JBL 708P Review (Professional Monitor)

[Tom C]

Subwoofer integration, to be sure. It's a process I'm feeling my way through, gradually. Quite frankly, I find the prospect daunting. Currently using single sub. no correction for now. Used crossover of 40 Hz from the mains, and 120Hz for the LFE channel, as a first stab at LFE+mains.
The built-in AVR automated correction is Audyssy (Denon x3600h). Just trying to understand capabilities and limitations of the individual components themselves, before adding layers of complexity, and maybe changing some things out. From what I have so far, I'm thinking the extra output from each main would be an improvement, and allow the use of 705 for height. I'm OK if the improvement in 708 over 705 is marginal and not dramatic, but as you point out, 7dB is nothing to sneeze at. Now that I think about it, for just a little less $ per channel, I could have a sub on each of LCR for true full range, and maybe stick one or two at the back of the room for mode control. That'd take up a lot of space, though.
My local dealer who is handling the room remodel wants to put in Revel in-ceiling for the Atmos heights. Guess I could go with that and stick with the 705's.

 

[audio2920]

I haven’t graduated to atmos yet, but I have 705p x 7 and a Rhythmik F18 in a 7.1 setup. Very cool. To my ear, sounds like a movie should.

I'm not brining anything new to that party here, but this is 100% my impression of the 7-series too. I've been mixing movies on JBL ScreenArray speakers (or similar, all of varying quality...) for decades, and when I first heard the 7-series and I was like "Yes, this sounds how a movie should sound!"

It's like a small cinema rather than a big hi-fi. Maybe I'm just used to "hifi" with more scoop in the mids than it should really have. Or maybe the knowledge they're using a compression driver and "horn" biases my assessment. Or maybe it really does somehow give them that "immediacy" and "throw" similar to cinema systems? I dunno. Whatever, I wouldn't hesitate to use 7-series for a small to medium sized home theater. (Except if it needed more SPL handling than the 708 can offer.)

 

[jhaider]

Subwoofer integration, to be sure. It's a process I'm feeling my way through, gradually. Quite frankly, I find the prospect daunting.

Don't worry - it's tedious but not that daunting. Audyssey does a credible job of integrating up to two subwoofers. See here: https://hometheaterhifi.com/reviews...rantz-av7702-surround-sound-processor-review/

Note this processor predated the iOS Audyssey app. You really need the iOS app to optimize use of Audyssey. The technology is good but the target curve is not.

Currently using single sub. no correction for now. Used crossover of 40 Hz from the mains, and 120Hz for the LFE channel, as a first stab at LFE+mains.

That is too low for any installation I can conceive of. The only exception might be if the sub is one of those bad old 1990s units using a very long stroke motor with no inductance control. Those don't play high enough cleanly enough, so are best used just for that bottom octave. Actually best thrown away, but I digress.

Mains/subs crossover is better set by what works in the room, not the lower corner of the mains' FR. I would raise yours to at least 80Hz. If you add multiple subs higher is usually even better in my experience. For reference (can't give exact figures because that Dirac Live current versions don't let you load a project unless you've connected it to the relevant processor) I'm currently using I think 120Hz or 125Hz between left/right 708i's and subwoofers. Center might be a bit lower, like 85-90Hz. The difference is because Dirac Live Bass Control was able to achieve better overall integration (per their predicted graphs) with the center crossed a little lower.

Now that I think about it, for just a little less $ per channel, I could have a sub on each of LCR for true full range, and maybe stick one or two at the back of the room for mode control. That'd take up a lot of space, though.

I think you could start simpler - get a second sub, place it where you can, raise the xover frequency to 100Hz or so, and then run Audyssey. Fix the target curve with the App - add the room gain back on the bottom end and get rid of the midrange notch. You may find you can stop there.

My local dealer who is handling the room remodel wants to put in Revel in-ceiling for the Atmos heights. Guess I could go with that and stick with the 705's.

