First off, zero experience with speaker design. So thanks to any advice here.
Second, active xo is a xilica 40-80. So pretty capable I think.
Third, the speakers were all selected/ suggested by others... Design goal generally is to match another center with a ribbon tweeter. Same XO points. Sadly the designer passed away. Rick Craig.
Second, active xo is a xilica 40-80. So pretty capable I think.
Third, the speakers were all selected/ suggested by others... Design goal generally is to match another center with a ribbon tweeter. Same XO points. Sadly the designer passed away. Rick Craig.
Here is something I wrote in another thread to answer someone else who asked "how do I do this?. How do I design a 3-way speaker?"...
https://www.diyaudio.com/community/threads/new-home-3way-setup.394024/post-7222914
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Since you have already selected your drivers, the next step is to design a cabinet. There are two competing design goals, one is the cabinet's effect on bass response, and the other is the baffle layout and how it affects the radiation of the drivers.
1) I would use VituixCad to design the baffle. This means the height and width of the baffle, the size and spacing of the drivers, and the size/shape of the edge bevel/radius. At this step you will assume the drivers are "perfect pistons", and the crossover will be a hypothetical filter using idealized slopes and eq's.
2) Next you would try to design a box volume and box shape that incorporates your baffle design, and also provides the correct box volume for the woofers. If it is a vented box system, you will also need enough room in the cabinet for a vent. You should assume that the midrange will need 4 - 6 liters of box volume for itself.
You will probably have to go back and forth between steps 1) and 2) until you get the best compromise.
3) Build your cabinets. Some people build a single prototype cabinet from cheaper materials and do all their development work with it. Others accept the risk and go straight to a pair of final cabinets. You will have to decide how confident you are in your design.
4) After you install the drivers in the cabinets, make acoustical and impedance measurements of the drivers. At this point there is no crossover. For best results, you will make horizontal polar measurements from 0 to 180 degrees for each driver. The gated far field measurements are merged with near field measurements to get a composite response that is used in simulation.
5) Begin simulation using the measured impedance and the measured composite responses. Now is the point where you design your crossover.
6) When you are happy with the crossover simulation, you load your crossover filter into the DSP hardware.
7) Listen, measure, listen again... tweak if necessary.
Broadly speaking, this is your path to success.
======== ==========
If this process seems overwhelming to you, then it might be wise to start with something less complicated than a 3-way. In truth, your proposed system is actually a 4-way when we consider the subwoofer. That is a lot of complexity for a first project.
j.
https://www.diyaudio.com/community/threads/new-home-3way-setup.394024/post-7222914
======== ==========
Since you have already selected your drivers, the next step is to design a cabinet. There are two competing design goals, one is the cabinet's effect on bass response, and the other is the baffle layout and how it affects the radiation of the drivers.
1) I would use VituixCad to design the baffle. This means the height and width of the baffle, the size and spacing of the drivers, and the size/shape of the edge bevel/radius. At this step you will assume the drivers are "perfect pistons", and the crossover will be a hypothetical filter using idealized slopes and eq's.
2) Next you would try to design a box volume and box shape that incorporates your baffle design, and also provides the correct box volume for the woofers. If it is a vented box system, you will also need enough room in the cabinet for a vent. You should assume that the midrange will need 4 - 6 liters of box volume for itself.
You will probably have to go back and forth between steps 1) and 2) until you get the best compromise.
3) Build your cabinets. Some people build a single prototype cabinet from cheaper materials and do all their development work with it. Others accept the risk and go straight to a pair of final cabinets. You will have to decide how confident you are in your design.
4) After you install the drivers in the cabinets, make acoustical and impedance measurements of the drivers. At this point there is no crossover. For best results, you will make horizontal polar measurements from 0 to 180 degrees for each driver. The gated far field measurements are merged with near field measurements to get a composite response that is used in simulation.
5) Begin simulation using the measured impedance and the measured composite responses. Now is the point where you design your crossover.
