the lower midrange 2 - in; speaker-systems, Passive & Active pre-amps: and a related look at the Audio-critique magazine pt 2. s-v.
For those who came directly to this page, you may wish to read this article from the beginning, at Part 1.
The LOWER-MIDRANGE and The STATUS-QUO: Here, we continue our examination of issues having to do with the lower-midrange, from the perspective of our examination of the related issues brought to light by the Audio-Critique's recent discoveries. I should point out that the Audio Critique's (previous?) views on some of the issues, here - passive pre-amps, speaker-systems, and the lower-midrange - are more representative of the status-quo than mine are, here at WAJ on AUDIO S-V. In this scenario I'm the radical rebel more akin to the 'lone wolf howling in the wilderness' (or one of 'the very few').
The 'Critique's recent discovery of the difference, in lower-midrange body and detail, or 'substance', between the popular single pair, and double-stacked mini-monitor/subs, is consistent with the arguments we've been positing for some time now, on the subject.
The same applies to its discovery of the similar lower-midrange deficiency in a passive pre-amp, vs an active pre-amp's superior reproduction of that region.
All serious audiophiles should, perhaps, take note of the 'Critique's recent experiences, especially with regard to the arguments, here. The arguments espoused here at WAJ on AUDIO S-V are fundamental to the achievement of lifelike sonic realism, for those who're interested. And the recent discoveries of the 'Critique are, perhaps, additional evidence of the veracity of these arguments. The Audio Critique's recent discoveries, exactly, corroborate some of the unique and unpopular points that have consistently been made here since WAJ on AUDIO S-V's very beginning. (That is; the lack of lower-midrange prowess in the vast majority of popular speakers, and also in passive pre-amps, causing a debilitating dearth of realism in systems which use them). Other arguments regarding the route to realistic reproduction (for example; the importance of the lower-mids, and the critical need for 'adequate' speaker-driver surface-area, among other factors, in facilitating the realism it engenders) have also been, inadvertently, substantiated by the 'Critique's accounts of its recent experiences.
Perhaps there's something to what we've been saying, after all. Even if you disagree with some aspects of these arguments, they perhaps warrant contemplation nonetheless.
I (along with 'the very few', as I've recently discovered) believe that most popular speaker-systems are fundamentally flawed, with a bright treble, thin midrange (bereft of realistic lower-mids) and inadequate dynamism. I believe there's too much of a focus on the resolution of detail in favored regions (which a thin midrange does facilitate) at the expense of a realistic lower-midrange capable of replicating the robustness of the tones of live acoustic instruments operating in this region, not to mention the wealth of other detail that is also lost - resonances, minute detail, and the fade of notes, for instance. Single 5" - 7" mid/woofers crossed-over to subwoofers at, or below, 160hz simply do not possess the surface-area necessary to achieve realism in the low-mids region around 200-500hz, or there about, especially at realistic volume levels.
And surface-area isn't the only issue: From experience, in extensive experimentation over the years, with various audio-systems (including my former 'semi' pro-sound rig) I've come to the realization that very, very few drivers of even 'adequate' size (above 10") are even competent in this region. Judging from the very few speakers I've found with this competence, my only conclusion must be that drivers (and their x-overs) must be imbued with this capability on the drawing-board (whether by accident, or by deliberate design). Perhaps designers such as the likes of the late Messrs Henry Kloss, Rudy Bozak, Guy R. Fontaine/Ronald Rackman, etc. (all exponents of lower-midrange body - or, as they would've called it; 'good tone' - in their designs) could/should have given modern designers a few pointers along those lines before departing for that great concert-hall up yonder. Not that modern designers (bent on their charted course) would've been interested, anyway.
Thanks to close-mic recording techniques, allegedly flawed (with a rising top-end) moving-coil cartridges, and speakers with the fore-mentioned characteristics (or faults) audiophiles are exposed to more detail (in limited regions) than is ever apparent in normal seating positions at a live acoustic musical concert performance.
