It's a continuation of the last project i posted "Syn 9: a change in direction" https://www.diyaudio.com/community/threads/syn-9-a-change-in-direction.375161/
But that thread already has three different versions of Syn 9 in it to confuse things. So having made a further change to the last one, I decided to declutter by going to a version 10 thread.
To recap: latest uses two Faital 10PR300's, four B&C 4ndf34's and a BMS 4594he. Horn is 90x60; 36"x22". No secondary flares, and not going to get any.
The low port was pulled in 2" closer to the throat than in the last syn9 version....other wise it's the same.
Oh, same other than being painted Chrysler Blue......and i made a third one for LCR trifield experiments..... because i like em so much.
Mouth looks like this.
Speakers look like this.
Weather sucks, so here's an indoor 1m tuning, made by averaging two 0-30 degree horizontal sets, made at 0 and 10 degrees vertical.
0 to 20 shown, made at 10 deg V. Red, green, blue.
Xovers are at 120Hz, 300 Hz, 700 Hz, and 6300Hz. (no sub shown obviously.
I'll be moving the low xover down to 100-110Hz when i can do better tuning outdoors, and probably try running mids up to 900Hz.
Here's the raw measurements for each driver section, or rather the spatial averages as described above.
Shown with 1/3 smoothing for ease on picturing the amount of overlap available.
In prior syns, I crossed straight from the CD's high freq section (red) to low drivers (blue). As you can see, that was no problem (and it sounded awesome).
This guy has the added mids (green); and simply sounds more awesome. Amazing really .... the clarity continues to astound me...(and why I built a third for playing with LCR .)
One last thing that's a little different from typical MEH build....
The four 4ndf34 mids are not enclosed...they just sit on the outside of the horn, kinda open baffle style, like this
Anyway, tis what i've been up to. Now, i've starting playing with the center speaker using matrices like given by Elias http://elias.altervista.org/html/3_speaker_matrix.html
And trying to build a variable frequency Gerzon matrix http://decoy.iki.fi/dsound/ambisoni...for Multispeaker Stereo (TRIFIELD)_Gerzon.pdf
I'd like to start a LCR thread soon for more techniques. I read through the whole "fixing the phantom center thread" and other true LCR threads i could find....would love to learn more techniques folks have tried.
But that thread already has three different versions of Syn 9 in it to confuse things. So having made a further change to the last one, I decided to declutter by going to a version 10 thread.
To recap: latest uses two Faital 10PR300's, four B&C 4ndf34's and a BMS 4594he. Horn is 90x60; 36"x22". No secondary flares, and not going to get any.
The low port was pulled in 2" closer to the throat than in the last syn9 version....other wise it's the same.
Oh, same other than being painted Chrysler Blue......and i made a third one for LCR trifield experiments..... because i like em so much.
Mouth looks like this.
Speakers look like this.
Weather sucks, so here's an indoor 1m tuning, made by averaging two 0-30 degree horizontal sets, made at 0 and 10 degrees vertical.
0 to 20 shown, made at 10 deg V. Red, green, blue.
Xovers are at 120Hz, 300 Hz, 700 Hz, and 6300Hz. (no sub shown obviously.
I'll be moving the low xover down to 100-110Hz when i can do better tuning outdoors, and probably try running mids up to 900Hz.
Here's the raw measurements for each driver section, or rather the spatial averages as described above.
Shown with 1/3 smoothing for ease on picturing the amount of overlap available.
In prior syns, I crossed straight from the CD's high freq section (red) to low drivers (blue). As you can see, that was no problem (and it sounded awesome).
This guy has the added mids (green); and simply sounds more awesome. Amazing really .... the clarity continues to astound me...(and why I built a third for playing with LCR .)
One last thing that's a little different from typical MEH build....
The four 4ndf34 mids are not enclosed...they just sit on the outside of the horn, kinda open baffle style, like this
Anyway, tis what i've been up to. Now, i've starting playing with the center speaker using matrices like given by Elias http://elias.altervista.org/html/3_speaker_matrix.html
And trying to build a variable frequency Gerzon matrix http://decoy.iki.fi/dsound/ambisoni...for Multispeaker Stereo (TRIFIELD)_Gerzon.pdf
I'd like to start a LCR thread soon for more techniques. I read through the whole "fixing the phantom center thread" and other true LCR threads i could find....would love to learn more techniques folks have tried.