6) When you are happy with the crossover simulation, you load your crossover filter into the DSP hardware.
7) Listen, measure, listen again... tweak if necessary.
Broadly speaking, this is your path to success.
======== ==========
If this process seems overwhelming to you, then it might be wise to start with something less complicated than a 3-way. In truth, your proposed system is actually a 4-way when we consider the subwoofer. That is a lot of complexity for a first project.
j.
The sub xo will be handled by the preamp. These are just the left and right speakers for my theater.
The 4080 - Yes 4 in 8 out. It's a pro audio digital processor with:
8 band parametric EQ per channel
31 band Graphic EQ per channel
Time Alignment and Transducer Alignment Delays
Compressor/Limiter on every output
Speaker Compensation EQ (post crossover)
The 4080 - Yes 4 in 8 out. It's a pro audio digital processor with:
8 band parametric EQ per channel
31 band Graphic EQ per channel
Time Alignment and Transducer Alignment Delays
Compressor/Limiter on every output
Speaker Compensation EQ (post crossover)
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I would reach lower for the XO of the 4" to the 8"...at least 200hz, but 130hz, should be fine as well. The 4 inch should still have plenty of headroom and you'll get a better image of vocals.
I forgot that when I did this, I had a vented 4" tuned to 70hz.... Depending on your expectations of headroom, you could still get away with it, in a sealed. You can make sure you have enough headroom if you used two 4" woofers to create an MTM section. I personally think this is a very desirable design choice but this may not be for you. If not an mtm, I would consider using a slightly larger woofer to make sure you can crossover in the lower register of the male voice (~85hz-180hz). I think 6" is the largest woofer one can generally use before running into issues of Center to Center spacing with a 1" dynamic tweeter.
Its good that everything remains vertically aligned but a slight offset of the whole alignment on the baffle is a thing too... when you can cross over within the 1/4 wavelength distance in regards to center to center, tweeter to midwoofer, I think offsetting the tweeter from the midwoofer is more forgiving and as long as the offset remains within that tolerance, it would only leave the physical distance on the baffle to speculate
If you are thinking two 4" stacked on top of each other, with the tweeter offset to the side of the group... I like that idea as long as staying within 1/4wl.
As you move the xo higher and the drivers begin to uncouple a null is created off axis... as you move the tweeter around the midwoofer you are aiming this null to various points as it relates to the sources... an horizontal offset would move the null towards the horizontal plane, issues on the horizontal plane stand out more to us....
If you are thinking two 4" stacked on top of each other, with the tweeter offset to the side of the group... I like that idea as long as staying within 1/4wl.
As you move the xo higher and the drivers begin to uncouple a null is created off axis... as you move the tweeter around the midwoofer you are aiming this null to various points as it relates to the sources... an horizontal offset would move the null towards the horizontal plane, issues on the horizontal plane stand out more to us....
It's an interesting question, since there is no definite answer.
There are two spacing issues, the MT spacing and the MM spacing. Offset tweeter helps reduce MM spacing which is the greater of the issues.
Camplo, I'm not fond of vertical issues so I wouldn't trade them sight unseen. Power might turn out to be better in general in an offset design, but sometimes only careful analysis of each reflection point will give the ultimate answer. Not suggesting it's an excercise for everyone though..
There are two spacing issues, the MT spacing and the MM spacing. Offset tweeter helps reduce MM spacing which is the greater of the issues.
Camplo, I'm not fond of vertical issues so I wouldn't trade them sight unseen. Power might turn out to be better in general in an offset design, but sometimes only careful analysis of each reflection point will give the ultimate answer. Not suggesting it's an excercise for everyone though..
You want to go from a plan for a complex build to the final product with no prototyping to evolve your design.gd luck you are going to need it.there are hundreds of variables,thousands of opions,and likes and dislikes and even more experts.my advice build a well documented design from a gd designer.