Distortion or reduction of imaging/details? I can't imagine these things distorting unless driven to the extreme, or poor source material.

Interesting discussion of near-fields vs mid-fields:

Near-Field Monitors VS Far-Field vs ?

Maybe Scott means that to fill his present room, the JBL would have to be cranked up too high to be of any good use? Thanks for the article!

I guess he had it cranked.

Exactly, I also still have the jbl 305's and the airmotiva 6's.The jbl's in there usuall or appropriate use are fine, as a matter of fact very fine. They are even very good at mid field BUT, My room is 12 foot six inches wide, which is not the problem as the jbl's are less than 6 feet apart with a 310 sub on each side!
The prblem is my room is in excess of 20 feet deep and open to a fourier on one side after some wall space.
The jbl 305's along with a sub on each side will hold up there own at moderate to high listening levels. By themselves the 305's just can't do what the air 6's can.
I have also learned "once again" to not burn in new equipment together all at once. The streamer hd dac and with appropriate power isolation along with everything else is starting to sound wonderfull indeed! Now I have to decide wether to keep the air6's or return them. I think I will keep them along with the 310 subs and move the 305'sto my personal computer room which is WAY smaller. Damn now I have to purchase another dac LOL!

Wow...I read the first few pages of this thread & damn,how I wish I had read through this before I had bought my Tannoy 502's(for obvious noise issues)...but I am actually here to chime in on how elated I am about the 305's!

3 hours after I had received my Tannoy's via UPS,I had them packed up and ready to be shipped out for a return.
I then immediately placed an order for the LSR305's and for the last couple of days,I have been immersed in a sonic Xanadu!

Initially,I was very skeptical of the 305's...not only for their meager price,but I thought the LF spec of 43Hz was absurd.
I recently had to replace my PC,change ISP's,buy a printer,a cable modem...etc.,...so my monitor budget was paper thin and I had to replace my Adam A7's,as their mid range clarity was a sick joke,for the price!

That being said,the JBL's were the absolute best monitor purchase I have ever made in the last 10 years,because in terms of saving space,improving mid range clarity and stereo width(& saving a wad of coin in the process),the JBL's outperform my old $1,000 pair of A7's and I promise everyone reading this,that I tell the unbiased truth.
As for the LF response...well...for the first day,I listened to the 305's with the shelving switch on the neutral setting and the low end was adequate...but oh man...once I switched to the +2 setting,I was blown away!
Deep,well rounded & tight bass...but not overblown at all....an absolutely immaculate level of bass for my treated,12' X 13' room!
I don't imagine that the 305's roll off point is 43Hz,but to my ears,I'd say they easily reach 50Hz,if not say....48Hz,or thereabouts.

I can't wait to receive my Auray IPRS-M Recoil Stabilizer pads on Monday,to optimize my JBL's!

Thanks for he helpful info!

I am about to place an order. Sweetwater has them for $119! However since I'm in Canada, the "brokerage fees" is always an unknown factor.

LOL!!! For a week I've been wondering about this sentence until it finally hit me that you have a "foyer" on one side of the room! Now I'll sleep better!

Well, I followed the advice of a few people and decided to treat my room, before moving to other monitors. So I built myself a couple corner bass traps, using UltraTouch insulation (non-toxic, recycled denim). They stand 4 feet tall and look a bit weird, but they work!

Next I played with the settings on the back of my monitors - Yamaha HS80s - and suddenly my monitors started delivering a sound I had never heard from them in 3 years. I'm actually not going to need anything else for now. The remastered album now sound clean and solid now, not boomy and wobbly like it did last week.

Thanks to all the tips and information gained here, this is a great pool of knowledge and experience! If only we act on that knowledge... hum hum...

Regards,

Andre

I'm planning to add a couple homemade Home Depot supplied UltraTouch insulation bass traps. What did you use for plans?

I'll make a drawing and send a couple photos tomorrow. I'm not sure you'd want to follow my example, but eh, I did my best with what I had... No holes in walls, no wood cutting, no glue, no nails, no screws.

It's working, although I can't scientifically measure. But enough so i could notice.

Regards,

Andre

OK, czoli, IF the UltraTouch you get from Home Depot is pre-cut, square or rectangle, you may find this video below to be very helpful in your case:

How To Build Corner Bass Traps Floor To Ceiling

If not, then I personally had left-over batts, 8 feet long by 2 feet wide and 5.5 inches thick.

Like I said, this is the poorest of the poor-man's bass-traps, but they do work for me in my case. Regular room size, 10.5 X 9.5 feet.

M A T E R I A L:

- 4 suspended ceiling tiles 2 x 4 Link: 2-ft-x-4-ft-Lay-in-Ceiling-Tile

- UltraTouch insulation (96 inches X 24 inches - I used two whole ones, vertically layered. I cut 1/3 off of one and folded the 2/3 left. Put the 1/3 first and pushed the 2/3 in front. Same thing with the second layer)

- Zip ties, medium size, about 10 inches long

- 4 X White Eggcrate T12 Troffer Replacement Diffuser (you may want to get more just in case you break them). Link: White Eggcrate

- Aluminum/Foil tape 1 roll Link: Foil tape.

