I have a pair of Radian Neo745PB compression drivers and a pair of Ciare PR614 Horns to mount them on and I am looking to building a 2 way system to complement them and finally give them a proper home.
I am in search of a woofer to start the design process and since I am located in Italy it makes sense to limit the field to the great speakers made here. 18 sound, RCF, B&C, Ciare, would be easy to source here. Here is my active list in a google sheet which your invited to add anything that might be of interest. LINK
How to go about marching a woofer to these compression drivers? I am open to suggestions but I was envisioning a 10" or 12" woofer. How does the response curve, the efficiency, the power handling guide the woofer selection?
The setup will be BI amped with some Powersoft Q3002's and I plan on doing active crossovers with a miniDSP or a rack mounted DSP such as a EV DC-ONE
The intended use is for a mix of home stereo, portable DJ setup, band practice, and just general PA usage. The plan is to add a sub at some point.
The budget is around 160EUR for each woofer.
Volume wise I dont have a hard constraint but something in the 40-55 liters sounds reasonable.
What other requirements or constraints am I missing to nail down a driver before moving to the cabinate design fase?
Thanks
I am in search of a woofer to start the design process and since I am located in Italy it makes sense to limit the field to the great speakers made here. 18 sound, RCF, B&C, Ciare, would be easy to source here. Here is my active list in a google sheet which your invited to add anything that might be of interest. LINK
How to go about marching a woofer to these compression drivers? I am open to suggestions but I was envisioning a 10" or 12" woofer. How does the response curve, the efficiency, the power handling guide the woofer selection?
The setup will be BI amped with some Powersoft Q3002's and I plan on doing active crossovers with a miniDSP or a rack mounted DSP such as a EV DC-ONE
The intended use is for a mix of home stereo, portable DJ setup, band practice, and just general PA usage. The plan is to add a sub at some point.
The budget is around 160EUR for each woofer.
Volume wise I dont have a hard constraint but something in the 40-55 liters sounds reasonable.
What other requirements or constraints am I missing to nail down a driver before moving to the cabinate design fase?
Thanks
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I also have a pair of those horns and two Radian 745Neo.
It is usually recommended to cross over where the directivity of the driver and horn match.
This will be a little different for each model driver in the same size class.
For a 12" this might be around 1.5Khz. You can also cross where they both lose pattern control. This would be roughly 800hz. I've tried both and I like the 800hz crossover more for the most part.
B&C seems to be pushing the NDL88 series these days. Not sure how much you can get them for. Nice balance between bass and efficiency. These would be a good choice for a wide variety of occasions where you still want some bass but don't need a sub.
Lots of drivers will work...it depends how low and how loud you want a 12" to go. Frequency response isn't too important as you'll be using dsp to fix broadband curves.
It is usually recommended to cross over where the directivity of the driver and horn match.
This will be a little different for each model driver in the same size class.
For a 12" this might be around 1.5Khz. You can also cross where they both lose pattern control. This would be roughly 800hz. I've tried both and I like the 800hz crossover more for the most part.
B&C seems to be pushing the NDL88 series these days. Not sure how much you can get them for. Nice balance between bass and efficiency. These would be a good choice for a wide variety of occasions where you still want some bass but don't need a sub.
Lots of drivers will work...it depends how low and how loud you want a 12" to go. Frequency response isn't too important as you'll be using dsp to fix broadband curves.
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Since you're located in Italy, look up Sica and Lavoce also. Sica have very price competitive products!
Thanks for the suggestions, @ErnieM and @peterbrorsson. The B&C 12NDL88 looks for like a great woofer to match these Radian Compression Drivers. I have found them at around 150 Euro each so they are within budget.
Apart from the specific woofer model. The question of choosing 12 inch over 10 inch is which? I know that bigger is always better (for low frequency response) but what are the advantages of going 10"? Is it since I have 1.4" diameter compression driver the woofer selection is veering the decision to 12" due to what ErnieM mentioned of where the directivity of the HF and LF meet?
can't wait to settle on a woofer to dive into the cabinet design, and asking more Noobie questions here.
