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JBL 306P MK II Review (Studio Monitor)

Fuzziekiwi

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Try the Revel bookshelves: M16, M105, or M106
Scored an M16 for $360 open-box. Curious as I've never heard any of the Revel line but heard great things.
 

Germanium

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Scored an M16 for $360 open-box. Curious as I've never heard any of the Revel line but heard great things.
Revel is one of the brands under the same umbrella as Mark Levinson. It is a high quality brand. I believe these brands were bought by Harman which was later bought by Samsung along with JBL
 

Hewbacca

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My data points now owning 305p and 306p.

My 305p are connected to a Fiio K5 Pro, I keep the knobs on the back of the speakers at 6/10, and there is no hiss. If I turn the knobs up to 10/10, and put my ear right next to the drivers, I can detect a very quiet hiss. I can not hear it in my normal listening position which is about 3 feet from the monitors (computer setup).

My 306p are connected to my Onkyo receiver in my home theater setup. There is a horrible hiss all the time, really more of a buzz than a hiss I'd say. It doesn't affect my enjoyment of the speakers because I don't notice it when watching TV or movies, but when the TV is off I can hear it if I'm in the room. The previous set of speakers I had in that setup were passive Bose speakers from 20 years ago, and there was no hiss, so I tend to not think it is anything further up the audio chain (fwiw I am using the same brand and model of cables).

This would lead me to conclude either 1) the 305s don't suffer from this issue and 306s do, or, it is a unit to unit variation.

For my purposes, I got the hiss in the place it doesn't bother me, cause if my computer speakers were hissing all day it would drive me insane.

Otherwise, love both sets of monitors. Truly opened my eyes to the world of monitors.
 

roci_big_ear

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I am almost certain that the hiss is switching noise induced into the analog path. By measuring things with the oscilloscope, I can see that the noise is actually very strong but mostly above the audible range.

The difference is that the 305's have lower supply voltage and amp gain, which I think is what makes them better in that respect.
 

daftcombo

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My data points now owning 305p and 306p.

My 305p are connected to a Fiio K5 Pro, I keep the knobs on the back of the speakers at 6/10, and there is no hiss. If I turn the knobs up to 10/10, and put my ear right next to the drivers, I can detect a very quiet hiss. I can not hear it in my normal listening position which is about 3 feet from the monitors (computer setup).

My 306p are connected to my Onkyo receiver in my home theater setup. There is a horrible hiss all the time, really more of a buzz than a hiss I'd say. It doesn't affect my enjoyment of the speakers because I don't notice it when watching TV or movies, but when the TV is off I can hear it if I'm in the room. The previous set of speakers I had in that setup were passive Bose speakers from 20 years ago, and there was no hiss, so I tend to not think it is anything further up the audio chain (fwiw I am using the same brand and model of cables).

This would lead me to conclude either 1) the 305s don't suffer from this issue and 306s do, or, it is a unit to unit variation.

For my purposes, I got the hiss in the place it doesn't bother me, cause if my computer speakers were hissing all day it would drive me insane.

Otherwise, love both sets of monitors. Truly opened my eyes to the world of monitors.
Did you try swapping cables (including power cables) between them to see if the hiss remain?
 

Hewbacca

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Ok I just did a bunch of experimentation and the issue is a ground loop associated with my Denon receiver. NOT the JBL's fault. When the receiver is on the buzz goes away (tweeter hiss remains). Also when I swap the speakers with another setup (run off a Fiio K5 Pro), there is no buzz, just tweeter hiss. Disregard my complaint of the buzz, but they do have a hiss that is only audible (to my 37 year old years that can hear up to about 15-16khz) if my ear is next to the tweeter.

Edit to add: Completely resolved the buzz issue by flipping the little input sensitivity switch on the back of the monitors.
 
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Blew

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I am almost certain that the hiss is switching noise induced into the analog path. By measuring things with the oscilloscope, I can see that the noise is actually very strong but mostly above the audible range.

The difference is that the 305's have lower supply voltage and amp gain, which I think is what makes them better in that respect.
I can hear hiss on my 305p MKII's at up to about 1m away. It is a constant volume regardless of volume or switches at the back of the speakers or the input. It's noticeable even with background noise, but it doesn't bother me as I don't notice it when playing music unless it's at a very low volume.

Re distortion, I find that the 305p's are slightly distorted when set from around 3/4 to full volume on the speaker volume dial. ie when using the speaker's internal amp.
I find these speakers have lower distortion when I use my Singxer SA-1 as a pre-amp with the 305p's are set to 1/2 volume maximum, so that most of the amplification is done by the SA-1. I just have to remember to reduce the volume on the SA-1 when switching to headphones!
 

Smislov

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Can JBL 306 be placed in 9m2 room and listen to 2-2.5m far from speakers? My second setup in my baedroom :) Tnx
 

YSC

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Can JBL 306 be placed in 9m2 room and listen to 2-2.5m far from speakers? My second setup in my baedroom :) Tnx
should be fine for the listening distance, I am using in my living room similar in size for TV speaker in similar 2m listening distance, the KRK RP5 G4 need medium gain and low volume from my TV for both movie and games
 

Smislov

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should be fine for the listening distance, I am using in my living room similar in size for TV speaker in similar 2m listening distance, the KRK RP5 G4 need medium gain and low volume from my TV for both movie and games
Tnx… Today I have listened experience with R5 G4 and i hope that to end of this week I will also listen Adam T5v in same shop. Better sound if I’m closer to speakers, and separation I think was not so good, with little sharp sound. My personal opinion:(
 

Palladium

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I'm curious if there are any bookshelves with a similar sound to the LSR series. They're just a very fun speaker to enjoy music imo and have that open high end without being harsh for me. My main thing with ELACs are that the treble sounds dull unless you blast them, they have a pretty warm sound sig.

I've tried:
RP-600M (Returned- fantastic imaging/guitars but too bright overall)
KEF Q150 (Returned- fantastic imaging but sibilance)
Debut B6 (Kept)
Debut Reference (Kept)
Wharfedale Diamond 11.1 (Returned- nice mid range and bass didn't quite like the treble)
JBL Studio 530 (Returned- metallic sounding treble and downgrade from DBR)

Not only that, they also manage to do it at low SPLs alongside superb soundstaging.

I had the Kali LP-6v2 which is objectively superior than the my 305P in FR and THD. Yet they were the dullest speakers I had owned at my usual 60dB SPL listening levels. Hated them and luckily I was able to sell them at a tiny loss.

Then I took the money and spent them on a cheap used pair of 306P and I'm again blessed in the land of wonderful LSR sound. Seems to sound a bit warmer than the 305P.

Another thing I noticed is my 306p doesn't seem to support the auto-standby function. I tried enabling it following the user manual and it doesn't work.
 
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