Lii Audio 15" full range

:) I have fullrange speakers, or widebands as I like to call them ;) I like them, and they do have some advantages, I also like open baffle. Like you, I have no illusions when it comes to their limitations, but it is forever pros and cons, which is what makes it interesting to me and always best to stick to facts as much as possible.
 
When one add just 1 capacitor or 1 resistence or 1 inductor to the music signal this electric active part...

Capacitors, resistors and inductors are passive, not active, components.

...will lost the low level electric signal as heat,

Resistance does not selectively target low-level signals.

...this low level energy are the musical harmonics...

Not all of it. Some of it.

...and are time aligned with all the sound present in the recording,

Time alignment has nothing to do with resistance. It is a function of drive unit location and the relevant phase angles.

this low level musical energy will do the performance sound as real music,

I appreciate this is your opinion, but until you define what, precisely, you are referring to by 'real music', it only has meaning for yourself.

but once it is removed by the presence of a capacitor or resistence or inductor etc

As noted, capacitors, resistors and inductors do not selectively eliminate low-level signals while leaving those of higher level intact. That isn't how they work.

Sorry but this is the awfull thruth, there is no free lunch in Xovers vs FR drivers, however dont be surprised as flat earth minded engineers will prompt disagree.

Well, speaking as somebody who designs loudspeakers of both single-driver and multiway type, I can only gently point out that there is no free lunch in either approach. Take your own avatar for example. Every moving coil wideband drive unit without exception has a crossover. It just happens to be mechanical. That is not, unfortunately, any kind of guarantee of quality.

The device know as Notch Filter also has the same deleteric bad effect on the music they all are not recommended for use with a FR drivers

According to whom?
 
Maybe I should give the large Decware betsy a go, with it's "43% down from the top" to see what edge has to say about that? Thanks!
baffle 100cm is good with speaker at 60-70cm, you can tilt some ° btw

test with old wardrobe door ;) or modular baffle like this
 

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frugal-phile™
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With a tweeter and a xover all theharmonics and the musical presence will be lost.

Do you mean that because of the timing errors introduced by the XO that the harmonics are no longer contained within the envelope of the fundamental?

That does indeed happen (it can be minimized, but most do not consider it critical) with a circuit in front of the driver. A FR without a whizzer will usually do a better job of maintaining the harmonics within the envelope. If the source maintains this information it can allow for a greater insight into what is playing, who is singing, where they are. Some find this important, and is i believe one of the things that brings the FR “magic”.

This is a simplified example. A set of harmonics is separted out. If one was to collapse them vertically they “fit within the fundamental). A time delay at some frequencies will shift the harmonics within that band out of sync with the harmonic. I believe the musical term is that the timbre changes.

abhYU.png


dave
 
Hi 'jj',
Not sure what's producing that 3dB lift at the lower mids on the "edge program" but maybe this assumes some floor coupling perhaps - could you try it with some curved sides like a wine cask/keg - if the height is about 50", the sides will 'belly-out' about 9" to give an outside width about 30+", maybe 35"?

Wouldn't it be good to have a freq response above 700Hz as smooth as the diagram indicates!
 
I assume bass is maximum here and diminishes as you move the driver towards any edge

However to my eye, the resulting FR is "better".

Could someone please confirm that I'm using the program as intended?
However I never see that position - nor any other - in these common arrangements; always the "stock" placement.

"43% down from the top"

Hmm, max bass will be at the very bottom where it will get the full gain of mirror imaging, so obviously normally limited to a bass app, though tilted back like the Wharfdale it can be used over a wider BW.

Right, as you move off center the eigenmodes between the driver/baffle edge becomes increasingly random, smoothing out the frequency response.

Confirmed! :)

Did [can] you account for the baffle being angled back like the Wharfdale ? This changes the response. Regardless, there's numerous reasons why different designers/DIYers choose to not 'rock the boat' as consumers and 'significant others' can be pretty fickle about size/shape/'look'. That, or just didn't have the technical knowledge we're exposing you to.

Earlier, I posted "Vertically, at some odd harmonic, so normally at H*0.21, 0.349, 0.424." H*0.424 is the actual 43%. ;)

GM
 
Hi "jhj" - yeah I have the dimensions of the Decware keg, they are 42 X 32". I havent yet got the chance to model them in edge. Thinking about investing in a router. I want to be listening to them in the baffles soon. Hopefully the FR works out to be just like the simulator said ;')

GM - now I get it - the math expression. I dont think the edge accounts for a backward tilt. My SO is pretty good for allowing me to setup a couple of tombstones in the livingroom. She was like, what's wrong with the 6"? They sounded fine. Well, they did, but, you know - gotta play some. Hopefully it ends up pretty good!

