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JBL 308P MKII Studio Monitor Review

RayDunzl

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georgew2

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what is the minimum acceptable distance of wall? could be problem placing the speaker near 20cm from the wall?

Thanks!
 

FTB

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what is the minimum acceptable distance of wall? could be problem placing the speaker near 20cm from the wall?

Thanks!
And if you use the boundary EQ at -3 dB ?
IDK, just a suggestion.
 

svenz

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I bought these with the LSR310s to use as a home theater 2.1 setup for the last 3 months or so. I think I'm at the point of selling them though - they simply don't get loud enough! And this is in a small/med room (3mx5m), about 2.5m away. Like the review says, the amplifier is really lacking. The worst aspect is when watching some multichannel movie content that gets quieter when downmixed to 2.1, and I have to crank everything to basically 100% to get it audible. There may be some hacks around this (like boosting volume to >100% digitally at the source) but for HT I think it's just too much a pain. If I was using them for nearfield only I'd probably keep them.
 

Robbo99999

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I bought these with the LSR310s to use as a home theater 2.1 setup for the last 3 months or so. I think I'm at the point of selling them though - they simply don't get loud enough! And this is in a small/med room (3mx5m), about 2.5m away. Like the review says, the amplifier is really lacking. The worst aspect is when watching some multichannel movie content that gets quieter when downmixed to 2.1, and I have to crank everything to basically 100% to get it audible. There may be some hacks around this (like boosting volume to >100% digitally at the source) but for HT I think it's just too much a pain. If I was using them for nearfield only I'd probably keep them.
That's weird, I use them for TV/movie watching in a simple 2-channel setup, as well as for music listening at over 2 metres in I guess a medium sized room, and I rarely use them above the 9th indent, normally on the 7th - and there's 20 indents, so I never use them above half volume, and that's plenty loud for me whilst using a -3dB preamp too......that's with a 2V DAC for music listening and whatever my TV can output at max volume through it's connection which I worked out is less than 0.9V after it's gone through my miniDSP 2x4 processor (-1.5dB preamp built into it's EQ).
 
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respice finem

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I'm contemplating getting these for a simple TV based stereo setup.

A question to actual owners / users: Is the idle noise of the 308P a problem? There are conflicting statements about this on the Net.
Another question: Some say they do have auto standby? (some say the noise disappears after some time).

The other option would be Adam T8V, allegedly almost noise-free but some find the treble annoying...
 

Chromatischism

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I bought these with the LSR310s to use as a home theater 2.1 setup for the last 3 months or so. I think I'm at the point of selling them though - they simply don't get loud enough! And this is in a small/med room (3mx5m), about 2.5m away. Like the review says, the amplifier is really lacking. The worst aspect is when watching some multichannel movie content that gets quieter when downmixed to 2.1, and I have to crank everything to basically 100% to get it audible. There may be some hacks around this (like boosting volume to >100% digitally at the source) but for HT I think it's just too much a pain. If I was using them for nearfield only I'd probably keep them.
If you don't have the source volume at 100% then that could be the problem.
 

FrantzM

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That's weird, I use them for TV/movie watching in a simple 2-channel setup, as well as for music listening at over 2 metres in I guess a medium sized room, and I rarely use them above the 9th indent, normally on the 7th - and there's 20 indents, so I never use them above half volume, and that's plenty loud for me whilst using a -3dB preamp too......that's with a 2V DAC for music listening and whatever my TV can output at max volume through it's connection which I worked out is less than 0.9V after it's gone through my miniDSP 2x4 processor (-1.5dB preamp built into it's EQ).
Same feelings. I have 3 LSR 308 in a room of similar area. Gets loud beyond my tolerance and frankly that of many, with 2 LSR 305 as surround, I have reached, on an experiment, above 112 db. That’s loud in any book. I posted the results somewhere in ASR. It was unbearably loud. Something is not set up correctly.

Peace.
 
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FrantzM

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I'm contemplating getting these for a simple TV based stereo setup.

A question to actual owners / users: Is the idle noise of the 308P a problem? There are conflicting statements about this on the Net.
Another question: Some say they do have auto standby? (some say the noise disappears after some time).

The other option would be Adam T8V, allegedly almost noise-free but some find the treble annoying...
Depends on how far you sit and, of course, background noise. At 2.8 meters, my seating position, I can't hear these with the background noise at 40 dB c-weighted measured on an iPhone 11 and the dBMeter app. At the same distance and background noise, I seem to notice that of the LSR305. I will perhaps measure and report but I never cared about their background noise.
I may be biased: I own and love them. They are true bargains, In a small room with a pair of cheap but capable subwoofers and DSP (See Sweetchaos Subwoofer Comparison) . You can be in full range and accurate Audio Heaven.