Some audiophiles will go to great lengths to extract the very last scintilla of 'detail' and 'air', especially in the middle-mid to higher frequencies, even though tone and detail are also being lost in other regions. (Such audiophiles are amongst the most avid of 'pre-amp less'/passive advocates, incidentally). With such components and systems, realism is, at best, a fleeting illusion, in my view, with a tonal balance that much askew. Yet there are many (the majority?) who seem to love this type of sound, and systems, where an abundance of (limited) detail is king. I'm not saying that they're wrong - this is what they like - no quarrel there. And, yes, I do respect these preferences, and even aspects of the sound of some of such systems. But preferences are just that; preferences. And it should also be highlighted for the unwary that such preferences, practices, and sonic characteristics, run counter to the requirements for sonic realism. Sonic realism does not cater to tastes and preferences!
An aspect of the popular trend today is to ignore the lower-mids completely (due mainly to intrinsic shortcomings in small-coned drivers currently favored). Perhaps aficionados of the resulting type of sound need to be reminded that the low-midrange is an integral part of the audio-spectrum - just as important as the rest of the midrange, and more important than bass and treble. (Think about it in a context which recognizes the WHOLE midrange as THE most important region in nature and in music). Slighting or ignoring this region (in favor of highlighting other regions, and/or because of shortcomings in small-coned drivers) can never result in accurate and lifelike reproduction - sonic-realism. This partially explains the deplorable performance of modern small-coned speakers today, when it comes to replicating a live performance.
Neither does the reproduction of sonic realism, generally, cater to any other factor not having, directly, to do with the strict requirements for the achievement of sonic realism. With the use of dynamic/cone drivers/enclosures, for instance, the laws of physics dictate that the reproduction of true sonic realism includes the requirement of a large driver (or several smaller ones - all with innate lower-mid capabilities) and a large enclosure, to facilitate the requisite dynamism and lower-midrange tonalities necessary for realism. [This is the logical interpretation of those laws - and the evidence substantiates this theory].
Indeed, the theory has long been proven - again and again - this is what once prevailed, quite successfully, with regard to sonic realism: It's, certainly no accident that two of the remaining best 50-odd year-old designs, Tannoy and Klipschorn, are among the most widely-acclaimed for their lifelike realism, TODAY. Lifelike-Realism; which cannot be approached, let alone surpassed, by most of today's 'state of the art', mini-monitor-derived, 'cutting-edge' speaker-systems, TODAY. It is significant that both designs generate the lower-mids (and dynamism) thru the use of efficient & large mid-woofers, operating from large enclosures. This remains the state of the art method of reproducing a lifelike lower-midrange, without which the reproduction of music can never be truly realistic. Anything less is, therefore, a compromise, and must also be recognized as DEFICIENT, in any quest for the ultimate in sound-reproduction!.
Interestingly, I've never encountered any single small driver which can REALISTICALLY replicate the lower-midrange tones, resonances, overtones, power, room-filling bloom, and expansion of the notes of a piano, for just one example - none whatsoever. (Don't be confused by the piano's bass tones from a subwoofer, for instance, listen to a mini-monitor by itself, and concentrate on the lower-mids. But ideally, the simultaneous, or alternate, playing of those lower-midrange notes on the actual piano, or any other relevant instrument, will erase any doubts).
However this is not surprising, and only logical, when one really examines the situation: The lower-midrange resides next-door to bass, in the audio-spectrum, and several of the prerequisites for realistic bass also apply to the lower-midrange. Therefore, for the same reasons a mini-monitor cannot supply realistic bass, it cannot supply realistic lower-mids, especially at realistic levels. Simple logic applies. Let's not continue to fool ourselves. Any route, other than the ideal, as prescribed by physics, is doomed to be compromised in the resulting sonics - from significantly, to severely - according to the laws of physics.
Yet, since the 1970's, this minor tributary of the hifi discipline, mini-monitors (with sub-woofers later added) has grown to become the main stream (a river of tears, really) with a view to facilitating; space-constraints, aesthetics, convenience, tastes & preferences, W.A.F., and every other factor not having to do with the achievement of sonic realism. Nevertheless, they excelled at middle-mid/high-frequency detail-resolution and stereo dispersion. As would be expected, though (according to the laws of physics) such systems, generally, are severely compromised in both dynamism AND tonality (with an inherent lack of lower-midrange capability) and, therefore, severely compromised in their potential for overall sonic realism.
