Sunday, 29 November 2020

MEASUREMENTS: Fluance Reference XL8S Bookshelf speaker. (Blog post #401 with a brief look back...)

 

Let's continue with discussions and measurements of bookshelf/desktop speakers. As I expressed a few weeks back, these days I've transitioned to using passive speakers on the computer workstation table with the S.M.S.L. SA300 Class D amplifier. It has enough power I believe for almost any speaker one might want to use nearfield with great energy-efficiency.

What I have on the tabletop today is a pair of new Fluance Reference XL8S speakers that was released recently in summer 2020. These are the walnut veneer version (known as XL8SW). Fluance is a Canadian brand and over the years, may be more well-known for their affordable turntables (eg. the Fluance RT81 Elite looks nice with the RT85 Reference for their higher end), but their product line also includes speakers - other passive bookshelf models include the SX6 out since around 2014, and more recently the Signature HFS (released 2016). I see that they also have floor-standing versions.

What I find interesting is that among the bookshelf product line, all these speakers are priced very similarly! All three of the bookshelf models - the SX6, Signature, and Reference are within US$50 from each other from US$150-200 with the Reference model I have here sitting in the middle currently priced at US$180. All three are 2-way designs although the drivers look different and there are differences like whether front or rear ported.

I. Physical characteristics

Here's the box on arrival for the Reference XL8S:

Not the robust triple-boxing as described for the Edifier S2000 Mk III. :-) The box looks a bit roughed up in transport, but it's good enough to keep the speakers safe inside. As you can see in the first picture, it comes with a color brochure, a basic manual, and some rubber stick-on "footers".

Here's a look at the front and rear:


We're looking at a shiny flat front baffle with strategically placed metallic areas for the magnetically attached grille. It's nice to not have holes or attachment posts sticking out although there are two front ports so I would still prefer keeping the grilles on for esthetic reasons. It's a convenient size, measuring 11.4" x 8.1" x 9", 11.35lbs each and the front ports help ease placement.

Due to the side curvature and taper, the rear looks more slender. The 5-way binding posts are of good quality and accept banana plugs snugly.  There's mounting hardware for on-wall placement, and I like the thoughtful little bumpers already in place at the bottom rear if you do place it against a wall. They have a little Canada flag by the binding posts; this product is designed in Canada but as you can imagine for speakers in this price range, are "Made in China".

Drivers are silk 1" tweeter and 5.25" "woven glass fiber" mid/woofer with butyl rubber surrounds - should be good for many years of service. As an online purchase, they have a 30-day return policy and I saw "lifetime warranty" on their passive speakers.

Here's a better look at the magnetically attached grille with the fabric mesh:


As you can appreciate from the pictures and dimensions, looking at them from the front, they're more "squat" looking than slender. The walnut vinyl veneer looks good although construction is not perfect; I see a few small irregularities at the seams along the edges but nothing distracting unless one were really picky and obsessive! Given the price, the construction is very good.

II. Let's Measure! Impedance and qSpin...

Okay, so we have these in the basement now on the stands as previously discussed / described. You can see the Emotiva XPA-1L amplifier under the table driving them for the measurements. 

First, let's have a look at the speaker impedance and phase curves:

As you can see, the box resonance frequency is 54Hz. Impedance dips down to 6Ω at 2-3kHz. This should not be a challenging load for most amplifiers these days. Fluance rates these speakers as "8Ω compatible" in their specs which is appropriate. There are a few little "kinks" suggesting possible resonances around 280, 550, and 1.5kHz.

The speaker EPDR does dip down to a minimal level of 3.5Ω around 150Hz which is low but remember that many speakers these days (like the KEF LS50) have portions that dip down into the 2Ω range.

With 2.83V output, here's the sensitivity graph calculated from 500Hz to 7kHz.


Not bad, it's rated at 85dB/2.83V/m and I'm basically on average getting that.

