SB 3 way

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colmo

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Joined 2015
#1
I would like to build a 3 way using SB drivers.
For WAF 10 inches wide with flat baffle so I can fit a grille.
Drivers SB23NRX 8 inch bass, 5 inch mid and 1 inch hf.
Has anyone built something similar who would kindly share the design and crossover details.
 
#3
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#5
If you are happy with a floorstander then there is also the Jeff Bagby/Javad Shadzi Ceramico’s that are detailed on the Facebook DIY Loudspeker pad. These use two SB23CAC in a 2cuft sealed box (10.5” wide baffle), SB15CAC for mid range duties and the SB26CDC tweeter. Iirc they went down pretty well when played at a show when they were released. Javad does go to town on his cabinet construction but a simple box construction can still be used.

https://www.facebook.com/hashtag/ceramicosspeakerbyjavadandjeff/?__gid__=462464294109413

Also, if you use the way back machine then Troel’s SBA761 (MW19 + MW16 + TW29RN) is on there with crossover values if you do a search. This is an interesting 2.5 way design using primarily 1st order acoustic crossovers.

Current web page - http://www.troelsgravesen.dk/SBA-761.htm there are a number of these built and shown in his “Builders Response Pages”.
 
#9
Any reason why you are restricting yourself to SB drivers,. The Philharmonic BMR looks to fit the bill generally. It can be made into a floor stander if you need, you may be able to reduced the depth a bit by doing this as well.

https://meniscusaudio.com/product/philharmonic-audio-bmr-speaker-kit/

One other option is to make the Kairos or Adelphos Two way (MW16P + TW29) and then add the bass module using the 29NRX but make it slim and put the driver on the side.

https://meniscusaudio.com/product/adelphos-speaker-kit/

Also there is the Troels SBA16 Satori MTM and the Jeff Bagby Adelphos MTM that would get you 90% of the three way in a simpler design and slimmer design.

I also think that fitting the SB23NRX (234mm diam) or similar 8" drivers onto the front of a 10" (254mm) cabinet is a bit of a squeeze leaving less than 10mm either side and the driver will overlap the inner cavity width by close to 10mm as you are likely to be using 18 or 21mm cabinet material.
 
#12
The SB23NRX45-8 needs a fairly large box for the size of the driver, probably 1.5-2.0cuft. Model it in Winisd and see how it goes, I think max flat alignment is nearer 2.75cuft with a 3”diam x 6”long port but it goes deep with an F3 of 29hz and an f10 of 22hz. If you go for a simple ported design then you could move the bass driver up to be underneath the mix/tweeter if that is aesthetically better. I also asked Paul Kittinger about another of his designs that had the rounded top and he suggested that going for a rectangular box would make only a slight difference.

Hope that helps a little.
 
#13
Ugg10 said:
I did find the Paul Kittinger Sonatello which uses the SB23NRX in a MLTL floor standing box but it is 1” wide, this may be the closest you get to your original spec.

https://www.diyaudio.com/community/threads/sb-acoustics-3-way-the-sonatello-speaker.323375/
Click to expand...
Actually the Sonatello has a tapered TL, not an ML-TL, for its SB woofer. The cabinet is 1 wider than desired but that's primarily because the SB woofer has a larger than usual diameter than most 8-inchers for its mounting flange.
Paul
 
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#15
I note Paul Kittinger is looking at this thread.
Can I ask Paul to comment regarding moving the bass unit up a little as I will be building this as a bass reflex.
Also with regard to the crossover is it OK to use all Jantzen air cores.
Also instead of the NPE a Jantzen Z cap and are Jantzen 10 watt Superes ok for the resistors.
In fact Coul I use Jantzen Z caps throughout.
Thanks for your help
Colin
 
#16
colmo said:
I note Paul Kittinger is looking at this thread.
Can I ask Paul to comment regarding moving the bass unit up a little as I will be building this as a bass reflex.
Also with regard to the crossover is it OK to use all Jantzen air cores.
Also instead of the NPE a Jantzen Z cap and are Jantzen 10 watt Superes ok for the resistors.
In fact Coul I use Jantzen Z caps throughout.
Thanks for your help
Colin
Click to expand...

