JBL 708P Review (Professional Monitor)

[FrantzM]

Hi

Competition to this would be the Neuman KH310... Price in the same ballpark and better measurements. You lose a lot of functionality, since the Neumann has only analog input... but it has no port and is 3-way. I would favor the Neumann
Either one could be endgame for many (I, included). With DRC and a pair of subwoofers ... In a mid-sized room? Heaven!

 

[Kachda]

Hi
Either one could be endgame for many (I, included). With DRC and a pair of subwoofers ... In a mid-sized room? Heaven!

Especially when the wife leaves you because they are so darn ugly

 

[Pio]

Especially when the wife leaves you because they are so darn ugly

So can we leave our wives if we don’t like their shoes? Asking for a friend...

 

[Bugal1998]

Yeah, looking back at the JBL LSR308P MkII review, it's clear that JBL might be eating its own lunch with that model at an 85% discount versus the 708P. The 308P MkII has smoother in-room response and better directivity, and the only sacrifice appears to be a bit more distortion.

Owning both series of speakers (and the M2) I've told a number of folks looking for speakers that the 7 series is a hard sell against the 3 series if you don't need the output and extra resolution (readily apparent in A/B comparisons). In my subjective experience, within its limits the 3 series is more enjoyable on less than great recordings for casual listeners just wanting a nice speaker.

It's also apparent during A/B listening that the 7 series is the more refined and capable speaker vs the 3 series. Amir made a similar observation with his 305 vs 705 comparisons.

 

[Deleted member 2944]

Sorry this is incorrect. Please see again
Overley, J.P.: Energy Distribution in Music, IRE Transactions on Audio, 09-10, 1956

View attachment 110090

Average peak energy for most music genres remains at maximum up to 2400 Hz and 4800 Hz. So you need the amp with same output voltage level with 1.7kHz crossover frequency, provided the drivers have the same sensitivity. Of course only in case that you do not like clipping for some reason.

Uh, sorry, no. About 350Hz defines the 50/50 power split.
https://www.sound-au.com/bi-amp.htm#power_dist

I've done some practical experiments on this using normal program material, and approximately 350-400Hz is correct.

And remember, in this case (708p), the drivers do not have equal sensitivity.
I've looked at the electrical drive levels in this particular speaker, and it's way lower on the tweeter.

Dave.

 

[YSC]

According to the manual, -3 dB is already reached at 25 kHz. View attachment 110080

Measurements by Sound and Recording of the 705p have 22.6 kHz already down 6 dB, while 20 kHz seems to already be about 3 dB down.

Source: https://www.soundandrecording.de/equipment/jbl-705p-nahfeldmonitor-im-test/

is that room mode or something? the huge dip at~780hz looked nasty

 

[infinitesymphony]

FR does look a tiny bit better with the 308p, but I have to disagree about the directivity. Horizontal beamwidth is (imo) the most important graph to judge directivity performance. Looking at the two side by side, the 308p seems to narrow(starting at 1kHz?), widen and then narrow a bit more. The 708 looks like a more straight beam imo. The 308 is a bit wider, though, which may be a good thing for the majority. The 708 also provides a bit more max output, and I'd say the distortion difference is more than "a bit" . 308p is definitely the better value, though, even at non-sale prices.

Also, I think the output differences are larger than what the official specs say. I own the 308p and it's starts sounding "too loud" well before by ears would usually give up. I don't own the 708p, but I've heard it, and I didn't get that sensation. It (subjectively) got loud enough to fully satisfy me.

Good points, especially about the consistency of directivity over frequency range. It definitely seems like a question of how much volume you need because the proportion of distortion is so highly correlated to SPL. I rarely hit 86 dB RMS near-field, so something like the 308P MkII or iLoud MTM might be suitable for me where the 708P could be a better fit for others.

The 708P also has some integration features in its favor that I don't think have been discussed yet, especially if the speakers are used in a multichannel or distributed audio system. They have Harman HiQnet via RJ45 which should assist with communication and configuration, and they include separate room delay and lip sync delay settings which could be useful in a reasonably well-sized A/V production suite.

 

[pma]

I would like to see better S/N parameters, especially of the woofer section. I wonder why those powered speakers are usually noisy. At least it seems they do not use class D for the tweeter (appreciated), from their website specs. Anyone measured resonances of the 12mm plywood case? I am still not sure that I would want this as a hifi speaker.

