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JBL 308P MKII Studio Monitor Review

andreasmaaan

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Ok, so the measurements are great and the hiss, is just the hiss. But I tried these at my desk and, they did not work out.

I am not a "soundstage guy" but holy hell these sounded congested and "wrong" on my desk. The imaging was off no matter what I did. I even hammered out the frequency response with Dirac 1.0 back to flat (ish) and still sounded wrong.

I only wired them in since my LXmini rig is so complicated the 3-way crossover broke after a botched software update. I absolutely love the LXmini over this, but thats a $700 DIY kit (not including DSP and amplification).

I am back to loving the 308 in my dining room. They need space I think. Distance from the listener.

Also, it’s hard to make any conventional speaker sound good standing on a desktop/table. How have you got the LXmini setup?
 

ruinevil

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Help me to understand why I hear so much of this with many powered speakers? I can stick my ear completely into the waveguide of my 3600s and not hear a bit of hiss from my 25 yo Adcoms. Why can't they design these cheap plate amps to be quiet?

http://rdimitrov.twistedsanity.net/blog/show.php?entry=JBL LSR305 Teardown and Analysis

Basically you are hearing power supply noise in the ADC/DAC system. Part of the reason is that they use a single slab of PCB for both the power supply and ADC/DAC system. I think JBL purposely does this to keep it from cannibalizing their higher end monitors.
 

LearningToSmile

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Ok, so the measurements are great and the hiss, is just the hiss. But I tried these at my desk and, they did not work out.

I am not a "soundstage guy" but holy hell these sounded congested and "wrong" on my desk. The imaging was off no matter what I did. I even hammered out the frequency response with Dirac 1.0 back to flat (ish) and still sounded wrong.

I only wired them in since my LXmini rig is so complicated the 3-way crossover broke after a botched software update. I absolutely love the LXmini over this, but thats a $700 DIY kit (not including DSP and amplification).

I am back to loving the 308 in my dining room. They need space I think. Distance from the listener.
Yeah, way too close - if you put them on stands right next to those subwoofers in the back that probably would be around the same distance I had to put mine at to sound good. They need the space. The good thing is that despite the rear port they can be pretty close to the wall with no issues in my experience.
 

Xyrium

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Moral of my story, I should have listened to my ears. When I first got this speaker, I thought it sounded amazing. I compared it to my Revels and JTRs in my main room and thought it sounded as good as those speakers did. I took it into my office and thought it sounded wonderful in there, too. I even tested all the treble settings and found that I preferred the default(+0) treble setting. Then...I measured the response in my office, and it was tilted upwards(not downwards like I expected). After that, I started thinking it was too bright, so I flipped the -2 treble switch on the back, but the placebo was too much, and I ended up relegating them to storage. In some sense I'm happy, as it led me to the Genelec 8030c for my office, but my initial impression was correct, these are great speakers :facepalm:

Second moral of my story, don't trust in room measurements.

The hobby is definitely a trying one!

What I'm confused about, is Amir's seeming preference (not a criticism, everyone has a preference!) for relatively higher distortion speakers. He loved the Revels, and both of them drive distortion levels above preference, just below 500 Hz. Now, he loves this one, and the distortion is fairly terrible across the entire audio spectrum. This leads me to believe that some folks really do enjoy the sound of distortion, that ratio where the main signal is swamped by other frequencies not in the original recording.

However, if critically listening to a speaker that is reproducing a recording of acoustic instruments, a quartet perhaps, whereas the distinct timbre of instruments can be realized, would that preference still hold? I would imagine that would not be the case, as I'm certain you would mask many of the instruments' qualities in THD.

Finally, how does THD impact imaging? I would imagine that it would blur the soundstage a bit, compared to a well designed, low distortion piece of equipment.
 

LeftCoastTim

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Agreed. This review really has me wondering what went wrong with the 305p.

I have pondered on this for some time. My guess to the answer is that Yamaha HS5 is "The Reference Standard" for 5" monitors at this price range for many, and a neutral monitor will sound very dull in comparison to it. And instead of losing a sale with a better product, JBL just changed the EQ setting in the DSP to match the HS5.
 

