JBL L82 Classic: Spinorama and Measurements

[napilopez]

It's been a while! I've had the JBL L82 for some time now, and as far as I know, there are no published measurements for it yet. So here I am =]

An incomplete post for now. Full suite of measurements and interpretations once I've published my review and formatted all the data, but in the meantime here's the spin and a few extras.

Measurement details: 1m distance, 6.5ms gate. Gear: CSL calibrated Umik-1 and a Fiio K3 DAC. Measurement axis was tweeter height, centerline of speaker (I didn't receive a manual, but this measured significantly better than the tweeter's axis, which is offset and mirrored). On axis is merged with nearfield port and woofer summation at 550Hz, which has been compensated for baffle step. The off-axis bass is simulated by VituixCAD based on the on-axis. This speaker has a high-frequency control knob, which was set to the default '0' setting for this spin.

Nice! Some messiness in the mids and a dome resonance off-axis (it's blocked on-axis due to phase shield, as pointed out to me by the speaker's engineer) but those are about the only notable issues.

Bass is a bit elevated around 100Hz as Harman sometimes does with bookshelves, so you might want to keep some distance from the wall or use EQ if it comes off a little heavy -- for most it should be enjoyable. PIR is particularly impressive for a passive speaker if you ignore above 10kHz. This peaking should not be an issue unless you have a very live and narrow room as the highest frequencies off-axis sound tends to get absorbed/dissipated real fast. There's always that treble knob if you need to tame it.

Harman was kind enough to send me their own spin too. Lo and behold:

You can't ask for much more correlation than that! Glad to see I have at least some idea what I'm doing . Theirs is just a bit better, showing a slightly wider bass rolloff and a little bit nicer mids off axis.

(Side note: this is the first time I've seen 'Horizontal DI' on an official Harman spin. We've discussed on ASR why using that or Horizontal ERDI can be a more useful metric for soundstage performance than the regular DI curve, so I'm glad to see this is indeed a tool Harman uses.)

Copied Harman's data to REW with VituixCAD, and overlaid the on-Axis, PIR and Sound Power against mine.

My PIR is a bit elevated relative to Harman's, perhaps something to do with the measurement distance (1m for me vs at least 2m for Harman), and there's the aforementioned bass difference. But overall I'm happy.

Further investigation showed the most linear axis might actually be a bit lower on the horizontal centerline, in between the tweeter's waveguide and the woofer. In any case, this is the axis I used for the measurement below, plotting the effect of the high-frequency knob at four positions: default (white), max (blue), 12-o'clock (green), and minimum (you guessed it, red).

The default seems to run a little hot, but nonetheless it was my preferred setting (unless using the grille, in which case I preferred it a little higher), despite still being able to hear 20kHz thankyouverymuch.

In any case, that's a much wider range of readily-accessble tone control than you usually get on passive speakers. As the crossover is set fairly low at 1.8kHz, the single knob actually covers quite a wide range of frequencies, letting it act a bit like a tilt control. You're not going to get off the couch to change the treble on each speaker for every song, but it's nice to switch things up every now and then. It's a much-appreciated feature.

As for, you know, the sound: I love these. Soundstage for days, like the L100 classic.

And that's all for now

 

[Valentin R]

Thanks for the review

 

[Valentin R]

Did you ever get the spins for the l100 classic ?

 

[richard12511]

It's been a while! I've had the JBL L82 for some time now, and as far as I know, there are no published measurements for it yet. So here I am =]

An incomplete post for now. Full suite of measurements and interpretations once I've published my review and formatted all the data, but in the meantime here's the spin and a few extras.

Measurement details: 1m distance, 6.5ms gate. Measurement axis was tweeter height, centerline of speaker (I didn't receive a manual, but this measured significantly better than the tweeter's axis, which is offset and mirrored). On axis is merged with nearfield port and woofer summation at 550Hz, which has been compensated for baffle step. The off-axis bass is simulated by VituixCAD based on the on axis. This speaker has a high-frequency control knob, which was set to the default '0' setting for this spin.