Specs in the manual

 

[Deleted member 2944]

For those that might be interested, this is what the drive level to the 708p woofer looks like:
I have the tweeter plot here on my computer somewhere as well, but can't seem to find it right now.

Dave.

 

[ctrl]

JBL claim to have 2 channel amplification for these speakers with a 250W amplifier for the LF and a 250W amplifier for the HF. Clearly they understand the importance of having equal capability power delivery across the audible spectrum, unlike many other companies who economise on the HF amps. Not that a single tweeter compression driver voicecoil could absorb 1/4kW for long...

Can you explain why it is important? I don't understand why a tweeter should ever need 250W.

Because the short peaks are not impossible. And where is the crossover frequency? At 1.7kHz!! You will have full energy up to 5kHz. It seems to me many of you guys just do not understand what you speak about.

I don't know if the comments were meant ironically, so a few thoughts on that.

The 708P has a compression driver with waveguide. This thing should easily deliver 100dBSPL (100dB/1W/1m).
If the amplifier for the tweeter would deliver only 50W of power (THD <=1%), a maximum sound pressure of 100 + 10*log50 = 117dB would result.

Therefore, the 250W amplifier power for the compression driver is total overkill and completely unnecessary. But Class D amplifier power can be had cheaply, so why develop another power amplifier.

The maximum peak SPL of the speaker is given in the specification as 114dB, so 50W would still be sufficient for a driver/waveguide combination with only 97dBSPL.

 

[respice finem]

It's not about you hearing 20kHz.

It's about equipment that can accurately describe and reproduce any waveform within the universally accepted audible spectrum in a linear fashion.

Whether you can hear it or not is irrelevant. Do you adjust the system for each member of your family or friends based on their auditory abilities? Do I adjust the tweeter output for my teenage boys vs me? No, of course not.

This JBL 708P appears to be a speaker worthy of auditioning and consideration.

You clearly have a point about accuracy/linearity, but it's not all quite that simple IMHO.
There is no "universally accepted" consensus as to how much "spectrum overkill" would be necessary for this. Many highly rated speakers don't try to confuse the bats Sorry I'm a "natural born skeptic" and always prefer proven things to "facts by manufacturers" - they don't have to be wrong, but they can. As long as this extra high frequency spectrum remains clean (not picking up "garbage" from mediocre AV receivers and such), there is hardly an argument against it, I admit. And yes, the 708P is worth considering, I never intended to state the opposite and it's on my "must hear" shortlist.
Do I adjust the system for family / friends? Yes I do, regularly, both for music and movies. Being aware of my gradually fading hearing of high frequencies, I prefer a flat "room curve" when hearing alone with loudspeakers, or a slight treble emphasis with headphones, because it gives me back the ability to hear treble detail. I'm neither a musician nor a producer, and thus, my main objective is to enjoy music, and what I don't hear any more I can't enjoy, time waits for no one... The younger family members/guests will prefer a slight treble rolloff, which is only a push of a button or a mouse klick away. I think every audio enthusiast over 50 years of age should perform an audiometry every few years, this is really an eye opener, and dirt cheap compared to new equipment, that is not going to make one younger either...

 

[jeroboam]

Just compared this with the Tannoy xt6 distortion at 96db in the 200 to 2k range and while the Tannoy looks a bit worse it is not significantly so. As the Tannoy was severely criticized I wonder what the explanation for the difference in the ratings are. I must admit that I am a complete philistine in understanding speaker measurements so hopefully someone can put me right thanks.

I know that the JBL is an expensive powered monitor compared to a cheapish passive so is my question therefore too risible to merit a response ?.

 

[YSC]

I know that the JBL is an expensive powered monitor compared to a cheapish passive so is my question therefore too risible to merit a response ?.

I think in that sense the Tannoy isn't ranked down by the distortion at 96db, but mostly by it's FR, personally it's only the FR that matters before you go into the level where distortion kicks in, so if you don't have a nice smooth FR to start with the score won't be high

 

[Ron Texas]

Wow, 5 pages of response in about half a day. It shows how much interest there is in this product and in high quality active monitors in general.

@amirm I ask when you come up with recommended EQ adjustments are these calculated by a computer program, or do you "eyeball" the filters? Thank you for another great review.