I read a couple of papers by David Griesinger where I believe he said something like the relative time arrangement of a sounds harmonics in a 1 - 8 Khz band ... is a part of a sound's quality that holds our interest. This guy gets hired to fix seats in actual performance halls - fix them sound quality wise - and has commented that because of reverberations wrecking the relative harmonic phases, different seats in a hall can be the difference between falling asleep and being enlivened by a performance.

The particular frequency range led me to consider why all these two way systems with a FR handling the top end are so popular. Why some people prefer such beasts with large horns - like the Altec Valencia I once owned and its 800Hz crossover to the horn. Why some people prefer a speaker that performs way better in maintaining harmonic phase relationships than in the loudness of different frequencies. Why some people give up playing music so loud, to instead be able to bask in a different aspect of it. Or they have to, as loud doesnt do it like it used to. Gotta find something.

So one night I pushed the BIN button on a un-seeming pair of FE103s in Akai cabinets from someone who's handle was "300B". Listening right out of the shipping box I was immediately hooked. I believe I heard this phase coherency in the 1 - 8kHz range. I wanted to marry these speakers, they did "it" so well. What's "it"? Phase coherency in the 1 - 8kHz range. At 62, it's something I can still perceive - the 16Khz tinkling of the bell tree is long gone. Appreciating that, I thought "what if I try a Dayton 6" FR?" So nice to listen to after some EQ adjustment - just dont get overly concerned with those off axis FR plots...

Then I thought I want to own 15"s again - get that near field wrapping around the sofa. How long have I got before I'm forced by ageing to listen to anything I'm able to hear through someone's junk capacitor? (have to live in hell before I even get there?) So, having made a little extra cash on ebay, I splurged on these Lii Audio. Apparently, they do "it" too. No RLCs in some filter messing with the harmonic phases right in the middle of that 1 - 8k. The music is so interesting to listen to, I have to arrange an automatic switch to turn it off after an hour or two - or I'll sit there all day. How well you're engaged in a reproduced - or live - sound performance is certainly part of a overall measure of sound quality, it's just not so direct a process to get that onto some plot.
 
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Lii 15" Finally in OB

I finally got to it and put these F15s in the table top laminated MDF material I picked up. I did use "The Edge" to locate the speaker geometry on the OB and basically put them where I felt best after running through several candidate positions. I believe the hump shown in the response is audible and I've improved it some with EQ in the Daphile player I'm using.

See photos -

There were a few challenges, as I dont have the ideal tool set for creating these, but I designed some guides for cutting straight 30" lines and 14" circles, drilling at right angles, etc. I have a small drill press and table saw, but most of it was fabricated using free-hand tools. A 60 tooth circular saw blade made decent cuts with some occasional chipping of the laminate - I did miss the target location of one of the drivers; one's 1/8" closer to the baffle edge than the other.

The boards stand 41.5" tall and 30" wide. I kept the 30" diameter circle of the original table design, as I preferred not to disrupt the already applied edging. I made the front toes and back legs from the slice I took off to set the height. This is my "poor-boy" version of the Decware "ZF15L" for basically the cost of the Lii Audio F15 drivers plus some shop effort.

These things are big and I have a very nice wife to allow me to have them in the living room. I havent had any time to experiment with room placement, having just put them into form today. (If someone could suggest an approach to putting a protective grille over these drivers, I'd be happy to listen!)
 

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I have used pizza screens. They fit perfectly on my 15' Fane drivers. I spray painted them black and used rare earth magnets glued to the screens to hold them on the drivers steel basket. A 1mm thick rubber bumper on each magnet eliminated the buzzing I was getting from bass notes. About $5cad each at a restaurant supply store.
 
@scott - of course, it's the simulated - I wish. I've tried to boost the bottom using my player's EQ and they do sound better that way. No noticable IM from the extended bass on the treble, at my listening levels. The cones still barely move even so.