I haven't measured sensitivity on this 90x60 horn yet. Here's a chart for a similar overall mouth size 75x60 from the syn 9 thread https://www.diyaudio.com/community/threads/syn-9-a-change-in-direction.375161/page-8#post-6829003
It has both 2.83V and 1W numbers. The four 4ndf34's are 16 ohmers all in parallel.
I expect the 90x60 will have the same CD sensitivity and a little less mid and low.
I can say, using a 4-channel amp with all channels being the same ....
Gains settings are: Low +3dB, Mid -2dB, coax CD hf 0dB, coax CD vhf 0dB
It has both 2.83V and 1W numbers. The four 4ndf34's are 16 ohmers all in parallel.
I expect the 90x60 will have the same CD sensitivity and a little less mid and low.
I can say, using a 4-channel amp with all channels being the same ....
Gains settings are: Low +3dB, Mid -2dB, coax CD hf 0dB, coax CD vhf 0dB
Hi Mark,
It's good to see you're still marching forward on your projects, most of mine have ground to a halt this winter.
I've noticed you have changed from the 10fe200's to 10PR300's with this build.
Do you think there is much difference between them at home user levels ?
Reason I'm asking is I have a pair of 10fe200's to build a 3 way test box once the weather improves.
I'm going to (attempt) rear porting the woofers this build, have you considered trying that ?
Cheers,
Rob.
It's good to see you're still marching forward on your projects, most of mine have ground to a halt this winter
.I've noticed you have changed from the 10fe200's to 10PR300's with this build.
Do you think there is much difference between them at home user levels ?
Reason I'm asking is I have a pair of 10fe200's to build a 3 way test box once the weather improves.
I'm going to (attempt) rear porting the woofers this build, have you considered trying that ?
Cheers,
Rob.
Hi Rob,
I think the 10fe200's would work just fine for home levels. I took the version 9 prototype outdoors, the initial syn9 build that used them... and that box sounded beyond great, along with being powerful enough for outdoors.
I've often thought i should post a "sleeper syn thread" .......a syn that uses the 10fe200's, 4fe35's and the lowest cost CD that gets to 1000Hz, that a person likes. A killer, not so expensive, syn...
No secondary flares, 90x60, and not even all that large. Mine was 34"x20".
Oh, the 4 fe35's were unenclosed on it too...open baffle style.......even more simplification and ease of build.
A big reason i moved to 10pr300's was simply, i already had them
I think the 10fe200's would work just fine for home levels. I took the version 9 prototype outdoors, the initial syn9 build that used them... and that box sounded beyond great, along with being powerful enough for outdoors.
I've often thought i should post a "sleeper syn thread" .......a syn that uses the 10fe200's, 4fe35's and the lowest cost CD that gets to 1000Hz, that a person likes. A killer, not so expensive, syn...
No secondary flares, 90x60, and not even all that large. Mine was 34"x20".
Oh, the 4 fe35's were unenclosed on it too...open baffle style.......even more simplification and ease of build.
A big reason i moved to 10pr300's was simply, i already had them
I've made many comments about the subjective SQ gain from adding small mids, versus previous builds that used a CD to reach straight down to large low-mids, 10"s or 12"s, at around 500Hz or so.
Art in particular has had me thinking the SQ might be due to reduced IMD from the CD, by reducing its low end excursion, since xover frequency is higher with the small mids.
I had been trying measuring the IMD of the new Syn9/10s with the mids vs the older Syn8s without, but wasn't ever sure about apples-to-apples ,given their other differences (size, pattern, secondary flares, etc)
Then it hit me a few days ago, ..............the new Syn 10 can run fine either way.
As is, as a 4-way using the small mids, with xovers at 300Hz, 700 Hz and 6300Hz (coax CD) .
Or as a 3-way without the small mids, with xovers at 500Hz and 6300Hz, .
I mean, look at the raw sections posted earlier....why not try it?
So, I've made a few IMD tests running both ways, using REW's dual tone generator and RTA.
Lower tone F1 has been in the range ff 500-700Hz....the range i can choose to have either the CD or small mids cover (will go up to 900Hz) in future tests).
High tone F2 has been in the 1kHz to 4kHz range, thinking that would be in the CD's range, where and IMD might be most objectionable.