- Ram Board (I had clean left overs, so you could use anything you'd want to cover the top). Link: Ram Board.

Here are the steps I've taken.








I slid mine back against the corners "gently" as my floor is wood. If you have carpet, I suggest you build your traps on something you can drag on your carpet so as not to break them when you push them in place.

Hope this helps! They may not be pretty, but they work for me. If I was more gifted with power tools, I'd spend more time on this.

Andre

Thanks so much Andre, very cool! I love the idea of using UltraTouch as well.

Haha.. that's about the craziest DIY design I've seen Andre! If this is the kind of design you come up with I'd be quite interested to hear the kind of music you make. You are clearly one for thinking outside the box!

It's best not to use Ultratouch in thicknesses over 4" though. Above that you'll get better results with other materials. It's great stuff for side wall panels.

At 5.5" you already see Ultratouch stops adding LF gains. Absorption coefficients for Ultratouch in 3.5" vs 5.5":

R-13 3.5" (mm) 125hz: 0.95 250hz: 1.30
R-19 5.5" (mm) 125hz: 0.97 250hz: 1.37

Some people don't want to put more fiberglass into their house in a room they're in constantly. So ultratouch is an alternative with similar specs to fiberglass.

It's not similar to fiberglass in performance at all though. As you can see by the absorption spec, going beyond 4" you no longer get significant absorption gains. At 3.5" you get better performance than fiberglass though. It's fantastic stuff but only to use in a single layer. You can also use it as the outer layer of your trap and place low density fiberglass or rockwool behind it for a good result.

Rockwool is completely safe to use as well as Knauf Ecose products. I never recommend rigid fiberglass like Owens Corning personally unless someone already has it.

I'm seriously considering the LSR305's. However, is there a problem with feeding the signal into these monitors with an unbalanced lead that will be no more than 3 metres long?

Thanks for the compliment, nms...

The graphics you see are not perfectly as the real thing. Inside, the bats are not tightly stuffed, there a bit loose. Hope it will be OK for absorption. I'm thinking it will allow more movement for the sound to be softly absorbed. So far anyways, it's like I am discovering my monitors for the first time since I got them 2 years ago to replace Rokit 8 Gen2.

I see that EquatorAudio sells Sound Absorption Panels made with recycled denim too:


*******
QUOTE:
A Noise Reduction Coefficient (abbreviated NRC) is a value given to a sound energy when it strikes a particular surface.

A lower NRC number indicates more reflection and the less absorption. A higher number indicates less reflection and greater absorption. An NRC of 0 indicates an unaffected, perfect reflection; an NRC of 1 indicates perfect absorption. Because of the formulas used, the coefficient is not a percentage and as such; values larger than one are possible. Those values indicate additional absorption beyond complete.

The FB/E 1’ x 2’ Sound Abatement Panels feature a 2”, 2 pound density, layered cotton absorption material with an NRC rating of 1.05
Another method of rating the absorption properties of material is the Sound Absorption Average (SAA) which averages one-third octave bands.

The FB/E 1’ x 2’ Sound Abatement Panels have an SAA rating of 1.04

The 1/3 octave ratings are:

125 - 0.27

250 - 0.87

500 - 1.17

1000 - 1.15

2000 - 0.96

4000 - 1.00

YouTube video:
https://www.youtube.com/watch?v=FsvTNTlkZdA

*******

Enjoy the sounds: https://soundcloud.com/barefootheart

Regards,

Andre

Having them that loose is a good idea. When stacked together with no air space between them they stop providing gains after the first layer. For future though it's not a good idea as you'll get better results with rock wool.

These are truly terrible panels at a humorous price. Don't buy these or any other 2" panels as they're sure to have such poor absorption specs. If you're buying panels you'll get a much better product & price from GIK Acoustics.

As I mentioned previously, 3.5" layer of Ultratouch gets you an absorption coefficient of 0.95 at 125hz. Perfect for any single layer (3.5") panel use.

nms, I'm not interested in them, but noticed they went with non-carcinogenic material. I think that's a good start. if I go for panels, I'll probably make them myself but may never share photos here...

Thanks for confirming about the space in between. I'm glad to hear that I may have done well with my strange design...

This looks like an effective wideband sound absorber–especially the 5.5" thickness variant, but I never knew fiberglass was carcinogenic.

Russell,

Yep, toxic stuff. Read some info here:

Fiberglass Insulation Dangers to Be Aware Of | DoItYourself.com

And:

Fiberglass - American Lung Association

So when you think how many hours you'll spend in your studio, breathing this stuff in, you want to be careful, plus the air movement by vents and fans - fiberglass wool is also dusty and airborne. My wife has chemical sensitivities, so we used UltraTouch for our whole house, attic and basement.

