JBL 308P MKII Studio Monitor Review

[Tangband]

Sorry for my bad, it seems it’s playing at the level of accuracy as the 8030s at half the price ?

Not even near the performance of a Genelec 8030c. But for the money with som modifications, the Jbl 308 mkII is not bad.

 

[Tangband]

I don't see any info about that anyhwere.

JBL's website for 705P and 708P mentions DSP crossover, but not 305P/308P MKII

No, but there are a couple of videos with teardowns that shows it has dsp filtering.
Its cheaper and better

 

[tuga]

I once started a thread about Measuring the electronics inside active monitors.
An active speaker is but an all-in-one system and its performance is bound by the rule of the weakest link.

It is of course difficult to perform such measurements, and apparently some believe that because speakers produce more distortion everything upstream is inaudible anyway. Strange times. Or at least strange people.

 

[daftcombo]

What new dashboard?
Getting an updated 86/96dB distortion of them would be appreciated though.

The treble data is more precise now also IIRC

 

[technoian]

308P's stand-alone or 305P's combined with a subwoofer. Anyone have any opinions/experiences they care to share?

 

[Tangband]

I once started a thread about Measuring the electronics inside active monitors.
An active speaker is but an all-in-one system and its performance is bound by the rule of the weakest link.

It is of course difficult to perform such measurements, and apparently some believe that because speakers produce more distortion everything upstream is inaudible anyway. Strange times. Or at least strange people.

The Jbl 308 mkII is a budget monitor, maybe one of the best sounding for the money. But everything inside the loudspeaker is on a tight budget.
So, the performance is not close to good monitors costing three times as much.

 

[Music1969]

No, but there are a couple of videos with teardowns that shows it has dsp filtering.
Its cheaper and better

I agree DSP crossover is cheaper and can be better but still questioning if this 308P features A-to-D inside.

Still looking around the web for confirmation but can't find anything.

Different story with 708P of course.

 

[Zerohour]

JBL knows what they are doing. I got the Kalis fearing rear port of JBL might be an issue for my set-up.

I'm still eyeing the Kali for this very reason, a bit hard to find cheap monitors with front ports

 

[IVX]

Oooh, I remember the same looking JBL monitor, probably the older version yet, it had a lot of hiss noise. I measured that and found -87db(A), so need to love JBL too much to use it at a 1m distance The root cause was awful ST class D chip STA350, really low-end stuff with THD+N 0.5% -3db and noisy. I hope JBL jumped to Ti with the current monitor version.

 

[shal]

Oooh, I remember the same looking JBL monitor, probably the older version yet, it had a lot of hiss noise. I measured that and found -87db(A), so need to love JBL too much to use it at a 1m distance The root cause was awful ST class D chip STA350, really low-end stuff with THD+N 0.5% -3db and noisy. I hope JBL jumped to Ti with the current monitor version.

So, If I understand well, this JBL is not to use as near monitor because there is a lot of hiss
But also not as far monitor because the power is limited .

Very few use cases where this monitor is adapted for , no ?

 

[daftcombo]

308P's stand-alone or 305P's combined with a subwoofer. Anyone have any opinions/experiences they care to share?

Even with the 308p you might want a subwoofer.

See the review of the LSR 308 written by @NoAudiophile :

http://noaudiophile.com/JBL_LSR308/

In a last ditch attempt I used brute force to make the speakers better. I crossed the over to my subwoofers.
This is not what I wanted to do here. I wanted great speakers that would be as good as any other at making a broad range of sounds at a consistent volume with clarity. I wanted something to end the chase. Instead we are left with an expensive fix to an inherent problem on a damn good, but not perfect, speaker.

Crossover duty was performed by a minidsp, and the subwoofers were powered by my Behringer iNuke amp. (...)
With the low frequencies taken over by the subwoofers, the JBL's sound sublime.

 

[YSC]

Not even near the performance of a Genelec 8030c. But for the money with som modifications, the Jbl 308 mkII is not bad.

sorry for stupidity, but for the FR and in room response it lookse remakably similar to the 8030 except the 18k peak where 8030 have a dip??