But because of the wide acceptance of these convenient but compromised systems, industry and the mainstream audio-press (in influencing the status-quo) have long opted to play upon the mini-monitor's strengths in touting these systems, and fooling the general public with the notion that these are the best things since God invented the female of our specie. In accordance with this, and in the face of the mini-monitor's ineptitude at overall sonic realism, industry and the press (with the compliance of the status-quo) cunningly opted to tout 'detail-resolution' (at middle-mid to high frequencies) and 'stereophonic imaging' (the mini-monitor's strengths) as the most desirable attributes in audio systems. Sonic realism has long been relegated to an after-thought. And, dynamism?
.The lower-midrange (which mini-monitors cannot reproduce) no doubt motivated by; 'The fox can't get the grape, so he says it's sour' paradigm, has long been disparaged as an undesirable 'warm', 'dark', and 'distorted' monster to be eschewed at all costs or, at best, tolerated, as an option, in very small measures, according to taste (as if realism can be adjustable, after the fact of the recording of it) contrary to the dictates of nature, and contrary to the requirements for lifelike sonic realism.
Speaker-systems other than mini-monitors have long been deliberately tuned to emulate the mini-monitor's so-called 'neutral' (read; thin) midrange characteristics - after all, this type of sound is the current fad. Other components have long been rated on their ability to cater to the mini-monitor's strengths (passive pre-amps, for instance). Thanks to the status-quo, 'detail-resolution' has long been seated on the throne of the high-end realm. Sonic-realism, and its indispensable first-ministers (lower-midrange prowess, and dynamism-esquire) have long been deposed, and condemned to the depths of the dungeon.
And, yet, we wonder why our systems can't replicate reality! (Others of us fool ourselves into thinking that they do. And, still, others really don't care about realism, just as long as the system caters to - you guessed it - tastes & preferences. Not that there is anything wrong with that, if the system pleases the listener. But to claim that systems with the-above mini-monitor characteristics seriously approach overall realism would be an exercise in pure fantasy, and it is).`
Of course, such compromised systems do have relevance in the majority of applications, where the ultimate realism in reproduction is not sought. And their achievements are commendable (some are especially remarkable) in that context. But most have no business presenting themselves as viable options in any real quest for the ultimate in lifelike and truly realistic audio-reproduction. Nonetheless, this is what the status-quo has long purported to be the 'ultimate' - with (limited) detail-resolution and imaging being their greatest assets, aided by bass and prominent trebles and, of course, thin...sorry... 'neutral' middle-mids - even though, with such systems, true sonic realism is doomed to remain a pipe-dream.
For those interested in SONIC-REALISM, perhaps a radical revision of the status-quo is in order. As it stands, low-level detail-resolution (at higher frequencies) is at the top of the order, and that's fine for (limited) analytics. But for REALISM, I believe tonality (inclusive of the crucial, and currently missing, lower-mids) high-efficiency/dynamism (also missing in most) and low-level detail-resolution (in that order) should be the order of priority in speakers, particularly, and in general system-building.
THE BIG PICTURE: I believe the overall 'Big-Picture' is much more important than its minute details. Fix the 'Big-Picture' (which surely needs fixing if the lower-mids and/or dynamism are missing, or significantly compromised) and THEN tend to the minor details. A picture of an object cannot be a truly accurate and realistic representation of that object if major parts are missing from that picture of the original object. Minute details cannot compensate for, or disguise, the lack of major parts of that picture. This picture may, in some ways, be attractive to many but, with missing parts (dynamism and lower-midrange) it cannot be a realistic depiction of the whole original object (live music).
As to the core-differences between the Audio Critique and WAJ on Audio S-V: Judging by what is stressed at both sites; the Audio Critique is, perhaps the Mecca of Detail-Resolution and Dynamism. (Despite the prominence of detail-resolution, even this is outstanding, in my opinion, since most mags, and others, do not ascribe this high level of importance to high-efficiency/dynamism. And even if this is may have been primarily inspired by compatibility with low-powered S.E.T. amps, the advocacy of efficiency/dynamism is commendable, nonetheless).
WAJ on AUDIO S-V is, perhaps the Mecca of Lower-Midrange Tonality, Dynamism, and Overall Realism. Since we need not focus on elements which are already there in most good systems (eg; detail-resolution, middle-midrange tonality/accuracy, etc.) my focus is on those crucial elements which are missing. The missing elements which combine to complete the whole - overall realism - the ultimate goal. These are the elements which, in my experience, overall realism cannot be truly achieved without!
