JBL L100 Classic Bookshelf Loudspeaker Review - Modern Take on a Classic (2024)

JBL L100 Classic Introduction

Alot of things have changed in the home audio industry over the last fiftyyears. Advances in acoustic engineering, measurement, and manufacturing havepropelled loudspeaker design to levels of performance that would have beenunthinkable fifty years ago. The science of what comprises a good sound and howto achieve it was still relatively crude back then, although it was much closerto modern standards than the dawn of sound reproduction in the late nineteenthcentury. Nonetheless, even though audio equipment has improved tremendouslyover the past fifty years in both performance and affordability, it is muchless popular than it once was. Fifty years ago was smack dab in the middle ofthe “golden age” of hi-fi (read our article: When Was the “Golden Age” of Audio Hifi?). High-fidelity soundsystems were far more prevalent in those days, and many middle-class householdshad some kind of furniture-sized stereo system. In the midst of the audio hobbyat its prime came the JBL L100 loudspeakers. JBL had already had some classicloudspeakers before then, for both professional and consumer applications, butin 1970 JBL launched the L100 Century. It would turn out to be THE JBL speaker,their most successful speaker ever released. It was so successful that it made#7 in our list of the top ten most influential loudspeakers over the last50 years, and became one of thebest-selling loudspeakers of the 1970s.

Whatmade its popularity all the more impressive was that it was not a cheaploudspeaker in its day ($273 ea.). Adjusted for inflation, throughout the ’70sthe pricing averaged about $1,500 to $2k each in today’s money (time of thiswriting: February 2021, just in case that sudden inflation hits after thepublishing of this article). Few middle-class households would spend that kindof money on loudspeakers these days. Yet the L100 was so popular that it wouldbe the choice of speaker to be used in Maxell’s iconic “Blown Away” ads in the1980s which enhanced its reputation even more. Many people loved the soundand the distinctive look of the L100 speakers, and they were willing to pay forit. The L100s were more responsible for therise of the more aggressive “West Coast Sound” than any other speaker,in contrast to the more polite “East Coast Sound” from manufacturers such asAcoustic Research, Advent, and KLH. It was a powerfulspeaker with punchy bass but wasn’t gigantically-sized among floor-standingspeakers of its day. Furthermore, it has a unique look thanks to the “Quadrex”foam grille which made it stand out among typical fabric stretch-wrappedgrilles. You can read more about the history of the development of the L100s in the article: Development of an Industry Standard - JBL 4310

Sohere we are, fifty years later, and JBL has relaunched the L100s. It’s not thesame exact design, of course, and JBL has modernized the drivers, crossover,and elements of the cabinet, so while it might have a vintage look, it shouldn’thave a vintage sound. The pricing is in line with the original as well, whenadjusted for inflation. It’s a tribute to the classic original, in fact, JBLcalls this new one the “L100 Classic”. This is the speaker that we arereviewing today. While the L100 Classic is a speaker loaded with history, I amnot going to evaluate it as though it were a historical artifact. The originalwas a speaker that was popular before my time; in fact, it was discontinued inthe year I was born, so I don’t have the nostalgia for it that its design andmarketing is partly banking on. How good is the JBL L100 Classic as a modernhigh-fidelity loudspeaker? That is the question we will attempt to answer intoday’s review.

Appearance

The appearance of the L100 Classics is very mucha matter of taste, but probably anyone reading this has already come to aconclusion about their vintage aesthetic one way or the other. You either love‘em or hate ‘em, and few people will be on the fence about them. Personally, Ilike them, but that could be due to the fact that most speakers I review end upbeing some variety of a black box and so I am far more receptive to somethingthat breaks out of that mold. Were it not for the Quadrex foam grille, theywould simply look like older speakers to an undiscerning eye and notparticularly attractive or notable. The Quadrex grille gives them a style thatsome may find gaudy but I think it is fun and just a bit flamboyant. They aredefinitely a better fit in the more colorful interior decors of the ’70s thantoday’s dour modernist interiors. These are speakers with personality thatbelong in a home with personality rather than the mausoleums that pass forliving rooms these days. The L100 Classic is available in a black Quadrexgrille for a tamer look, but what’s the point of that for speakers like thesewhich are supposed to be splashy?