What we see in the plot above is a frequency response with a gradual downward slope from about 1.5kHz. This could be pleasant sounding. Let's see the "qSpin" consisting of both 1m gated results blended with summed nearfield frequency data including port output:


The qSpin result for the "Listening Window" shows a non-flat response with 3 regions of accentuation - 90Hz bass, around 1.2kHz midrange, and some "sparkle" up at 10kHz. Between 1.5-8kHz particularly, it's unfortunately rough.

That accentuation around 90Hz perhaps subjectively increases the perception of bass presence. The company spec claims frequency response down to 50Hz without further qualifications. Interestingly, I found this still image from a YouTube video about "What is Speaker Sensitivity":


Notice that the frequency response for the "XL8S" label is listed as "60Hz-20000Hz"; I wonder if this was an early pre-production label? I think 60Hz on the low end would be a more realistic -6dB figure based on what I'm finding.

The directivity indices bounce around a bit and particularly into 6kHz, it widens out resulting in a low value DI. From there, the dispersion narrows into 20kHz as the directivity index goes above 10 (tweeter beaming). We can see this with the horizontal and vertical polar maps:


The crossover is spec'ed quite high at 3.1kHz which correlates with the dips close to 0° on the vertical polar map.

Horizontally, the dispersion width suggests staying within +/-30° for best listening. Vertically, one should sit at or slightly below tweeter axis; best to stay from 0° to -25°. On my desktop, I used AudioEngine's DS1 risers (which I previously paired with the AudioEngine A2). Although they look a little small for these speakers, the arrangement was actually quite stable. This tilts the angle up a bit towards ear height which notably improved the sound:


On my deep brown tabletop, the XL8S vinyl wood veneer blends quite nicely. As you can see, the size also fits my desktop quite well and won't intrude too much into my wife's work area behind those speakers. ;-)

One thing you'll notice on the Fluance website is their "official" frequency response graph. Remember that aspect ratio has a significant effect when we're examining frequency response graphs! Not only that, the Fluance graph has a 60dB range on the Y-axis while mine is only 30dB for the qSpin graph above. Let's use those settings and rescale/relevel, then overlay my "Early Reflections" curve (which would be closer to an in-room response) onto the official Fluance curve for comparison:

Clearly there are a number of differences. I don't see a description of how Fluence measured, whether in a true anechoic chamber or pseudoanechoic, whether this is on-axis or spatially averaged, or what kind of smoothing was applied. We're also not clear whether this was with a production box or with/without the front grille in place. For the record, the box I measured had serial number 2005023XX.

III. Some Time Domain Stuff...

Alright, let's now look into the time domain. Here's the step response, across the first 3ms:

A common passive crossover arrangement with both tweeter and mid/woofer arranged in positive polarity. The little "step" between the tweeter and woofer around 300µs suggests that the acoustic center should be a little lower than tweeter height and is consistent with what the vertical polar map is telling us.


The cumulative spectral decay waterfall over 3ms (~25dB range) shows us that the box is overall more resonant than the KEF LS50 or Edifier S2000 Mk III (previously measured). The waterfall decline is also a bit rough especially in the treble frequencies. It takes a bit more time for the energy up to 4kHz to settle especially. There's noticeable resonance around 3-4kHz, and also a rather "cute" bit of extra energy at 9.4kHz where the cursor is placed (I doubt this is audible).

IV. Dynamic Linearity and Distortion

Okay, let's see how well it tracks a 200ms "transient" burst from 70 to 100dB SPL amplitude, relative to 0 at 85dB SPL (the Emotiva XPA-1L amplifier was used):

Not bad. We see less than +/-1dB across the 30 dB range.

Here's the THD graph across the audible spectrum with playback at ~85dB SPL:

-40dB correlates with 1% THD so it looks like distortion stays relatively low through most of the frequency range. Remember, below 60Hz, the bass drops off quickly so most of what's detected is just background noise or distortion. Notice that most of the distortion is 3rd harmonic at this ~85dB SPL playback amplitude.