And, no; WAJ on AUDIO S-V does not advocate an overly 'warm' midrange - just the addition of the lower-mids currently ABSENT from most popular speakers, and many components. Regarding my reference: My own system does not 'color' or falsely emphasize the lower-mids (or any other region). It is, indeed, just as lean (and bereft of detail) at lower-mids, when operated pre-amp less, as every other 'neutral' system which lacks the capacity for lower-midrange prowess. And that lower-midrange prowess is only displayed when my active pre-amp is inserted. Neither can this pre-amp be accused of being a 'colorful' tube-unit emphasizing the lower-mids. This pre-amp is the solid-state ARC LS3, reputed to be one of the most neutral units on the planet, it's also rated amongst the 'best' (re; Stereophile, AudioCritic, etc.) for whatever that is worth. (It's also switch able to the passive-mode, bye the way, for whatever that is, also, worth - slightly more treble clarity, and a whole lot less lower-midrange body, detail, and overall realism - no thanks). My 'passive pre-amp' assessments, however, are mainly based upon years of pre-amp less system operation, prior to the acquisition of this pre-amp, though several active/passive/pre-amp less comparisons, over the years since then, have only served to strengthen my resolve.
PASSIVES' SONICS UNIVERSALLY RECOGNIZED TO BE 'LESS-HEFTY' THAN ACTIVES: So, the question is: Which is right? There's also the question of how universally wide-spread the shortcomings of the various passive pre-amps really are. After all, couldn't there be a few which are just as good as active pre-amps, in the latter's areas of strength? .
Well, the short answer to that is; NO! Any lingering doubts I may have had, about the universality of passive pre-amps' deficiency, were completely dispelled after conducting my own 'mini-surveys', one of which is linked below. All indications are that the passive pre-amp's lower-midrange deficiency is innate, intrinsic, absolute, all-pervasive and, indeed, 'universal'. There are no exceptions. (However, the majority don't see this fault as a fault, for various reasons). Despite the fact that many audiophiles, with 'state of the art' systems, are enamored by the passive pre, it is what it is - a severely flawed system. Flawed in the context of the pursuit of absolute realism - as the similarly state of the art system of the Audio Critique, and those recent experiences (discussed in Part 1) bear witness to. In addition to WAJ on AUDIO S-V's own (active ARC LS3 vs Passive/Pre-amp less review) the similar reports of others such as; Stereo-Mojo and the Audio Critique (even if 'slightly' less emphatic) only serve to drive more nails into the passive's coffin, which is now sealed, as far as I'm concerned.
I'm not much given to theory and conjecture, myself. Truth is; no-one has all the answers - many don't even recognize the problem (and, with the majority of speakers, this is understandable). But if I were to offer a possible explanation, I'd suggest that the passive system is innately parasitic and 'lossy'. And that these losses can never be compensated, in the passive realm. A purely passive system, by its very nature, will always be ‘lossy’ and, therefore, will always be deficient, due to the magnitude of the consequences of even the slightest losses at such miniscule signal-levels. Such losses may be tolerable in passive speaker x-overs, for example, where the strength of the signal is much more significant. But at the signal-level at which input-sources operate, such losses are, perhaps, catastrophic. The obvious solution would be a system supplying some amount of gain, thus obviating those losses. But we've had that for a very long time; The Active Pre-Amplifier, or Line-Stage.
To be fair to those inclined toward the passive, I'll add that transformer-based volume controls (TVC passives) are reputed, by some, to be the best. They're reputed to circumvent some of the issues presented by resistor-based passive pre-amps. (Similar claims are made for Light Dependent Resistor, or LDR, passives). A review of one of the very best TVCs (from Music First Audio) is here. However, though the reviewer claims it to be not as thin and bleached as most other passives, comparisons with an active pre still reveal the active to be more hefty in 'body'. This reviewer opines that this may be due to an 'enhancement' in the active (see below, for more on this perception, vis a vis the stark reality). And though I cannot speak to the situation with his particular (tubed) active pre, I can confidently suggest that my own solid-state active pre is not so 'enhanced' - even if only based on its stellar reputation for neutrality. Yet it too displays more 'body' than the passives it's been compared to, over the years. No TVC has yet been tried, though - forgive me if I'm not too optimistic on that front, based on all I've gleaned, even from owners of TVCs, LDRs, and all other types, including buffered passives.