Oneaspect that will draw attention is how the size and shape will determineplacement. JBL calls these bookshelf speakers, but that laughably strains thelabel “bookshelf speaker” (However, in the day of the original L100, many bookshelf speakers werethis size). No ordinary bookshelf could fit thesespeakers, nor would you want to place them in a bookshelf anyway since that isan acoustically compromised location. They are not quite tall enough to befloor-standing speakers unless you have a low seating position like the Maxwellad guy, but they are awfully big for stand-mount speakers. JBL provides anangled stand for them at an extra cost, and JBL’s stands sort of split the difference between stand-mount and floor-standing. Ithink JBL’s stand is the best approach aesthetically, but a problem with itfrom a sound performance standpoint is that most speakers sound best when thetweeter is aimed at the listener’s ear level, and these stands make distance afactor in achieving the best listening position where it wouldn’t if thespeakers were placed at a level angle.

TheL100 Classics have a real wood walnut veneer for side-paneling, and a matteblack front and back panel. Without the grille, the front baffle looks almosttotally utilitarian, with a big white woofer mounted under a black midrange, alarge port, and a tweeter with a silver dome. There is also a small panel witha couple of knobs for adjusting tonality. This functional appearance is adeliberate stylistic choice, and if you like vintage speaker design, it doeshave a fashionably old-school look. This look is a design pretension though,and speakers aren’t made like this anymore for several reasons, only one ofwhich being that consumers started drifting toward smaller and narrowerspeakers over the years.

Design Analysis

Weshould start our analysis of the L100 Classic’s design by saying it only looks old-school. This is a retroloudspeaker in looks alone, and under the hood, it is all modern loudspeakertechnology. Let’s start our analysis of them at the top with the tweeter. JBLuses a 1” titanium dome tweeter mounted in a shallow waveguide with an acousticlens. The motor for the tweeter is quite substantial and uses a hefty 3 ⅛”diameter ferrite magnet instead of neodymium like so many other tweeters. Whileiron ferrite magnets need to be a lot more massive to equal neodymium’smagnetic flux, their advantage is that there the much greater volume andsurface area gives them a greater ability to soak up and transfer heat, so themotor will be much less affected by thermal compression. The waveguide andacoustic lens should enable the tweeter to hold a more consistent dispersionpattern throughout its frequency band.

Movingdown to the midrange driver, we have a 5.25” polymer-coated pulp cone. It hasits own sealed compartment that was strongly adhered to the driver frame so Iwasn’t able to get a look at the motor. The isolation from the internal airvolume of the speaker is a good idea because pressure waves from the bass drivercan interfere with the motion of the midrange cone otherwise and lead todistortion. The bass driver itself is a formidable piece with a 12” pure pulpcone held in place by a large cast-aluminum frame and a 3” diameter voice coil.The hefty magnet section consists of two rings adding up to a 1 ⅛” stack with a7” diameter. This beefy bass driver weighs over 21 lbs., and in order to mountthe speaker on my testing platform when I measured it, I removed the bassdriver to lift the cabinet onto the platform since it would have beentortuously heavy to do otherwise. A driver like this is doubtlessly capable ofsome pretty high SPLs.

The JBL L100 Classic 12" Bass Driver with Cast Frame & Massive Motor Structure and Vented Pole Piece

Thecrossover network is a pretty serious piece, and I counted 15 components on theboard with some very large electrolytic and poly film capacitors, resistors,air-core inductors, and an iron core inductor. The crossover frequencies are450Hz and 3.5kHz using and use 2nd order filters except for thehigh-pass filter on the tweeter which uses a 3rd order slope. That is arelatively wide range for a midrange driver, and the advantage of that is therewon’t be any crossover-related phase changes across this band that is criticalfor speech as well as most acoustic instruments. Adding further complexity tothe circuit are the attenuators which allow the user to adjust the level of thetweeter or the midrange driver. The documentation doesn’t say how much thelevels can be adjusted by, but we will see what they do in the measurementssection. The L100 Classic does not provide bi-amping or bi-wiring capabilities,and that would probably be a sensible decision given the existing complexitywith the attenuators.