View attachment 79111
Nice! Some messiness in the mids and a dome resonance off-axis (it's blocked on-axis due to phase shield, as pointed out to me by the speaker's engineer) but those are about the only notable issues. Bass is a bit elevated around 100Hz in common Harman fashion, so you might want to keep some distance from the wall or use EQ if it comes off a little heavy, but for most it should be enjoyable. PIR is particularly impressive for a passive speaker if you ignore above 10kHz. This peaking should not be an issue unless you have a very live room and narrow room as the highest frequencies off-axis sound tends to get absorbed/dissipated real fast, plus there's always that treble knob.

Harman was kind enough to send me their own spin too. Lo and behold:

View attachment 79109

You can't ask for much more correlation than that! Glad to see I have at least some idea what I'm doing . Theirs is just a bit better, showing a slightly wider bass rolloff and a little bit nicer mids off axis.

(Side note: this is the first time I've seen 'Horizontal DI' on an official Harman spin. We've discussed on ASR why using that or Horizontal ERDI can be a more useful metric for soundstage performance than the regular DI curve, so I'm glad to see this is indeed a tool Harman uses.)

Copied Harman's data to REW with VituixCAD, and overlaid the on-Axis, PIR and Sound Power against mine.

View attachment 79110My PIR is a bit elevated relative to Harman's, perhaps something to do with the measurement distance (1m for me vs at least 2m for Harman), and there's the aforementioned bass difference. But overall I'm happy.

Further investigation showed the most linear axis might actually be a bit lower on the horizontal centerline, in between the tweeter's waveguide and the woofer. It brings up the upper mids a little, though we're splitting hairs at this point. In any case, this is the axis I used for the measurement below, plotting the effect of the high-frequency knob at four positions: default (white), max (blue), 12-o'clock (green), and minimum (you guessed it, red).

View attachment 79112

The default seems to run a little hot, but nonetheless it was my preferred setting (unless using the grille, in which case I preferred it a little higher), despite still being able to hear 20kHz thankyouverymuch.

In any case, that's a much wider range of readily-accessble tone control than you usually get on passive speakers. As the crossover is set fairly low at 1.8kHz, the single knob actually covers quite a wide range of frequencies, letting it act a bit like a tilt control. You're not going to get off the couch to change the treble on each speaker for every song, but it's nice to switch things up every now and then. It's a much-apreciated feature.

As for, you know, the sound: I love these. Soundstage for days, like the L100 classic.

And that's all for now

Wow, that’s incredibly close to the Haran spin! Good job! I wish I could learn to measure like this.

 

[napilopez]

Did you ever get the spins for the l100 classic ?

I did not, though now that I think about it, I don't think I ever asked

Wow, that’s incredibly close to the Haran spin! Good job! I wish I could learn to measure like this.

Thanks! I was particularly surprised by the top octave, which is rarely quite so matchy both on and off-axis. Perhaps CSL calibrates to the same standard as Harman.

Not much to it though - just pointing the microphone at the speaker and make sure there are minimal obstructions to cause reflections within the measurement gate -- easy enough to check in the impulse response (I do my measurements indoors). Hardest part is getting the bass summation right, which is still a work in progress. Luckily I can settle for 'close enough' on that given how much a room modifies bass anyway.

 

[AudioQuestShill]

Thoughts on the jbl 4312g? Have anyone heard these

 

[napilopez]

Sorry, I have not

 

[Valentin R]

Thoughts on the jbl 4312g? Have anyone heard these

this is the 4312SE the G should be very similar if not the same

 

[Biblob]

Did you measure with or without the grille?
These look like very enjoyable speakers.

 

[knownunknown]

newbie here.. would a yamaha as501 be enough for these or would there be too much disparity in "quality"?

edit: smalish room, listening to music on decent, not concert levels

 

[AudioQuestShill]

this is the 4312SE the G should be very similar if not the same
View attachment 79320

That looks better than the L82 to me. Interesting. Might have to give it a listen.