[Passives have caused an increase in the awareness of the need for (and the availability of) excellent volume controls, though. I believe the best of both worlds is; a very good (neutral - not 'colored') active pre-amp, modified with one of the best of these controls - a TVC, for instance - potentially eliciting the slightly increased clarity and H-F detail of a passive, combined with the realistic 'body', and lower-mids detail, of an active. My own pre may be so modified, in the not too distant future - watch-out for that report, which will be forthcoming, if time permits, and if further investigations, indeed, warrant such a mod.] :
For those who doubt that there is a significant difference between active and passive pre-amps, at lower-mids, perhaps a thread I started (here) at the Audio-Asylum may be helpful (ie; in addition to the evidence presented here). Though not a large sample of responses, the results may prove enlightening, with the most compelling evidence against the passive pre-amp coming from a few of its own advocates: Understandably, some active advocates recognized the active pre-amps' superiority at the lower-mids, and some just preferred its sound without putting a finger on the reason why. And, indeed, others of the respondents expressed a preference for the slightly better treble clarity of passives but, surprisingly, even some amongst those admitted to the fuller lower-mid tones of actives, though a few tried to pass this off as a 'coloration', 'flavoring', or 'enhancement'. (This is the general consensus among passive advocates, in my wider experience: Amongst those who're equipped to even discern a difference, most agree that actives are 'fuller-toned' than passives, but they also feel this is just a pleasant 'coloration', and that actives are 'enhanced' in this region, somehow).
So, then, there's not much of a dispute as to the nature of the differences between passives and actives, in the lower-midrange. The dispute concerns; which is more accurate, in this region - easily settled by a comparison with live music. But I'd wager; few to none, from either side of the argument, have actually done this).
In the above 'survey', one or two passive advocates (no less) even expressed the VERY IMPORTANT POINT that actives are better at the 'trailing-edges' and at the 'fade of notes'.
This superiority, of actives, with the 'trailing-edges and fade of notes', combined with the 'fuller-toned' lower-midrange, is extremely highly significant, in my experience, as this combination of factors is what (contrary to the capabilities with passives) COMPLETES musical notes, facilitates the reproduction of lifelike instrumental resonances, affords access to minute detail in this region, and brings vastly improved levels of authenticity and realism to the reproduction of music IN THOSE RARE SYSTEMS WHICH ARE FULLY CAPABLE AT THE LOWER-MIDS.
[I must warn you, though, that this thread was contaminated by two main antagonists (aided by two others) who seem to seek to fill empty lives by prowling the threads seeking to provoke arguments which, most times, have nothing to do with the premise of the thread - it gets ugly (and, no, I weren't no shrinkin' violet neither). Because of the confusion this may have caused, a summary of the relevant responses was provided near the end of that long thread. I hope it is of some benefit].
Nevertheless, just as when I introduced a similar thread on the problem of a lack of lower-midrange capability in most speakers; with this similar issue in passive pre-amps, I was again surprised to find I was introducing a topic on a 'problem' that many people had not noticed as being a problem. I see this as another indictment of the status-quo and, perhaps, a reflection on the manufacturers and users of popular speaker-systems, which are compared to each other, instead of being compared to live music. The rationale seems to be, for a typical example; "Speaker 'X' is 'better' than speaker 'Y' - more delicate treble-detail, more 'air', more 'holographic' imaging - therefore, speaker 'X' is the 'cat's pajamas'". Not quite! Not if neither 'X' nor 'Y' can properly highlight the differences between active and passive pre-amps, let alone replicate the actual robust sound of live music - as is, more often than not, apparent - based on the evidence. [Another thread I introduced, on the subject of passives, is at Audiogon, here - also summarized near the end.]
As to the allegations of active pre-amps' 'enhancements' and 'colorations' (not to mention similar allegations concerning amps and speakers capable of lower-midrange prowess) I'm lucky to be able to directly compare my active pre-amp, customized speakers, the rest of my components, and the complete audio-system, against live music, in real-time, from time to time. This is the closest any system of mine has ever been to the sound of those live instruments - eerily close. [This is something I could never have said concerning a previous so-called 'state of the art' system, of mine, that was very similar in basic characteristics to the vast majority today - deficient lower-mids, and all. Impressive by itself in several ways, yes, but a devastating disappointment, directly compared to those live instruments.] And the lower-midrange performance is among the main elements that take this current system so close that it's possible to mistake it for the real thing, at times.