JohnBooty

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If you want to get a taste of accurate sound production that manages to delight, the JBL 308P MKii is a wonderful entry into this world. You would quickly learn that what research says about preference and accuracy being two sides of the same kind is very much true.

Amen!!! With this glowing praise, I might expect a "golfing" panther, but like you say... no reason to obsess over the panther ratings.

As with many powered speakers, amplification for the woofer is the limiting factor. This speaker with 100 watts or more to power the woofer would be so darn perfect. As it is, it will get quite loud and present ton of bass. Just don't expect miracles in overall loudness.

Yeah. These JBLs make for easy subwoofer integration with a nice low crossover point. I have the 306P crossed over to my subs at around 55hz or 60hz; I forget exactly. I'm sure the 308P could be crossed over a bit lower.

JBL's "matching" 310S sub is quite nice and has a built-in crossover. However the high-pass is set at a non-configurable 80hz, and it "only" plays down to around 30hz. So, more of a match for the 305P than the 306P/308P.
 
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FrantzM

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I cross my 3 LSR 308 at 80 Hz and have no regrets... Yeterday had a blast, litterally with "V for Vendetta".. Clean peaks of 107 dB at Listening position ... I had to quickly reduce it as that level is unbearably loud for me, even peaks of 100 dB were loud for me ... I kept on smiling knowing that my total outlay for speakers ( 3 LSR 308, 2 LSR 205, 2 Bose 161) and subwoofers (3 Parts Express Sub 1500) is less than $2000 ...
IMO the LSR 308 could well be the greatest bargain in Audio. (I am an audiophile, hyperboles galore, Sue me :)) ...
 

BYRTT

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Great thanks to Amir :) the acoustic review..

Some asked about 308P MKII verse T8V, >100Hz side by side animation..
308P_verse_T8V_100Hz-20kHz_x2x1_1200mS.gif



308P MKII verse T8V, overlaid animation 20Hz-20kHz..
308P_verse_T8V_overlaid_x1x1x1x1x1x1_800mS.gif



308P MKII verse T8V, >300Hz listening window directivity pattern..
308P_verse_T8V_4_EDIT_2.png
 
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Chromatischism

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Background noise will be pretty high I am afraid but I can experiment and see.
I have the Mackie MR624's on the desk here and I never hear any hiss.

To test the effect of background noise, if I turn off my nearby WINIX air cleaner and my PC fans, I can just start to detect a hiss from about 2 feet if I get my ear perpendicular to the speaker. But leaning back in my chair, it's gone again.

At any rate, it's a very benign sound.
 
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amirm

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Question:

This is 86 and 96 dB measured at the mic, right? So at our seat, quite a bit lower?
Distortion measurements are at equiv. of 1 meter/3.3 feet. In reality they are performed at 1/3 of a meter but then compensated to represent 1 meter.
 
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amirm

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What I'm confused about, is Amir's seeming preference (not a criticism, everyone has a preference!) for relatively higher distortion speakers.
I don't have a preference for distortion. Indeed I clearly noted in the review that distortion sets in as you turn the volume up. The 86 dBSPL is quite loud so it is well into distortion range but when listening one can obviously listen at much lower level since these are used near-field. So in general you can't compare the distortion figures for near-field use against far field.
 

Jinjuku

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listen at much lower level since these are used near-field. So in general you can't compare the distortion figures for near-field use against far field.

Not sure why readers are missing this obvious point. They are not meant to peel the carpeting off the floor. I use these for Vocal and Jazz. My Statements are rock and large orchestral.
 

Chromatischism

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What I'm confused about, is Amir's seeming preference (not a criticism, everyone has a preference!) for relatively higher distortion speakers. He loved the Revels, and both of them drive distortion levels above preference, just below 500 Hz. Now, he loves this one, and the distortion is fairly terrible across the entire audio spectrum. This leads me to believe that some folks really do enjoy the sound of distortion, that ratio where the main signal is swamped by other frequencies not in the original recording.
It may be a correlation but not a causation. One example is the Buchardt S400 which measures very well, especially with a slight toe-in, yet he did not prefer it. Another may be the Infinity IL10. At any rate yes, at desk listening levels these distortions are not rising much yet.
 