Good to know, thanks. I am currently waiting for a reply to a query made to the manufacturer of Ultra Touch denim insulation as to where I can buy it in Canada, or how to import it from the States. I'd like to get my hands on 5 16"x48" batts of the 5.5" stuff.

Russell, I got mine from Twin Maple in BC.

Also I see they also carry them in Ontario:
ECO Building Resource Ltd.
136 Wellington Street East
Aurora, ON
Phone: 877.741.3535
Website: http://www.eco-building.ca

You shouldn't be breathing it in at all. There's no reason for you to have exposed fiberglass anywhere in your studio and there are several ways to contain it. Fiberglass is perfectly fine to use as long as you handle it properly.

The formaldehyde in fiberglass used to be an issue, but they phased that out and you'll see everything is marked as formaldehyde free now.

People who are overly concerned have other choices though, such as rock wool or the knauf ecose products. I work with this stuff often and the only time I use a face mask or eye protection when handling rock wool is if installing overhead or using an electric cutter.

I've just bought a pair of the JBL LSR305s (they are my first 'quality' monitors) but they are not what I was expecting, so I was wondering if anyone could give me some advice with regard to the problem I'm experiencing.

Up until now I've been getting by with the Logitech Z4 (2:1) speakers, but now it's time to do the mixing, so bought the LSR305s. However, as soon as I started them up and ran some high quality (>192kbps) MP3s into them I found them they were really boomy. I then conducted a comparison, switching between the Logitechs and JBLs. I find that the JBLs produce much less highs than the Logitechs, despite having the HF trim switch at +2dB. The JBLs bass (set at 0dB) is thumping and fatiguing to the ears compared to the smoother bass of the Logitechs. The JBLs sound boxy, whereas the Logitechs sound more airy, open, detailed, fuller, and musically balanced. The only positive thing I'm finding with the JBLs is that they produce a slightly better stereo image.

If I had done a blind test I would have judged these JBLs to have been cheap downmarket speakers aimed at hip-hoppers!

I'm now putting a load of pink noise into them, but in the meantime does anyone have any advice?

Sell them and pick up some KRK VXT6. You'll get exactly what you're after.

You're still going to need room treatment if you want them to sound great though.

Case in point, a client whose room I'm about to start on just upgraded from KRK VXT8 to an $11k pair of Barefoots. No room treatment though, so he's been disappointed with the sound and said they don't sound much different to his KRKs!

Acoustic treatment is essential. I never liked or recommended those JBLs though.

If I'm unhappy I can at least send the JBLs back, as I paid a little extra for a 90-day money back guarantee. It's so damn ridiculous, because I'd spent ages scouring various forums to find the best value speakers, and everyone has been raving about the JBLs, yet I find they are inferior to a mere set of Logitech computer speakers that cost 15% of the JBL price! Surely they are not all half-deaf old men and liars?

Studio monitors are supposed to be accurate, yet these JBLs would indicate that the likes of Colin Blunstone, The Beatles, The Eagles, The Beach Boys, Charlie Rich and Glenn Campbell (those are what I've been playing through them) have been produced by inadequate idiots, which I know they have not. The JBLs are even failing to decently reproduce hi-hats and vocal esses!

The KRK VXT6 is a hefty price leap. Surely I don't have to pay so much extra just for a bit of full range quality that I've heard in much cheaper products, including my very old (passive) Wharfedales? At this rate it seems to me that I'd be better off just sticking with the Logitechs!

You're the saying the LSR305' sound worse than a 2.1 Logitech system that has equivalent RMS (for the entire system) to one driver in one unit of the JBL's? The logitech's produce better highs, better bass and are less fatiguing than the JBL's?

This logitech set?:

http://www.amazon.com/Logitech-Speak.../dp/B000AM6QHE

Am I reading this right? Forgive me I sound overly skeptical. It just that this sounds positively ridiculous. What do you have the JBL' hooked up to (dac, onboard, soundcard, etc.)

That's right, the pair of LSR305s I have here sound worse than the Logitech Z4 that you have correctly linked to. That's not to say that the Logitechs sound in any way bad; as far as computer speakers go they are very good.

I might have assumed one of the JBL monitors to perhaps be faulty, but both are behaving identically. I sit here listening to some high quality MP3s and I find that the JBLs are failing to properly reproduce highs, most notably hi-hats and vocal esses, while the lows sound hard and thuggish. These speakers sound cheap and nasty, like they were designed for hip-hop and similar. I switch over to the Logitechs and suddenly everything sounds much sweeter and more pleasant to listen to, with clearer, more pronounced highs and smoother lows.

To answer your question, I'm feeding the speakers directly (via a passive speaker switch) from the output of an M-Audio Audiophile 2496 internal pci sound card.