The JBL L100 Classic Crossover Network Uses Premium Parts and Large Gauge Twisted Speaker Wire

Theenclosure is a fairly sturdy construction with a 1” thick front baffle and ¾”thick side panels and brace. There is a ‘V’ shaped bracing at the midsection togive the enclosure rigidity where it is most needed. There is a thick layer ofdacron-type damping material lining the interior sides of the enclosure, whichshould help to absorb internal pressure waves. JBL tells me it is thicker thannormal polyfill/dacron and so has higher absorption. There are no feet attachedto the cabinet. If the user wanted to add feet, I would recommend adhesiverubber dome feet so as not to alter or mar the cabinet itself. The grille frameis very solid, so these grilles won’t break easily if unattached, although theymay contribute to some diffraction effects when placed on the speaker. While thefoam of the grille is quite thick, it is still acoustically transparent, so itwon’t interfere with the sound very much (we will take a closer look at thegrille effects when we measure it). The grille is held on by some heavy-dutypegs for a ball-socket, so they won’t break off easily unlike so many cheapgrille pegs. Low-bass is abetted by a front-mounted dual-flared port with a 3”diameter and a 5 ½” depth. A port with those kinds of dimensions should bepretty resistant to turbulence, but that is needed since the bass driver iscertainly capable of moving a lot of air.

Listening Sessions

In my 24’ by13’ (approximately) listening room, I set up the speakers with afew feet of stand-off distances between the back walland sidewall, and equal distance between speakers and listening position. Iangled the speakers to face ahead in parallel directions as prescribed by theL100 Classic user manual. The listening distance from the speakers was about 9feet. Amplification and processing were handled by a Pioneer Elite SC-55. Noroom correction equalization was used. No subwoofers were used.

Music Listening

A great toolfor evaluating a loudspeaker’s naturalness is a recording that has a clean andclear recording of a human vocal. For this purpose, I found a fun new albumcalled ‘Not Your Muse’ by a British singer named Celeste. ‘Not Your Muse’ isprimarily R&B but is heavily tinted by soul, pop, and, to a lesser extent,jazz. It is quite a bit more energetic than traditional R&B, and I think itwill have broad appeal well outside of R&B. Celeste’s singing isreminiscent of Aretha Franklin, although her voice is a bit lower-pitched. Hersinging style resemblance to Franklin is not surprising as she cites Franklinas one of her chief influences. She displays a remarkable range and controlover her voice; she has a nicely mellifluous timbre which sounds great whethershe is singing with a full-bodied force or whispering softly and everything inbetween. The production is first-rate and Celeste’s voice is accompanied byjazz bands as well as orchestral players and everything is beautifullyrecorded.

‘Not Your Muse’sounded well-balanced and full from the first track onward on the L100Classics. Perhaps I was subconsciously expecting a bass-heavy tonality from thesight of those 12” cones, but that wasn’t the sound that I received. Thesoundstage was large and reached well outside of the positions of the speakers.The imaging wasn’t the most precise that I have heard from the most laser-likeloudspeakers. However, it was still good, and Celeste’s voice had a strongposition centered between the speakers. Celeste’s voice was reproduced withterrific detail but without being too forward or harsh. Her voice on therecording was so well articulated by the speakers that the aural rendering wasnearly photographic; her performance was very easy to picture from this sound.Instrumental accompaniment also sounded nice with a lucid presentation and goodimaging. There are many good tracks on this album, and many of them are strongenough to serve as singles. They all sounded great on the L100 Classics anddeserve to be listened to on loudspeakers as good as these.

Moving thehuman voice to a much wider palette, I listened to a 2019 recording of some ofBach’s cantatas that were performed by the Thomanerchor Leipzig (English: St. Thomas Choir of Leipzig)called ‘J.S. Bach: Cantatas, BWVV 33, 17, & 99’ from the Accentus label andstreaming from Qobus in 96kHz/24-bit resolution. It is fitting to have thesecantatas performed by the St. Thomas Choir and recorded at the Luther Church in Leipzig since Bachhad originally written them to be performed by that group back when he wasdirector of music at that church almost three centuries ago. I couldn’t say howthis performance compares to those of Bach’s day, but I can say these are somelovely pieces of music and the St. Thomas Choir gavea gorgeous rendition of these cantatas. Thisrecording nicely balanced the acoustics of the church space with the directsound of the performers and makes for a great demonstration of classical choralmusic.