I bought a pair of the 18" 4 ohm Wharfdale drivers for $100 (shipped) which may or may not make it into this board. If they do, they'd be driven by another amplifier with the requisite rising response built in. Designing the filter to do that and hit where these start to drop may be easy, or a bit of a challenge. My wife has made it clear she doesnt like the infrasonic stuff.

I swapped 'em L-R today as my wife asked if they could be moved a little closer together. Gotta stick the Xmas tree somewhere...

@Jazzfan - I'm going to try your idea. These have cast frames so the magnets wont stick so simply. I bought a pair of 16" pizza screens for <$20 (shipped) off ebay. We'll see what I can come up with, even if it's remove for listening, replace for unattended protection. Great idea to paint them black - thanks!
 
Sorry for the total noob question but I am an electronics guy not a speaker guy (yet)! :cool:

My current speakers are modified Klipschorns. I have built several fullrange speakers in the past ... Fostex, Alpair 12p Pencils, Alpair 5 Frugel Horn Lites,etc. There is a clarity and imaging that fullrange speakers do that other speakers can't compare with. But, they don't dig deep enough for me to replace my behemoth corner horns.

The F15 looks promising but as stated in this thread, the Qts is a bit high for an enclosure. I used unibox to model the enclosure they have on their website but the F3 is only ~40Hz with only a 1.5db spike. I e-mailed them and asked if they had any measured data on that enclosure and they do not yet I see a lot of F15's in bass reflex cabinets on their website.

I was wondering if maybe a MLTL enclosure would be able to go a little deeper? Unfortunately the programs for those are unobtanium and/or over my head so I have not simulated that yet. Just wondering if the rules for MLTL and Qts were the same as bass reflex since they are very similar.

Also forgot to add that OB is out because my room is small at 12' x 14' and I listen across the 12' direction. That and lack of bass would not satisfy me. I also need high efficiency as I run a 45 SET.
 
I was wondering if maybe a MLTL enclosure would be able to go a little deeper?

Just wondering if the rules for MLTL and Qts were the same as bass reflex since they are very similar.

I also need high efficiency as I run a 45 SET.

Yes, though at the expense of lower power handling down low since one is always trading efficiency for BW.

For true MLTL, only vaguely, i.e. must lower tuning a measurable amount, which many designs don't, so merely a column/tower BR, which is still worthwhile when a small footprint and/or driver up at ear/whatever height is desired.

What's the amp's output impedance [Rs] since combined with wiring [add 0.5 ohm] it's likely going to jack the driver's effective Qts up to OB/IB or ~ aperiodic [extremely well damped/lower efficiency] alignment: Qts' = Qts + any added series resistance [Rs]: HiFi Loudspeaker Design

Guessing that the best 'box' alignment will be OB 'gapped' in the corners with tuning/damping empirically arrived at to 'taste'.

GM
 
There's perceptible bass (with EQ) using the Boards shown. It's not gut wrenching, but the bassist is there and I can definitely hear if not all the notes being played. I can live with it - others who'd demand a much more deeply toned response would not. The cones barely move, even with the EQ.

I agree with jmpsmash - the HF roll-off suits my ears, which roll off at the top also. In my case, adding a "super-tweeter" wouldnt help - I cant hear those frequencies.

I can, however, hear the "clarity and imaging" craigtone refers to. I believe it has something to do with relative phase preservation in the 1 - 8K range, but, whatever. All the FR speakers I've played with recently do this.

Just wanted to try the OB design, as it interacts with the room more like a dipole electrostatic and has no sound reflection from the cabinet back through the speaker cone issues. So far, so good.

I've no idea how many hours / at what power level break-in these F15s need to begin sounding "really good". If you tap the cone with your finger, it's as tight as a drum. If you do that to the cone of a 12 or 15" Velodyne sub, you can see the resonant frequency and exponential decay of the cone movement.

I think you cant have both in a single FR speaker. I'm suspect of these little 3-4" that go to 40 Hz in some cabinet - yeah, it can achieve that, but what's happening to all the higher frequencies being reproduced at the same time?

I think these Lii's were designed on purpose to not allow deep bass cone excursions to mess with the rest of the spectrum. That's a compromise that'll put off deep bass lovers hoping for a single driver solution.
 
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From your "edge response" it looks like the combination (driver + baffle) is rolling off quite well at about 6dB down at 80Hz - perfect for a subwoofer but it'll have to be a good one to avoid colouring the sound - maybe a 'pro-audio' one with a decent plate amp in a B2 chamber (infinite baffle)