Hello all,
I am new to threads and being in an online community. But in my pursuit of a home theater speaker build, I have so many questions.
For a little background, I have a degree in Audio Engineering Technology from Purdue University. I am not new to audio projects at all, but I mainly have dealt with electronics, not acoustics. I recently took a speaker building class and learned great fundamentals, but I would like to know all about the speaker building process in more depth.
So, that is why I have purchased the Loudspeaker Design Cookbook, Intro to Loudspeaker Design, and Designing, Building, and Testing Your Own Speaker System.
While all these books have great and needed information, I am getting lost in the amount of info and have lost where my direction is. I am wondering if you all have any set of steps to follow for the design process, because I feel like I am getting way too ahead of myself.
For example, I am doing matching tower speakers for the front L/R. But all free simulation softwares, e.g. WinISD, tell me that a box with a lot of volume such as a tower is too much and will have significant peaks around the resonant frequency. But also, what about waveguides? I've seen so many different design for the inside of a tower speaker, but no analysis on them to really understand the concept. These are just a few of questions I cannot find answers to.
I know I am probably being vague and confusing, but once I get my direction in this I will have more specific questions and conversational points to bring up. Don't wanna dump too much on anyone at once haha.
I have attached my CAD drawings, which were made to show my brother how they will aesthetically look when they finished. For reference for you all as well.
Anyways, I would greatly appreciate any support and help in where to start in the mathematical side of design.
Thank you.
I am new to threads and being in an online community. But in my pursuit of a home theater speaker build, I have so many questions.
For a little background, I have a degree in Audio Engineering Technology from Purdue University. I am not new to audio projects at all, but I mainly have dealt with electronics, not acoustics. I recently took a speaker building class and learned great fundamentals, but I would like to know all about the speaker building process in more depth.
So, that is why I have purchased the Loudspeaker Design Cookbook, Intro to Loudspeaker Design, and Designing, Building, and Testing Your Own Speaker System.
While all these books have great and needed information, I am getting lost in the amount of info and have lost where my direction is. I am wondering if you all have any set of steps to follow for the design process, because I feel like I am getting way too ahead of myself.
For example, I am doing matching tower speakers for the front L/R. But all free simulation softwares, e.g. WinISD, tell me that a box with a lot of volume such as a tower is too much and will have significant peaks around the resonant frequency. But also, what about waveguides? I've seen so many different design for the inside of a tower speaker, but no analysis on them to really understand the concept. These are just a few of questions I cannot find answers to.
I know I am probably being vague and confusing, but once I get my direction in this I will have more specific questions and conversational points to bring up. Don't wanna dump too much on anyone at once haha.
I have attached my CAD drawings, which were made to show my brother how they will aesthetically look when they finished. For reference for you all as well.
Anyways, I would greatly appreciate any support and help in where to start in the mathematical side of design.
Thank you.
OK??...Firstly, is this to be used solely for watching movies & the likes?...or is it for music, of all sorts also? There is much overlap between the two.
Second, the severe lack of footprint area is of concern. Some 20 years or so ago, I had built something almost identical (Dual 6 1/2 inch, woofer, single tweeter DeAppolito configuration)...and it was OK, within its severe limitations.
But the pair were hard pressed at high volumes, & always seemed pushed to their limitations. This current fad of the tiny floorspace WAF tower configurations should be taken with a grain of salt...if your truly serious about sound reproduction, cast that 'slim-tower' out the window...make the room for a serious pair or don't.
Third, are we going to go two-way, three-way...four-way? Do you want to try to be "high efficiency", or are we going to be able to throw large amounts of power at it?
Remember, high power levels (200+W) equals relative higher costs & complexity(separate components). On the other hand, high efficiency brings lower costs & more flexibility.
-------------------------------------------------------------------Rick...........
Second, the severe lack of footprint area is of concern. Some 20 years or so ago, I had built something almost identical (Dual 6 1/2 inch, woofer, single tweeter DeAppolito configuration)...and it was OK, within its severe limitations.
But the pair were hard pressed at high volumes, & always seemed pushed to their limitations. This current fad of the tiny floorspace WAF tower configurations should be taken with a grain of salt...if your truly serious about sound reproduction, cast that 'slim-tower' out the window...make the room for a serious pair or don't.
Third, are we going to go two-way, three-way...four-way? Do you want to try to be "high efficiency", or are we going to be able to throw large amounts of power at it?
Remember, high power levels (200+W) equals relative higher costs & complexity(separate components). On the other hand, high efficiency brings lower costs & more flexibility.
-------------------------------------------------------------------Rick...........
IMO, the number one goal in home theater should be intelligibility. You've got to understand the dialogue or the ambiance/surround speakers are worthless.
