BYRTT's last post and picture shows measurements at different distance. The difference in reflections that we see is kind of an measrurement artifact. The question is about relative spl difference between straight signal spl and reflections spl. Secondly, mic position gets changed and that contributes a little too.
Those same reflections do exist in every measurement, but don't show up in same way! (SPL difference)
Kind of similar thing happens when we use different gating and measurement algorithm. With short gate the system just does not pick those reflections. (Time gating difference)
Different postitioning of speaker or drivers in a box has minor effect. Loudspeaker performance gets deteriorated if we optimize performance only for just one speaker and microphone location!
Those same reflections do exist in every measurement, but don't show up in same way! (SPL difference)
Kind of similar thing happens when we use different gating and measurement algorithm. With short gate the system just does not pick those reflections. (Time gating difference)
Different postitioning of speaker or drivers in a box has minor effect. Loudspeaker performance gets deteriorated if we optimize performance only for just one speaker and microphone location!
So the current measured response is fairly flat within what can be done inside a room as mentioned in above posts. Off-axis measurements also look good. Distortion measurements show uniform level about 60db lower.
The speakers do sound very good.
But i do sense something lacking in the mid tweeter integration. I recently setup an Lxmini for a friend and with just a two driver system, that speaker sounds spectacular.
my wife and I agree that the mid/tweeter integration of the DSP RC4 is falling short of the what the Lxmini is able to do.
Lxmini has a 700Hz LR2 XO between the 6"woofer and the 4" full range. Upper frequency extension is probably lacking, but i cant hear much of that anyway. But the cricual mid range frequencies are done very nicely.
I have to say the 2Khz LR4 between the W15CY and T25CF001 is still quite on the edge for both drivers and i do hear the tweeter straining on some tracks at loud volume.
The W15 as clear and pure as it is on slow clean tracks, isnt as effortless and smooth on complex busy music.
Fully satisfied with the RC4-DSP, but the learning must continue. Comments please.
The speakers do sound very good.
But i do sense something lacking in the mid tweeter integration. I recently setup an Lxmini for a friend and with just a two driver system, that speaker sounds spectacular.
my wife and I agree that the mid/tweeter integration of the DSP RC4 is falling short of the what the Lxmini is able to do.
Lxmini has a 700Hz LR2 XO between the 6"woofer and the 4" full range. Upper frequency extension is probably lacking, but i cant hear much of that anyway. But the cricual mid range frequencies are done very nicely.
I have to say the 2Khz LR4 between the W15CY and T25CF001 is still quite on the edge for both drivers and i do hear the tweeter straining on some tracks at loud volume.
The W15 as clear and pure as it is on slow clean tracks, isnt as effortless and smooth on complex busy music.
Fully satisfied with the RC4-DSP, but the learning must continue. Comments please.
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So here is an observation i have on certain music. There is a visual analyzer in Jriver's DSP stack.
On complex tracks i see a wider spectrum playing simultaneously and the spectrum itself changing rapidly with time. Versus on nice sounding tracks, the part of the spectrum playing at any time is narrower and the transitions in the music spectrum is slower and smoother.
Now, just trying to understand, what impact does this have on the drivers and how they sound? Are they able to rapidly dissipate energy and able to transition and play different parts of the spectrum?
Again these could be silly questions, but i have wondered.
On complex tracks i see a wider spectrum playing simultaneously and the spectrum itself changing rapidly with time. Versus on nice sounding tracks, the part of the spectrum playing at any time is narrower and the transitions in the music spectrum is slower and smoother.
Now, just trying to understand, what impact does this have on the drivers and how they sound? Are they able to rapidly dissipate energy and able to transition and play different parts of the spectrum?
Again these could be silly questions, but i have wondered.
back to the mid-tweeter discussion:
I have wondered what the potential impact on sound would be under the following what-if scenarios. Again, not planning on spending anymore on DSP-RC4 🙂. Just more learning for my next project, whenever that materializes.
1. A 6" paper/poly mid/midwoofer (like SB satori) from 200Hz to 1.5KHz coupled with a waveguide loaded larger tweeter like the T35C002. I Understand that the upper extension will be poorer, but i might not miss that.
2. A 5" paper/poly mid/midwoofer from 400Hz-3KHz coupled with the current T25CF001 tweeter. I understand that at 400Hz, CTC distance from the lower woofer might become important.
I have wondered what the potential impact on sound would be under the following what-if scenarios. Again, not planning on spending anymore on DSP-RC4 🙂. Just more learning for my next project, whenever that materializes.