The JBL L100's were able to reproduce the full scale of the performance with aplomb...

The firstthing that struck me about this recording on the L100 Classics is the scale ofthe performance. It sounded big, although the venue isn’t huge nor are theperformers a massive group. I would attribute it to the recording technique aswell as the reverberation of the Luther Church. It was a delicate balance oflocation acoustics and performers, and the L100s were able to recreate theseconditions with aplomb. Choral sections covered the width of the speakersgiving the impression of front-row seating, and I am sure this was due to closeproximity of the microphones to the performers. I also received this sense fromthe orchestral section which was performed by the Saxon Baroque Orchestra.Individual singers held a well-defined position in the soundstage whenperforming in solos, duets, and trios. Indeed, this recording would make for agreat demonstration of how not to lose precise imaging in large reverberantspace. Tonality sounded very good, and the instruments and vocalists allsounded natural and realistic. ‘Cantatas, BWVV 33, 17, & 99’ soundedgorgeous from beginning to end on the L100 Classics. The original L100s mighthave a reputation for being a rock’n’roll speaker, but on this album, the L100Classics proved to be just as adept with a more complex and genteel music genre.

With theannouncement of the break-up of Daft Punk, I figured it would be a great momentto revisit a work of theirs that ended up being a classic soundtrack, which is,of course, their score for ‘Tron: Legacy.’ Even today, more than a decade afterthat film’s release, we still hear elements of that score echoing throughmodern film and television scores. It is a brilliant blend of electronic andorchestral music and greatly adds to the epic, futuristic tone of the movie.One nifty aspect of the music is that it pays homage to the 1982 movie ‘Tron’with fat, vintage-sounding synths, so it does have a slight retro-future flavorgoing on, much like the movie to which it is attached. This music sounds ‘big,’it is bass-heavy, and it demands to be played loud, so it is a perfect fit forthe JBL L100 Classics. How well would the L100s tackle this colossal sound?

Not that Idoubted that the L100 Classics could rock, but they killed it with ‘Tron:Legacy,’ and I mean that in a good way. They delivered just the monumentalsound that I hoped for in an album like this. The sound was balanced andfull-bodied. Daft Punk’s synths sounded great, but it occurred to me whilelistening to this album on the L100 Classics at a lively level that not enoughcredit has been given to the orchestral elements for its success. Theorchestral sections, performed by the London Symphony Orchestra, were criticalto the sound here, and without it, it would not have nearly as much of an epicfeel or emotional gravity. Both the electronic and acoustic instrumentsproduced tons of bass, and the L100s handled the low frequencies like a boss. Subwooferswere not missed at all. Indeed, the bass in ‘Tron: Legacy’ made the L100’s 12”woofers sing. The throbbing bass violins, electronic bass, and percussion couldall induce that tactile ‘chest rumbling’ sensation that can even eludesubwoofers since the L100’s bass drivers were punching at higher bassfrequencies than subs are tasked with. The mid-bass headroom seemed to bebeyond that of many tower speakers even though the L100s are classified as‘bookshelf’ speakers (albeit ridiculously so). Hearing the soundtrack soundingthis good made me want to watch the movie again. The L100’s dynamic rangescaled with the ‘Tron: Legacy’ soundtrack magnificently, and they proved thatthey could do loud without losing their composure. If you want a speaker that lookslike it can rock but actually can rock and do so with finesse, the L100Classics are a terrific choice.

Forsomething a bit crazy and rambunctious that let the L100’s stretch their legsin a very different way, I queued up the album ‘Heavy Black Heart’ by theartist Death’s Dynamic Shroud. I always like to throw in something far out thatserves as a counterbalance to the more conventional music; I have heard whatthe speakers sound like with natural, acoustic music, but what about somethingtotally unnatural? ‘Heavy Black Heart’ is certainly that. Death’s DynamicShroud hails from the vaporwave genre, but they go beyond just addingdistortion to sampled loops from 80’s advertisem*nt music. The album is largelymade from sampled pop music but fractured, contorted, and reassembled intosomething strange, new, and interesting. It is like a psychedelic, self-awarecollage of pop music that takes conventional music and puts it through ablender for a hypnotic and fascinating new sound. Aside from the bizarre andwild soundscape it presents, I thought that ‘Heavy Black Heart’ would make forgood demo music for the L100s because of the pervasive use of heavy bassthroughout the album which should really wake up those 12” bass drivers.