Sprint

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I cross my 3 LSR 308 at 80 Hz and have no regrets... Yeterday had a blast, litterally with "V for Vendetta".. Clean peaks of 107 dB at Listening position ... I had to quickly reduce it as that level is unbearably loud for me, even peaks of 100 dB were loud for me ... I kept on smiling knowing that my total outlay for speakers ( 3 LSR 308, 2 LSR 205, 2 Bose 161) and subwoofers (3 Parts Express Sub 1500) is less than $2000 ...
IMO the LSR 308 could well be the greatest bargain in Audio. (I am an audiophile, hyperboles galore, Sue me :)) ...

Great. I tested 305 in my living room (listening distance 3,5 meters) against M-Audio and JBL really outshines. What is your listening distance from your 3 LSR 308?
 

Robbo99999

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Distortion measurements are at equiv. of 1 meter/3.3 feet. In reality they are performed at 1/3 of a meter but then compensated to represent 1 meter.
Messy post, made some mistakes in my testing & re-edited my post, crossed out stuff that is wrong so you don't have to read it!

Ah, so if you listen at a further distance (like I do) of about 2m, then distortion could become more of a practical problem as you have to turn up the signal. I thought I'd try to work out just now how many dB's my JBL 308p Mkii's would put out during my loudest listening, so I left the volume knob on the back of the speakers at 4.5 and put my E30 DAC to 0dB with -2dB in windows volume for intersample overs, and ran a REW frequency sweep configured at 0dB in REW software, and measured at my 2m listening position and this is what I got: Ignore this first graph, made a config error in REW.
JBL 308 distortion.jpg

On average I guess that's 73dB at a 2m listening position with maximums of 80dB (this is including a little bit of RoomEQ too, as well as Anechoic EQ). I'm not sure how valid the distortion measurement is, but I think I remember hearing somewhere that is was important that distortion was below the Noise Floor.....I highlighted Noise Floor in the pic there and it looks like distortion is below that curve for the most part.

How valid is this and what kind of 1m equivalent dB would my speakers be outputting given this measurement was done at 2m? I'm just trying to get a perspective on where my maximum listening level is in relation to the listening level you used in your distortion test - thereby I can judge if I'm getting more or less distortion during my listening than what was presented in your review?

EDIT: just realised something, you were measuring 1 speaker and I'm measuring 2 speakers in my graph there. So would I subtract 6dB from my graph to normalise the influence of me having 2 speakers vs your 1 speaker? If that's the case then each of my speakers is operating at an average of 67dB and a peak of 74dB. In terms of translating your 1m dB measurement to my 2m listening position I found this online calculator (http://www.sengpielaudio.com/calculator-distance.htm), and if I put in your 86dB at 1m distance I get 80dB at my 2m listening position. Given all of the above that I have written in this "EDIT" then my max listening volume per speaker is 19dB on average lower than your 86dB distortion test and at the maximum peaks in the frequency response it is 12dB lower than your 86dB distortion test. I'm not sure if I've made the correct premises here though. I guess this means that distortion is likely a lot lower at my listening levels than your test, even at my 2m listening position. If peoples know if my assumptions are valid or not then would be good to hear, I'm not 100% sure.

EDIT #2: just realised my previous graph was wrong somehow as the SPL was too low so I re-ran it and got a higher SPL, not sure what I did wrong in the REW setup before, I think I must have not set dBFS for the sweep to 0 dBFS properly. Will attach the proper graph following:
JBL 308 distortion#2.jpg