1. A 6" paper/poly mid/midwoofer (like SB satori) from 200Hz to 1.5KHz coupled with a waveguide loaded larger tweeter like the T35C002. I Understand that the upper extension will be poorer, but i might not miss that.
2. A 5" paper/poly mid/midwoofer from 400Hz-3KHz coupled with the current T25CF001 tweeter. I understand that at 400Hz, CTC distance from the lower woofer might become important.
You have got a notch on the +20dB resonance? Two octaves down at -48dB plus 20dB is -28dB which is going to be audible.
The lxmini has a different sound radiation pattern to your speakers and so is going to sound different. Very broadly it should be increasing a sense of space with the increased reflections but at the expense of the precision of the stereo imaging. That it isn't to say your observations about the crossover integration don't hold but confidently separating it from the probably stronger difference in radiation pattern won't be easy.
I do have a notch to suppress the W15's breakup. Not one for the W22 though, it is LP at 300Hz LR4 so the 5KHz resonance is probably already buried.
I do agree on the sense of space created by the Lxmini, but the stereo imaging is pretty good.
the DSP-RC4 also presents a very clean and precise stereo image, though on rapidly panning stereo in a sound track, the speakers briefly become visible. But i do have to consider that they dont have a very symmetric placement wrt the room walls.
I do agree on the sense of space created by the Lxmini, but the stereo imaging is pretty good.
the DSP-RC4 also presents a very clean and precise stereo image, though on rapidly panning stereo in a sound track, the speakers briefly become visible. But i do have to consider that they dont have a very symmetric placement wrt the room walls.
The room has a strong influence on the sound particularly at low frequencies and so without things like multiple subs, room treatment and supporting filters to bring it under control one should probably be wary of pointing the finger too strongly at the main speakers. Nonetheless if there is a tweeter/midrange integration issue it is the sort of thing one might expect to hear through the room.
If the issue you are hearing is related to the 2 kHz 4th order LRR crossover between the midrange and tweeter then modifications to the crossover should change what you are picking up on. For the better or worse is less important than that it should change because this will confirm the source.
2000Hz XO point i would try up from LR4 to LR8 and let listening test rule which is best especially because you have FIR power to correct for the more phase turn distortion going steeper slope, reason is at 2000Hz its impossible get inside 1/4 wave ctc distance so at/inside XO region there will be a off axis error difference to a LXmini where yours will be more design axis dependent and therefor think lets get over this error and X more steep. I could be wrong so make your own mind to not steal your time but same tweak worked good for me in a 2-wayer and it maybe also help a bit for HF distortion profile.
XDir for vertical simulation is free and available at Tolvan data.
XDir for vertical simulation is free and available at Tolvan data.
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BYRTT, thanks for introducing xdir.
I have tried LR8 2K, LR4 2K and LR4 2.2K before. I think the later two voice subjetctively better. But i will try LR8 again with measurements to watch out for other anomalies
to meet the 1/4 wavelength CTC requirement around M/T, Coax appears to be the only option. I know 5E is a big fan of Coax and has developed some nice projects.
I want to try a coax at some point.
Yet, i feel a 4Way is something i want to explore.
in Linkwitz's Lx521 the 3"upper mid crosses over to the tweeter around 7.5K, ctc is hard to meet.
I want to try a coax at some point.
Yet, i feel a 4Way is something i want to explore.
in Linkwitz's Lx521 the 3"upper mid crosses over to the tweeter around 7.5K, ctc is hard to meet.
You right up there in frq Coax is one solution to vertical problem, i'm also crazy about Coax mod 5E did to his FST mid and expect he can sit or standup without much notice to change into frq area mid and tweeter control. A way to explore a better quality Coax driver was maybe to get a pair of KEF LS50 with driver in ones prefered naughty color and use driver for a home build exercise.
4 way is great and also lx521 at 7.5kHz works on design axis, horizontal should be fine think its mostly sit and standup plus power response that gets limit in XO region outside design axis and really nice these modern age we can control also in time domain with DSP.
Ctc distance is one of the reason myself do in full rangers as mid-tweeter, Vifa TC9FD, SS 10F/8424 and SBA SB65WBAC25-4 is great sounding drivers. Post 358 graphs is 10F and 10 inch woofer LR8 355Hz ctc 240mm, have since lifted HF extension little bit by freeze JRiver computer to run always at 192kHz (ASUS Essence STX II 7.1) so its possible do EQ in 20-50kHz area and have DACs stretch their legs. Drawback freeze it into DSP all from intput downstream to output for DACs at 192kHz is its not good as player anymore when files are lover rates as CD's are missing some natural DAC filtering. So now use another computer where second allowed JRiver license play files with native sample rate so DAC's digital/analog filters is present. Feel more comfort now as time go to control JRiver and Rephase so next exercise to learn is pair a 5 inch 5FE120 and 15 inch woofer to that 10F mid tweeter, should be possible get all three inside 1/4 wave even 1 octave above real XO point and is curious to hear such coherent data on paper in reality.