Unless the Revels are meaningfully cheaper, JBL now has aimed, waveguide-loaded ceiling speakers in the Synthesis range that IMO would make more sense. That's what I would have used - the one with the 6.5" neo-magnet woofer and same compression driver as 70x - if I hadn't already had the TAD/Pioneer ceiling speakers on hand. With either Revel or Synthesis, I'd expect considerable installation savings compared to repurposing your 705P - you would only need to run speaker wire, rather than running line level and then having an electrician install outlets in the right places. One shouldn’t debase a room with exposed extension cords and wires everywhere when using this caliber of equipment.

 

[Tom C]

Don't worry - it's tedious but not that daunting. Audyssey does a credible job of integrating up to two subwoofers. See here: https://hometheaterhifi.com/reviews...rantz-av7702-surround-sound-processor-review/

Note this processor predated the iOS Audyssey app. You really need the iOS app to optimize use of Audyssey. The technology is good but the target curve is not.



That is too low for any installation I can conceive of. The only exception might be if the sub is one of those bad old 1990s units using a very long stroke motor with no inductance control. Those don't play high enough cleanly enough, so are best used just for that bottom octave. Actually best thrown away, but I digress.

Mains/subs crossover is better set by what works in the room, not the lower corner of the mains' FR. I would raise yours to at least 80Hz. If you add multiple subs higher is usually even better in my experience. For reference (can't give exact figures because that Dirac Live current versions don't let you load a project unless you've connected it to the relevant processor) I'm currently using I think 120Hz or 125Hz between left/right 708i's and subwoofers. Center might be a bit lower, like 85-90Hz. The difference is because Dirac Live Bass Control was able to achieve better overall integration (per their predicted graphs) with the center crossed a little lower.



I think you could start simpler - get a second sub, place it where you can, raise the xover frequency to 100Hz or so, and then run Audyssey. Fix the target curve with the App - add the room gain back on the bottom end and get rid of the midrange notch. You may find you can stop there.



Unless the Revels are meaningfully cheaper, JBL now has aimed, waveguide-loaded ceiling speakers in the Synthesis range that IMO would make more sense. That's what I would have used - the one with the 6.5" neo-magnet woofer and same compression driver as 70x - if I hadn't already had the TAD/Pioneer ceiling speakers on hand. With either Revel or Synthesis, I'd expect considerable installation savings compared to repurposing your 705P - you would only need to run speaker wire, rather than running line level and then having an electrician install outlets in the right places. One should debase a room with exposed extension cords and wires everywhere when using this caliber of equipment.

Thank you Mr. jhaider. I will try readjusting the crossovers tonight. And look into those JBL in ceiling speakers.
Is Dirac your preferred? Sounds like it is.

 

[jhaider]

Thank you Mr. jhaider. I will try readjusting the crossovers tonight. And look into those JBL in ceiling speakers.
Is Dirac your preferred? Sounds like it is.

I think all five room correction systems I tried in my previous system (Audyssey XT32, Anthem ARC 1M and Genesis, Dirac, and RoomPerfect) performed well after some manual tweaking. (Audyssey without the iOS app, no thanks.) Dirac Live Bass Control is a very good add on and IMO worth the $500 premium on products that support it. (A few pricey AVPs have DLBC built in.) In some respects it does more than a typical manual multisub calibration because it tries to optimize the blend between sub and each group of other speakers (mains, sides, etc.). Generally a manual calibration will focus on subs+LR or subs+LCR. It also has some big limitations (in my view) at present, such as being optimized for systems with identical capability subs, when often the most efficient layout will include bigger subs and smaller or limited-purpose subs.

Dirac has advertised a technology ("Unison") that would be perfect for high-capability mains such as JBL 708s. Basically it allows use of all the mains' bass capability in concert with subwoofers, for even more sources and thus in theory even more uniform bass. However, while Unison has been around in demos for years, there's no commercial home audio application yet. I think some cars (Polestar?) advertise tuning by Dirac Unison.