 

[napilopez]

Did you measure with or without the grille?
These look like very enjoyable speakers.

Measured without the grille for the full spin, but I did measure the effect of grille on axis. It does clearly degrade the souind a bit in the presence region but I honestly can't say I noticed much of a difference other than wanting to move the HF knob a little higher with the grille on:

newbie here.. would a yamaha as501 be enough for these or would there be too much disparity in "quality"?

edit: smalish room, listening to music on decent, not concert levels

I'm sure it'd be fine, these speakers don't require much power.

this is the 4312SE the G should be very similar if not the same
View attachment 79320

That looks better than the L82 to me. Interesting. Might have to give it a listen.

White it looks pretty good and I personally tend to like extra energy around 2kHz, It definitely looks worse than the L82 to me, whose only flaw that's likely to be significantly audible is the mess around 1kHz. Keep in mind the scaling of the images, this one is 'squished'. Here it is scaled to match Harman's L82 graph:

vs the L82 again:

While the 4312SE isn't as messy as the L82 around 1kHz, it still has a wide-Q scoop in the region which is likely to be just as audible if not more so. It also shows a lack of energy around 200Hz, excess energy at 2kHz (although this is something I personally tend to enjoy!), and more mising energy again around 3-4kHz. I'm not sure to what extent the 4312SE's issues can be fixed via its knobs, but I'm guessing not much.

The 4312SE doesn't look that bad, but it's clear to me the L82 is the more neutral speaker. The predicted in-room response is among the best i've measured.

 

[AudioQuestShill]

Great response. The first thing i noticed was the 2khz you mentioned in your post. I do wonder tho, while the 4312Se should be similar to the 4312g but perhaps there are differrnces in measurements. Does Harman has publish measurents for the 4312g?

 

[knownunknown]

do you guys feel they are overpriced at roughly 2500 $ ?

 

[napilopez]

Okay, I'm going to breaking down the L82's directivity a lot. Feel free to just look at the graphs, but I've written this essay because, there are some interesting things happening directivity-wise.

Like the L100 Classic before it, the L82 have some of the best imaging I've heard from a speaker in my home. How much of that is the speaker vs it's compatibility with my room is something you'll have to assess on your own. Speaking purely subjectively and based on recollection other speakers I would rank it's soundstage performance above anything I've reviewed at home other than the L100(a very similar spatial presentation) and D&D 8C(a very different spatial presentation).

I do not know if the measurements really bear this out, but we can at least talk a bit about what's going on.

IMO, there are two ways of making a great speaker: 1) do everything 'right' to minimize flaws in any aspect of the measurements. Think Genelec, Neuman, KEF, and Revel. Or 2) Start with a good speaker and balance out the flaws to make the whole greater than the sum of its parts. This L82 appears to be a case of the latter, as we'll see in our investigation of directivity.

Some comments on positioning

As mentioned, the tweeters are offset, but unlike the L100 classic, they are mirrored. This basically means you are getting two speakers in one: the soundstage changes depending on whether the tweeters are on the inside or outside. JBL does not mark the speakers as left and right, nor does it give a suggestion in the manual. I see one JBL presenter at an italian event on YouTube with a JBL presentation showing the tweeters on the outside, but I suspect JBL wants you to experiment and see what sounds best in your home.

The manual for the 4312SE, which also has unmarked offset tweeters, does say something about placement:

The JBL 4312SE is sold as mirror-image pair of loudspeakers with one having the tweeter on the left side and the other having the tweeter on the right side, yet neither one is marked or defined as a “LEFT” or “RIGHT” channel loudspeaker. Which one should be used for the left channel and which one should be used for the right channel will depend on a combination of factors including the listening distance from the speakers, the width of the room, acoustic reflectivity of the room, and horizontal versus vertical positioning of the loudspeaker.

