JBL 708P Review (Professional Monitor)

[richard12511]

This may help from my review of 8341A:



Distortion measurements are not meant to show max SPL.

8351 has this same problem at 3.5m if I try to run it full range.

 

[Pearljam5000]

8351 has this same problem at 3.5m if I try to run it full range.

So they don't get loud at all?
Pretty disappointing especially at that price

 

[richard12511]

So they don't get loud at all?
Pretty disappointing especially at that price

No, I definitely wouldn't say they "don't get loud at all". What I meant by that is they don't play music with deep bass loud enough to satisfy me sitting at a 3.5m distance. My main room is also open to the kitchen and entryway.

On music with no deep bass, they get almost rock concert loud. Louder than I listen. Also, with the RS2s helping them, I've seen over 113dB(with deep bass) at the listening position with *no* red lights of despair.

*Edit: Btw, I disagree with Amir's score for the 8341. I think he was judging it by a metric it's not entirely designed for. IMO deep bass is what limits these speakers, but I also think external subs are generally required anyway for top tier bass, regardless of the speakers. IMO, these speakers are about as good as it gets with subwoofer help, but full range, there are better(bigger) options for not much more.

 

[Sir Sanders Zingmore]

US $1,799 each.

AUD 4,800 each

https://derringers.com.au/jbl-708p-7-series-8-studio-monitor-each

 

[LTig]

I would also love to see IMD, but from what I've read, it's a time consuming measurement, or perhaps requires a different module for the Klippel?

You could do a multitone measurement like Sound & Recording does.

 

[okok]

overpriced right

dyna lyd48 why not

 

[dfuller]

overpriced right

dyna lyd48 why not

LYD48 has considerably less amplifier than the 708 (50/80/80 vs 250/250) and isn't waveguided at all which could create some directivity weirdness around the crossovers. That said, for nearfield, I'd probably prefer it, as I find 3 ways to generally be superior to even the best 2 ways.

 

[maxxevv]

AUD 4,800 each

https://derringers.com.au/jbl-708p-7-series-8-studio-monitor-each

Order a pair to be sent to a hotel in Los Angles, buy a flight ticket to LA to collect and fly back. I think you will still come out about AUD$2000 total less.

 

[ROOSKIE]

No, I definitely wouldn't say they "don't get loud at all". What I meant by that is they don't play music with deep bass loud enough to satisfy me sitting at a 3.5m distance. My main room is also open to the kitchen and entryway.

On music with no deep bass, they get almost rock concert loud. Louder than I listen. Also, with the RS2s helping them, I've seen over 113dB at the listening position with red lights of despair.

*Edit: Btw, I disagree with Amir's score for the 8341. I think he was judging it by a metric it's not entirely designed for. IMO deep bass is what limits these speakers, but I also think external subs are generally required anyway for top tier bass, regardless of the speakers. IMO, these speakers are about as good as it gets with subwoofer help, but full range, there are better(bigger) options for not much more.

I am glad you are pointing this out for folks.
It just makes no sense to expect room filling low bass (40-55hrz and down below) from any set of speakers that does not have either several (larger) deep bass drivers or some sort of independent powered low end.
If I spend $3600 on excellent 2 way speakers the last thing I want to have any money spent on the design getting them to double as "subs". These and all high end monitors deserve a high-pass and generous sub reinforcement & wish all the design was focused on was performance paired with subs.
I actually ask JBl (and other manufactures) to skip the port & let the designs be useful sealed down to 60-65hrz with no port issues, knowing that a sub is required anyway. Let a proper 10,12,15,18 woofer (or even an high excursion 8 designed to be tuned low)handle below 55hrz and free than design up.
Problem is people see the 8" and 10"(Neumann)drivers in the monitor and think bass! Rather than dynamics, high output SPL's with lower HD and intermodular distortion and the other goodies that a larger driver can provide over a 5 or 6 inch woofer.

You could do a multitone measurement like Sound & Recording does.

That would at least point to the direction IMD takes in the speaker.
Really there are so many frequency being played simultaneously in music that it is hard to test in a real way.
Erin's audio corner does test this sometimes and it is sorta informative.

Interesting, since the KH310 has less distortion at 96 dB SPL than the 708p.

