I don't know how speakers were located, but lean bass is fully expected if small bass reflex speaker with rear port is located on stand at 70...120 cm from front wall. In addition, BSC of LS50 is quite irrelevant due to high humps at low treble. Evaluation of BSC is much easier and makes some sense e.g. with my Q100 which has smoother frequency response up to mid treble, and magnitude of front port signal does not depend so much on measurement distance.
This way Measuring Loudspeakers, Part Three Page 8 | Stereophile.com
He doesn't tell the exact location of the speaker though. In photographs we can see them in typical "hifi-location" almost 1m away from front wall, on a pole/stand. Avarage of 120 measurements with different standardized mic locations. Sometimes he publishes measurements at someone else's room.
This is the in-room response that Atkinson calls "typical"
Attachments
^120 measurement points won't help if speaker position is not compatible with mechanical construction and sound balancing. Results of different speakers could be comparable but still worthless for people who can hear and are able to make proper listening setup. I suppose decent and valuable speaker measurements must be done someone else than stereophile also in the future.
Anyway, this has nothing to do with coaxial drivers for diy. Sorry about OT.
Anyway, this has nothing to do with coaxial drivers for diy. Sorry about OT.
I am using 8 inch tannoys coax actives since almost 10 years now. I like what they do but technically i see two major issues with all coax's:
1) The tweeter assembly is tightly coupled to the bass/mid frame and when one knows the kind of microscopic displacements a tweeter does at high frequencies i would like to see a measurement of what goes fed trough the tweeter voice coil when driving just the bass? on my tannoys there is a large blob of some putty between tweeter rear plate and a cross brace maybe to try and mitigate this effect, not sure how effective that is. At least there's something.
2) Of course of having the waveguide/cone moving and modulating the highs will also be an issue, some mitigate this by using even "large" 12 inches only from 170 Hz or so upwards to reduce this- the smaller the cone, the greater the displacement
+ termination shape of bass suspension to basket is likely to be critical, just like termination of a horn/waveguide.
To me the next breakthrough in coaxials would be addressing point 1.
1) The tweeter assembly is tightly coupled to the bass/mid frame and when one knows the kind of microscopic displacements a tweeter does at high frequencies i would like to see a measurement of what goes fed trough the tweeter voice coil when driving just the bass? on my tannoys there is a large blob of some putty between tweeter rear plate and a cross brace maybe to try and mitigate this effect, not sure how effective that is. At least there's something.
2) Of course of having the waveguide/cone moving and modulating the highs will also be an issue, some mitigate this by using even "large" 12 inches only from 170 Hz or so upwards to reduce this- the smaller the cone, the greater the displacement
+ termination shape of bass suspension to basket is likely to be critical, just like termination of a horn/waveguide.
To me the next breakthrough in coaxials would be addressing point 1.
FYI Genelec has a series of monitors using a novel coax design: Minimum Diffraction Coaxial
These are probably not available for DIY.
These are probably not available for DIY.
I have a cheap tweaked KEF Q100. I could not dismantle the speaker so I did not change the wiring and, above all, I could not add viscoelastic (Tecsound SY-70, I am very satisfied with this material that I have used in several cases) to the walls. I have been thinking for a while about adding side panels, which should have rounded edges for better aesthetics.
[PDF, Spanish] Tecsound SY measurements at third page
What improvements do you propose to solve Q100 limitations?
By the way, these speaker measurements encouraged me to buy the speakers:
Kef Q100 Speaker Drive Unit Testing
Kef LS50 Drive Unit
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In the linked discussion it becomes obvious that KEF have both developed the mechanics and xo of UniQ still further again in Qx50 series. There are different cone materials and motors in different versions or series - LS, Q, R, Reference, Blade, Muon - and two sizes of cones, 130 and 165mm
Cenelec uses MDC coaxials only in 83series three-way speakers, to minimize the intermodulation issues. Minimum Diffraction Coaxial (MDC™) Driver Technology | Genelec.com
ps. I have happily listened to SEAS T18 coaxial 2-ways in my HT room for over 5 years now! Haku - Hifitalo[1].pdf
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As a tribute to Genelec i can attest that I've never found their two way with waveguide (1031A) wanting in soundstage compared to the 8" tannoy coaxes. Would love to hear their coaxes with waveguide.
They cross it highish 470 Hz. I really beleive that wathever the size of your coax make it 3 way, or at minimum 2.1 with H/pass on coax. On this forum there is a gentleman from UK using 12" tannoy x-over at somewhere 170/200 i can't remember his name right now
They cross it highish 470 Hz. I really beleive that wathever the size of your coax make it 3 way, or at minimum 2.1 with H/pass on coax. On this forum there is a gentleman from UK using 12" tannoy x-over at somewhere 170/200 i can't remember his name right now
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I've no plans to do anything, but I would make low pass steeper, add internal brace and add cubic foam block behind vent to damp pipe resonance.