That, without question, should be your immediate direction. After that you can worry about your surround speakers. When you watch movies your brain is working hard to process images, story line, and dialogue. It doesn't have enough overhead left over to process ambiance the way it can when you sit in a chair and concentrate on listening to stereo music.
You probably already know about the small room transition frequency but I posted an image because it's important. And because it will save you from building huge front, side, and rear speakers.
Floyd Toole wrote a book called Sound Reproduction. He explains the issues of home theater. He also built a sort of *practical ideal* home theater in his house. You can use it as a general model without spending the wheelbarrows full of cash it would take to buy his equipment.
The book: Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms (Audio Engineering Society Presents): Toole, Floyd E.: 9781138921368: Amazon.com: Books
His home theater: The Ultimate “Real World“ Home Theater and Listening Room
Alternatively, there's a subject matter expert named Earl Geddes who uses a different approach from Floyd in home theater. You could look him up to see what he does differently from Toole. The main difference is Toole uses wide directivity speakers whole Geddes uses narrow directivity speakers. Toole's approach is common, Geddes' is less common.
The frequency range of spoken voice: 80 to 180Hz for men, 165 to 255Hz for women. You will want to get that frequency range right. If you can get dialogue right everyone will LOVE your home theater.
That, without question, should be your immediate direction. After that you can worry about your surround speakers. When you watch movies your brain is working hard to process images, story line, and dialogue. It doesn't have enough overhead left over to process ambiance the way it can when you sit in a chair and concentrate on listening to stereo music.
You probably already know about the small room transition frequency but I posted an image because it's important. And because it will save you from building huge front, side, and rear speakers.
Floyd Toole wrote a book called Sound Reproduction. He explains the issues of home theater. He also built a sort of *practical ideal* home theater in his house. You can use it as a general model without spending the wheelbarrows full of cash it would take to buy his equipment.
The book: Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms (Audio Engineering Society Presents): Toole, Floyd E.: 9781138921368: Amazon.com: Books
His home theater: The Ultimate “Real World“ Home Theater and Listening Room
Alternatively, there's a subject matter expert named Earl Geddes who uses a different approach from Floyd in home theater. You could look him up to see what he does differently from Toole. The main difference is Toole uses wide directivity speakers whole Geddes uses narrow directivity speakers. Toole's approach is common, Geddes' is less common.
The frequency range of spoken voice: 80 to 180Hz for men, 165 to 255Hz for women. You will want to get that frequency range right. If you can get dialogue right everyone will LOVE your home theater.
Attachments
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Regarding multiple subs. Both Toole and Geddes use multiple subwoofers. Toole used JBL Sound Field Management in his home. Geddes used his own design. Geddes explains how to set up multiple subs here: Earl Geddes, Setting Up Multiple Subs, 2011.pdf - Google Drive
JBL sells the Sound Field Management algorithm to equalize multi subwoofers through their equipment, it's like how you buy Dolby or Dirac with a receiver at the store: SDEC-3500 | 8-channel Fully-balanced Digital Equalizer
If you don't want to do it yourself you can buy it from JBL.
JBL sells the Sound Field Management algorithm to equalize multi subwoofers through their equipment, it's like how you buy Dolby or Dirac with a receiver at the store: SDEC-3500 | 8-channel Fully-balanced Digital Equalizer
If you don't want to do it yourself you can buy it from JBL.
Greets!
Correct since you must use TL/horn design centric software such as the Hornresp freeware popular here: Hornresp
MJK's 1/4 WL site is THE compendium for TL theory, design: Quarter Wavelength Loudspeaker Design
Associated acoustic theory, though with your education it wouldn't surprise me if you're not already familiar with the site at least in general: Resonances of open air columns
GM
I designed them slim to meet the desires of my brothers basic design request. I have also seen speaker manufacturers make these slim style speakers and have heard them in a system. Working very well, I was shocked. For example the Klipsch tower speakers.
These speakers are going to be for everything, movies and entertainment, as well as all types of music.
I am going to go with a two-way design and I do think my brother will be pushing these speakers too hard.
Thank you all for the helpful links and references! I will for sure be looking into these the next fews days and taking notes.
FYI, I am not making a subwoofer for this setup. When the time comes, I will research one that is suitable for the setup.
At this time I feel like I have a good amount of knowledge to proceed, but no direction on where to start and go. As of now, I have all the drivers (which are listed below) and a rough design of the enclosures. But I do not know where to go from here.
I know I should find the volume of each box right now, but exactly how?
Then maybe find the tuning frequency, but I cannot find sources on how to properly obtain that.
A large question I am pondering on is that fact that Klipsch makes their tower speakers with nothing but bracing inside of them, and a port. Which amounts to a large volume for their drivers. Yet on WinISD, any volume close to that of a tower (~40liters) just insanely peaks at fs. So how do they get away with that?