At 60/70/80/90dB SPL @ 1m, intermodulation distortion remains essentially at or below 1%. We can compare this to a much more expensive speaker like the KEF LS50 and see that at 90dB SPL, the LS50 remains clean with -56dB distortion whereas the inexpensive Fluance seems happiest playing around 80dB SPL and intermodulation distortion increases significantly by 90dB with a prominent 700Hz distortion among others.

V. Stereo Pair comparisons

These speakers come in a stereo box. Let's see how well matched they are with the impedance response, frequency response and cumulative spectral decay.

Stereo pair impedance.


I rarely see stereo pair comparisons examined and I think this is one area that's important to review (regardless of price!). Significant differences may be reflective of less precise component matching whether it be the parts used for the crossover or speaker parts like the voice coils.

For the Fluance speaker pair, the frequency response matching is less precise compared to the pair of KEF LS50 or Edifier S2000 Mk III (both of which more expensive). Otherwise, the impedance matches nicely and the CSD is relatively equivalent down to that little ~9.4kHz resonance. The "right" speaker seems to be a little more resonant below 2kHz than the "left" one (of course, which speaker I declare "right" or "left" is arbitrary).

Comparing the two speakers, notice that there's some frequency deviation around 3.5kHz (possibly related to 3.1kHz specified crossover point?) - thankfully the mismatch appears to be affecting a narrow frequency range.

VI. Subjective Listening & Summary

From the measurements, we can obviously say that these Fluance XL8S bookshelves are not flat-response speakers. Indeed, subjectively these sound very different than the KEF LS50 or the Edifier S2000 Mk III playing on my computer workstation desktop as I listened to them before performing the measurements. These are not as "smooth" sounding as the Edifier nor as analytical as the KEF LS50. Rather, they seem to be aiming at being "pleasant" for longer term listening. The diminished upper-mid and "presence" frequencies accentuates the bass and sweetens the "brilliance".

For example, on a track like Dave's True Story's "Like A Rock" (Dave's True Story, 1994), the bass was rendered with a good sense of low-end authority and sibilance in the female vocals well controlled. While these are not the highest-resolution speakers I've heard (finger snaps not as clean), it's still good, able to reproduce each bass pluck with nice definition and Kelly Flint's voice sounds natural even if slightly recessed.

While it's not able to reproduce the really low bass/sub-bass (as usual for bookshelves), when listening to He Xun-Tian's Mystical Scent (神香) (2007, DR12), one gets a taste of deep bass presence even if one cannot fully appreciate the magnitude of the sub-bass; check out Sa Dingding's song "Mystical Scent" or the sonic depths of track 5 "Tibetan Drama Dance" to hear what I'm referring to.

One area that I thought these speakers were a bit weaker at was soundstage rendering. By no means is it poor - just that compared to other small speakers the instrument and vocal placements didn't seem as precise. I can't know for sure if it's the case, but I wondered if this is related to how precisely the speakers matched on the frequency response. For example, I mentioned previously with the LS50 discussion that "One Day More" off the London Cast of  Les Misérables (1985) provided a nice test of the stability for each vocal part in the soundstage. The Fluance in comparison to the LS50 just didn't "anchor" the singers as stably especially for the more subtle positional differences of voices placed closely beside each other.

Comparison of the more "squat" Fluance XL8S vs. my more "tall and lean" >20 year old Tannoy mX2. In many ways I think they sound comparable although I think the Fluance has more bass even though the Tannoy has 6" mid/woofer, is rear ported but sounding smoother in the treble. I have not measured the Tannoy yet, but likely will in the days ahead to evaluate a more "retro" speaker. ;-)

One last measurement. You might be wondering, "Is it better to have the grilles on or off for this speaker?" Let's have a quick look on-axis:

Unlike the Edifier S2000 Mk III where we saw with the "MONITOR" DSP setting that it achieved a smoother frequency response with the grille on, here's an example with the Fluance where we see the opposite; grille off is smoother. I think this is a good example of how objective testing can give you an answer quite easily but of course, one should double check in the listening room.