4 way is great and also lx521 at 7.5kHz works on design axis, horizontal should be fine think its mostly sit and standup plus power response that gets limit in XO region outside design axis and really nice these modern age we can control also in time domain with DSP.
Ctc distance is one of the reason myself do in full rangers as mid-tweeter, Vifa TC9FD, SS 10F/8424 and SBA SB65WBAC25-4 is great sounding drivers. Post 358 graphs is 10F and 10 inch woofer LR8 355Hz ctc 240mm, have since lifted HF extension little bit by freeze JRiver computer to run always at 192kHz (ASUS Essence STX II 7.1) so its possible do EQ in 20-50kHz area and have DACs stretch their legs. Drawback freeze it into DSP all from intput downstream to output for DACs at 192kHz is its not good as player anymore when files are lover rates as CD's are missing some natural DAC filtering. So now use another computer where second allowed JRiver license play files with native sample rate so DAC's digital/analog filters is present. Feel more comfort now as time go to control JRiver and Rephase so next exercise to learn is pair a 5 inch 5FE120 and 15 inch woofer to that 10F mid tweeter, should be possible get all three inside 1/4 wave even 1 octave above real XO point and is curious to hear such coherent data on paper in reality.
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interesting set of drivers BYRTT. Will keep those in mind.
Btw, are there any good small coaxials? 3"-4"+5/8" tweeter etc?
Would they work well in a 4-way as upper midrange+tweeter?
Btw, are there any good small coaxials? 3"-4"+5/8" tweeter etc?
Would they work well in a 4-way as upper midrange+tweeter?
Have not stumbled over small size high end coxials therfor i mention use LS50 either in original enclosure or take out driver itself for own build.
Funny enough regarding coax yesterday did read review at Troels Gravesen website where he visit Munich High End show 2016 and below quote relate to coax. To see picture from Munich go to "Recent up-dates" and schroll down to that TAD picture DIY-Loudspeakers.
Another way get good ctc seems a Synergy build by onni, where he use a real tweeter into apex, cost that SS tweeter is in same area your SEAS one http://www.diyaudio.com/forums/mult...ithout-compression-driver-17.html#post4701166.
Funny enough regarding coax yesterday did read review at Troels Gravesen website where he visit Munich High End show 2016 and below quote relate to coax. To see picture from Munich go to "Recent up-dates" and schroll down to that TAD picture DIY-Loudspeakers.
Another way get good ctc seems a Synergy build by onni, where he use a real tweeter into apex, cost that SS tweeter is in same area your SEAS one http://www.diyaudio.com/forums/mult...ithout-compression-driver-17.html#post4701166.
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Good arguments regarding LS50 coax being a mid-woofer and thanks those nice links.
Nice articles. These seem like excellent drivers.
Looks like they are difficult to get ahold of.
Yes looks like we need to get hands on hole speaker and cannibalize the golden part, but it looks nice data R300 is listed at -6dB up to 45kHz and -3dB at 28kHz.
R300 looks a mid/tweeter Hi-Fi Speakers - R Series - Fact Sheets - Bookshelf - R300 - KEF International.
R100 is mayby same as LS50 Hi-Fi Speakers - R Series - Fact Sheets - Bookshelf - R100 - KEF International.
LS50 have cone available in 3x colors Flagship Hi-Fi Speakers - LS50 - Overview - KEF International.
They are in the middle of the KEF range and priced around of £150 each. The Q series is cheaper but are a midwoofer+tweeter with less sophisticated motors. The Reference range driver is a similar sized midrange+tweeter with a better motor, neo magnet on the midrange I think, and slightly different looking cone but I don't know the price.
KEF no longer sell to the DIY market and a few years ago started clamping down in the US on selling new replacement drivers to people that don't possess the corresponding full KEF speakers. Nonetheless there seem to be a few ebay adverts and the chap in my first link was selling a pair on techtalk recently. They are probably obtainable if keen.
KEF also seem to have a line of build-in drivers, for wall/ceiling mount. Suspect they might be expensive for what they are, but should be available....
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