They JBL L100s delivered just the monumentalsound that I hoped for...

Loading up‘Heavy Black Heart,’ I had previously left the volume at a rather high leveland didn’t realize that this album started with a very loud crash which had mediving for the volume control. This taught me not to underestimate the L100Classics, and I was certain not to make that mistake again. ‘Heavy Black Heart’is pure multi-track editing experimentation, and, as such, the soundstagepresented is all over the place. It is a recording probably intended more forheadphones, but on a capable set of hi-fi loudspeakers, it sounded positivelymanic. Sounds could image from nearly anywhere in the front hemisphere of mylistening position, but it was more than barely-controlled chaos; there was amethod to this madness. It was like musique concrete collided with the vapidestmodern pop music, and the resulting wreckage sounded great on the L100classics. They were able to recreate the gonzo soundstages and thump of thebass-heavy passages with a visceral wallop. This music could often have manylayers of sound activity that on a lesser speaker might just blend togetherinto anarchy, but the L100s kept everything clear and unambiguous. This wasabstract music that you could still tap your toes to, and the L100s managed toconvey ‘Heavy Black Heart’s rhythm and thump without losing the sheer weirdnessof the sound. There probably aren’t a lot of people shopping for vintage-styledspeakers with such avante-garde music listening in mind, but when the speakersand music sound this good, there ought to be.

Movie Watching

One movie Ihad been interested in watching but just didn’t get around to was the Netflixrelease, ‘The Midnight Sky’ with George Clooney. It concerns the efforts of ascientist in the arctic circle who tries to warn a crew of astronauts not toreturn to Earth because of some global cataclysm that had rendered the planetmostly uninhabitable. It looked like science fiction of a more cerebral type,so probably talky but with some imaginative sound effects. I thought it wouldbe a good opportunity to evaluate speech intelligibility for the L100 Classicsas well as an opportunity to catch up on a movie that looked intriguing.

After having watched the film, there were a few moreaction and effects setpieces than I expected, and that did give the L100’s achance to shine with something a bit more bombastic. Alaxandre Desplat’sorchestral score was surprisingly tender considering the morose plot, but itcould supply some real energy during the movie’s crisis moments, and the L100’swere more than up to the challenge of recreating the physical dread of thosesequences. Dialogue intelligibility was never a problem. The L100’s bassability was made abundantly clear in scenes in arctic storms where the gustingwind made a continuous rumble, and the verve at which the L100’s reproducedthose low-frequencies were very much on par with what a good subwoofer coulddo. While ‘The Midnight Sky’ has some scenes of questionable scientificaccuracy, the emotional core of the story was strong enough to help me forgivethose sins, and the terrific soundmix as heard on the L100 Classics also helpedto make the movie that much more enjoyable.

Another film that I finally sat down to watch was ‘HarleyQuinn: Birds of Prey.’ It looked like it would have a rowdy sound mix thatwould go great with the L100 Classics. The music score was a mixture of rock,punk, and hip-hop, and the sound mix promised lots of limbs snapping, baseballbat violence, and swearing. This is a colorful movie, and these are colorfulspeakers, so it should make for a great combination. Indeed, they did make agreat pairing. ‘Birds of Prey’ had high-energy music from start to finish, andit was a blast to hear on the L100 Classics. One thing that surprised me washow well choreographed the action scenes were. The effect sounds as reproducedby the L100s were as brutal as the imagery. Thumps and thuds from kicking,punching, bat strikes, and hammer blows, gunshots, crashes, shattering glass,and explosions all had a weight and impact beyond that of normal home audioloudspeakers. Speech intelligibility was very good throughout, althoughsometimes the music drowned out the dialogue, but that was a problem stemmingfrom the sound mix, not the audio system. For the most part, the sound mix waswell-balanced and sounded terrific. It was a movie that demanded to be playedloud, and the L100s satisfied those demands effortlessly. Even though I watched‘Birds of Prey’ on a two-channel speaker system with no subwoofers, I didn’tfeel as if I had missed anything. I don’t think a surround sound system wouldhave provided much improvement beyond the sound that just a pair of L100Classics could provide. They had a full, enveloping, vibrant sound, and madefor a quite enjoyable time at the movies.

