUDIO we logically arrived at our own 12-steps solutions on:
- on utilization of “multi-driver” and” multi-way” Balanced-Armature driver arrays and on general StereoPravda “SPearphone” IEMs’ assembling techniques;
- on positioning our IEMs at the “second bend” of the ear canal;
- on a design and an installation procedure for our “universal” silicon tip (its shape, its angle, its controlled “leakage”, etc);
- on the “naked” (no “sound tubes”) “key” drivers selection and positioning;
- on placing all our IEMs’ drivers at the common axis, which is parallel to the ear canal’s “main sound propagation axis”;
- on the selection, the positioning and the loads of the “key” drivers, the “secondary” drivers and the “auxiliary” ones;
- on each driver array’s complement and design;
- on the total IEMs’ driver complement and design (special physical configuration of the total drivers combination to better conform the typical ear canal anatomy at its “second bend”, etc);
- on a complete refusal to use a set of conventional band-pass filters in our IEMs, and on a successful attempt to use no suchlike filters at all;
- on a complete refusal to use barrier acoustic filters in our IEMs;
- on designing an “active” “two-way” option for our IEMs to be used with our specially designed dedicated fully differential portable DAC/crossover/tone control/amplifier DACCA unit;
- on a custom connecting cable and on a selection of a “mini-jack” connector with the development of a special procedure to install all the necessary components inside it.
By the way, the only IEMs technology which is currently capable of providing us with ALL the necessary means to reach all of our goals is the “multi-driver” “multi-way” Balanced Armature driver technology.
None of the other IEMs technology, except for BA-one, (let alone “one way” headphone technologies of both the “closed”, and, especially, the “open” ones) can provide us with all the necessary means to meet all the combined requirements of THE HOME AUDIO AXIOMS stated above.
Why it is so I described in a lot of details in my BLOG #8.
Nevertheless, to grasp “the true essence” of our IEMs and to appreciate what they can deliver, you need to be aware that all the technical solutions stated above are not some isolated specs, but form a total interconnected combination of intent and decisions to try to arrive at a “point of bifurcation”, where a quantum leap in portable sound quality will happen.
That bifurcation point, in which “the true essence” of our products is realized, is the point where “the torch of home High End Audio’s old values is passed to the new generation of “portable” audiophiles”…
01.08.2016 // Author: (Bigmisha) // Number of views: 2962