Have tought about making great speakers side to side to my tv, without taking lots of space.
I like challenges.
And when i saw a sell-out at TLPH in France, i order 20 Peerlees 5,9 inch FSL0512r01-08 for 9 Euro each.
Thinking of use 4 for "woofers" per side from 90-100 hz up to 1200- 1800 hz, and let 4 work up to 3K.
The 4 "woofers"in 6,7 liter ported and the other 4 closed.
Have 15 inch woofers up to 100-240 hz if i want.
A Viawave SRT-7 from 3-3,5K.
Here a paint-drawing and xover.
best regard John
I like challenges.
And when i saw a sell-out at TLPH in France, i order 20 Peerlees 5,9 inch FSL0512r01-08 for 9 Euro each.
Thinking of use 4 for "woofers" per side from 90-100 hz up to 1200- 1800 hz, and let 4 work up to 3K.
The 4 "woofers"in 6,7 liter ported and the other 4 closed.
Have 15 inch woofers up to 100-240 hz if i want.
A Viawave SRT-7 from 3-3,5K.
Here a paint-drawing and xover.
best regard John
Attachments
Hi!
I've tried things similar to this before, and some things I recognized immediately were:
1. Try to match the x-over output of the four "mid-bass" drivers to at least the same output as the "mids" below 2-300Hz. This is where the mids actually need support, and gain the most from being relieved from excursion. Lowers mid distortion, output capability and IMD quite significantly.
2. Try to adjust the bass x-over so that you're at least 10dB down compared to the mids at 800-1000Hz, otherwise the column will beam like crazy - but just in the midrange 600Hz-1.5kHz. This doesn't HAVE to be a problem if the set is finetuned in position, in the current room, at the current listening position - but if you ever want to move them to another room/house you're in trouble 🙂
3. If you make the bass-mid x-over according points 1 and 2, you can move one bass driver below the mids and get (from the top) B-M-M-T-M-M-B-B-B without impacting vertical lobing noticeably. If you need the tweeter to be placed even higher (2/3 up of the TV height works best for me in a home cinema front....) you could also try B-M-T-M-M-M-B-B-B
JBL-Pro have some really interesting white-papers regarding their small PA-column speakers ("CBT") that I think are still available on the JBL-Pro site.
Looks like a cool project 🙂 Certainly worth spending a bit of time optimiing!
I've tried things similar to this before, and some things I recognized immediately were:
1. Try to match the x-over output of the four "mid-bass" drivers to at least the same output as the "mids" below 2-300Hz. This is where the mids actually need support, and gain the most from being relieved from excursion. Lowers mid distortion, output capability and IMD quite significantly.
2. Try to adjust the bass x-over so that you're at least 10dB down compared to the mids at 800-1000Hz, otherwise the column will beam like crazy - but just in the midrange 600Hz-1.5kHz. This doesn't HAVE to be a problem if the set is finetuned in position, in the current room, at the current listening position - but if you ever want to move them to another room/house you're in trouble 🙂
3. If you make the bass-mid x-over according points 1 and 2, you can move one bass driver below the mids and get (from the top) B-M-M-T-M-M-B-B-B without impacting vertical lobing noticeably. If you need the tweeter to be placed even higher (2/3 up of the TV height works best for me in a home cinema front....) you could also try B-M-T-M-M-M-B-B-B
JBL-Pro have some really interesting white-papers regarding their small PA-column speakers ("CBT") that I think are still available on the JBL-Pro site.
Looks like a cool project 🙂 Certainly worth spending a bit of time optimiing!
Ditch the Viawave ribbon for sure………the vertical axis is too narrow for your intended use
Use a dome instead….somethinng small yet capable to reduce lobing. Scanspeak D3004 and slightly offset in the line. You have the flexibility of swapping L and R to suit your room and taste…..tweeters in or tweeters out.
I would only have the two center midwoofers playing down to 400hz or so and roll the others off
Use a dome instead….somethinng small yet capable to reduce lobing. Scanspeak D3004 and slightly offset in the line. You have the flexibility of swapping L and R to suit your room and taste…..tweeters in or tweeters out.
I would only have the two center midwoofers playing down to 400hz or so and roll the others off
Thanks for your input theSwede!
Will look in to it more 👍
My idea/plan with all this, was to also create some form of "pointsourse" from my "linesorce, to get "higher quality" when listening on music in stereo.
Thats why i have the middle 4 working up to 3-3,5K, so some form of pointsourse is created.
Regards John
Thanks for input 👍
Hmmmm
I had the Viawave since 2019/2020 and havent used it get, and it have high sensivity that suits my application. (96-98 dB from 3K)
Total sensivity on one speaker will be around 102 dB
https://hificompass.com/en/reviews/viawave-srt-7-ribbon-tweeter
Is your opinion based on stereolistening or cinemawatching?
Had a look of 4-5 different domes and all of them seems to have "bad" vertical axis.
When i sitt in my sofa the ears high doesen´t different so much, a maximum of 20 cm worse case.