Here's a couple of examples that are very typical of whatever combinations i try in those ranges.
This one is F1 = 550Hz & F2 = 3333Hz.
Small mids 4-way on left; CD straight to low-mid on right.
The spike at about 6.7kHz is 2nd harmonic and the same on both.
IMD is clearly lower on right with CD at 700Hz, than on right when CD reaches down to 500Hz.
Here's another: F1 = 612Hz F2 = 2502Hz
I screwed up, and the 4-way on left is 5dB higher in SPL, (which is accurate).
So that gives an advantage to the 3-way on the right, which still looks worse. (5k spike is 2nd harmonic again)
I've been pulling F1 and F2 numbers from the air...no real rhyme or reason other than the logic already presented.
When F2 is close to 1000Hz, the IMD's aren't too different. But once F@ is above about 1.5kHz, the 4-way consistently looks better.
Is this the cause of the clearly greater clarity when using small mids? I dunno for sure...and that's for sure.
But it is at least an objective measurement that's showing some difference.......because mag, phase, impulse, and polars sure don't show any differnces.
If anyone has some suggestions for continued IMD testing, and/or deferent F1, F2, tri-tones etc etc,.....would love to hear them. thx!
Art in particular has had me thinking the SQ might be due to reduced IMD from the CD, by reducing its low end excursion, since xover frequency is higher with the small mids.
I had been trying measuring the IMD of the new Syn9/10s with the mids vs the older Syn8s without, but wasn't ever sure about apples-to-apples ,given their other differences (size, pattern, secondary flares, etc)
Then it hit me a few days ago, ..............the new Syn 10 can run fine either way.
As is, as a 4-way using the small mids, with xovers at 300Hz, 700 Hz and 6300Hz (coax CD) .
Or as a 3-way without the small mids, with xovers at 500Hz and 6300Hz, .
I mean, look at the raw sections posted earlier....why not try it?
So, I've made a few IMD tests running both ways, using REW's dual tone generator and RTA.
Lower tone F1 has been in the range ff 500-700Hz....the range i can choose to have either the CD or small mids cover (will go up to 900Hz) in future tests).
High tone F2 has been in the 1kHz to 4kHz range, thinking that would be in the CD's range, where and IMD might be most objectionable.
Here's a couple of examples that are very typical of whatever combinations i try in those ranges.
This one is F1 = 550Hz & F2 = 3333Hz.
Small mids 4-way on left; CD straight to low-mid on right.
The spike at about 6.7kHz is 2nd harmonic and the same on both.
IMD is clearly lower on right with CD at 700Hz, than on right when CD reaches down to 500Hz.
Here's another: F1 = 612Hz F2 = 2502Hz
I screwed up, and the 4-way on left is 5dB higher in SPL, (which is accurate).
So that gives an advantage to the 3-way on the right, which still looks worse. (5k spike is 2nd harmonic again)
I've been pulling F1 and F2 numbers from the air...no real rhyme or reason other than the logic already presented.
When F2 is close to 1000Hz, the IMD's aren't too different. But once F@ is above about 1.5kHz, the 4-way consistently looks better.
Is this the cause of the clearly greater clarity when using small mids? I dunno for sure...and that's for sure.
But it is at least an objective measurement that's showing some difference.......because mag, phase, impulse, and polars sure don't show any differnces.
If anyone has some suggestions for continued IMD testing, and/or deferent F1, F2, tri-tones etc etc,.....would love to hear them. thx!
The IMD sum and difference frequency components are clearly far higher in the compression driver when when playing the lower frequency (f1) and higher frequency (f2) than when the cone mid covers f1.I've made many comments about the subjective SQ gain from adding small mids, versus previous builds that used a CD to reach straight down to large low-mids, 10"s or 12"s, at around 500Hz or so.
Art in particular has had me thinking the SQ might be due to reduced IMD from the CD, by reducing its low end excursion, since xover frequency is higher with the small mids.
Here's another: F1 = 612Hz F2 = 2502Hz
I screwed up, and the 4-way on left is 5dB higher in SPL, (which is accurate).
So that gives an advantage to the 3-way on the right, which still looks worse. (5k spike is 2nd harmonic again)
View attachment 1031878
Is this the cause of the clearly greater clarity when using small mids? I dunno for sure...and that's for sure.
