JBL 308P MKII Studio Monitor Review

[Ellebob]

Without hiss, Kali. 308 and LP8 pretty close in sound signature when doing blind testing with people. LP6 seems a efinite upgrade over 305/306. We carry both where I work and I take them home and do comparisons with family and friends. They are not double blind but participants rarely know which speaker is playing.

What is the budget? Further up the price range you might find class AB amps instead of class D. But, even higher end monitors like Genelec use class D in many of their monitors.

 

[Joeyd33]

Without hiss, Kali. 308 and LP8 pretty close in sound signature when doing blind testing with people. LP6 seems a efinite upgrade over 305/306. We carry both where I work and I take them home and do comparisons with family and friends. They are not double blind but participants rarely know which speaker is playing.

What is the budget? Further up the price range you might find class AB amps instead of class D. But, even higher end monitors like Genelec use class D in many of their monitors.

Budget could be anywhere from 400-800, give or take a bit. Did you by any chance listen to the IN-8 V2’s? If you did are they worth the extra over the LP’s?

I’m not sure exactly what to call it but the JBL’s not only had a nice dynamic sound but it seemed to present sound in such a different way. If I have to be honest the only way I can describe it as a drug like effect similar to weed or psychedelics.

I’m also open to other speakers, they do not have to be monitors or powered. I just really hate the hiss/noise floor of what the JBL’s had. I am very sensitive to certain sounds and sadly the JBL’s noise really bothered me.

 

[Ellebob]

I have had the IN8 and IN5 V2s. We didn't carry Kali when any of the V1 models were out except the WS12 sub we had the V1. The IN series is a definite step up from the LP series. Particularly in the mid range. I have the IN5 in my home now and it is staying, unless you play loud I wouldn't spend the extra for the IN8. Although, not a huge price difference.

Also, we compared the IN5 to the Kef R3 (not meta) and I liked the IN5 better.

We also did a comparison for a customer between the R3 and R3 Meta and that was VERY close. The client bought the Meta but if I owned the R3 no way would I upgrade. More of a lateral move, IMHO.

 

[Joeyd33]

I have had the IN8 and IN5 V2s. We didn't carry Kali when any of the V1 models were out except the WS12 sub we had the V1. The IN series is a definite step up from the LP series. Particularly in the mid range. I have the IN5 in my home now and it is staying, unless you play loud I wouldn't spend the extra for the IN8. Although, not a huge price difference.

Also, we compared the IN5 to the Kef R3 (not meta) and I liked the IN5 better.

We also did a comparison for a customer between the R3 and R3 Meta and that was VERY close. The client bought the Meta but if I owned the R3 no way would I upgrade. More of a lateral move, IMHO.

Yeah seems I might like the IN series more.

I should have mentioned that I do also want to try and figure out if these are ok for movies,especially the IN series and that‘s why I was looking at the 8 inch versions of the speakers. For whatever reason I found the JBL’s to sound a bit muted in the vocals during movies.

 

[JackStorm]

How do they sound compared to 306P MKII, Kali LP-6v2 and ADAM T7V. Some people mentioned before that LP-6v2 don't sound as good even though they technically measure better and some people mentioned that 308P sounds like it has far more "distortion" and "sounds bloated" even when comparing to 305P like in this video, but it might be his untreated room. So my question to people that owned or listened to some of these models is do 308P sound really better than other models mentioned and would they have less "distortion" if paired with a subwoofer.

 

[staticV3]

do 308P sound really better than other models mentioned and would they have less "distortion" if paired with a subwoofer.

Pairing a subwoofer with your monitors can only reduce their distortion if the sub and monitors are well integrated with a proper crossover, which applies a high-pass filter to the monitors and a matching low-pass filter to the sub.

It's also possible to skip the high-pass filter, let the monitors play as-is, and only adjust the sub's LPF to match the monitors' natural roll-off.

If done well, that can result in a smooth in-room response with extended low frequency extension, but without the advantage of reducing bass distortion in the monitors.

 

[gino1961]

Pairing a subwoofer with your monitors can only reduce their distortion if the sub and monitors are well integrated with a proper crossover, which applies a high-pass filter to the monitors and a matching low-pass filter to the sub.
It's also possible to skip the high-pass filter, let the monitors play as-is, and only adjust the sub's LPF to match the monitors' natural roll-off.
If done well, that can result in a smooth in-room response with extended low frequency extension, but without the advantage of reducing bass distortion in the monitors.

Hi completely agree on the 1st solution that is my optimum approach for a full range speaker
I did some experiments in the past with an electronic crossover on a small 2 ways
Cutting out all freqs below 150Hz i was getting no bass clearly but the mid highs were much much better Expecially the midrange
When a small woofer has to playback a heavy bass line and the midrange at the same time there is what they called IMD
It can be shown with a multitones test quite easily there will be many peaks not present in the test signal
Some powered subs have a internal xover and an output for powered satellites
The results can be spectacular even with cheap satellites
Instead subs must be very good Like the fundations in a house

 

[Sal1950]

Cutting out all freqs below 150Hz i was getting no bass clearly but the mid highs were much much better Expecially the midrange

I highly recommend rolling off most 2-ways around 80hz.