Also, @bradleypnw, that makes a lot of sense and does help me with another key factor I need to take into consideration. But how do I make dialog more understandable? Is that determined by the tuning frequency and the cutoff? How can the design be done in order to better achieve understanding of the dialog?
FYI, I am not making a subwoofer for this setup. When the time comes, I will research one that is suitable for the setup.
At this time I feel like I have a good amount of knowledge to proceed, but no direction on where to start and go. As of now, I have all the drivers (which are listed below) and a rough design of the enclosures. But I do not know where to go from here.
I know I should find the volume of each box right now, but exactly how?
Then maybe find the tuning frequency, but I cannot find sources on how to properly obtain that.
A large question I am pondering on is that fact that Klipsch makes their tower speakers with nothing but bracing inside of them, and a port. Which amounts to a large volume for their drivers. Yet on WinISD, any volume close to that of a tower (~40liters) just insanely peaks at fs. So how do they get away with that?
Also, @bradleypnw, that makes a lot of sense and does help me with another key factor I need to take into consideration. But how do I make dialog more understandable? Is that determined by the tuning frequency and the cutoff? How can the design be done in order to better achieve understanding of the dialog?
In terms of process, the smartest thing you can do for both your benefit and those trying to help you is define your design criteria/goals as best you can to start off with. These would include but may not be limited to:
1. Budget: This can really narrow down driver selection and even whether you go 2-way or 3-way sometimes as a 3-way xo is usually at least twice as expensive as a 2-way.
2. Usage Considerations: So home theater. As mentioned intelligibility becomes paramount. Helpful is to go with a 3-way with a separate mid especially for the CC as the CC is just so important in HT. Drivers with a smoother response can help in this regard too. Also as close to a uniform FR across the front soundstage as possible, meaning the same drivers or drivers from the same family in the LRC speakers. Also helpful can be narrow directivity but consistent off-axis response which means a tweeter waveguide.
3. Speaker Impedance: Best to know from the start what the amp's minimum impedance is and make sure the speakers stay above that. Otherwise harm may ensue....
4. Maximum Cabinet Sizes: This seems to be sort of where you've started but it may help to know if these are your maximums or if there is some flexibility. Be aware there is a difference in talking about the net volume of the cabinet and the gross volume. Drivers with truncated frames can be beneficial especially for the CC where cabinet height may be most limited and the tweeter and mid(s) really should be placed one above the other (looks like you've got this one figured out).
5. Low Frequency Extension: Typically with a sub, the speakers only need an F3 of about 80Hz, often achievable in a sealed alignment. Without a sub, F3 near 30Hz may be an acceptable compromise. Even with a sub, L and R and even the CC with F3 of about 30Hz can be an advantage as it's close to multiple subs in the room which will usually result in a more uniform FR. Note though that 2-way, F3 near 30Hz and dialogue intelligibility are conflicting goals. Better achieved with a 3-way.
6. Max SPL (may affect speaker sensitivity and amp requirements): Typically we use xmax as the limit for a driver's max SPL. It will play louder but compression and distortion start to intrude. Max power ratings become important too. Higher sensitivity drivers and/or multiple drivers can be helpful here especially if you don't have a monster HT receiver. THX SPL levels I think are a little stupid but shooting for clean peaks of 105dB at 1m or even 110dB aren't that unreasonable. (just in case: 2 of the same drivers wired in parallel give +6dB; and doubling amp wattage is required for every 3dB increase in SPL)
7. Type of Speaker: This may follow from #'s 1, 2 and 5 above. Here I'm talking about sealed vs vented vs transmission line vs open back etc. Plus TM, MTM, TMW, MTMWW etc choices. May be affected by your ability/experience level.
8. Driver Selection: Sometimes a design will follow from the driver choices and sometimes the drivers will follow from the design choices. Your's is more the latter case.
9. Room Size and Speaker Placement: Both can affect the design and driver choice. Room size can affect the LF alignment and speaker placement can affect baffle step loss and therefore max SPL and therefore driver choice. And certainly the xo design.
10. Level of Difficulty vs Experience/Ability: 3-ways are definitely more difficult than a 2-way and are generally not the place to start for newbies. I have seen the occasional rare exception though with sufficient guidance. Up to you to make the call. Your CC design suggests you are willing to go all in. I'm sure many here will recommend going with a proven design though. Again, your call. After making design choices and getting help with the designs, the place to start for you might actually be with the simpler TM (or perhaps MTM) surround speakers.
Clarify/establish as many of the above as possible or appropriate for you and then we can start to make some informed recommendations.
After this, the process generally goes something like the following:
- choose/model your drivers
- determine driver layout and model baffle diffraction
- construct your frd and zma files
- simulate a potential xo. Start over if the drivers don't work well together.