Peace
 

Robbo99999

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I'm contemplating getting these for a simple TV based stereo setup.

A question to actual owners / users: Is the idle noise of the 308P a problem? There are conflicting statements about this on the Net.
Another question: Some say they do have auto standby? (some say the noise disappears after some time).

The other option would be Adam T8V, allegedly almost noise-free but some find the treble annoying...
Hi, I think these are good speakers for TV/movie use, they have good smooth directivity so provide a uniform experience off axis, and they've got a good frequency response curve too, but you'll want to put the HF Trim Switch on the back of the speakers at -2dB to make it an even flatter anechoic response.

Idle Noise is a problem on these speakers if you're not playing content and your listening position is say 1.5m/1m or less - for instance I wouldn't want to use them on a desk as speakers used for computer speaker use as the long periods of idle and close proximity of the speakers means you would hear a constant hiss from them. At 2m I certainly can't hear any hiss when idle. Under 1m you will definitely hear hiss at idle. The hiss never gets worse, never gets any better, and it's not related at all to the volume knob position on the back of the speaker - well it disappears at minimum volume but that's because it's a "mute" position where zero sound comes out of the speaker even if you play music through it.

Auto Standby you ask. Yes, they have autostandby, and they take quite a long time to turn themselves off after no content is played - and to be fair sometimes they "get bugged" and don't shut themselves down at all. I have disabled the Auto Standby function on mine as it is bugged as I mentioned, and also it just felt like a cleaner option running the speakers without Auto Standby given I knew it was a bugged function, didn't want it somehow interfering in other aspects of the speaker's performance (if it could, probably wouldn't interfere, but it was annoying me so I turned off that function). In the instruction manual it explains that there's a sequence of button pushing you have to do on the back of the speaker to turn off Auto Standby - it's easy to do, just you have to find that passage in the manual & carry out the procedure, simple really.
 

FrantzM

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I bought these with the LSR310s to use as a home theater 2.1 setup for the last 3 months or so. I think I'm at the point of selling them though - they simply don't get loud enough! And this is in a small/med room (3mx5m), about 2.5m away. Like the review says, the amplifier is really lacking. The worst aspect is when watching some multichannel movie content that gets quieter when downmixed to 2.1, and I have to crank everything to basically 100% to get it audible. There may be some hacks around this (like boosting volume to >100% digitally at the source) but for HT I think it's just too much a pain. If I was using them for nearfield only I'd probably keep them.
Re-reading your post this is not the fault of the 308. Many movies dialogs are mastered too low. You have to really crank up the overall level to hear these well. or, if you have an AVR and a discrete center channel, raise the level of the center channel for intelligibility, with the results of ruining the audio Multi channel audio reproduction... when things get even moderately loud... Amir posted about this in ASR.
Peace.
 
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svenz

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I'll have to experiment more then, hmm. I'm going Plex on nvidia shield -- (usb) --> SMSL SU-8 (at 100% volume) -- (balanced) --> LSR310 at -10db sensitivity/60% -- (balanced) --> 308p at -10db/100%.

I think it is most likely an issue w/ Plex downmixing 5.1 and the volume levels dropping.
 

Robbo99999

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I'll have to experiment more then, hmm. I'm going Plex on nvidia shield -- (usb) --> SMSL SU-8 (at 100% volume) -- (balanced) --> LSR310 at -10db sensitivity/60% -- (balanced) --> 308p at -10db/100%.

I think it is most likely an issue w/ Plex downmixing 5.1 and the volume levels dropping.
See if you've got anyway of visualising the dBFS level after Plex is downmixing, after which point maybe you can find a way to digitally boost all frequencies so it's closer to 0dBFS whilst leaving enough headroom to ensure you don't get digital clipping, but don't know enough about your setup to know if that's possible.
 

respice finem

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I'm contemplating getting these for a simple TV based stereo setup.

A question to actual owners / users: Is the idle noise of the 308P a problem? There are conflicting statements about this on the Net.
Another question: Some say they do have auto standby? (some say the noise disappears after some time).

The other option would be Adam T8V, allegedly almost noise-free but some find the treble annoying...
Follow-up: Now I got them, and well, in a desktop setup the hiss would possibly be a problem, I can hear it up to 1,8-1,9 m away.
No hum or such, just "pink noise" like hiss. A non-issue for the intended use case, however.
 

