[TimHKG]

Thanks for your advices, GC!

I think the hiss noise coming out from the tweeters is kind of thermal noise. It was said that this kind of noise cannot be completely eliminated, just only to diminish it to a very low level by using well-designed PCB accompanying high-quality transformer and low-noise components!

I do find 2 pieces of ferrite cores(not sure it's made of Mn-Zn, Ni-Zn...etc.)left behind in my tool box. I'll put them onto the wires connecting to the tweeters as well, to see whether they could generate any positive effects. However, need to open up the speakers again...time-wasting...sigh!

 

[GCKelloch]

That's not them. They are ~1/4 thick doughnut shaped ceramic magnets. The wires are wrapped around each one several times. Maybe just separate them as I said, but it might not make any difference. They may just be there to pass a computing device inspection.

My PC noise overpowers the speaker hiss with the volumes at 7. I'd leave them at 7 for best SNR. That's generally about the max level b4 distortion with your A/I and software outputs maxed. You might even get some transient distortion then. I just swapped the PSU hoping it would be quieter. The fan whine is thankfully gone, but still ~20dB wide band noise at my listening point from the three total "quiet" fans together. Time for a laptop or something, I guess.

 

[TimHKG]

Unfortunately, it doesn't help!

So, I may just set the volume at 6 or 6.5 and leave it as is.

 

[GCKelloch]

There is no reason to put the extra choke on there. Chokes are supposed to be designed specifically for devices they are used on. The inductance of that extra choke could affect the freq response. I'd remove it.

Not that it will necessarily help, but the original chokes are still stuck together. The idea is to separate them with separate ties. Probably should keep them away from components as well. Again, may not make any difference.

Incidentally (and a bit off topic), I had a hunch when installing my new PSU that having it touching the lip on the case designed to hold it up might possibly amplify the fan noise in the case from more surface area contact with the bottom panel the fan is attached to. So I moved it up off the lip and the noise at my listening point went down to ~17dB. I then connected the system fan to the silent mode input, like I should have done b4. Even though it runs at less than 1/2 the RPM in silent mode, it doesn't make a significant difference. I disabled silent mode on it more hot air will evacuate out the case rather than up into the PSU. Still, the ~3dB noise level gain was worth it.

If that's not obsessive enough, I keep two full soft CD cases on top of the PC case to damp case vibrations. I can shape the noise by moving them around. Perpendicularly across the center seems best -- more force on the top case sides, and the area over the PSU is open for better heat dissipation. One day I may set up a noiseless system with only heat-pipes, or just get a quiet laptop, but I make use of the full AMD 4GHz 8-core power now.

 

[TimHKG]

Previously, I'd had just the original 100uF 450V replaced with 220uF 450V and the fuses as well, also some original ones with extra film capacitors attaching onto them as speed-up capacitors

And now just hesitating on whether doing a re-capping of the whole board of LSR305 since I'd made a inventory check and do find some amount of unused capacitors left behind in the tool box. However, don't know whether it's worthy of spending times on it cause the good result is quite unpredictable.

 

[LazyListener]

Seems this has turned into a modding thread. I don't have a detailed review. I will say that what I liked about the LSR305s was their fairly neutral and accurate response, and the deep bass extension. Imaging was decent, but not nearly as great as the KEF Q100 and Q300. Would have liked more detail and clarity. These are better for nearfield listening than for anything beyond several feet.

Edit: I forgot to mention something else that bothered me about the 305s. Dynamic range. The DR sounded somewhat compressed, as if intentional, to make all the sounds within a track more audible. Classical music sounded more compressed than with the KEF speakers.

Does anyone know if these use some sort of DR compression or limiter?

 

[Music Alchemist]

Not sure why this thread is in Computer Audio. Anyway, the LSR305 caused me to get rid of nearly all of my headphones. (Owned five figures worth of 'em. See profile.) I haven't bothered with room treatments or EQ, but it's already the most realistic sound I've had in my bedroom. (I'm sure that will change once I upgrade to better speakers.) Below is the latest photo I took. I've experimented with positioning in the room, and this is the best setup I've found. (And the sound is leagues better with Chord DACs such as the Mojo and 2Qute. I can hardly enjoy entry-level DACs anymore.)

 

[castleofargh]

moving away from the wall on the left was probably a good idea. the angle seems wide, but coming from headphones maybe the 60° panning is still too much for what you're used to? ^_^

 

[Music Alchemist]

moving away from the wall on the left was probably a good idea. the angle seems wide, but coming from headphones maybe the 60° panning is still too much for what you're used to? ^_^

Yep, I've experimented with the positioning quite a bit. What I have right now isn't the generally recommended equilateral triangle, but is instead both wide and intimate, so I get more physical energy along with expansive imaging. I'll have my first floorstanding speakers (Klipsch RP-250F) next week, so I get the feeling I won't be keeping the JBLs despite how much I love them.