It is typically best to position the loudspeakers to create a triangle of three equal sides when measuring the distances between the tweeters in each speaker and the distance from the listener to each tweeter. In smaller rooms or instances where the listening position is relatively close to the loudspeakers, this will usually result in the tweeters being positioned to the inside of the listening triangle. This positioning can also be desirable in a more acoustically reflective room or when the speakers are placed on a shelf or close to a side wall.

The illustrations in both manuals show the speaker without toe-in, and suggest it's only necessary if your setup is very wide. (The L100 says the same thing verbatim, so this may just be standard copy).

"For best results, place the speakers 6–8 feet (1.8-2.4m) apart. If you set the speakers farther apart than this, angle them toward the listening position. The speakers will produce the most accurate stereo soundstage when the angle between the listener and the speakers is between 40 and 60 degrees."

Measurements

I personally believe that when measuring speakers, I should investigate the optimal listening axis, especially when not specified by the manufacturer. My ultimate goal is to provide the reader with the best listening experience I can. In this case

When I first measured the speakers, I assumed measuring at the tweeter, as is standard, would be ideal. This, however, didn't lead to a very nice on-axis graph. Unfortunately, I seem to have not saved my tweeter axis measurement, but it ended up very much like the +10 degree measurement, which roughly realigned the mic with the tweeter:

So instead I used the centerline of the speaker at tweeter height as the measurement axis:

In any case, using the centerline was more convenient for me, as it was easier to balance the speaker on the stand =]

Because of the offset tweeter, you have two quite different set of measurements, as is visible at a glance from the horizontal polar graph(normalized to the center axis):

Top half is on the 'close' side of the tweeter(towards the right of the centerline in the image above), while bottom covers the 'far' side. As you can see, the far side is overall prettier, though the near side is a teensy bit wider.

As many of you know, I have a clearly defined preference for wider directivity within the 2-10kHz range and the L82 fall under the wide directivity catergory for me.

To see how the unevenness in the midrange directivity balances out in practice, let's look at the horizontal components of the early reflections curve:

You can see how despite the asymmetrical response, both sides average into something very close to the listening window. The horizontal ERDI curve is almost perfect, and it shows in how well the speakers image.

However, diving deeper into this rabbit hole, we quickly realize that in a mirrored asymmetrical speaker, your decision of having the tweeters on the outside or inside is going to have a major impact on which portion of the horizontal radiation is heard more loudly.

To investigate this we can divide the sidewall component of the ER curve, which is an average of ±40,50,60,70,80 degrees horizontal, into its positive and negative halves.

You can imagine how having the tweeters on the inside would make the 'far side' reflection (green) louder. Having tweeters on the outside would make the 'close side' reflection louder(orange). You can further imagine that this is more true if your speakers are very close to the sidewalls and you have a wide setup.

At first glance the far side reflection(tweeters inside) is closer in contour to the listening window . In practice, however, you'll have to experiment with your own room balance.

I had a clear preference for having the tweeters on the outside in my home (a 13-ft/4m wide room, with the speakers about 8 feet(~2.4m) apart/about 2.5 feet(~0.75m) from the sidewalls). This is regardless of whether I tried to match the location of the tweeters.

The most notable effect of having the tweeters on the outside was a wider soundstage. This is perhaps simply because in a relatively narrow setup, moving the tweeter outward and closer to the sidewall few inches is enough to significantly widen the soundstage. This also surprised me because I tend to prefer having excess energy around 2kHz. Whatever timbral degradation there may have been by having the tweeter on the outside was more than balanced out by the wider soundstage. If anything, I noted preferring the timbre with the tweeters on the outside too, prior to having made measurements.

Speculation time: In an effort to investigate why, I attempted a rudimentary calculation of the SPL difference between the close wall reflection and the far wall reflection in my home. Based on the difference in path length, it seems to be about 4 dB. If I average the sidewall reflection taking this into account, then I can come up with two alternate calculations for the sidewall reflections depending on tweeter placement(updated, previous version of this image had the opposite labels.