JBL L100 Classic Bookshelf Loudspeaker Measurements & Conclusion

The JBL L100Classics were measured in free-air at a height of 7.5 feet at a 2-meterdistance from the microphone, and the measurements were gated at a9-millisecond delay. In this time window, some resolution is lost below 250 Hzand accuracy is completely lost below 110 Hz. Measurements have been smoothedat a 1/12 octave resolution.

The abovegraph shows the direct-axis frequency response and other curves that describethe speakers’ amplitude response in a number of ways. For more informationabout the meaning of these curves, please refer to our article Understanding Loudspeaker Measurements Part 1. At a glance, the response is not as neutral as we havecome to expect from other modern JBL products like the HDI-3800which had a terrifically flat response. The major linear deviations occur witha dip at around 1kHz, and two resonances at around 2kHz and 5kHz. The peak ataround 5kHz would stand a chance of being glaring - if these speakers werelistened at an on-axis angle. However, that is not the way they are intended tobe used, so the above graph is potentially misleading. We will discuss this abit more below.

The abovegraphs depict the L100 Classic’s lateral responses out to 90 degrees infive-degree increments. More information about how to interpret these graphscan be read in this article: Understanding Loudspeaker Review Measurements Part II. In these graphs, we get a better look at what exactly isoccurring at off-axis angles. One thing to note is that some of the resonancesdon’t quite hold across the front hemisphere of the speaker. There is nothingwildly uneven, however, there is a bit of waviness here and there, and it isangle-dependent. What that means is that this wouldn’t be an easy speaker toequalize with precision. Since the overall response holds to a relatively evenbaseline, you could do broad equalization with tone controls to control itssound. The front-mounted tone controls are somewhat capable of doing this, andwe will show their results below.

The abovepolar map graphs show the same information that the preceding graphs do butdepict it in a way that can offer new insight regarding these speakers’behavior. Instead of using individual raised lines to illustrate amplitude,these polar maps use color to portray amplitude and this allows the use of apurely angle/frequency axis perspective. The advantage of these graphs is theycan let us see broader trends of the speaker’s behavior more easily. For moreinformation about the meaning of these graphs, we again refer the reader to Understanding Loudspeaker Review Measurements Part II. In this graph, one interesting aspect that leaps out isthe asymmetry of the off-axis dispersion. We would expect this, naturally,given that the speaker itself is vertically asymmetrical, but it’s stillinteresting to see how that manifests itself. Much of the asymmetry happensfrom 600Hz to about 5kHz. Up to 16kHz, this dispersion pattern is actuallyquite broad. The waveguide on the tweeter is really doing its job in keepingthe tweeter from beaming in high frequencies. That only works up to a point,naturally, but that point is so high up in frequency that it scarcely mattersanymore.

The above graphcompares the on-axis response to the response at 30-degrees which is typicallywhere a listener would sit between the speakers when they are facing forward ina parallel direction. The user manual states that the speakers should be facingstraight ahead instead of toed-in toward the listener, and in that case thedirect response to the listening position is significantly more neutral thanthe on-axis response. This is how I listened to the speakers. I had listened tothe speakers for quite a while before I had measured them, and I was surprisedto see that resonance at 5kHz since I didn’t hear anything like that in my ownlistening. I am normally pretty sensitive to elevations in response in thatarea which makes the sound more sibilant. We do see a more peak at 2kHz at30-degrees, but that may not be much of an offender since stereo crosstalk canoften reduce the region around 2kHz from a comb-filtering effect (here is a paper that describes this phenomenon). While early-reflections will also play a big role inthe spectral composition of perceived sound, the direct sound is stillparamount, so I would encourage users to follow the user manual guidelines onspeaker placement for the L100 Classics.