- design and build the cabinets. Some will build test cabinets first.
- measure the in-cabinet driver responses
- design the xo with the measured responses
- listen, tweak and repeat until satisfied
Although not quite complete, this thread goes over much of the above in much more detail: So you want to design your own speaker from scratch!
In terms of your cabinet designs, the CC looks the most problematic. I think you are going to need more height to fit appropriate drivers, if those are 2 mids they are better off closer together and I don't think you will need 4 of the woofers; 2 will probably suffice. But that all depends on design criteria and then driver choices.
MTM could be a good choice for the L and R but without a sub and for other reasons stated above, I think I'd be going 3-way. But again, depends on all the design criteria you decide upon.
1. Budget: This can really narrow down driver selection and even whether you go 2-way or 3-way sometimes as a 3-way xo is usually at least twice as expensive as a 2-way.
2. Usage Considerations: So home theater. As mentioned intelligibility becomes paramount. Helpful is to go with a 3-way with a separate mid especially for the CC as the CC is just so important in HT. Drivers with a smoother response can help in this regard too. Also as close to a uniform FR across the front soundstage as possible, meaning the same drivers or drivers from the same family in the LRC speakers. Also helpful can be narrow directivity but consistent off-axis response which means a tweeter waveguide.
3. Speaker Impedance: Best to know from the start what the amp's minimum impedance is and make sure the speakers stay above that. Otherwise harm may ensue....
4. Maximum Cabinet Sizes: This seems to be sort of where you've started but it may help to know if these are your maximums or if there is some flexibility. Be aware there is a difference in talking about the net volume of the cabinet and the gross volume. Drivers with truncated frames can be beneficial especially for the CC where cabinet height may be most limited and the tweeter and mid(s) really should be placed one above the other (looks like you've got this one figured out).
5. Low Frequency Extension: Typically with a sub, the speakers only need an F3 of about 80Hz, often achievable in a sealed alignment. Without a sub, F3 near 30Hz may be an acceptable compromise. Even with a sub, L and R and even the CC with F3 of about 30Hz can be an advantage as it's close to multiple subs in the room which will usually result in a more uniform FR. Note though that 2-way, F3 near 30Hz and dialogue intelligibility are conflicting goals. Better achieved with a 3-way.
6. Max SPL (may affect speaker sensitivity and amp requirements): Typically we use xmax as the limit for a driver's max SPL. It will play louder but compression and distortion start to intrude. Max power ratings become important too. Higher sensitivity drivers and/or multiple drivers can be helpful here especially if you don't have a monster HT receiver. THX SPL levels I think are a little stupid but shooting for clean peaks of 105dB at 1m or even 110dB aren't that unreasonable. (just in case: 2 of the same drivers wired in parallel give +6dB; and doubling amp wattage is required for every 3dB increase in SPL)
7. Type of Speaker: This may follow from #'s 1, 2 and 5 above. Here I'm talking about sealed vs vented vs transmission line vs open back etc. Plus TM, MTM, TMW, MTMWW etc choices. May be affected by your ability/experience level.
8. Driver Selection: Sometimes a design will follow from the driver choices and sometimes the drivers will follow from the design choices. Your's is more the latter case.
9. Room Size and Speaker Placement: Both can affect the design and driver choice. Room size can affect the LF alignment and speaker placement can affect baffle step loss and therefore max SPL and therefore driver choice. And certainly the xo design.
10. Level of Difficulty vs Experience/Ability: 3-ways are definitely more difficult than a 2-way and are generally not the place to start for newbies. I have seen the occasional rare exception though with sufficient guidance. Up to you to make the call. Your CC design suggests you are willing to go all in. I'm sure many here will recommend going with a proven design though. Again, your call. After making design choices and getting help with the designs, the place to start for you might actually be with the simpler TM (or perhaps MTM) surround speakers.
Clarify/establish as many of the above as possible or appropriate for you and then we can start to make some informed recommendations.
After this, the process generally goes something like the following:
- choose/model your drivers
- determine driver layout and model baffle diffraction
- construct your frd and zma files
- simulate a potential xo. Start over if the drivers don't work well together.
- design and build the cabinets. Some will build test cabinets first.
- measure the in-cabinet driver responses
- design the xo with the measured responses
- listen, tweak and repeat until satisfied
Although not quite complete, this thread goes over much of the above in much more detail: So you want to design your own speaker from scratch!
In terms of your cabinet designs, the CC looks the most problematic. I think you are going to need more height to fit appropriate drivers, if those are 2 mids they are better off closer together and I don't think you will need 4 of the woofers; 2 will probably suffice. But that all depends on design criteria and then driver choices.