Apart from the specific woofer model. The question of choosing 12 inch over 10 inch is which? I know that bigger is always better (for low frequency response) but what are the advantages of going 10"? Is it since I have 1.4" diameter compression driver the woofer selection is veering the decision to 12" due to what ErnieM mentioned of where the directivity of the HF and LF meet?
can't wait to settle on a woofer to dive into the cabinet design, and asking more Noobie questions here.
Am I missing something, but isn't Radian Neo745PB 2" throat and the Ciare PR614 horn 1.4" throat?
The Radian Neo745PB's are 1.4", but apparently the link I added in the first post links to the 760 which is 2"
You scared me there for a second.
Here are the correct specs https://cdn.shopify.com/s/files/1/0111/0324/0254/files/745NeoPB-data_sheet-final_070817.pdf?782
Only advantage of a 10" is box size. 12" is the sweet spot for a multi-purpose 2-way box.
That's a good price for the B&C. I haven't seen anything from the other brands that perform better for less money.
The components you have will be capable of high quality sound. The crossover and eq tuning will determine whether you have something outstanding or mediocre.
You will need some basic measurement software like ARTA and REW for best results.
That's a good price for the B&C. I haven't seen anything from the other brands that perform better for less money.
The components you have will be capable of high quality sound. The crossover and eq tuning will determine whether you have something outstanding or mediocre.
You will need some basic measurement software like ARTA and REW for best results.
Thanks ErnieM. Let's now assume that I do go with the B&C 12NDL88 woofer. On the B&C site they have a suggested design, the U12, https://www.bcspeakers.com/media/W1siZiIsIjIwMjEvMDMvMDEvMTJfMjVfMThfNjAyX1V0aWxpdHkxMi56aXAiXV0
Could just adapt this and call it good? Looks like a reasonably easy build. The only thing that I can think of is a difference in volume among the different horns and the compression drivers to be used. Also that the bracing that supports the compression driver will likely need some minor cut and location modifications.
Any thoughts?
Could just adapt this and call it good? Looks like a reasonably easy build. The only thing that I can think of is a difference in volume among the different horns and the compression drivers to be used. Also that the bracing that supports the compression driver will likely need some minor cut and location modifications.
Any thoughts?
With a 60 degree horn you might want to consider a 15" driver. You want to crossover somewhere around where the directivity of the woofer and tweeter match. For a 12" driver that would be around 1.5kHz. For a 15" driver that would be about 1.2kHz. It might be easier to find a 15" driver that extends out to 1.2kHz than a 12" driver that goes out to 1.5kHz. You might want to change horns to a 90 degree horn which would allow you to bring down the crossover frequency to 1kHz and 800Hz respectively (which your 1.4" Radian CD can easily handle).
The advantage of that Ciare horn is that its entry angle matches the exit angle of this Radian driver.
Does the crossover frequency really have to be where both ways have 60 degrees disperion ? One could also cross lower where both have wider dispersion. A definite no-go would be to cross higher up where the woofer has narrower radiation than the "tweeter".
Regards
Charles
Does the crossover frequency really have to be where both ways have 60 degrees disperion ? One could also cross lower where both have wider dispersion. A definite no-go would be to cross higher up where the woofer has narrower radiation than the "tweeter".
Regards
Charles
The U12 kit would work perfectly fine.
The Radian/Ciare combo can easily match or exceed the usable output of any direct radiating 12" (used between 80-850hz) when crossed around 850hz.
Sound kept improving the lower I crossed. Started at 1.5khz and ended up at 800hz when using a 12" midbass.
The Radian/Ciare combo can easily match or exceed the usable output of any direct radiating 12" (used between 80-850hz) when crossed around 850hz.
Sound kept improving the lower I crossed. Started at 1.5khz and ended up at 800hz when using a 12" midbass.
Generally sudden changes in directivity are to be avoided. When you have them you have to start making bad choices. If I aim for flat on-axis response the off axis is wrong making the power response wrong. If you aim for flat power response the on-axis sounds bad. You generally end up in a compromise situation where you don't have flat on-axis or power response. Now the speaker can still sound OK. In fact, you often see speakers that seem to measure poorly but subjectively sound OK.