 

[infinitesymphony]

I know that the JBL is an expensive powered monitor compared to a cheapish passive so is my question therefore too risible to merit a response ?.

I think in that sense the Tannoy isn't ranked down by the distortion at 96db, but mostly by it's FR, personally it's only the FR that matters before you go into the level where distortion kicks in, so if you don't have a nice smooth FR to start with the score won't be high

Yes, the biggest preference score dings for the Tannoy XT6 are against the uneven frequency response and treble tilt, which affect the predicted in-room response by flattening the bass to treble slope. The directivity is not bad but is also uneven, especially at 2.5 KHz where there appears to be a resonance that is causing phase cancellation (looking at the waterfall). There are also other resonances, and while not scored, the distortion is not great either.

 

[jeroboam]

I think in that sense the Tannoy isn't ranked down by the distortion at 96db, but mostly by it's FR, personally it's only the FR that matters before you go into the level where distortion kicks in, so if you don't have a nice smooth FR to start with the score won't be high

Thank you YSC for responding and I've learned something new.

 

[617]

Wow, 5 pages of response in about half a day. It shows how much interest there is in this product and in high quality active monitors in general.

@amirm I ask when you come up with recommended EQ adjustments are these calculated by a computer program, or do you "eyeball" the filters? Thank you for another great review.

Yeah if you want the best in sound reproduction a pair of powered full range speakers are the easiest route. $3600 dollars and a DAC and you have extremely high quality sound reproduction with decent bass, high output and some room integration flexibility. Ultimately this is a faster an easier route to high end sound than headphones or small passive speakers.

 

[dfuller]

Hi

Competition to this would be the Neuman KH310... Price in the same ballpark and better measurements. You lose a lot of functionality, since the Neumann has only analog input... but it has no port and is 3-way. I would favor the Neumann
Either one could be endgame for many (I, included). With DRC and a pair of subwoofers ... In a mid-sized room? Heaven!

The KH310 is straight up better in almost every single way, IMO. No port for all the resonance messiness they can cause, the distortion everywhere but the very bottom end is better, no narrow interference dips that seem to be present in the 700 series... but they're about $800 more per pair ($4400/pr new vs $3600/pr). At around $4000/pr, you're spoiled for stellar options though - between Barefoot's Footprint offerings, the KH310s, the 708s, etc etc.

is that room mode or something? the huge dip at~780hz looked nasty

I was wondering about that too, but it seems to be present in Amir's measurements too of both the 705 and 708.

Yeah if you want the best in sound reproduction a pair of powered full range speakers are the easiest route. $3600 dollars and a DAC and you have extremely high quality sound reproduction with decent bass, high output and some room integration flexibility. Ultimately this is a faster an easier route to high end sound than headphones or small passive speakers.

Simpler and easier to set up, too - no amp to deal with, no extra cables from amp to speaker... Just an overall better setup.

 

[617]

Hi

Competition to this would be the Neuman KH310... Price in the same ballpark and better measurements. You lose a lot of functionality, since the Neumann has only analog input... but it has no port and is 3-way. I would favor the Neumann
Either one could be endgame for many (I, included). With DRC and a pair of subwoofers ... In a mid-sized room? Heaven!

The KH310 is straight up better in almost every single way, IMO. No port for all the resonance messiness they can cause, the distortion everywhere but the very bottom end is better, no narrow interference dips that seem to be present in the 700 series... but they're about $800 more per pair ($4400/pr new vs $3600/pr). At around $4000/pr, you're spoiled for stellar options though - between Barefoot's Footprint offerings, the KH310s, the 708s, etc etc.

I'm going to reserve judgement on the Barefoot offerings until I see ASR measurements. We're also missing Kii and D&D and the higher end ADAM models, although they're pretty pricey. The most direct competition to the 708 is probably the Genelec 8050B, which retails for 3600 a pair. We've yet to see a Genelec that isn't excellent, but I suspect the bass and dynamic quality of the 708 are better.

The vertical orientation of the 708, lower price and smoother directivity edge it out for me against the Neumann but obviously both are excellent.

 

[q3cpma]

Not bad, but I'm not sure people know JBL's pricing in Europe. Here, it's 2100€ new vs 1750€ for the KH310 and 1800€ for the 8350A. Which have better performances (distorsion, port and on-axis FR) with less known reliability issues.
Again, not to say that this is a bad speaker, but the competition is simply too good at that price point.