MTM could be a good choice for the L and R but without a sub and for other reasons stated above, I think I'd be going 3-way. But again, depends on all the design criteria you decide upon.
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The above posts are all chocked full of very good advice and some good references. Let me add a couple suggestions/observations from an old engineer:
1. Figure out what your goals are for this project and perhaps more importantly what they are *not*. You need to focus on accomplishing/delivering the former and avoid straying into the latter. Remember those lab exercises you did and the reports you wrote back in school? Usually the first section was entitled "Purpose" - there was a reason for that (*). Your stated goal here is to build an HT system. It is not to design the next great fully original pair of amazing 3-way speakers. Remember this.
2. This is your first HT system. If you are pursuing a career in the audio industry (and it sounds like you are) it will definitely not be your last. Face the fact now and accept that it will not be perfect. As time progresses and you develop experience your second one will be better and so on. It's a learning process.
3. With the above in mind - for your first system: Keep It Simple Stupid. I would recommend going initially with established speaker designs (you said that you just took a course in speaker building?). Remember that a good 2-way is better than a mediocre 3-way. Use subs. Don't try and get fancy or clever - save that for later. The skill and patience necessary to build a nice looking set of speaker enclosures (all 6-10 of them) will be enough of a challenge at this point.
4. Read up on acoustics. I am somewhat puzzled that an audio engineering degree did not have a fairly thorough coverage of room and venue acoustics. They are important. As references personally I like Everest and Pohlmann's "Master Handbook of Acoustics". I've also heard good things about Floyd Toole's "Sound Reproduction" (mentioned in a earlier post) but I have not personally read it (on my ToDo list). Also at this point you may want to seriously consider investing in a decent measurement setup (a good calibrated microphone, etc.) and get used to using it.
Good luck,
-bill
(*) Lab report sections: Purpose, Procedure, Results, Analysis, Conclusion - it's still a good way to approach many types of problems.
1. Figure out what your goals are for this project and perhaps more importantly what they are *not*. You need to focus on accomplishing/delivering the former and avoid straying into the latter. Remember those lab exercises you did and the reports you wrote back in school? Usually the first section was entitled "Purpose" - there was a reason for that (*). Your stated goal here is to build an HT system. It is not to design the next great fully original pair of amazing 3-way speakers. Remember this.
2. This is your first HT system. If you are pursuing a career in the audio industry (and it sounds like you are) it will definitely not be your last. Face the fact now and accept that it will not be perfect. As time progresses and you develop experience your second one will be better and so on. It's a learning process.
3. With the above in mind - for your first system: Keep It Simple Stupid. I would recommend going initially with established speaker designs (you said that you just took a course in speaker building?). Remember that a good 2-way is better than a mediocre 3-way. Use subs. Don't try and get fancy or clever - save that for later. The skill and patience necessary to build a nice looking set of speaker enclosures (all 6-10 of them) will be enough of a challenge at this point.
4. Read up on acoustics. I am somewhat puzzled that an audio engineering degree did not have a fairly thorough coverage of room and venue acoustics. They are important. As references personally I like Everest and Pohlmann's "Master Handbook of Acoustics". I've also heard good things about Floyd Toole's "Sound Reproduction" (mentioned in a earlier post) but I have not personally read it (on my ToDo list). Also at this point you may want to seriously consider investing in a decent measurement setup (a good calibrated microphone, etc.) and get used to using it.
Good luck,
-bill
(*) Lab report sections: Purpose, Procedure, Results, Analysis, Conclusion - it's still a good way to approach many types of problems.
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I would favor spending today's budget and the wood-work effort on a full range(30-20kHz) 3-way stereo pair of TMWW front speakers. 1"dome + sealed 6" midrange + two ported 8" woofers = a popular balanced topology. Tall 10" wide cabinet to support the volume required by two ported 8" woofers. Commit to great sound, or just go to CraigsList for good used HT speakers. Matching center + rear speakers can be built later.
Dennis Murphy in the htforum documents a TMWW using low cost Dayton drivers. The center channel W-T&M-W used a modest sealed volume vertical T-M stack with one 8" woofer on each side. A ported vertical T-M stack is more common.
Great HT needs impact, plus crisp details to identify direction and height. Several positive reviews recommend the medium cost aluminun cone drivers from SB_Acoustics. A step above the Dayton drivers. I would favor these drivers.
=1" dome SB26ADC-C000-4
=silver cone SB17NAC35-4 or black cone SB17NBAC35-4 midbass
=silver cone SB23NAC45-8 or black cone SB23NBAC45-8 woofer-pair
The woodshop capability often sets the design direction.
1) simple cuts with about 0.5" radius on front baffle edges
2) stepped front baffle for T-M time alignment, and 0.5" radius on front baffle
3) Avalon style truncated pyramid front baffle
There are good passive crossovers available, but a DSP crossover could be part of your career in the audio industry.