 

[Robbo99999]

I highly recommend rolling off most 2-ways around 80hz.

I was surprised to find that with my JBL 308p's that 120Hz crossover sounded better than 90Hz crossover, and I confirmed through measurements that frequency response was the same. I wasn't expecting that.

 

[trl]

I was surprised to find that with my JBL 308p's that 120Hz crossover sounded better than 90Hz crossover, and I confirmed through measurements that frequency response was the same. I wasn't expecting that.

It mostly depends on the subs you're pairing them with, which in your case are what model?

 

[Ellebob]

By changing the crossover you probably solved some room mode problems or a boundary issue. Crossovers should be set by room acoustics and not speaker capability unless the speaker is not capable, like a small speaker which would require a higher crossover. Your results are not surprising.

 

[gino1961]

I highly recommend rolling off most 2-ways around 80hz.

the optimum cut depends clearly on the woofer With smaller and also cheap woofer the distortion undergoes a sharp surge even belove 120Hz
a 8" midwoofer could be mandatory to cross at 80Hz And a 8" unit will start to have issues above 1kHz
it can be seen on the very valuable distortion tests in this excellent site
if the goal is high SPLs and low distortion i would not use a driver below its fsx2

 

[gino1961]

I was surprised to find that with my JBL 308p's that 120Hz crossover sounded better than 90Hz crossover, and I confirmed through measurements that frequency response was the same. I wasn't expecting that.

you forget distortion For sure the woofer in the 308 works better if you take out the more challenging frequencies
The interesting thing is that if used well (i.e. inside their best range) even cheap drivers can sound very good indeed A friend of mine has got very good sound from a cheap car unit
Low noise low distortion should be the goals

P.S. i have just checked the distortion graphs in the lab review I am puzzled I would investigate the woofer quality

 

[Robbo99999]

It mostly depends on the subs you're pairing them with, which in your case are what model?

SVS SB1000 Pro is the sub I'm using. (So I don't know if that stacks up with what you would expect?)

By changing the crossover you probably solved some room mode problems or a boundary issue. Crossovers should be set by room acoustics and not speaker capability unless the speaker is not capable, like a small speaker which would require a higher crossover. Your results are not surprising.

Well, the measured frequency response at listening position was effectively the same for both tests when I compared 90Hz vs 120Hz crossover, which you can see in the following pic. If I remember rightly I had already setup the EQ settings for 90Hz & 120Hz crossover through multiple windowed measurements at listening position and then in the following graph I just left the mic at one position to make a comparison. So frequency response was effectively taken out of the equation when I was listening to 90Hz vs 120Hz crossover - to see which one sounded best to me. So I'm thinking the difference is IMD related. To note the 120Hz crossover is with the ports stuffed with socks and the 90Hz crossover is port open on the JBL 308p speakers. (120Hz crossover is the blue line).

you forget distortion For sure the woofer in the 308 works better if you take out the more challenging frequencies
The interesting thing is that if used well (i.e. inside their best range) even cheap drivers can sound very good indeed A friend of mine has got very good sound from a cheap car unit
Low noise low distortion should be the goals

P.S. i have just checked the distortion graphs in the lab review I am puzzled I would investigate the woofer quality

My explanation for why I preferred the 120Hz crossover is IMD related (which is what you're saying).

 

[gino1961]

SVS SB1000 Pro is the sub I'm using. (So I don't know if that stacks up with what you would expect?)

Well, the measured frequency response at listening position was effectively the same for both tests when I compared 90Hz vs 120Hz crossover, which you can see in the following pic. If I remember rightly I had already setup the EQ settings for 90Hz & 120Hz crossover through multiple windowed measurements at listening position and then in the following graph I just left the mic at one position to make a comparison. So frequency response was effectively taken out of the equation when I was listening to 90Hz vs 120Hz crossover - to see which one sounded best to me. So I'm thinking the difference is IMD related. To note the 120Hz crossover is with the ports stuffed with socks and the 90Hz crossover is port open on the JBL 308p speakers. (120Hz crossover is the blue line).
View attachment 362458


My explanation for why I preferred the 120Hz crossover is IMD related (which is what you're saying).

Hi thanks and perfect i have seen now my bad
still looking at the review i see very high distortion anyway Maybe i am exagerating the problem If it sounds good must be good
no more question i promise

 

[Robbo99999]

Hi thanks and perfect i have seen now my bad
still looking at the review i see very high distortion anyway Maybe i am exagerating the problem If it sounds good must be good
no more question i promise

Naa, it's ok, you haven't done anything wrong!

 

[trl]

the measured frequency response at listening position was effectively the same for both tests when I compared 90Hz vs 120Hz crossover

I get it, good thing I guess, although I would still vote for a sub crossover @ 90 Hz in such case, given that 120 Hz is easier to locate in the room than the 90 Hz, but YMMV.

 

[Robbo99999]

I get it, good thing I guess, although I would still vote for a sub crossover @ 90 Hz in such case, given that 120 Hz is easier to locate in the room than the 90 Hz, but YMMV.

Fair enough, although I don't get sub localisation issues, the sub is somewhere inbetween the speakers in relation to the listening positions.