 

[changer]

I am still investigating the amount of DSP support to the speaker. Can you tell me Jay, why there is such a big difference between the single-wired and the biwire versions? The single wire uses two additional PEQs (2 and 6) and they are of big magnitude.

 

[jhaider]

I am still investigating the amount of DSP support to the speaker. Can you tell me Jay, why there is such a big difference between the single-wired and the biwire versions? The single wire uses two additional PEQs (2 and 6) and they are of big magnitude.

I don't recall if I've measured the biamp version. I suspect not, as I never personally intended to biamp based on comments attributed (admittedly hearsay to me) to @Charles Sprinkle regarding the lack of performance grounds to biamp these particular speakers. I'm not going to comment on someone else's data breach.

 

[Edgar]

I have the 708P in my mind since some time. But until now I didn't have the space and the funds. Now I have the space and the funds.
Before I buy these speakers I like to ask you: Did anything important happen since these speakers were released and this test? I.e. is there a newer better model? Or is a newer better model on the horizon and it would make sense to wait a little for xyz?
I look at this forum and check other audio information from time to time. But I don't do this all the time and I don't spend a lot of time on it. My idea is that I just want to have a couple of great speakers without spending a huge amount of time studying the newest developments.

 

[respice finem]

I have the 708P in my mind since some time. But until now I didn't have the space and the funds. Now I have the space and the funds.
Before I buy these speakers I like to ask you: Did anything important happen since these speakers were released and this test? I.e. is there a newer better model? Or is a newer better model on the horizon and it would make sense to wait a little for xyz?
I look at this forum and check other audio information from time to time. But I don't do this all the time and I don't spend a lot of time on it. My idea is that I just want to have a couple of great speakers without spending a huge amount of time studying the newest developments.

Depending on the "funds", there probably is - see today's review https://www.audiosciencereview.com/...s/genelec-8361a-review-powered-monitor.28039/

 

[Edgar]

Depending on the "funds", there probably is - see today's review https://www.audiosciencereview.com/...s/genelec-8361a-review-powered-monitor.28039/

Thanks, but no thanks. IMHO spending 4k on speakers is already a lot of money. 10k is definitely not the amount I am willing to spend.

 

[beefkabob]

You could piece together something cheaper and just as good, but it will take significant effort. You could piece something better together, but it will cost a lot more money. I'm on the hunt for a third one to get a C in LCR.

 

[Rahan]

The 7 series is still a very good deal. it is really cost efficient. Indeed you can save some bucks with the 705 and one good sub. But you won't fill a big room like the 708 does.

 

[beefkabob]

The 7 series is still a very good deal. it is really cost efficient. Indeed you can save some bucks with the 705 and one good sub. But you won't fill a big room like the 708 does.

705p will fill a room. They just require a higher crossover with the sub and won't get quite as loud. 705s are excellent up to about as loud as anybody should listen. 708p are excellent up to about as loud as anybody would want to listen, but they're not quite perfect as they get super loud. The next step up is a lot more money to be as loud as anybody could even stand to listen to for a short period of time.

 

[Buckster]

I was looking at the reviews on here of the 708 and the Stage A130 earlier (I currently own 305s and 308 MKIIs) as was looking for a bit more volume with lower distortion for my home cinema use.

Do the distortion measurements really show the Stage A130 providing lower overall distortion at volume (96dB) than the 708s ? considering the compression driver etc in the 708s this isn't what I would expect so I'm thinking maybe I'm not reading the graphs quite right

especially considering price of the A130s !

 

[Pio]

I was looking at the reviews on here of the 708 and the Stage A130 earlier (I currently own 305s and 308 MKIIs) as was looking for a bit more volume with lower distortion for my home cinema use.