Dennis Murphy in the htforum documents a TMWW using low cost Dayton drivers. The center channel W-T&M-W used a modest sealed volume vertical T-M stack with one 8" woofer on each side. A ported vertical T-M stack is more common.
Great HT needs impact, plus crisp details to identify direction and height. Several positive reviews recommend the medium cost aluminun cone drivers from SB_Acoustics. A step above the Dayton drivers. I would favor these drivers.
=1" dome SB26ADC-C000-4
=silver cone SB17NAC35-4 or black cone SB17NBAC35-4 midbass
=silver cone SB23NAC45-8 or black cone SB23NBAC45-8 woofer-pair
The woodshop capability often sets the design direction.
1) simple cuts with about 0.5" radius on front baffle edges
2) stepped front baffle for T-M time alignment, and 0.5" radius on front baffle
3) Avalon style truncated pyramid front baffle
There are good passive crossovers available, but a DSP crossover could be part of your career in the audio industry.
Attachments
Great advice. I must confess that my main system is optimized for music, but I spend more hours watching movies on it than listening to music. I get an excellent "home theatre" experience from a simple stereo pair of high performance speakers. When the movie is good, you don't miss the surround effects.
Hi. LineSource!
I'm a noob.Could you post a link of the available passive crossovers for this build? Also,what kind of amp would be required to drive them. Just curious
First of all, thank you all again for such great advice and guidance. Since graduation and now covid, I have never been on an online forum for advice. So, this has been encouraging with so many audio fanatics and engineers willing to lend help. I have definitely been convinced to go with an established speaker design, which is honestly helpful. Realizing that my experience level is not where it should be for a too ambitious design at this stage in my life is humbling. I will be saving that for later, thank you wrankin.
Also, I do want to say that my shop capability is not limited in any fashion. I have been a woodworker since I was young. My grandfather had a great shop in his garage I did projects in when I was young; I have worked construction in remodeling for my Uncle; and have been doing various woodworking project for friends, family, and consumers for a long time. Even though it might not seem like a long time for some since I am only in my 20s haha. Though there is always more to learn!!
I said before I would tell you the drivers I already have, and I forgot so here they are.
Front and Rear L/R:
- Dayton Audio RS150P-8A 6” Reference Paper Woofer 8 ohm
- Dayton Audio DC28FS-8 1-1/8” Silk Dome Shielded Tweeter
Center Speaker:
- Dayton Audio RS100P-8 4” Reference Paper Midwoofer 8ohm
- Dayton Audio RS75T-8 3” Reference Full-Range Driver Truncated Frame
- Dayton Audio DC28FT-8 1-1/8” Silk Dome Truncated Tweeter
In regard to jReave:
1. Budget: The budget is pretty high; I do not know the exact number given by my brother. Yet, he is always willing to add more to the budget for help in the process. Obviously, it is not limitless of course.
2. Usage Considerations: I have considered voicing for the L/R and the CC with choosing the same woofers and tweeter. Only difference is that woofers are smaller for the CC and the tweeter is truncated to fit better in a shorter CC design. As said many times, a 3-way design is more difficult, and I would rather begin in a 2-way design for my fronts and rears.
Yet, on another note. I have read that to help with dead spots in the horizontal listening field for a CC, midrange drivers under the tweeter will help. But, how to I design that with the xo points that will be different from the L/R xo points due to the mid-range drivers in the CC?
3. Speaker Impedance: The receiver I have recommended to my brother for this is the Denon AVR-S750H. Which has a minimum impedance of 6 ohms @ 110W. Yet, it seems like the receiver will compensate to any load requirement that is plugged in to change the power output. So, he will not be able to crank these too loud since the woofer have an RMS power handling at 40 watts.
4. Maximum Cabinet Sizes: There is some flexibility to the size, yet my brother has requested that I keep them to a minimum is possible. Also, what is the difference of the net volume vs. the gross volume of a speaker?
5. Low Frequency Extension: There will be a sub, yet I am not making one for him. So, my f3 does not need to be so low. Yet, I have not figured out my f3 point yet.
6. Max SPL: I honestly do not know how to incorporate this into my design. Based in the woofer spec sheet, and the face that I will wire them in parallel. The max SPL would be around 95dB.
7. Type of Speaker: I am hopefully shooting for a vented design. Mainly because I have really enjoyed the sound of them in the past. But I am not set on that yet. I do not know where/how to find out why I would want to go either way.