Will look at Scanspeak D3004!
I also have a pair of Audax "gold" TW025A28 in waveguides, and a pair of Scan speak R2904/70000 and from the "sell-out" 10 Peerlees OT19NC00-04 and 10 Peerlees BC25SC55-04 (was previously in my planning going to use 3-5 of these small tweeters)
https://en.toutlehautparleur.com/media/catalog/product/datasheet/peerless/OT19NC00-04.pdf
https://en.toutlehautparleur.com/media/catalog/product/datasheet/peerless/BC25SC55-04.pdfRegards John
The Keele CBT's introduces several new and very different principles/layouts on top of the JBL straight line CBT's. I think it's good to let people go with the drivers and starting plans they envisioned, unless they're physically impossible or a straight up bad idea 🙂
My suggestion about moving the tweeter/mid section "up" one step among the "bass" drivers was just to match the physical layout around the TV better. If you can hang the speakers on the wall, AND have the center of them (considering the BBMMTMMBB symmetrical layout) at the right height then by all means do that, it's theoretically "better".
I see nothing wrong with the limited vertical dispersion of the viawave tweeter, I actually think the vertical dispersion in the 1-3kHz range will be even more narrow than that of the tweeter, considering the ~400mm minimum distance between the outmost mid drivers.
In my experience, narrow dispersion speakers when done well do more and more approach the sound of a very good pair of headphones. If you make the beam characteristics more narrow, you lower the amount of room reflections your brain "adds in" to the direct sound. That's not necessarily GOOD, it's just a different sound. I like it but it's definitely not for everyone. Having narrow vertical dispersion makes the soundstage smaller vertically, but keeps the side wall reflections to get more width and depth to the listening impression (IMO of course).
My suggestion about moving the tweeter/mid section "up" one step among the "bass" drivers was just to match the physical layout around the TV better. If you can hang the speakers on the wall, AND have the center of them (considering the BBMMTMMBB symmetrical layout) at the right height then by all means do that, it's theoretically "better".
I see nothing wrong with the limited vertical dispersion of the viawave tweeter, I actually think the vertical dispersion in the 1-3kHz range will be even more narrow than that of the tweeter, considering the ~400mm minimum distance between the outmost mid drivers.
In my experience, narrow dispersion speakers when done well do more and more approach the sound of a very good pair of headphones. If you make the beam characteristics more narrow, you lower the amount of room reflections your brain "adds in" to the direct sound. That's not necessarily GOOD, it's just a different sound. I like it but it's definitely not for everyone. Having narrow vertical dispersion makes the soundstage smaller vertically, but keeps the side wall reflections to get more width and depth to the listening impression (IMO of course).
A round transducer doesn’t have any axis……its response is 360 degrees on the reference plane…….only the baffle can offset that.
If you look at the graphs I posted, you’ll see that at your intended listening position, the content of the Viawave will be beaming at around a vertical window of twice its physical size. For music that would be fine, but for HT with a phantom center , dialogue intelligence will suffer greatly.
Yeah, cinema sound dialog is focused at 2/3 screen height, so easiest to draw to scale a side view of your theater to find the necessary vertical polar response.
http://web.archive.org/web/20180226...ads/2013/03/Ideal-Distances-Chart1.jpg?x37803
http://web.archive.org/web/20181007....homestead.com/viewingdistancecalculator.html
http://web.archive.org/web/20111204223229/http://myhometheater.homestead.com/verticalviewing.html
http://web.archive.org/web/20180226...ads/2013/03/Ideal-Distances-Chart1.jpg?x37803
http://web.archive.org/web/20181007....homestead.com/viewingdistancecalculator.html
http://web.archive.org/web/20111204223229/http://myhometheater.homestead.com/verticalviewing.html
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I was more meaning of axis in general, and HiFicompas was impressted also of the vertical of the SRT-7.
His words was also: 😉
One of the best world recognized ribbon tweeter - RAAl 70-20XR, having a membrane area even 2 times larger - 14cm2 and famous for its ability to work down to the frequency of 1.8 kHz, there's nothing to do here. It just should pass the crown of the best ribbon tweeter in the world to SRT-7.
And i don´t use a phantom center (and never has), but in that case i really se your point 👍
Will do.
Regards John
Look…..you don’t have to sell me on ribbon tweeters…..when used correctly, nothing beats a ribbon on resolution….but there are significant limits to their use. Crossed as high as they often need be, an MTM config is going to diminish their performance value……nothing to discuss or argue here……a well made dome is going to outperform in this use case.
But top off a three way comprised of a 2-4” cone or dome midrange and you’ve got a world class system. It’s your design and of course your criteria. I would only imagine you posted here as to get accurate, valuable feedback……what you choose to do from here is up to you. Ribbons due to their linear impedance are easier to cross to a mid…..a good thing for those new to this.
But top off a three way comprised of a 2-4” cone or dome midrange and you’ve got a world class system. It’s your design and of course your criteria. I would only imagine you posted here as to get accurate, valuable feedback……what you choose to do from here is up to you. Ribbons due to their linear impedance are easier to cross to a mid…..a good thing for those new to this.