Robbo99999

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Follow-up: Now I got them, and well, in a desktop setup the hiss would possibly be a problem, I can hear it up to 1,8-1,9 m away.
No hum or such, just "pink noise" like hiss. A non-issue for the intended use case, however.
Don't forget to flick the HF Trim Switch to -2dB as a quick rough optimisation, makes them more anechoic flat. Or if you've got the ability to apply parametric EQ, then you could try my EQ that turns Amir's measurements of these speakers to a smooth Listening Window and at the same time a flat on-axis response (Anechoic EQ) - listed in my post here:
If you try my parametric EQ out then make sure you have the HF Trim Switch on the back of the speaker at it's default 0dB position.
 

respice finem

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Don't forget to flick the HF Trim Switch to -2dB as a quick rough optimisation, makes them more anechoic flat.
This was what I did spontaneously, after just putting them on a table to test for function :) because the default treble was slightly too much for me. The final setup will be in a few months in my house in Poland, to which I'll be moving back from Germany. I decided to buy early, just in case...
 

Robbo99999

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This was what I did spontaneously, after just putting them on a table to test for function :) because the default treble was slightly too much for me. The final setup will be in a few months in my house in Poland, to which I'll be moving back from Germany. I decided to buy early, just in case...
Nice. (I edited my previous post while you were typing your reply - added a point about parametric EQ and a link to it.)
 

Robbo99999

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Well, there is that gain control in the back so I don't have absolute levels. I set it to 0 dBu for the 96 dBSPL with the gain setting near what you see in the picture.
Hi Amir, just trying to optimise the levels going into the back of my 308p mkii speakers, and have a question. I did some googling, you mention 0 dBu, and I found out 0dBu is 0.775V (RMS). From your picture you have the speaker on -10 dBv which I've found out through googling is the equivalent of 0.3162V (RMS) as a standard. If using this speaker with modern DACS that output 2V RMS then do we need to make sure we dial it down digitally to output the 0.3162V as a max when used on the -10 dBv setting, or would we also be safe using at 0.775V output (like you did) for the -10 dBv setting on the back of the speaker, or even higher voltage? This is in reference to you noticing clipping at high input levels.
JBL 308P MkII Review Powered 8 inch Two-Way Studio Monitor Back Panel XLR Input.jpg



(and the schematic pic of back of back of speaker follows)
308p back of speaker.jpg


(Before my research into the +4dBu and -10dBv settings for "Input Sensitivity" (as seen in schematic above) and what they referenced in terms of voltage I'd figured this speaker was supposed to take the 2V of modern DACs when on the consumer DIP switch of -10dBv on the back of the speaker.....but that seems not the case as it seems that -10dBv means you should set the DAC to input no more than 0.3162V as that is the standard, and +4dBu I found would mean a standard of 1.228V only?)

EDIT (days/weeks later): well it does say in the manual that this speaker can cope with 2V input on the consumer -10dBv setting, but there's no way of knowing at what voltage level Amir recognised the distortion as he didn't know (and/or say) - for his tests he used an input voltage of 0 dBu or in other words 0.775V so it would be "safe" to use at least that much. I've got it setup now to input a max of 0.775V into the back of my speakers because of this, I don't need the extra volume that would be afforded by upping it to 2V as the room is not massive and I don't listen particularly loud. (I think I'm around the halfway point on the volume knob position on the back of the speakers).
 
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gtgray

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I'm contemplating getting these for a simple TV based stereo setup.

A question to actual owners / users: Is the idle noise of the 308P a problem? There are conflicting statements about this on the Net.
Another question: Some say they do have auto standby? (some say the noise disappears after some time).

The other option would be Adam T8V, allegedly almost noise-free but some find the treble annoying...
I just picked up a pair of these from Amazon at $199 each. Mine are dead quiet when idle. I got them 4 days ago. This thread has been very helpful. They were too bright with the HF switch at the stock position. The -2 dB setting is great. I really like them. Currently feeding them via Chromecast Audio analog. Have the SMSL DO100 Dac on the way,
 

respice finem

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I just picked up a pair of these from Amazon at $199 each. Mine are dead quiet when idle. I got them 4 days ago. This thread has been very helpful. They were too bright the HF switch at the stock position. The -2 dB setting is great. I really like them. Currently feeding them via Chromecast Audio analog. Have the SMSL DO100 Dac on the way,
Have you bought the JBL or the Adam? I guess the latter - I got the JBL and the idle hiss is quite noticeable (until the standby kicks in, which allegedly only the CE labeled version has). At very close distance (<1,5m) the idle noise would be a bit annoying to me.
 
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