JBL 708P Review (Professional Monitor)

[Frank Dernie]

I have done some casual sound level measurements, on many genre of music, and found even 90db to be quite loud.

The highest peaks I've measure even on several classical pieces, were honestly somewhat unbearable to my sense of hearing at even around 100-105 db.

And yes the average level was in the 80s.
It was not due to equipment overload, but more my ears just get that feeling that is sounds "too loud".

I have done measurements at concerts. It isn't feasible/too embarrassing to measure continuously but at a Mahler concert of a piece I know well I measured the peaks, quiet bits and general orchestral playing.
The peak was ~125dB - I was in about the 5th row of the concert hall. The general level was 80-85dB.
I don't have commercial recordings with that much dynamics recorded, there probably are none. I do have uncompressed recordings I made myself at a music festival with a pair of microphones balanced by position rather than electronics.
They are the most realistic recordings I have. I do have some commercial recordings which are quite dynamic, but not the full monty.

IMO the reason a HiFi sounds too loud is more to do with speakers and maybe electronics being incapable that it actually being loud.
If I compare the same music on LS50, my big 3-way Goldmunds and my horns the 2-ways sound loud before they measure loud, the 3-ways are pretty good on everything but the loudest peaks and the horns, whilst being a bit more coloured than the big 3-ways, get the peak level without sounding too obviously "loud".
They are 109dB/watt though.
Generally a reasonably sized domestic HiFi is completely incapable of getting anywhere near orchestral concert levels without sounding "loud" IME.

 

[respice finem]

...Generally a reasonably sized domestic HiFi is completely incapable of getting anywhere near orchestral concert levels without sounding "loud" IME.

And even for those few that would be capable of it "as themselves", the effect will be spoiled by the listening room "qualities". One of the reasons why I prefer headphones for classical music.

 

[Frank Dernie]

And even for those few that would be capable of it "as themselves", the effect will be spoiled by the listening room "qualities". One of the reasons why I prefer headphones for classical music.

Interesting, I don't find this and I only listen to headphones rarely, mainly travelling before I retired, I have never found them to be preferable on any sort of music, goodness knows why I buy them!.

 

[Pio]

this review inspired me to bring my 708's from the station home... man they're awesome!!!!

 

[Tovarich007]

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.

You get 113 Db with deep bass at your 3.5 m listening distance !! And you consider they don't go loud and deep enough ?? Well, 113 Db (with deep bass moreover) is extremely loud ( mind your audition ! ) and that's impressive performance for a not so large speaker.

 

[q3cpma]

Could these very regular resonances at 1.5-4 kHz be the famed "horn sound"?

 

[Kain]

Since we are talking about SPL, would you guys say the 708i/708P (crossed over with subwoofers at 80 Hz or higher) will be able to provide "all the SPL that you might need" in a small room (for movies and music) where the listening distance is around 7 ft? Room size is about 12 ft long x 11 ft wide x 9.5 ft high. Note that this is for someone who listens really loud.

 

[infinitesymphony]

And even for those few that would be capable of it "as themselves", the effect will be spoiled by the listening room "qualities". One of the reasons why I prefer headphones for classical music.

The idea of a room adding its own qualities reminds me of the original technique of cramming ensembles and singers into a tiny room around a phonograph to generate a relatively dead-sounding recording. Then when you played it back on the Gramophone in your large hard-surfaced Victorian parlor, you generated your own unique custom reverb. It can sound eerily realistic depending on the content.

Edward Elgar, 1914

 

[q3cpma]

Since we are talking about SPL, would you guys say the 708i/708P (crossed over with subwoofers at 80 Hz or higher) will be able to provide "all the SPL that you might need" in a small room (for movies and music) where the listening distance is around 7 ft? Room size is about 12 ft long x 11 ft wide x 9.5 ft high. Note that this is for someone who listens really loud.

Probably, but distorsion really isn't that good, one can only guess with IMD. If you listen very loud at 7 ft, a 3-way should be mandatory.

Room is small, so I doubt you'll reach such limitations, though.

 

[BDWoody]

Since we are talking about SPL, would you guys say the 708i/708P (crossed over with subwoofers at 80 Hz or higher) will be able to provide "all the SPL that you might need" in a small room (for movies and music) where the listening distance is around 7 ft? Room size is about 12 ft long x 11 ft wide x 9.5 ft high. Note that this is for someone who listens really loud.

I'm in a 14x20x9 room, listening position is about 13'. I tend to listen at a level others consider loud...80+dB.

I will frequently have it at reference levels (for music), and it handles everything very well.

The LS50's I have are good for maybe 5'.

I also have these as my front 3 speakers for movies, and usually the 0dB mark is crazy loud... Course, that's with 3 of these and 6x705P's (same amplification) plus a few subs. Point is, I haven't felt like they are lacking in power at this distance. I can't imagine you'd need more for your 7'.

 

[ROOSKIE]

There was virtually no distortion, but more like "Ear overload" in a regular/small sized room.

My listening room is 13X20 but loud just takes over in a smallish sized room. I've heard equally loud in far bigger rooms, but it is less strained and you can move away from it more, and the walls are further back, so you feel more at ease.

Psychoacoustics at work.
Likely not an uncommon sense of perception though certainly not universal and will depend IMHO on how live the room is.
Really our own perception of the space the playback is taking place in really will affect the sound for each of us in some different ways.
Of course, you would have to measure both SPL and HD/distortion to be sure you comparison is apples to apples as well.