If you try to lower the crossover frequency enough for both horn and direct driver to be wide you'll find you have to get quite low. That's OK as long as your CD can handle the abuse. In a home audio situation the 1.4" Radian CD can probably handle almost anything without damage (they're rugged beasts). However I would take a look at distortion measurements. You might find that distortion on the tweeter grows pretty quickly as you lower the crossover frequency.
Distortion looked good for a compression driver when I measured 121ish db @ one meter with a LR24 800hz crossover. No sudden spike on the low end.
Update. Been creating some saw dust in my garage the last few weeks. Amazing what a circular saw, a router and a drill can do. Here are some pictures of where i am currently.
I have a question about dampening material. I can't find the same exact polyester fiber material specified in the utility12 document but I found one that is a bit denser. Rather than the 30kg/m3 specified I polyester fiber material of the same thinkness that has a density of 50kg/m3.
What do you think? will this produce much of a difference? Any autoritative rules on dampening materials?
I have a question about dampening material. I can't find the same exact polyester fiber material specified in the utility12 document but I found one that is a bit denser. Rather than the 30kg/m3 specified I polyester fiber material of the same thinkness that has a density of 50kg/m3.
What do you think? will this produce much of a difference? Any autoritative rules on dampening materials?
Acousta-Stuf Polyfill was very effective in a 7 cubic foot ported cabinet with Altec 416. About 1/2 pound per cubic foot was used, per instructions for my type of cabinet, applied to one of each opposite wall using a spray adhesive. This made for about a 2" thickness in material.
It can be pulled apart and expanded, but if you keep as much together as a continuous piece it is easier to apply to the top and sides as it keeps its shape. Much easier and less messy to use than fiberglass.
I couldn't find density specifications, but tried it after reading several positive reviews. Instruction give amount to use based on cabinet type.
It can be pulled apart and expanded, but if you keep as much together as a continuous piece it is easier to apply to the top and sides as it keeps its shape. Much easier and less messy to use than fiberglass.
I couldn't find density specifications, but tried it after reading several positive reviews. Instruction give amount to use based on cabinet type.
How low could that horn/driver combo be crossed with my sealed Altec 416-8Bs if my Rythmik F12 subs came in at ~80Hz? How close to Fc 500Hz and still have zero sound quality issues?
https://josephcrowe.com/blogs/news/altec-416-8b-in-100l-sealed
The manufacturer's recommendation of a 800Hz minimum crossover frequency is enough indication that sound quality will suffer below.
The PR 614 horizontal and vertical coverage flip below 2.5kHz, and it's horizontal coverage has expanded from 60 to ~140 degrees at 800Hz, at 500 Hz it would be well over 180 degrees unless on a large flat baffle.
Yes, the horn does have impressively constant Hor. directivity. Averaging ~ 70 degrees out to 6kHz when crossed at 800Hz?
Can't make out the numbers on this plot, though. http://oem.ciare.com/ik_files/catalogo/img/450_horizontal_web.jpg
But given my midwoofer's H3 and IM distortion numbers https://josephcrowe.com/blogs/news/altec-416-8b-in-100l-sealed ,
wouldn't it be better to use a horn https://audiohorn.net/next-gen-bi-radial-horn/and 2" exit driver https://jblpro.com/en-US/product_documents/2450-pdf that could cross at 500Hz?
A horizontal coverage that has expanded from 60 degrees above 2.5kHz to ~140 degrees at 800Hz is not "impressively constant" if one is considering a lower crossover.
The throat exit size does not determine the low frequency performance of a driver, but if you prefer to cross your high frequency driver as low as 500Hz, a horn designed for output that low certainly would be better than one designed for use above 800Hz.
Another display of my gross ignorance: When horns are put in flat baffles is it always for the same reason that woofers (particularly for open baffle speakers) are, to at least prevent much of the waveform of the lower frequencies from being reflected off the wall behind them and cancelling? At the risk of asking-as I am hardly a math wiz-how is the size of that baffle calculated to effectively minimize that range of lower frequency cancellation?
And how does application of this use of horn and/or woofer baffling differ from what NicoB is pursuing here? https://audiohorn.net/x-shape-horn/
https://audiohorn.net/mid-range-beaming-and-narrowing/