So there are a few times where the 2nd Harmonic is above the noise floor, at 40Hz and at 200Hz, but again I don't know how valid this kind of test is in determining true distortion. Will redo my calculations from my first edit now......following is the thought calculation process:
  • At 2m listening position average SPL of 81dB, max peaks of 90dB.
  • This equates to 75dB average SPL and 84dB for max peaks per speaker if you subtract 6dB for the fact I'm measuring 2 speakers rather than Amir measuring one.
  • We can add back 6dB though to normalise it to Amir's 1m distance distortion measurement because I'm at 2m listening position, so back at 81dB average SPL and max peaks of 90dB per speaker at hypothetical 1m measuring distance. Conclusion: The 86dB Amir distortion measurement is really quite applicable/equatable to my max listening volume. In reality most of the time I'm running around -6dB on my E30 DAC Preamp though, but I do turn it up to 0dB sometimes which is applicable to Amir's 86dB distortion measurment.
Not sure how valid this all is, but it's my best interpretation, ha!
 
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richard12511

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The hobby is definitely a trying one!

What I'm confused about, is Amir's seeming preference (not a criticism, everyone has a preference!) for relatively higher distortion speakers. He loved the Revels, and both of them drive distortion levels above preference, just below 500 Hz. Now, he loves this one, and the distortion is fairly terrible across the entire audio spectrum. This leads me to believe that some folks really do enjoy the sound of distortion, that ratio where the main signal is swamped by other frequencies not in the original recording.

However, if critically listening to a speaker that is reproducing a recording of acoustic instruments, a quartet perhaps, whereas the distinct timbre of instruments can be realized, would that preference still hold? I would imagine that would not be the case, as I'm certain you would mask many of the instruments' qualities in THD.

Finally, how does THD impact imaging? I would imagine that it would blur the soundstage a bit, compared to a well designed, low distortion piece of equipment.

I have noticed a few Amir preferences that are a little different than my own(wide dispersion), but I haven't noticed a preference for higher distortion. I think he probably preferred this speaker in spite of its poor distortion, not because of it(due to the excellent FR and directivity). What other speakers in this price range are you looking at that Amir didn't recommend that led you to believe he prefers more distortion? There have been speakers in this range with better distortion performance, for sure, but I'm fairly certain that it was at the expense of worse on and off axis frequency response.

From what I've read, and based on personal experience, frequency response and directivity are much more important than distortion. I would guess that a speaker with slightly better FR/Directivity will be preferred over a speaker with moderately less distortion.
 
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RayDunzl

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So in general you can't compare the distortion figures for near-field use against far field.

Experiment:

JBL LSR 308
"Normal" room noise
Simultaneous measurement, single speaker active
About 82db SPL at listening position

Mic 1 at Listening Position
Mic 2 hanging over the front of the speaker, so the capsule is in the plane of the front of the cabinet - more extreme than the Klippel measurement position, but I don't have a stand to hold the mic where I might like to put it.

Using dBc setting - graph sets tone level received to 0dB, to allow comparison of levels of noise and distortion relative to the tone


1604864679643.png


Tone and harmonics are much higher relative to room noise in the close measure

Third harmonic just peeking out of the noise floor at the listening position

Disclaimer: quick test, not trying to make it look bad or good, there will be variations with frequency and the phase of the harmonics (levels will change) at the listening position. Take the measure with a little suspicion, but useful to illuminate the basic idea.

I set it up, frequency selection - random, at least, nothing specific and no tuning - saw harmonics at the speaker, raised amplitude until one of the harmonics peeked out of the noise floor at the listening position.
 
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Xyrium

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I don't have a preference for distortion. Indeed I clearly noted in the review that distortion sets in as you turn the volume up. The 86 dBSPL is quite loud so it is well into distortion range but when listening one can obviously listen at much lower level since these are used near-field. So in general you can't compare the distortion figures for near-field use against far field.

Thanks Amir. It could be my own confusion in understanding the subjective anecdotes. I was under the impression that you listen at higher levels than 86dB at your listening position, nearfield or otherwise, based on previous reviews. As such, your measurements of the 308's even at the nearfield level, indicate that these are injecting a significant amount of harmonic distortion into the sound.

Therefore, regardless of whether you listened nearfield or afar, I would imagine you'd be hearing even more of that distortion than what the Klippel measured.

However, you may indeed be a closet tube amplifier enthusiast. ;)
 
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