 

[AxelCloris]

Cleaned up the thread. Please keep posts within the posting guidelines.

 

[Francisk]

I'm eagerly waiting for my LSR30X to arrive soon.

 

[germanium]

Not sure why this thread is in Computer Audio. Anyway, the LSR305 caused me to get rid of nearly all of my headphones. (Owned five figures worth of 'em. See profile.) I haven't bothered with room treatments or EQ, but it's already the most realistic sound I've had in my bedroom. (I'm sure that will change once I upgrade to better speakers.) Below is the latest photo I took. I've experimented with positioning in the room, and this is the best setup I've found. (And the sound is leagues better with Chord DACs such as the Mojo and 2Qute. I can hardly enjoy entry-level DACs anymore.)

Is that a basically square room? If it is you could place the system in one corner facing the furthest corner & that reduces room anomalies to the point of not really needing room treatments in many situations. If you look at my photos at the beginning you can see that is what I did & it sounds absolutely great. Better than any other placement in square rooms that I have tried.

 

[JonWalter]

I just wanted to throw my 2 cents in about the JBL LSR305s.
I have been using them for roughly 3 weeks, and I know I will get obliterated on these forums for my assessment, but I am going to go ahead and tell you to save the money, and buy the JBL's.
I have a small home studio, and could not afford to have the desk space taken by getting any 8" monitors that are BEHEMOTHS in my opinion.
With that being said, I just want to let you know that theses speakers are the deal of the year. Although not as loud as some competing monitors (41watt HF, 41Watts LF) they definitely make up for this with their crystal clarity on the high frequencies. In these JBLs their engineers decided to use a wave guide for the tweeter that in my opinion is beyond anything that we have ever seen in a budget monitor. Tonally they are incredible, and well worth twice as much as they are asking. These are the same wave guides as they use in their upper echelon products, and it pays off.
I challenge anyone to go out and listen to these monitors and tell me that any budget monitors come even close to the JBL LSR305.
Regards Jon Walter.

 

[randytsuch]

I recently got a pair of LSR305s, letting them break in now, but they sound promising.

There is a thread at diyaudio on mods to the 305. Its at the bottom of this page, changing a few important caps.
http://www.diyaudio.com/forums/multi-way/320206-jbl-lsr305-tweaking-6.html
In the beginning of the same thread, another guy added a brace inside the 305.

I'll probably make these changes after they break in.

Randy

 

[germanium]

I just wanted to throw my 2 cents in about the JBL LSR305s.
I have been using them for roughly 3 weeks, and I know I will get obliterated on these forums for my assessment, but I am going to go ahead and tell you to save the money, and buy the JBL's.
I have a small home studio, and could not afford to have the desk space taken by getting any 8" monitors that are BEHEMOTHS in my opinion.
With that being said, I just want to let you know that theses speakers are the deal of the year. Although not as loud as some competing monitors (41watt HF, 41Watts LF) they definitely make up for this with their crystal clarity on the high frequencies. In these JBLs their engineers decided to use a wave guide for the tweeter that in my opinion is beyond anything that we have ever seen in a budget monitor. Tonally they are incredible, and well worth twice as much as they are asking. These are the same wave guides as they use in their upper echelon products, and it pays off.
I challenge anyone to go out and listen to these monitors and tell me that any budget monitors come even close to the JBL LSR305.
Regards Jon Walter.

For the most part I agree with you very much. I do take exception to the claim of being not as loud as competing monitors especially of this size. More amp power does not always mean louder. These speakers play as loud as any other in it's size category, even against other with more amp power. This is due to the efficiency of the drivers, the larger size of the cabinet & the slipstream port. The power ratings of the amps are wrong though which I found common practice on some of these nearfield monitors. The woofer output is closer to 50 wats & the tweeter is closer to 30 watts due to impedance of the drivers. I believe the overall rating however is correct.

Part of what makes the woofer efficient is the large size of the magnet & low mass of the driver cone structure itself. If they had not however given it a larger cabinet & slipstream port the large magnet would have caused a significant loss of bass as oversize magnet will cause a loss of sensitivity in the bass without other corrections due to back electromotive force created by the huge magnet. Many people assume that porting a speaker makes it more efficient but this is not the case, especially if balanced frequency response is required. It is mainly the drivers that determine the efficiency of the speaker , not the port. The port though allows the use of a driver that is more efficient & still retain good low frequency extension in a good design.