Most of the JBL Harmonic distortion is 2nd order and not really that high and thus extremely hard to hear.
Remember 2nd order is just 1 octave higher and thus very similar in tone - especially hard to hear in bass as that sorta just ultimately adds extra bass.
3rd order and higher are very, very low. World class low. The tweeter is truly fantastic. Loaded compression tweets seem to have elevated 2nd order harmonics - I don't know why. I use 2 pairs and have been researching several more for future DIY plans. They are much less likely to an audible issue than a mental tic. That appears to be a fantastic tweeter in my book. It is also likely to have much less IMD than a conventional tweeter at the volumes of normal and high playback. Also the tweeter likely with have much less stored energy again as it is barely working up a sweat even at 100db. That tweeter is capable of 120db SPL.

In any case man it would be hard not to want all of the these $4kish USD, offers from JBL, Neumann and Genelec. Truly outstanding overall designs.
I also think they all look very, very cool. I'd have no problem with them my Urban living room at all. I prefer the JBL's look with the other two a close second. While I like furniture style audio as well, I really like gear that looks like gear - especially intense looking gear.

 

[amirm]

You could do a multitone measurement like Sound & Recording does.

I ran this for a while. Here is an example:

It is extremely hard to interpret because the frequency response and hence the peaks change. And with it, so does intermodulation. High noise floor also masks a lot.

 

[thewas]

It is extremely hard to interpret because the frequency response and hence the peaks change. And with it, so does intermodulation. High noise floor also masks a lot.

But that's not a problem of the method but that most people like you and I measure it in normal reflective rooms. Interpretation isn't also easy on first sight but it can quite well show relative differences like below:

Source and more: https://en-de.neumann.com/product_files/7950/download

 

[test1223]

Max spl
@thewas @richard12511 the capability of playing louder without major distortion as @amirm already wrote is not displayed in the measurements. But never the less you can see that the neumann 320 has about 100% distortion @96dB spl in the Bass. So it will sound distorted. In a multi tone test you would see this much more easily, since the harmonics alone will cause a lot of trouble. The jbl might sound a bit stressed @96 dB spl but it is quite okay /good since the masking of distortion at these higher level will also shift towards can't be perceived. As I said earlier hd is harder to interpret and you probably don't see all the major problems at all.

Idm measurements
@amirm yes the peaks change if you use a signal which has the same distance in Hz. It is an indication how it will sound with music which uses a wide frequency range. A harder signal has changing frequency distances so you can also see the harmonics better. But this doesn't represent a music signal as much. As you said without a special room, measuring bass distortion in imd is no good, since the environmental noise is changing and relativly high.
There should be some algorithms which will increase the snr for imd measurements estimation in noisy environmen? One other suggestions would be to mark the areas in the graph which are unreliable.

 

[thewas]

@thewas @richard12511 the capability of playing louder without major distortion as @amirm already wrote is not displayed in the measurements.

The 96 dB measurements of both clearly show that the 708 is more "comfortable" (low distorting) at the region below 70 Hz while above the 310 is superior, so what plays louder depends on the frequency content of the music heard.

In a multi tone test you would see this much more easily, since the harmonics alone will cause a lot of trouble. The jbl might sound a bit stressed @96 dB spl but it is quite okay /good since the masking of distortion at these higher level will also shift towards can't be perceived. As I said earlier hd is harder to interpret and you probably don't see all the major problems at all.

Again, when woofers of both are pushed at high SPLs like above shown 96dB the woofer of the Neumann will most probably really show higher IMD like you say, but being a 3-way the high IMD will limited to the bass (650 Hz crossover frequency) and won't muddy the much more audible and important mids like it will on the 708 (1700 Hz crossover frequency). It seems also that Amir noticed that, commenting with "non happy at this level" on the 708P measurement.
Its a shame that Sound & Recording has only measured the 705p till now as we would have a nice comparative IMD plot to the one of the KH310 or the already measured Genelec 3-ways.

 

[amirm]

But that's not a problem of the method but that most people like you and I measure it in normal reflective rooms. Interpretation isn't also easy on first sight but it can quite well show relative differences like below:

And you couldn't show those differences using THD?

 

[thewas]

And you couldn't show those differences using THD?

Unfortunately while a higher HD usually means also higher IMD, IMD does not only depend on HD so while its an indicator, its not enough.
For example at above shown Neumann IMD measurements, the shown 2-way has very similar and relatively low HD at mids to the comparative 3-way, but its IMD rise higher at the multitone signal, (it was a slide at a presentation at a Neumann presentation at their HQ which showed us why bothering with 3-way when 2-way can also have relatively low HD)

 

[test1223]

Yes hd very often shows not all the problems. Imd is a good addition and provides a better overall statement of the perceived none linear behavior.