8. Driver Selection: In this case, the design will follow from the driver choices.
9. Room Size and Speaker Placement: My brother is currently in a move to Texas and is in an apartment now but would like to move into a house soon. So, room size is unknown. Placement is very important, yet I will be across the country when he set’s these up in his place. So, I will do my best to try and see what the best options for placement are through facetime. Unfortunately, these two parameters cannot be controlled for the design.
10. Level of Difficulty vs Experience/Ability: I guess my first thought was going with a proven design. My initial thought was the tower speaker of Klipsch. Which are tall, narrow, ported, and have only bracing on the inside. As well as the basic TW box design for the rears. The CC is a mystery for me right now, I had an MTM design first, but my brother wanted it longer with more speakers. So I did some research to find the design I have now. Yet, with no numbers or anything to back up that design.
Also, what are the frd and zma files you are talking about. If there is a free (or inexpensive) software to help me with these would love to know! I am currently trying to find a speaker simulation software that will help me.
If there is a site or somewhere where I can browse through established designs, that would also be very helpful!
Thank you all,
Keil
Also, I do want to say that my shop capability is not limited in any fashion. I have been a woodworker since I was young. My grandfather had a great shop in his garage I did projects in when I was young; I have worked construction in remodeling for my Uncle; and have been doing various woodworking project for friends, family, and consumers for a long time. Even though it might not seem like a long time for some since I am only in my 20s haha. Though there is always more to learn!!
I said before I would tell you the drivers I already have, and I forgot so here they are.
Front and Rear L/R:
- Dayton Audio RS150P-8A 6” Reference Paper Woofer 8 ohm
- Dayton Audio DC28FS-8 1-1/8” Silk Dome Shielded Tweeter
Center Speaker:
- Dayton Audio RS100P-8 4” Reference Paper Midwoofer 8ohm
- Dayton Audio RS75T-8 3” Reference Full-Range Driver Truncated Frame
- Dayton Audio DC28FT-8 1-1/8” Silk Dome Truncated Tweeter
In regard to jReave:
1. Budget: The budget is pretty high; I do not know the exact number given by my brother. Yet, he is always willing to add more to the budget for help in the process. Obviously, it is not limitless of course.
2. Usage Considerations: I have considered voicing for the L/R and the CC with choosing the same woofers and tweeter. Only difference is that woofers are smaller for the CC and the tweeter is truncated to fit better in a shorter CC design. As said many times, a 3-way design is more difficult, and I would rather begin in a 2-way design for my fronts and rears.
Yet, on another note. I have read that to help with dead spots in the horizontal listening field for a CC, midrange drivers under the tweeter will help. But, how to I design that with the xo points that will be different from the L/R xo points due to the mid-range drivers in the CC?
3. Speaker Impedance: The receiver I have recommended to my brother for this is the Denon AVR-S750H. Which has a minimum impedance of 6 ohms @ 110W. Yet, it seems like the receiver will compensate to any load requirement that is plugged in to change the power output. So, he will not be able to crank these too loud since the woofer have an RMS power handling at 40 watts.
4. Maximum Cabinet Sizes: There is some flexibility to the size, yet my brother has requested that I keep them to a minimum is possible. Also, what is the difference of the net volume vs. the gross volume of a speaker?
5. Low Frequency Extension: There will be a sub, yet I am not making one for him. So, my f3 does not need to be so low. Yet, I have not figured out my f3 point yet.
6. Max SPL: I honestly do not know how to incorporate this into my design. Based in the woofer spec sheet, and the face that I will wire them in parallel. The max SPL would be around 95dB.
7. Type of Speaker: I am hopefully shooting for a vented design. Mainly because I have really enjoyed the sound of them in the past. But I am not set on that yet. I do not know where/how to find out why I would want to go either way.
8. Driver Selection: In this case, the design will follow from the driver choices.
9. Room Size and Speaker Placement: My brother is currently in a move to Texas and is in an apartment now but would like to move into a house soon. So, room size is unknown. Placement is very important, yet I will be across the country when he set’s these up in his place. So, I will do my best to try and see what the best options for placement are through facetime. Unfortunately, these two parameters cannot be controlled for the design.
10. Level of Difficulty vs Experience/Ability: I guess my first thought was going with a proven design. My initial thought was the tower speaker of Klipsch. Which are tall, narrow, ported, and have only bracing on the inside. As well as the basic TW box design for the rears. The CC is a mystery for me right now, I had an MTM design first, but my brother wanted it longer with more speakers. So I did some research to find the design I have now. Yet, with no numbers or anything to back up that design.
Also, what are the frd and zma files you are talking about. If there is a free (or inexpensive) software to help me with these would love to know! I am currently trying to find a speaker simulation software that will help me.
If there is a site or somewhere where I can browse through established designs, that would also be very helpful!
Thank you all,
Keil
Your post has me confused. On the 1 hand, you think that going with a proven design is the way forward and then on the other hand, you are asking questions about how to design something yourself. 