The abovegraph shows the L100 Classic speaker’s response behavior along its verticalaxis where zero degrees is directly in front of the tweeter, negative degreevalues are below the tweeter, and positive degree values are above thetweeter. It should be said here that thevertical response isn’t nearly as critical as the horizontal response, so animperfect vertical dispersion is much less of a problem. This graph tells usthat the most neutral response occurs on-axis, with the tweeter facing thelistener. However, if you give or take ten degrees up or down from the tweeter,the sound should stay pretty steady. Outside of a +/-10 degree vertical angle,you do start to run into crossover cancellation nulls. What is surprising ishow mild these dips are, in fact, many of the vertical angle responses aresurprisingly stable for a three-way speaker of this type, especially one using2nd-order crossover slopes. One possible explanation for this is that all ofthe drivers are mounted relatively close to each other on a vertical plane,since the drivers’ distance from each other is what exacerbates these nulls.The advantage of such good uniformity of vertical dispersion is thatreflections will not differ much from the direct sound, so this is a speakerthat will have more benign acoustic reflections from the floor and ceiling.

The abovegraphs show the L100 Classic speaker’s low-frequency responses that I capturedusing groundplane measurements (where the speaker and microphone are on theground in a wide-open area). This is a very flat and well-controlled bassresponse. I would guess from this graph that the port tuning happens somewherearound 40Hz where the low-end slope becomes steeper. The roll-off looks tostart at 80Hz but is quite gradual until 30Hz, so this speaker looks to beasking for just a little bit of help from low-frequency room gain which it willsurely get. A flat response down to port-tuning would have potentially yieldeda bloated bass-response in-room. Most users in a typical room should be able tocount on solid bass down to at least 40Hz and likely a bit lower.

The abovegraphs show the electrical behavior of the L100 Classic speakers. As JBLstates, these are 4-ohm speakers and consistently so out to 20kHz. I wouldn’tadvise these to be driven by a budget amp, but then few people who do get apair will contemplate doing that. We can see from the low-end saddle that theport-tuning frequency is around 35Hz. The much taller height of the first peakin the saddle shape indicates that the bass driver’s resonant frequency is muchlower than that of the enclosure. Overall, this is not an especially tough loadfor a good amplifier, with the minima being just a hair under 4-ohms at justover 100Hz but with a somewhat steep phase angle. Whatever amp the user pairsthis speaker with needs to be comfortable with 4-ohm loads, at least for loudlistening. I measured sensitivity to be 90.2dB for 2.83v at 1 meter. That isvery close to JBL’s spec of 90dB. That is relatively high sensitivity so theycan get loud without a huge amount of amplification.

The abovegraph illustrates the difference that the grille makes in the on-axis response.It is not a completely transparent grille, but it doesn’t change the responsethat much. The difference is due more to the frame than the Quadrex foam cover.I included this for those who are curious about the effects of such an unusualgrille. Common grille effects are discussed in this Audioholics article: Speaker Grilles On or Off: Which Way Sounds Better?

The abovegraphs exhibit the effect that the front-mounted tone control knobs make.Curiously, there is a lot more room to lower the response than raising it forboth the mid and high-frequency knobs. The overall flattest response seems tooccur with the knobs set to zero as would be expected.

Conclusion

The JBL L100 Classics prove that fun and high-fidelity canexist at the same time. Many other “fun” speakers crank the bass and treble foran exciting sound, but that kind of sound grows wearying fast, and it is nogood for content that strives for realism. The JBL’s sense of fun comes fromthe dynamic range enabled by the design of the unit as well as its splashyretro look. Good sound doesn’t have to come from audio components that look soserious that they would be at home in the inner sanctum of a cathedral. TheL100 Classics look like they are good rock’n’roll speakers, but the truth isthey are just good speakers for whatever you throw at them.

Let’s nowbriefly go over the pluses and minuses of the L100 Classics, and, as always, wewill start with the minuses. One potential minus of owning them is the somewhatawkward form factor; they are too short for floor-standing speakers but awfullybig for stand-mount speakers. As was discussed before, JBL has stands for themthat are pretty sensible considering their size and shape, but outside ofthose, you are going to want a heavy-duty but short speaker stand for them;they need fairly particular stand criteria to work well.

If you want a speaker that looks like it can rock but actually can rock and do so with finesse, the L100 Classics are a terrific choice.