Since we are talking about SPL, would you guys say the 708i/708P (crossed over with subwoofers at 80 Hz or higher) will be able to provide "all the SPL that you might need" in a small room (for movies and music) where the listening distance is around 7 ft? Room size is about 12 ft long x 11 ft wide x 9.5 ft high. Note that this is for someone who listens really loud.

Yes, without a doubt . That is a very small room.
Based on my expereinces with even less capable speakers I say do not hesitate.
You will actually have more trouble controling room modes than anything else.

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.

While your points are generally excellent and I deff want folks to use a subwoofer along with monitor style speakers, I do think 83db average SPL in a medium room is no issue at all for a pair of many good monitors/bookshelves.
These 708p's in particular look well suited to play much louder than that without strain in a room. The 96db Distortion characteristics are still better than most 6" woofers at 86 and I suspect a measurement of them at 106db would actually be very usable. (read - still very HIFI)
So for a pair, high passed to sub(s), with room gain added in and you are looking at some very loud clean playback at a 10ft distance in a medium to medium largish room. Have a large, big or huge room then yah get some huge speakers.

In fact get these (and some subs)

 

[respice finem]

Interesting, I don't find this and I only listen to headphones rarely, mainly travelling before I retired, I have never found them to be preferable on any sort of music, goodness knows why I buy them!.

Yes this is interesting, there really seem to be two groups, one will prefer speakers, the other one headphones. I'm leaning to the latter, maybe because i'm using headphones since early childhood (different early conditioning of hearing?). An exception is (so far) surround sound.

 

[ROOSKIE]

Probably, but distorsion really isn't that good, one can only guess with IMD. If you listen very loud at 7 ft, a 3-way should be mandatory.

If you add a sub(or two) at 80hrz and high pass the monitor, you now have a pretty capable 3-way don't you?
Not to mention, that room is tiny by the way.

What I am really interested in why you are so discouraged about the Harmonic distortion levels? What is that you are looking for and why? So many folks pilling on this on this thread on the HD. Doesn't seem to correlate with my experiences, nor anything I have ever read that is suitable to quote here. So what gives?

IMD can not be inferred, it is a different measurement with a multitude of factors that would affect it.
One easy example of 1 factor.
Driver A&B are the same size.
Driver A has the same HD at 96db as driver B
Driver A has a 1mm Xmax, Driver B has 44mm Xmax.

 

[respice finem]

The idea of a room adding its own qualities reminds me of the original technique of cramming ensembles and singers into a tiny room around a phonograph to generate a relatively dead-sounding recording. Then when you played it back on the Gramophone in your large hard-surfaced Victorian parlor, you generated your own unique custom reverb. It can sound eerily realistic depending on the content.

Edward Elgar, 1914

There is hardly anything that hasn't been tried in acoustics and sound recording in general. In this example, probably one of the factors might have been to deliver enough SPL for all instruments to get properly recorded at all. The sensitivity of the "equipment" those days was quite, excusez le mot, "deplorable"

 

[Pearljam5000]

Does the 708P gets much louder than Genelec 8050b?
How do they compare in general?

 

[BDWoody]

Does the 708P gets much louder than Genelec 8050b?
How do they compare in general?

@Spocko sent one in for the treatment, so hopefully we'll know soon.

@Amir , do you still have the 708P? Any chance of a head to head? It looks like these could both be on anyone's short list...your direct comparison would be interesting.

 

[Pio]

Does the 708P gets much louder than Genelec 8050b?
How do they compare in general?

The JBLs have a variation of the D2 compression driver found in the flagship M2 vs the Genys metal dome - so the 708s get very loud and most importantly, w/o dynamic compression. I also own a pair of older Genys, (1031A) after a certain volume, they just start to hold back. The 708s are just spectacular.

 

[Frank Dernie]

Yes this is interesting, there really seem to be two groups, one will prefer speakers, the other one headphones. I'm leaning to the latter, maybe because i'm using headphones since early childhood (different early conditioning of hearing?). An exception is (so far) surround sound.

I bought my first headphones in 1970 when I was 20. Koss electrostatics. I was disappointed and despite trying lots since I have never found them compelling. I have 7 or 8 pairs of different quality/connection the most used are blutooth with phone when travelling since I usually listen on speakers at home, even when I start on 'phones.
The only chance I had to listen to music as a child was my mother's "radiogram" and tapes I made myself on my mono valve tape recorder. I had no concept of high fidelity sound then.

 

[Frank Dernie]

Just measured the sound levels through a recording I enjoy. average 80.2 max 98.8, min 32.3.
The peaks are certainly limited at the mastering stage but not too noticeably.
FWIW.
Edit, C-weighted at 17 feet from the speakers

 

[richard12511]

You get 113 Db with deep bass at your 3.5 m listening distance !! And you consider they don't go loud and deep enough ?? Well, 113 Db (with deep bass moreover) is extremely loud ( mind your audition ! ) and that's impressive performance for a not so large speaker.

That 113dB measurement was with the RS2(subwoofers) handling the bass, though I don't remember if they were crossed at 100Hz or 80Hz at the time, as I've recently switched from 100Hz to 80Hz. I've actually never seen the red clip lights on the 8351s when they're crossed to subs.