But it is at least an objective measurement that's showing some difference.......because mag, phase, impulse, and polars sure don't show any differnces.
If anyone has some suggestions for continued IMD testing, and/or deferent F1, F2, tri-tones etc etc,.....would love to hear them. thx!
Of course, “far higher” when the maximum THD/IMD is below -55, under 0.18% is a relative term
.The IMD lower difference frequency “d2L” (2502-612=1890Hz) is below the noise floor range with the cone mids playing f1(612Hz), but rises +12dB with -5dB less output level using the compression driver to cover f1.
The IMD “d2H” is higher than the second harmonic distortion of f2.
No second harmonic distortion from the 4” cones are visible above the noise floor, though at -35dB below peak gig level, wouldn’t expect any!
Though the above test confirms that raising the crossover reduces IMD in the mid compression driver, it does not directly compare IMD levels of the 4” cones used in the same frequency range.
Since both can cover the range of 500 to 900Hz, using two test tones both in that range would give a better idea of the “fuzz” each creates
.Nice work, hope to see what happens at hand-clap levels (125dB+ peaks)
Art
Thanks Art,Though the above test confirms that raising the crossover reduces IMD in the mid compression driver, it does not directly compare IMD levels of the 4” cones used in the same frequency range.
Since both can cover the range of 500 to 900Hz, using two test tones both in that range would give a better idea of the “fuzz” each creates
Nice work, hope to see what happens at hand-clap levels (125dB+ peaks)
Art
Yeah this was some really low level testing....
Like said, twas indoors.....i don't do any serious testing, especially at higher SPL, until outdoors.
I have to believe IMD comparisons are gonna show up stronger then.
It's interesting to be able to do this the same box.....(small mids vs not)
I'd expect the BMS mid will hit 100% IMD 10dB below the B&C 4", you will want that box pointed skyward, and keep those tests short!
Does the open back 4" cause any cardioid polar behavior?
Hi Mark
Thank you for your continued sharing of progress. Also very very interesting that you have started making these IMD-tests that Art had proposed. Nice to see the benefits of extra 4" mids!
I almost thought I should not ask a question not related to the IMD-thing to keep things clear, but decided to do it nevertheless. As my question is pretty straight forward to answer I hope.
Regards
Steffen
Thank you for your continued sharing of progress. Also very very interesting that you have started making these IMD-tests that Art had proposed. Nice to see the benefits of extra 4" mids!
I almost thought I should not ask a question not related to the IMD-thing to keep things clear, but decided to do it nevertheless. As my question is pretty straight forward to answer I hope.
What is the reason/explanation for doing that? Did you do that for all 3 SYN´s (left, center, right)? Is that somehow inspired by Danley products?
Regards
Steffen
Hi Mark100,
nice! I've seen Joseph Crowe doing IMD measurements lately and he has been using very many tones and gauge the resulting "noise floor" to evaluate performance. See for example this https://josephcrowe.com/blogs/news/distortion-and-sound-quality-what-is-reasonable and I think this video showed some settings how to do it in ARTA
If you have ARTA lisence it would be interesting to see what kind of difference there is with distortion test like that, IMD test on steroids? I think you have nice unique opportunity with syn10 to zone in what makes the audible difference with the small mids
nice! I've seen Joseph Crowe doing IMD measurements lately and he has been using very many tones and gauge the resulting "noise floor" to evaluate performance. See for example this https://josephcrowe.com/blogs/news/distortion-and-sound-quality-what-is-reasonable and I think this video showed some settings how to do it in ARTA
If you have ARTA lisence it would be interesting to see what kind of difference there is with distortion test like that, IMD test on steroids?
I think you have nice unique opportunity with syn10 to zone in what makes the audible difference with the small mids Hi Steffen,
after months of listening to syn9 v3, i felt the weakest link was the low driver section, the two 10pr300s. It had plenty of SPL and covers 100Hz to 300Hz fine, but i dunno...still sounded weak compared to all other sections.
So when i built the third syn9v3 for LCR, i made it where i could play with the low ports a little, in a way i could also retro fit whatever changes i might like into the existing pair of syns.
So i took a stab with moving the same 2.875" round port right under the center on the 10" cones, with the driver mounted in the same place as on syn9v3.