Okay, bottom line guys and gals. The Fluance XL8S is an inexpensive speaker. As a budget product at the price of around US$180, there is certainly good value to be had here. It's built well, the convenient size and front ports provide placement flexibility, and the curved sides and walnut vinyl veneer model that I have here add a bit of style to the physical presentation (very much dependent on your décor of course).

Do not expect a "neutral" sound however, but one that accentuates the bass a bit and adds "brilliance", sparkle and "air". Remember to listen slightly below tweeter level, so make sure your speaker stands are tall enough or maybe angle the speakers up a bit like on my desktop. Another option might be to listen to them upside down with tweeter below woofer (like the PSB Alpha P5)! Alas, I wish they didn't have that "FLUANCE" name so obvious on the front panel. :-(

Despite the imperfections, I suspect many listeners will subjectively like the sound. Since this is a new product, there are only a few reviews on places like Amazon at this point. As for myself, I could easily see them being used in my secondary sound system or as surround speakers. They would make a great entry-level pair for a young family member. Hey, back in the '80s, I started listening with lightweight and hollow-sounding mass market speakers of much worse quality, and it was still tons of fun! For my computer workstation, unless EQ'ed, these speakers would not be neutral enough for my needs.

For completeness, I think it's good to compare with the XL8S's close relative the Fluance Signature HFS. That model's list price is just US$20 more (but can be found on sale). Physically it also has dual front ports, but taller and the mid/woofer looks to be different with its pointed phase cap, and lower crossover frequency listed at 2.3kHz. Audio Science Review has measurements. Comparatively, the HFS look like they're "brighter" speakers overall. They both have irregularities through 1-5kHz, and the vertical polar map suggests they both sound best below tweeter axis.

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Wow. Just noticed that with today's post, we're up to 401 articles on the blog since inception. Of course, that's not a huge number compared to many other sites but I think the articles here tend to be pretty long and "denser" than most blogs.

I actually could not have imagined that in 2020, I would still be writing stuff on the topic of audiophilia! Back in 2013 when I started writing, I was just trying to put up a few articles looking at the high bitrate MP3 blind test and the results.

Over the years, I think we've covered a lot of material here and while there's more to say and do, as a "more objective" audiophile, there's also a limit to how much I actually care once some answers have been found to satisfy my curiosity. This is perhaps one area of difference between an "objectivist" from the pure "subjectivist". Unlike magazines that seem to tout "best sounding amplifier ever" in perpetuity, the objective audiophile I think recognizes that at some point, this is simply not possible and in fact rather silly; there is such a thing as "more than good enough"... I know, the "high end" audiophile industry will be unhappy with this assessment! After all, how can one imagine that they might not be able to keep using the "best sound" argument as a selling point for the next generation of products?!

Around 2013, with the advent of the transition to asynchronous USB DACs, we have been able to follow the improvements in jitter performance. With the advent of inexpensive SBCs like the Odroid and Raspberry Pi, we have followed the evolution of high quality streaming and recognized that the digital source really doesn't affect sound quality significantly with good DACs. We have followed the hype of Pono and discussed the questionable need for "hi-res audio". We have looked at the (IMO) scams of audiophilia like MQA, talked about the decades of snake oil, examined Synergistic stuff, and silly software like JPlay. Along the way, we've explored the more pedestrian topics like whether lossless formats sound the same, evaluated cables (both analogue and digital variants, argued with silliness), the minimal differences USB hubs made, discussed ethernet switches, explained about "bits are bits", and countless musings related to the audiophile press and their typical irrationality plus expressed the philosophy of achieving high fidelity and how we can approach it as hardware enthusiasts. We've looked at the microscopic impulse responses, understood what digital errors sound like and I think stopped worrying about jitter. We've discussed DSP room correction, evaluated server-side software (like Roon and computer-related stuff), and even done a few other blind tests along the way! Hey, we've even "infiltrated" audio shows here and there with commentary as a "more objectivist", visited dealerships locally, in North America, and abroad.