 

[Tangband]

I agree DSP crossover is cheaper and can be better but still questioning if this 308P features A-to-D inside.

Still looking around the web for confirmation but can't find anything.

Different story with 708P of course.

This is a teardown of the 305 and 305mkII. Its essentially the same as for 308.
http://rdimitrov.twistedsanity.net/blog/show.php?entry=JBL LSR305 Teardown and Analysis
https://signalessence.com/whats-inside-the-jbl-305p-mkii-lame-teardown-quick-repair/

 

[Robbo99999]

So, If I understand well, this JBL is not to use as near monitor because there is a lot of hiss
But also not as far monitor because the power is limited .

Very few use cases where this monitor is adapted for , no ?

I have this speaker and I wouldn't want it sitting on my desk whilst I work on my computer, because of the hiss when no music playing on them. I have them at about 2m listening distance for TV/movie/music use and the hiss is a complete non-issue at that distance (can't hear it), but I wouldn't want them on my desk.

 

[daftcombo]

sorry for stupidity, but for the FR and in room response it lookse remakably similar to the 8030 except the 18k peak where 8030 have a dip??

Yes, true, and they dig deeper.
The real difference is the distortion.

 

[Tangband]

Yes, true, and they dig deeper.
The real difference is the distortion.

The sound is much better with Genelec 8030C.
I have compared both of them.

 

[YSC]

Yes, true, and they dig deeper.
The real difference is the distortion.

IC!! being lazy and bad memory on graphs I didn't check the distortion and only look at the FR! it looks like good manufacturers manage to make good studio monitors relative cheap with very good FR like the Adam T and this, but for perfection with distortion then price just goes up like the genelec?

 

[andreasmaaan]

I think its mostly depending on :

1. Lack of damping material inside the loudspeaker. The box is almost empty, making standing waves inside the loudspeaker to appear: - distortion. It should be about 3 or 4 times more of the damping material.
2. Lack of crossbracing inside the loudspeaker. The walls are vibrating like crazy: - distortion. Cured with a cross bracing L - to R wall.

Most of the energy in these standing waves and wall vibrations will be at excitation frequencies, with relatively little energy (in relation to the output of the drivers, in any case) at harmonics of these - or so I would have thought...

I.e. I doubt these phenomena would contribute significantly to harmonic distortion. I imagine what we're seeing here is primarily driver distortion.

 

[LearningToSmile]

Very happy to finally have measurements of the 308P MKII - I own one and my subjective impressions were very good, but I noticed a lot of people on this forum and elsewhere were quick to dismiss them based on the some weird assumptions. I've seen people saying that the LSR308 was good but 308p were ruined, I've seen people saying that it must've obviously be worse than the 305P because... I don't exactly know why but they were sure of it(something about the company designing only the 305 to be a complete package and only scaling up the larger version, which seemed like a really silly assumption to me).

For the hiss and general usage - I couldn't use them on desk but not just because of hiss, but more because they're so big it almost felt like the sound wasn't coming together properly this close(plus desk reflections interferred with the bass). I currently have them set-up on stands behind my desk, with the faces of the speakers being around 1.5 meters from my head when sitting at the desk. This is a perfect listening distance. In a quiet room I could hear the hiss but in my home office my PC fans are louder than any hiss coming from the speakers. I do have to note that when I used them unbalanced the hiss seems to be worse with my setup, so I'd definitely recommend using a balanced source. But I have some grounding issues so it might be no difference for others.

Even with the 308p you might want a subwoofer.

See the review of the LSR 308 written by @NoAudiophile :

http://noaudiophile.com/JBL_LSR308/

Also agree with that - while they are good performers in the bass region, once I added a subwoofer they leveled up.

Overall, even without taking the frequent sales into account, they're an outstanding value.

 

[Robbo99999]

@amirm , or @MZKM or others - for EQ purposes is it OK for me to use the data in the CEA2034 file, because I notice it is at the higher 110dB level rather than the 85-90dB range seen in the graphs in the review. Do I need to apply a correction to the data, or can I just base my EQ on the data in the CEA2034 file which is at the higher 110dB level? (I'm thinking I can just use it at the current 110dB level, but wanted to be sure).