Had to keep driver mount location the same due to routed excursion recesses that can't be altered.
Anyway, that moved the port center from 11" to throat, to a closer 9" to throat.
I liked what i saw in terms of overall smoothness, as well as an upward bandwidth extension, which would give me more room to choose xover frequency to the small mids. It did come at a loss of about 2dB at 100Hz however.
here's the raw low response. Blue is syn10 at 9", black syn9 v3 at 11"
I'm a junkie on trying to get best acoustic response before processing, so i spent a morning to convert the syn9s to the new port location.
(And i already needed to remove all drivers to get that electric blue paint on haha.)
I know that's a long winded explanation, but i wanted to give it so there's no pretense i took anything from Danley...this is just me stomping around in the woods on my own, Follow at own risk Lol
Hi tmuikki, thanks for that link. I had forgotten it and will revisit to learn.
Yes, i've been using ARTA for two sine, to see how it compares with REW. So far, looks' all the same other than REW has clearer graphics.If you have ARTA lisence it would be interesting to see what kind of difference there is with distortion test like that, IMD test on steroids?
Here is my one and only mutli-band compare so far. 3-way on left; 4-way on right. I don't know what i'm looking at !!!
REW has a very robust looking multi-tone section in its Signal Generator....ready to explore that.
Wow yes, i think so too. Can't say i've heard of s speaker, where it can be used perfectly fine as either a 3 or 4 way,I think you have nice unique opportunity with syn10 to zone in what makes the audible difference with the small mids
Stumbled on this by accident when i moved the low port as just described to Steffen.
Hi Mark
I do appreciate your long explanation very much!
I am oscillating between two ways to build my MEH´s. One with your configuration with the low drivers on top and bottom and mid´s on the sides, and the other being with low´s and mid´s both on the top and bottom plates.
I have had this idea, to build the MEH in a way, that I could change the top- and bottom-plates only, without dismantling the whole horn, modul-style, making it easier to experiment! Hmm. But that is actually not that practical when using my existing 15" low-drivers (instead of four smaller 16 ohm lows). Hmm, again! I frequently end up, thinking your approach is actually the easiest to follow to get started, and then accept to have to build more versions as new ideas come to mind! I need a bigger house, to have all those versions stored!
But thanks again for your thorough explaining.
Steffen
I do appreciate your long explanation very much!
I am oscillating between two ways to build my MEH´s. One with your configuration with the low drivers on top and bottom and mid´s on the sides, and the other being with low´s and mid´s both on the top and bottom plates.
I have had this idea, to build the MEH in a way, that I could change the top- and bottom-plates only, without dismantling the whole horn, modul-style, making it easier to experiment! Hmm. But that is actually not that practical when using my existing 15" low-drivers (instead of four smaller 16 ohm lows). Hmm, again! I frequently end up, thinking your approach is actually the easiest to follow to get started, and then accept to have to build more versions as new ideas come to mind! I need a bigger house, to have all those versions stored!
But thanks again for your thorough explaining.
Steffen
For sure ! Must avoid ear damage, magic smoke, and neighbors with shot guns LOL
Sorry i missed this question.....
Nope, not all.
The second syn9 version had them enclosed. I can't really say for sure due to all the extra variables, but i believe the mids sound better open back.
Cool to see open backed mids! Have been considering the possibility of such a thing myself, with the thinking that it's one less variable to worry about, and should help with thermal dissipation if that's a concern. I suspect it may help with imaging and soundstage as well, less decay time in the critical midrange.
Mark,
"Nope not all", did you mean "not at all", as in the dipole arrangement has no effect on radiation pattern
?I don't recall you posting any polars of the Syn9 past 50 degree off axis.
To detect any difference in pattern, if there is any, would require measurement past the horn wall angle, preferably through 180 degrees.
Comparing the lower pattern between of the compression mid and open back 4" would be interesting.
Art
Mark,
"Nope not all", did you mean "not at all", as in the dipole arrangement has no effect on radiation pattern
Yep, meant 'not at all' ..... i flunked all my writing classes Lol
I dunno Art, I have trouble getting concerned with pattern outside the conical H&V angles.
Doesn't seem to matter for either indoor or outdoor listening...to my ears anyway.
I dunno......probably just me, but i think the community has gone overly obsessive on polars and CEA 2034.