So for those who like to shout 'colorations' and 'enhancements' at the mere mention of the lower-midrange, my suggestion is; measure it against the REAL THING!
I say again; to solve the 'mystery' as to which is accurate at the lower-mids (passives or actives) compare both to live music, and concentrate on the low-mids - it's that simple - no argument necessary!
Note: The status-quo has disregarded, and discriminated against, the lower-mids for a very long time. This is blatantly evident in its enthusiastic endorsement of its ultimate standard; 'no pre-amp' or passive 'pre-amplification' (which is proven to be lacking in this region, even by some of its own advocates). And this is also evident in its endorsement its 'state of the art' standard of popular high-end speakers; the mini-monitor/(sub)woofer combo, which is similarly lacking (a fact bolstered by the evidence that most cannot properly demonstrate this deficiency of 'passives', or the advantage of 'actives'). Therefore, on the issue of the lower-midrange, the status-quo must be WRONG!
With all else being equal (dynamics, detail-resolution, etc.) the re-introduction of the lower-mids, to music-reproduction, facilitates the re-introduction of REALISM to the strains of music - as nature prescribes it. The lower-midrange is, in fact, a construct of nature (and of music, consequently) not a 'warm'/'dark' anachronism to be avoided, as many audiophiles have been groomed to believe, by the status quo. The lower-midrange is, indeed, an integral and critical component of music, the reproduction of which CANNOT be truly realistic without it - contrary to the dictates of the status-quo!
SOME of the RARE SPEAKERS with LIFELIKE REALISM at LOWER-MIDS: From my own experience, I'm completely sure that the use, thru lower-mids, of a mini-monitor's mid/woofer (such as those utilized by most popular speakers, including floor-standers, and D'Appolito'd in monolithic, 'state of the art', floor-to-ceiling towers) is inadequate in any effort to fully replicate the volume, realism, and visceral impact of the lower midrange tones of certain instruments with any semblance of authenticity. Therefore, a mini-monitor, crossed-over to its (sub) woofer below 200hz, would also not be able to fully demonstrate the vast advantage the best active pre-amps hold over the passive mode of operation (as has now been discovered by the Audio Critique) in this lower-midrange region, where passives simply do not operate. In fact, the passive/pre-amp less mode simply ignores most of the lower-midrange as if it doesn't exist and, in that sense, it's a perfect match for most popular speakers which do exactly the same.
I'll go further, for the sake of my readers: In my opinion, the reason for the popularity/credibility of the passive/pre-amp less mode of operation is that its deficiency isn't generally noticed because most popular speaker-systems are similarly compromised. Some passive fans believe that since the passive's high-frequency reproduction is so accurate (and it really is) in the best examples, then the thin (near non-existent) lower-midrange they produce must also be accurate. It is not - and this can be proven! But this is also, partly, why they also believe the active's fuller lower-mids reproduction is 'enhanced' or 'colored' - they are wrong, of course - the best are not. And this can also be proven! Many are also motivated by the compelling, but superficial, logic of purity, simplicity, and accuracy to the source (as I was, once). However, because of flaws intrinsic to the passive system (some of which were mentioned earlier) the passive system fails to fully deliver on its promise. (I honestly wish it did - this would render the relatively high cost of an active pre-amp un-necessary - imagine the savings this would induce).
The proof of the active's superiority (and the deficiency of the passive pre-amp, and of most popular speakers) is simple: As asserted previously, a comparison with the actual sound of live acoustic instruments dispels any doubts. But very few have ever actually done such a comparison, so the arguments rage on, fueled by blissful ignorance and, of course, by tastes and preferences.