I'm making lots of assumptions, but perhaps having the tweeters on the outside leads to more neutral reflections overall, even if a bit more dissimilar from the direct sound around 1-2kHz. Whichever curve I choose for calculating the total horizontal and total early reflections, however, the difference is quite minimal, no more than a dB in any region.

You should also consider that if using the speaker with no toe-in, as implied by the manual, your direct sound will be different as well. In my setup, no toe in tweeters on the outside means I'm sitting at roughly -20 degrees from the reference point. And vice versa:

Breaking it down further, here are plots 0-90 degree plots for the close side:

Same but normalized to the reference axis:

You can see there is a significant dip at 2kHz and 1Khz. From 3K to 10k, the measurements are mostly pristine though.

And then on the far side of the tweeter:

Normalized:

And at last we get to the vertical measurements. You do not want to be above far above tweeter height.

However, you can see being 5 or 10 degrees below the reference axis hardly makes a difference and might even improve the response. This is likely a reason the official stand for these speakers is tilted upwards -- this ensures you are unlikely to be above the tweeter axis, even when standing up. It also helps a bit that the speakers are taller than normal, if using a normal stand.

On the plus side, the floor and ceiling reflections are relatively well-controlled and balance eachother very well, ensuring that vertical reflections have a minimal effect on timbre in a typical room:

Finally, the polar depiction, normalized again to the on-axis:

And there you have it: one of my longest forum posts, talking solely about the directivity of a single speaker. You can see why I'm so particular about analyzing the directivity of a speaker before considering other factors of its performance like distortion. I could go longer.

The L82 is a speaker that balances out its flaws in a way that yields an impressive whole. A predicted in-room response that challenges some of the best speakers we've seen, and a relative lack of resonances except for around 1k (maybe, Harman's doesn't show this as a resonance). More importantly to me, personally, is that JBL Synthesis once again created one of the most enjoyable speakers with some of the most pleasing imaging I've heard, with some nice ability for customization (tweeter placement and HF knob) to boot.

As always, your mileage may vary, but I can happily recommend these. They are not the most technically impressive speaker I've seen, and the flaws in the measurements do suggest there may be more variation in atypical setups than, say, a genelec or neumann. However based on the combination of my listening impressions, measurements that are overall good, and a carefully balancing act turning them into something great, I would personally buy the L82 over anything else I've reviewed sub $3,000.

 

[daftcombo]

Hi!
Great review.
Would distortion measurements be possible?

 

[napilopez]

Hi!
Great review.
Would distortion measurements be possible?

Thanks! And unfortunately not. I decided early on I would do FR, directivity and nothing else. I do not personally care about distortion unless I'm sure I'm hearing it... and I'd rather not start caring .

Not that I don't appreciate others wanting access to that data, but I'd rather limit my scope to the two things I know matter most considering the extremely limited time I can spend measuring speakers.

Maybe someday though. But the L82 specifically are on a truck on their way back to Harman now (he says as a tear streams down his cheek)

 

[daftcombo]

Thanks! And unfortunately not. I decided early on I would do FR, directivity and nothing else. I do not personally care about distortion unless I'm sure I'm hearing it... and I'd rather not start caring .

Not that I don't appreciate others wanting access to that data, but I'd rather limit my scope to the two things I know matter most considering the extremely limited time I can spend measuring speakers.

Maybe someday though. But the L82 specifically are on a truck on their way back to Harman now (he says as a tear streams down his cheek)

I understand. Your sentence "I would personally buy the L82 over anything else I've reviewed sub $3,000." rings a bell and I would have liked to compare disto to the figures of Revel M106 and Genelec 8030 for instance.

 

[AudioQuestShill]

How would the L82 compared to the Wharfedale Linton 85th edition?

Here are some measurements from an external site

Link

 

[watchnerd]

do you guys feel they are overpriced at roughly 2500 $ ?

Yes.

For the same money, you could get a Revel M106.

But I use subs and that changes things.