After 8 years of running this blog, personally, I'm glad to have collected a heck of a lot more knowledge and experience, and worried a lot less about the minutiae that actually make no difference by exploring the principles rather than holding on to beliefs and following suggestions because someone (Golden Ear? Audiophile High Priest?) said so. I hope you've benefitted from these thoughts and measurement results as well. For the most neurotic among us (myself included), I hope you're much less anxious about the "high-fidelity" hobby and finding yourself well along the way to being liberated from many of the unsubstantiated beliefs so readily promoted as "truths" over the decades.

Stay safe as we enter December, friends.

I hope you're enjoying the music, and the sounds of the season!

Addendum December 20, 2020:

Here's a FIR correction filter for those who want to try getting a flatter frequency response...

Fluance XL8S FIR Correction (Stereo 24/96).zip

Let's deal with that mid-range bump and strengthen the upper-mid and "presence" frequencies.


13 comments:

  1. It was probably 2015 when I discovered this blog and then within a few weeks read all your previous posts. Since than, I never missed a post.
    Being poisoned by whathifi, Stereophile, TAS and many others, I felt that I finally found an oasis of technical knowledge, common sense and humility which were impossible to be found literally anywhere else.
    This is THE place where I cured my 'audiophilia neurosis', being previously convinced that everything matters, that cables have decisive influence on sound, that jitter has horrendous effects, that streamers sound drastically different and that good fidelity depends on countless factors and therefore is nigh impossible to reach.
    Your honest and open approach to all things audio, including our perceptipns, as well as putting things in real perspective regarding magnitude of influence, gave me a piece of mind and real knowledge.
    Now it seems you are steering your attention towards the most influential component beside the room - the speakers.
    Thank you for all these years of education, fruitfull discussions, myths busting and honesty.
    I hope you will keep your motivation going forward and give us many more inspiring posts. Keep this excellent work, be joyful and enjoy music :-)

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    Replies
    1. I couldn't have said it better myself.

      Thank you, Archimago, for maintaining this lighthouse, a rare beacon in those grim audio seas.
      Kudos as well to all the regular constructive contributors in the comment section.

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    2. +1 from here. I think I started reading your blog in January of this year. I found it when searching for computer audio streamers. There's a lot of misinformation out there on that topic that you helped me see through. Your writing on audible differences, HD audio, LP fidelity, and other topics helped me settle on a digital playback system that works great for me.

      I've also dabbled in building my own components over the years with mixed success. Your articles on raspi streamers, HATs, and Hypex amps inspired me to explore this area again and it's been a blast.

      Cheers to you on crossing the 400 milestone. Looking forward to reading more of your musings.

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    3. As usual a exemplary review. You data point and analysis is superior to anything I have seen in my 45 years of audio exploration. A local dealer here in Cornwall Ontario BenDav a father/son operation has long been closed. Dad passed a few years back and the son was over for an audition of my 5.1 Klipschorn system. I had a lame channel and he gave me a Nuance speaker I will look it up. It is almost non audible in my Onkyo 5.1 120watt a channel system. between a pair of 1981 all original K-horns that is not usual unless you have a another horn loaded speaker. I purchased a Cornwall used from someone and Covid has kept me from picking it up. so the Nuance will be given to one of the local bars I hang for HH.LOL It is clean soft spoken and adds a center presence that is in the background. The cornwall will bring it to live. Just think a Cornwall in a 5.1 all Klipsch system in Cornwall Ontario. I should get a shout out from Klipsch. I will blog and You tube ya . Cheers and keep the reviews coming. Your site and Mark Walrep are the most knowledgeable Audio guys in the marketplace. You have enlighten many and I learn something with every read. Thanks

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    4. Thanks everyone for the comments.

      It has been a fun journey so far checking out the stuff and getting hands dirty to try to understand and obtain some answers around what I would think are significant questions audiophiles should have... Yet (perhaps not so oddly) the typical mainstream audiophile magazines never seem to have or desire to speak of.