The truth is; no active pre-amp on the planet is as clear at high-mid to high-frequencies - the best are very close, though (very few, like Coincident's Statement, nullify the passive's slight advantage, almost, completely). Nonetheless, the truth is, also, that the passive/pre-amp less mode of operation is very SEVERELY COMPROMISED in its (non-) performance at the lower-midrange and, therefore, severely compromised in its potential for overall realism. But since most popular speakers are lacking in exactly the same way, the deficiency with passive/pre-amp less is unlikely to be noticed in such a system. Additionally, comparing pre-amp less with even some of the best active pre-amps in such a system will, nearly always, result in favor of the slightly clearer high-mid/high-frequency presentation of pre-amp less since the speakers are unable to display the considerable advantage of the active pre-amp at the lower-midrange, and the consequent vast increase in realism.
This explains why 'expert' audiophiles (representative of 'the status-quo') using any of the majority of popular speakers will have coined the phrase; ' the best pre-amp is no pre-amp' - it's a fallacy, in reality - only "true" with the use of the majority of similarly compromised speakers. Significantly compromised reproduction is the inevitable result.
On the other hand, however, the same comparison using one of the rare speaker-systems which are truly competent at the lower-mids will easily reveal several of the better active pre-amps to be ridiculously superior, as the previously constricted lower-midrange is now unleashed to bring much more realism to the reproduction. The very slightly less clarity of the higher frequencies (not even a noticeable factor unless directly compared to pre-amp less) is of little consequence in the context of the 'big picture' of the vastly enhanced OVERALL REALISM. Compared in this system, pre-amp less' presentation may still be slightly clearer in the higher frequencies but, more importantly, the critical lower-mids will also now be shown to be conspicuously and starkly MISSING, and the overall reproduction far less realistic, compared to that of the active pre. This I guarantee, from my own experience previously and, now, that of a few others.
Nevertheless, since most speakers are as compromised as they are, pre-amp less is still relevant, only in that limited context. (It's the ideal mode for those seeking the very best in higher-frequency clarity, AND NOT MUCH ELSE, for instance). But, seriously, those who find themselves with amps (quite a few) and speakers (the vast majority) which are just as deficient, and cannot properly display the advantages of a good active pre-amp, are well advised to go 'pre-amp less', to make the 'best' of a 'non-optimal' situation. [No offence meant, really, but these are my opinions (based on my experience in the matter, and that of others) and I find it difficult to be less than forthright in expressing them].
If however, an audiophile seeks the most realistic overall reproduction possible, then one is best advised to seek one of the better ACTIVE pre-amps; Coincident, Dodd, Doge, Dude, etc. (new). Or one similar to those (vintage) units cited elsewhere in this article (preferably tubed, or 'tube-like' solid-state, and post-80's vintage, generally) a good amp (ditto) AND just as importantly, but most difficult to find; a very good speaker-system that is highly efficient, realistically dynamic, AND truly competent at the LOWER-MIDRANGE - you will not regret it. Relish the realism.
In so far as those 'difficult-to-find' speakers are concerned: Virtually any Tannoy from the 'Prestige' line would be viable for such use, though I'd tend to prefer those at, or near, the top of the line. (Here are links to the reviews of two examples; Westminster Royal, and Churchill). Legacy Whispers could be investigated. (A review of the Whispers is here, incorporating another rare view - from one of 'the precious few' - on the lack of the lower-mids, and dynamism, in most modern speakers). Page 6 of a recently discovered review of the $43k Legacy Helix is linked here, highlighting; 'What a Huge Speaker Brings to the Party' (Note that the Helix, and the Whisper, utilize more cone-surface area, for the lower-mids, than virtually all other modern 'state of the art' cone-driven contenders. There are very few exceptions. However, you don't need to spend $43k, or more, for 'huge' (lower-midrange) cone-surface area, and the benefits there-of: The $4k-odd Klipschorn could also be utilized, if its middle/upper-midrange horn-characteristics prove tolerable - substitution of the mid/treble horns, for other horn-types, could also alleviate these concerns. And though I believe it's bettered by one or two others in lower-midrange tonality, it's better than most current designs in that region, and STILL one of the handful of THE MOST realistic reproducers of sound ever made - devastatingly dynamic and ludicrously lifelike. The Klipschorn is totally awesome - Westminster too - I haven't heard the Helix, but if it's better than the Whisper, then it's a force to contend with since the Whisper, itself, is no pretender.
[Edit: In the interest of shortening this article, and also for the purpose of providing a more convenient source for reference, the bulk of this list of capable speakers has been removed from here, expanded, and incorporated into a separate article entitled; 'The Ultimate Speakers Are Within Reach'.]