Anotherminus is that the response isn’t as neutral as other speakers from JBL that canbe had. If you are interested in sheer accuracy, the HDI series or 7 SeriesReference monitors are a better choice. This is not to say that the L100Classics are badly inaccurate, but the response is a bit ragged compared toJBL’s designs that aren’t bound to a 50-year old form factor. The L100 Classicsare a far more capable and higher-performing speaker than the originals, butsome of the design cues that the L100 Classics are obliged to follow from theoriginal L100s do constrain what JBL can do for a performance profile.

Onepotential minus is an obvious one: the aesthetics are a love-it-or-hate-itdeal. Few people are going to see the L100 Classics and be on-the-fence abouttheir appearance. I quite like them but they aren’t going to be an easy fitinto homes that are going for an austere interior decor.

With the minuses out of the way, let’s go over theirhighlights, the first of which is their sound. The L100 Classics may notmeasure perfectly, but they sound terrific nonetheless. A look at the basicon-axis response wouldn’t do justice to them, and a deeper look at theiroverall acoustic behavior gives a better indication of their sound. When usedas recommended, they give a full, natural sound that is balanced and open. Theyhave a wide dispersion that makes for a broad soundstage and spacious sound aswell providing coverage over a wide area over their front hemisphere. Theirdynamic range is on another level from most home audio loudspeakers, so if youwant something that can get loud without compression or distortion -especiallyin the bass range where loudspeakers most commonly begin to exhibit dynamicrange limitations- the L100 Classics are a great choice. They don’t need atremendous amount of amplification to get loud either.

The L100 Classic’s low-frequency extension is very good,and if you enjoy bass-heavy music at loud levels, they will do nicely. The realstar of the show here is that 12” woofer; there is not much it can’t do. Withport-tuning at around 35Hz, there isn’t much music bass that it is going tomiss, even for bass-heavy electronic genres. It is such a capable driver that anormal subwoofer would be more likely to degrade the bass than add, even if ithad lower-frequency extension. The reason is that it would take a serious subto match the dynamic range of the L100 Classic, and an average subwoofer wouldchoke at the kind of mid-bass dynamics these speakers can do in that samefrequency range. I would be looking at some of the better subs starting aroundthe $1000 range that could actually make a positive contribution to a speakerlike the L100 Classic if you wanted to extend the low-frequency response of thesystem. I should add that with all the praise of their bass ability, the soundwasn’t bass heavy but rather it could reproduce bass with remarkable authority.

The buildquality is very good. The drivers are serious when you examine the motors andoverall construction, and the capacitors and inductors in the crossover circuitare real chonkers. The cabinet might have used a couple more braces, but I’mnot sure how much good that would have done, and the speaker was already veryheavy at nearly 60 lbs (that’s around 27 kg for all you metric-system kids forwhom easy division by ten is all the rage).

The JBL L100Classic is an eccentric speaker but one that is very easy to enjoy. Olderaudiophiles who grew up with the original L100 Century speakers are sure toenjoy this new iteration, and younger audiophiles with a taste for vintagestyling are going to enjoy the powerful sound. As was said before, it is not aspeaker for everyone, but if you have read this far into this review, yousurely know where you fall on that divide. I, for one, had a great time withthem, and everyone that I showed them too were quite enamored with the uniquestyling as well as the impressive sound. Since times have changed and so havetastes, I don’t think JBL will see the kind of sales with these that theoriginal L100 had. However, I do think that if more people get exposed to the sightand sound of the L100 Classics, JBL will certainly have another hit on theirhands.

The Score Card

The scoring below is based on each piece ofequipment doing the duty it is designed for. Thenumbers are weighed heavily with respect to theindividual cost of each unit, thus giving a ratingroughly equal to:

Performance × Price Factor/Value = Rating

Audioholics.com note:The ratings indicated below are based on subjective listening and objective testingof the product in question. The rating scale is based on performance/value ratio.If you notice better performing products in future reviews that have lower numbersin certain areas, be aware that the value factor is most likely the culprit.Other Audioholics reviewers may rate products solely based on performance,and each reviewer has his/her own system for ratings.

Audioholics Rating Scale

— Excellent
— Very Good
— Good
— Fair
— Poor

Metric	Rating
Build Quality
Appearance
Treble Extension
Midrange Accuracy
Bass Extension
Bass Accuracy
Imaging
Dynamic Range
Fit and Finish
Performance
Value

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