      There's of course no need for mystique or opacity in much of the typical audiophile claims!

      Hey Glen, sounds good passing those speakers along to the local watering hole.

      I have not checked but I hope the Fluance company has nothing to do with the old Nuance company with those speakers you have. For us Canadians, many might remember the Nuance brand from the 1990's (maybe early 2000's?). I was living in Calgary at the time and went to one of the demos they had... For sure they were using QSound to make it seem like the speakers were projecting more "3D" surround effect than with normal tracks (I remember one of the tracks being from Roger Waters' Amused To Death) with a bit of a hard sell on their large tower speakers. As a co-op student at the time making only a few bucks with a loan to finance, it was expensive (few thousand bucks as I recall) so "thanks but no thanks"!

      Delete
  2. Hey Arch, sent you an email. Not sure if you just haven't been on email or it got blocked in a spam filter. I've had the latter happen to me once or twice in the past with other folks. Thx.

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    Replies
    1. Thanks Allan,
      I'll have a look at the Outlook account soon. I've been bogged a bit by work over the last month arranging a multiweek virtual conference with folks overseas (making sure communications smooth is a real pain!). Chat soon ;-).

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  3. Goran wrote - "Now it seems you are steering your attention towards the most influential component beside the room - the speakers." this is also my experience - that speakers matter the most.

    I know that the wilson company - at a show - did a demo with an ipod and i forget which wilson speakers were used - but they were advocates that the speaker made the most difference. and many people that were there - agreed

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    1. Hi Stewart,
      Yes, absolutely agree and hope more companies will take that stand as well. No problem with an iPod demo; hey even the old iPod Classic measured and sounded well :-)
      http://archimago.blogspot.com/2016/09/retro-measure-2006-apple-ipod-classic.html

      No jitter and good 16bit low noise floor even for a 2006 device; presumably the newer solid state iPod models even lower noise level.

      The idea that it's really the speakers, room, and maybe amplifier making the most difference I trust should be "hi-fi" wisdom after all these generations. Of course companies that sell five-figure digital streamers, DACs, and cables would like us to think otherwise for obvious financial reasons.

      While many of the tests and results yielded not unexpected outcomes (eg. cables, jitter, digital devices), as a "somewhat" obsessive guy myself, these are some of the basics and foundation upon which we must know in order to not be bogged down in the minutiae. The Industry wants us to believe that "hi-res audio" sounds so much better, or that their magical wires are indeed magical. These are schemes, scams, frauds, and imposters.

      I hope the published, measured results will allow some audiophiles to be cured of their "audiophilia nervosa" affliction. And at the very least, if companies still insist that their products can improve on things like jitter or noise, then present a challenge for them to just show it. I'm happy to be wrong if indeed a company has the technical ability to improve fidelity!

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    2. Just to echo the other commenters, I am very grateful for your posts and read them all. I am, however, completely ignorant about the details presented here, but I know good sound when I hear it and my L910's and a NAD 208 thx balanced amp are my end-game stuff. Just posted your last post, the "BS" one, to Audio Bullshit on FB. Perfect and I'm sure most will appreciate the dig on Theddy.

      Oh, and I have a pair of L810's on this desktop. Best-sounding near-field speakers I own. Not going to stay here, though 'cause I want a 32" curved monitor for gaming and right now, things are too crowded for that. I also have these Fluance bookshelves, but I have a lot of bookshelves I think sound better, so I'm still looking for someone to give them to. ( They sound fine; I just have better)

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  4. Goran said it all, and certainly way better than I could, so I just want to echo his comments. Your Blog is without any doubt my preferred audio reading. Thank you so much, keep up this excellent work and "meilleures salutations du Québec"

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  5. I think you raised a good point about stereo, or measuring both speakers to Sée if they match.

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  6. 80's music rocks (and pops)!!!!!!

    - Erin

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