Do the distortion measurements really show the Stage A130 providing lower overall distortion at volume (96dB) than the 708s ? considering the compression driver etc in the 708s this isn't what I would expect so I'm thinking maybe I'm not reading the graphs quite right

especially considering price of the A130s !

Check out this review of the Stage 120, hope this helps as the sound signature will probably be similar to the 130:

JBL Stage A120 Review

JBL Stage A120 Review

www.erinsaudiocorner.com

Keep in mind, the Stage A130 will need an amp as they're passive.

I have owned the 308's - currently own the 305Ps, 705Ps and the 708P. The 3 series (particularly the 308) measures better than what I have seen for the Stage series and the 7 series is a clear step above the 3 series in terms of dynamic output. I use the 708's at work and they're just amazing!

 

[jhaider]

Do the distortion measurements really show the Stage A130 providing lower overall distortion at volume (96dB) than the 708s ? considering the compression driver etc in the 708s this isn't what I would expect so I'm thinking maybe I'm not reading the graphs quite right

Without looking at the graphs (see next sentence for why), sure it's possible. THD does not correlate with listener perception until things get out of hand.

I'm not familiar with Stage A130 but I presume it has a lot less woofer than 708 (or 705, which per Sound und Recording's testing has higher bass SPL limits than 308) so it will not be able to reach the same output in the upper bass/lower midrange. IMO that's really the important area for a main speaker, given the typical spectral balance of music and human sensitivity to SPL by frequency.

 

[Richard Berg]

I was looking at the reviews on here of the 708 and the Stage A130 earlier (I currently own 305s and 308 MKIIs) as was looking for a bit more volume with lower distortion for my home cinema use.

Do the distortion measurements really show the Stage A130 providing lower overall distortion at volume (96dB) than the 708s ? considering the compression driver etc in the 708s this isn't what I would expect so I'm thinking maybe I'm not reading the graphs quite right

especially considering price of the A130s !

The Stage series is an amazing deal in a lot of ways, but I wouldn't turn to them for "more volume". Although harmonic distortion is very low, compression artifacts (which amounts to nonlinear distortion) creep in well before you get to ear-bleeding levels.

The purple line below is ugly -- if you're trying to push the speaker to this level, you'll be sad. I believe this comes from a single-tone sweep...right @hardisj ? If so, then a high-pass filter won't clean up the nonlinearities (though it'll improve overall power handling).

As @jhaider predicted, the woofer has trouble keeping up. 0.3dB probably isn't audible, but remember the "reference" response in the mid-bass is already quite depressed from the peaks above 1KHz, relying on either boundary gain or EQ to catch up.

Keep in mind the Stage series need a fair amount of EQ to sound as good as their active/DSP colleagues, which will further detract from power handling.

For something like an Atmos height channel, none of this matters For the side channels in a simple 5.x or 7.x, it might, depending how loud you play.

Deeper A120 talk should probably go here: https://www.audiosciencereview.com/.../jbl-stage-a120-review-by-erin-hardisj.27742/

 

[beefkabob]

I think something similar happens to the 708p at high db. The response linearity falls off a lot, but not at 102db. Probably more like 108 or 109db, which is pretty darned loud. Basically, the sound gets louder at some frequencies but not others as you approach the speaker's max.

 

[Pio]

JBL A130 test just published on Erins Audio Corner..

JBL Stage A130 Review

JBL Stage A130 Review

www.erinsaudiocorner.com

 

[RobL]

705p will fill a room. They just require a higher crossover with the sub and won't get quite as loud. 705s are excellent up to about as loud as anybody should listen. 708p are excellent up to about as loud as anybody would want to listen, but they're not quite perfect as they get super loud. The next step up is a lot more money to be as loud as anybody could even stand to listen to for a short period of time.

I have a pair of 705p’s and they are excellent nearfield, but at longer distances I find the sweet spot increasingly difficult to stay in. At 10’ slight head movement causes collapse of the image. Small waveguide maybe? Idk.