colmo said:
Whether you're making just a ported box or ML-TL, moving either the woofer and/or port locations will affect the overall bass response shape which you can determine with modeling only if that modeling software takes into account internal dimensions and locations instead of just internal volume. Moving either a small amount, like under an inch, likely will not make much of a change, especially audibly.
Click to expand...
Paul
 
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#17
Hi Paul
Thanks for information regarding bass unit placement.
With regard to the crossover components I have discovered that Jantzen dont make an air core 4.0 mh but do an iron core 4.0mh coil with a resistance of 0.23 ohms. Not 0.22 ohms as specified but assume this will be ok.
Would still like to know if I could use Jantzen standard Z caps for all caps, not just the HF driver and if superes 10 watt resistors will be ok .
Is there a reason why C2 is an NPE
Thanks
Colin
 
#18
colmo said:
Hi Paul
Thanks for information regarding bass unit placement.
With regard to the crossover components I have discovered that Jantzen dont make an air core 4.0 mh but do an iron core 4.0mh coil with a resistance of 0.23 ohms. Not 0.22 ohms as specified but assume this will be ok.
Would still like to know if I could use Jantzen standard Z caps for all caps, not just the HF driver and if superes 10 watt resistors will be ok .
Is there a reason why C2 is an NPE
Thanks
Colin
Click to expand...
I used an Erse steel laminate inductor for L1 (4.0 mH). The resistance of the Jantzen iron-core 4.0 mH inductor would be fine, but an iron-core inductor may saturate more easily than the steel laminate and that would depend on how hard you drive the speaker and the musical content. Since C2 is in the woofer's crossover and large-value NPEs are generally acceptable in that application, I chose an NPE to have a smaller size and lower cost, but you certainly can use all Jantzen standard Z caps if you desire. I used Mills power resistors because they have high quality, are rated at 12 watts and are smaller than most 10-watt power resistors, but you can use typical 10-watt resistors if you want to. Have you decided to build the Sonatellos, and if so, as a tapered TL like mine or a ported box? If you do decide to build the Sonatellos as designed, I have quite a few photos I took during construction that I can share with you.
Paul
 
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#19
colmo said:
The Sonatello is a possibility but I want a bass reflex design, I suppose I could build as a bass reflex and reduce the front to rear dimension.
Click to expand...
I developed the simulation of a floorstander with SBA speakers for a friend of mine last winter. I have to say that my friends lives 1000 Km far away from my city and so I never had the possibility to carry out any measurements of the speakers and everything is based on the traced curves of the manufacturer.
Anyway, now the system has been completed and my friend is very satisfied.
The system is 3-way (8-5-1), the baffle is 25x97 cm and is a 40L bass reflex tuned at 38Hz. It is based on the PFCR line of SBA because the budget was under 500 € for speakers and filters components.
If you need more info feel free to ask.
1659710392469.png

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1659710109175.png
 
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#20
pkitt said:
I used an Erse steel laminate inductor for L1 (4.0 mH). The resistance of the Jantzen iron-core 4.0 mH inductor would be fine, but an iron-core inductor may saturate more easily than the steel laminate and that would depend on how hard you drive the speaker and the musical content. Since C2 is in the woofer's crossover and large-value NPEs are generally acceptable in that application, I chose an NPE to have a smaller size and lower cost, but you certainly can use all Jantzen standard Z caps if you desire. I used Mills power resistors because they have high quality, are rated at 12 watts and are smaller than most 10-watt power resistors, but you can use typical 10-watt resistors if you want to. Have you decided to build the Sonatellos, and if so, as a tapered TL like mine or a ported box? If you do decide to build the Sonatellos as designed, I have quite a few photos I took during construction that I can share with you.
Paul
Click to expand...
Hi Paul
Thanks again for all of your help.
I was looking up the Jantzen 4.0 mh coil and although they call it an Iron Core they say its actually a material called Permite and according to them is ideal for midrange and bass applications so I think it will be ok.
I have found one that is even closer at 0.215 ohms.
Withe regard to the placement of the bass unit I have a programme that shows the different room gains depending on how close the bass driver is to the floor, side wall and back wall which I can play with.
As a matter of interest how far from the side and back walls was the speaker designed to work best.
When I say back wall what distance from the back of the cabinet to the wall.
I am still intending to build it as a bass reflex with possibly a bottom port so I will get further gain there.
Thanks again
Colin
 
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