@thewas the frequency content of almost any music has the most power in the lower frequencies and the bass distortion of the jbl will be relatively okay until about 104dB spl. The neumann simply can not play back music this loud. Your interpretation of the implications and comparison of distortions 2kHz -35dB vs. 50Hz -0dB is also wrong. The second implies that the speaker is at its execution limits. Which is not good at all. You hear the difference easily. So did Amir in the test....

 

[Juhazi]

Just a remark - ability to play loud well above 100dB is just one feature. At home for typical hifi listening we don't need that. But for HT or PA or someone addicted to unhealthy loud listening spl, one must choose the loudspeaker - amplifier system accordingly.

I have noticed that Amir wants speakers and headphones to play loud with elevated bass, and this reflects to his rating with panthers. On-axis response smoothness and directivity ratings are not enough either, the evaluator must dig deeper and be open with his predictions and preferences. This is why we must study every "test" with or without measurements critically and reflect the verdict to reviewrs's preferences! And then adjust that to your own predictions and preferences and purpose of use.

Regarding the high price of JBL 70x series or alike, we must remember that they include dsp and network, they are ready for PA installations in conference rooms and mid-size HT, professional installations. 8 series Genelecs are meant for near-midfield monitoring, not for PA.

 

[LTig]

High noise floor also masks a lot.

If the noise is stochastic you can reduce it by averaging. Don't know whether this applies to room noise. Might be worth a try.

 

[thewas]

@thewas the frequency content of almost any music has the most power in the lower frequencies and the bass distortion of the jbl will be relatively okay until about 104dB spl.

Most music does not have the most power below 50-60 Hz where the Neumanns distortions starts rising above the JBL one, for example below statistic of the max level found in several tracks (red is the max and blue is the average):

And again, the 310 cannot play deep bass so loud as the 708 can, but the 708 will sound already more muddy due to high HD and especially IMD in the mids.

Your interpretation of the implications and comparison of distortions 2kHz -35dB vs. 50Hz -0dB is also wrong. The second implies that the speaker is at its execution limits. Which is not good at all. You hear the difference easily. So did Amir in the test....

You hear also the higher IMD in the mids, what also Amir did and commented with "not happy" but we are repeating ourselves now and only an IMD measurement of both will finally reveal the truth.

 

[Absolute]

Just a remark - ability to play loud well above 100dB is just one feature. At home for typical hifi listening we don't need that. But for HT or PA or someone addicted to unhealthy loud listening spl, one must choose the loudspeaker - amplifier system accordingly.

I have noticed that Amir wants speakers and headphones to play loud with elevated bass, and this reflects to his rating with panthers. On-axis response smoothness and directivity ratings are not enough either, the evaluator must dig deeper and be open with his predictions and preferences. This is why we must study every "test" with or without measurements critically and reflect the verdict to reviewrs's preferences! And then adjust that to your own predictions and preferences and purpose of use.

Regarding the high price of JBL 70x series or alike, we must remember that they include dsp and network, they are ready for PA installations in conference rooms and mid-size HT, professional installations. 8 series Genelecs are meant for near-midfield monitoring, not for PA.

I think the +100 dB ability is more important than we intuitively might think. If we aim for +20 dB headroom for transients, that's 80 db averaged.
In a modest sized listening room I don't feel 80 dB is particularly loud.
@mitchco have written before that there's an "industry standard" for mixing (mastering?) with calibrated 83 dB SPL that is often used, which is important information for accurate tonal balance during playback as well.
Taking IMD into consideration I believe it's a bad thing to have all the transient peaks riddled with additional tones, and I must say I'm a little taken aback with this forum's tendency to declare petite speakers as top class when they're audibly not sufficient for realistic use in normal conditions.

Amir wants speakers that play loud enough, sure, but is that because he likes music loud? Can it be because he listens in mono? For me I feel music sounds louder in stereo than the same spl in mono, likely because you get enveloped in a soundstage.
It could be that he just likes the music to sound realistic in tonality and without distorting transient peaks, and 83 dB averaged from a couple of meters distance in mono is louder than most of these little boxes can effortlessly reproduce.

I really wish the IMD measurements back, @amirm ! THis is the only readily available place where that information can (could) be found as of now.