Your absolutly right mayhem13 👍
Accurate, valuable feedback is learning me things, and im greatful for that.
It´s so many different dome types on the market, and i can´t tell witch type that will work?
I mostly like textil domes, but also some titanium dome.
Will 2, 3, 4, 5 Peerlees BC25SC55-04 (damped fabric dome) or 2, 3, 4, 5 OT19NC00-04 (ring radiator) work ? both are small.
Considering that your midrange 800Hz to tweeter x-over will already beam vertically quite a lot, I wouldn't worry to much about the Viawave ribbon. Sometimes matching dirctivity is more important than to try to get each individual range as "perfect as possible" 🙂
What you could do to get more vertical radiation with the other tweeters is to use three of the BC25's. I'd try two electrically in parallel outside, in series with one center unit in a vertical array. That would give you a 6ohm load and 3dB of support compared to a single unit. The shading (having the outer units slightly down in power compared to the center) will improve vertical spread by quite a lot above ~5kHz.
The OT19's are hard to work with, with rising distortion below 3kHz. To match output capability with the rest of the system, I think you could do a Tekton-style array with five of them in a tall, narrow "X" layout, but that can get fiddly to x-o correctly (the outer four needs to be low-passed to make the system work).
The reasonable way to use an OT19 for this use-case would maybe be in a very small 2.5kHz capable waveguide like the DAS-BC88. But then you're opening a totally different can of worms 🙂
What you could do to get more vertical radiation with the other tweeters is to use three of the BC25's. I'd try two electrically in parallel outside, in series with one center unit in a vertical array. That would give you a 6ohm load and 3dB of support compared to a single unit. The shading (having the outer units slightly down in power compared to the center) will improve vertical spread by quite a lot above ~5kHz.
The OT19's are hard to work with, with rising distortion below 3kHz. To match output capability with the rest of the system, I think you could do a Tekton-style array with five of them in a tall, narrow "X" layout, but that can get fiddly to x-o correctly (the outer four needs to be low-passed to make the system work).
The reasonable way to use an OT19 for this use-case would maybe be in a very small 2.5kHz capable waveguide like the DAS-BC88. But then you're opening a totally different can of worms 🙂
I have never used "so tiny" drivers before, and was thinking about needed thickness of mdf.
Do you people know?
As light cabinette as possible is a good thing, but don´t if it compromisses the outcome.
Will build like the picture, maby just shift plasement for the tweeter.
Attachments
Slowly the project has begun.
Been and still is, realy sick with fever and with severe headache.
This front baffle you don´t want to fabricate more times than necessary.
9 perfectly lined routed holes and minimum of space.
Hasen´t desided 100% witch tweeter to use, and them all have different size.
Audax "gold" in a 127 x 170 mm waveguide, the Viawave SRT7 or SS 7000.
And also have 10 Peerlees OT19NC00-04 and 10 Peerlees BC25SC55-04, and maby i can also use 3 of them ?
It´s tight with the waveguide-solution.
best regards John
Been and still is, realy sick with fever and with severe headache.
This front baffle you don´t want to fabricate more times than necessary.
9 perfectly lined routed holes and minimum of space.
Hasen´t desided 100% witch tweeter to use, and them all have different size.
Audax "gold" in a 127 x 170 mm waveguide, the Viawave SRT7 or SS 7000.
And also have 10 Peerlees OT19NC00-04 and 10 Peerlees BC25SC55-04, and maby i can also use 3 of them ?
It´s tight with the waveguide-solution.
best regards John
Attachments
So projects continue & as you probably understand I have no woman in my house.
Do everything on the kitchen table, with dust all over the house....not perfect, but is what i have ( zero grades and rain in Sweden now)
Everything get more complicated because my kitchen table isen´t flat, so have to put newspaper as to align all.
I go for the Audax gold TW025A28-8 in waveguides 127 x 170 mm.
Superhard with all pieces and different degrees of angles, and MDF does not forgive even 0,1 mm.
Soon is one ready for a little testing, but havent deside if i will let all 4 ported woofers work in the same space, or i should separate them in 2 and 2? (they have ca 30 liters to work in = 7,8 liter each)
Idea´s?
The midranges are now also in the same space with the tweeter.
Anything bad about that?
Do everything on the kitchen table, with dust all over the house....not perfect, but is what i have ( zero grades and rain in Sweden now)
Everything get more complicated because my kitchen table isen´t flat, so have to put newspaper as to align all.
I go for the Audax gold TW025A28-8 in waveguides 127 x 170 mm.
Superhard with all pieces and different degrees of angles, and MDF does not forgive even 0,1 mm.
Soon is one ready for a little testing, but havent deside if i will let all 4 ported woofers work in the same space, or i should separate them in 2 and 2? (they have ca 30 liters to work in = 7,8 liter each)
Idea´s?
The midranges are now also in the same space with the tweeter.
Anything bad about that?