The coaxial crown is fixed very strong in my boxes and I gave up trying to remove it for fear of damaging it.
Yesterday I came up with a brilliant idea, well, do something that I already did when I experimented first with very cheap speakers, in 2011. At the end I put Tecsound SY70 also on the outside. After putting sealer and two coats of acrylic black paint that material looks like leather.
[Spanish] HUM: mejoramiento con Tecsound SY 70 y fibra de vidrio de unas cajas de musica II | Nauscopio Scipiorum
Being careful and finishing it well the edges can be spectacular. Being black, photographs do not do justice. And cheap camara too.
I had reduced the bass-reflex diameter with paper (hidden thanks to the grid) -> more clean bass. After my cheap tweaks I have more bass than the originals -> I do not need a subwoofer with my musics (classical, baroque, jazz...).
Yesterday I came up with a brilliant idea, well, do something that I already did when I experimented first with very cheap speakers, in 2011. At the end I put Tecsound SY70 also on the outside. After putting sealer and two coats of acrylic black paint that material looks like leather.
[Spanish] HUM: mejoramiento con Tecsound SY 70 y fibra de vidrio de unas cajas de musica II | Nauscopio Scipiorum
Being careful and finishing it well the edges can be spectacular. Being black, photographs do not do justice. And cheap camara too.
I had reduced the bass-reflex diameter with paper (hidden thanks to the grid) -> more clean bass. After my cheap tweaks I have more bass than the originals -> I do not need a subwoofer with my musics (classical, baroque, jazz...).
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Monacor SP-308CX PA Coax Speaker 8" 300W.max
How do these drivers stand up to the issues mentioned previously? They look like very good vallue and the driver family (8, 10, 12") seem to have positive words peppered around the web.
How do these drivers stand up to the issues mentioned previously? They look like very good vallue and the driver family (8, 10, 12") seem to have positive words peppered around the web.
Days ago in others forums where I have a thread I post some links about coaxials after read this review (I was searching a coaxial with high sensitivity to the DIY class A 20 watts ALPHA).
Review: The Coherent Model 8 – A Speaker For (Real) Life | Wall of Sound | Audio and Music Reviews
Coherent Sound from Frank Fazzalari
https://www.klusster.com/portfolios/daniel-mances-portfolio/contents/546
[ The basic requirements were fulfilled by the American made Radian Co-axial drivers. However, this was only the the starting point. The Radian driver undergoes extensive modifications by Coherent Audio and is matched to a special crossover designed and built by Coherent. The crossover is based on totally new design principles and incorporates special coils which are also built by Coherent… ]
https://radianaudio.com/product-category/components/coaxial-loudspeakers/
-> Radian 5215B Coaxial Speaker
https://radianaudio.com/products/5215b/
[copyright material deleted]
Review: The Coherent Model 8 – A Speaker For (Real) Life | Wall of Sound | Audio and Music Reviews
Coherent Speakers from Canada | Audiogon Discussion Forum
Coherent Sound from Frank Fazzalari
https://www.klusster.com/portfolios/daniel-mances-portfolio/contents/546
[ The basic requirements were fulfilled by the American made Radian Co-axial drivers. However, this was only the the starting point. The Radian driver undergoes extensive modifications by Coherent Audio and is matched to a special crossover designed and built by Coherent. The crossover is based on totally new design principles and incorporates special coils which are also built by Coherent… ]
https://radianaudio.com/product-category/components/coaxial-loudspeakers/
-> Radian 5215B Coaxial Speaker
https://radianaudio.com/products/5215b/
[copyright material deleted]
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I think/suspect that coaxial > 5.25"/6.5" with very good off-axis response there should not be many. I am afraid there is only woofer + tweeter with logarithmic waveguide. Am I wrong?
If anyone knows of a high sensitivity alternative of the KEF Q100 coaxial speakers (DIY or not) I am all eyes.
If anyone knows of a high sensitivity alternative of the KEF Q100 coaxial speakers (DIY or not) I am all eyes.
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FaitalPRO | Coaxial Loudspeakers | 6HX150
Documented build here:Coaxial Speaker Build Thread with FaitalPro 6HX150
Documented build here:Coaxial Speaker Build Thread with FaitalPro 6HX150
What? There's a -2db relaxed dip from ca 1,3 to 2,2khz at -30 degrees. Granted there is a -6db dip at 1,3khz 45 degrees off axis, but for the most part it is much better than that.
Can you point to measurements of another comparable driver that does better? At 45 degrees off axis?
You would need to add a woofer but I am a fan of 3ways.
If you want lower and/or louder the only way is to go bigger.