Also if you are going to go with a proven design, are you thinking of trying to use the drivers you already have or are you open to going with completely new ones? Because unfortunately the likelihood of finding a pre-designed HT system based around the drivers you already have is probably close to nil.
For smaller HT systems, 3 proven designs come to mind:
1. Zaph's ZA5 collection which offers excellent options to choose from
2. Paul C's Speedsters (plus CC and TMM)
3. Paul C's Swopes
Complete HT systems are actually a little more hard to come by in the diy world so hopefully others might have more to recommend if this is the way you want to go.
To answer some of your questions:
You have to design the xo points that are correct for each set of drivers so yes the CC will be different than the L&R. It's a compromise to the unity of the front soundstage if you want MTM's for the L&R and W(T/M)W for the CC but not the worst thing in the world there are advantages to a CC W(T/M)W if it's done well.
Gross volume is the entire volume of space inside the cabinet. Net volume is the gross volume minus all the other solids inside the cabinet, like bracing, drivers, ports including the air space inside them, xo's, etc. It is the net volume that a driver will 'see' in terms of its alignment and it is always the net volume that box modeling software is showing you.
With a sub, F3 needs only be low enough so that the sub becomes difficult to localize where it's positioned. This is typically at about 80Hz. So technically that's all you need for F3 for all your HT speakers. There are advantages to having LF produced at multiple locations in a room though so going with multiple subs or getting deep bass extension out of any or all of the speakers doesn't hurt. Doesn't quite fit with your smaller cabinet size restriction though since lower F3 usually requires larger drivers and/or cabinets.
Each driver will have a maximum SPL based on xmax or max power rating for the voice coil, the alignment you choose for it and/or the xo frequency you choose for it. Your whole system max SPL would therefore be defined by the driver(s) with the lowest max SPL.
The RS150P-8A can take 40W of power which would be just over 110dB at 1m for 2 of them in parallel. If you put 2 of them in parallel in a 16L vented box tuned to 60Hz, F3 will also be about 60Hz but max SPL will only be about 107dB at 1m because xmax will be exceeded when it's asked to play content below 50Hz. And that happens with only 20W. In the HT receiver, the sub xo point for these speakers should therefore be set at about 50-60Hz and then you'd probably be safe with the extra 20W and the extra 3dB that will get you.
But looking at the RS150 is a little moot because it's going to be either the RS75 with a 15W max or the RS100P at 30W max that are going to have a lower max SPL limit. Depends on the placement of the CC though and whether the full 6dB of baffle step compensation is needed on the RS100's. Max SPL for 2 of the RS75 in parallel is 101dB as long as they are crossed over above at least about 400Hz so that xmax is not exceeded. Max SPL for the RS100 in 10L vented is 103dB at 1m with 15W because of xmax limits. If you lose 6dB to baffle step compensation, that's now 97dB max.
For HT in an apartment, a max SPL of about 90-95dB at the listening position I think would suffice. Because, neighbors. That's about 80-85dB for dialogue etc and 10dB for effects peaks. For HT in a house and/or a dedicated HT room, the target should be higher than that.
Note that as you move away from a speaker, the SPL diminishes. In an enclosed room it's about 3-4dB every time you double the distance. So if you start with 100dB at 1m, at 2m you are down to about 96dB and at 3m you are down to about 93-94dB. So I would say that your selected drivers work in an apartment but wouldn't suffice for higher SPL venues.
Btw all driver and box calculations were done with Unibox.
Personal preference is a perfectly adequate reason for some design decisions. Sometimes though, one design criteria can depend on another. Put the RS150 in a 5L sealed box and the F3 is only going to be about 125Hz so that doesn't work as it fails to meet the minimum F3 design goal of 80Hz. So that driver must be ported.
Put a single RS100 in a 2 or 3L sealed and F3 will be about 134Hz. Ported in about 5L tuned to 71Hz will get you an F3 of about 61Hz. So again this one must be ported.
The RS75 would be in a 3-way so they only need an F3 low enough for a xo point probably somewhere around 500Hz +/-. That's fine in a small sealed box of about 2-3L for each driver.
It's not so much about controlling them. It's about accounting for them. Because HT receivers have built in eq these days, I suppose it's not absolutely essential but normally you need to know about speaker placement in order to properly design for baffle step compensation and in the case of a CC ensconced in something like a console cubbyhole, to try to simulate more accurate baffle diffraction responses too.
More info on the topic here and here.
These are the names for the type of files that are used by most free speaker design software programs. One is for the frequency response and the other is for the impedance response. I'll try a 2nd time to get you to read this thread: So you want to design your own speaker from scratch!. It will answer many of your questions in more detail than I have (and this is a long enough post already
).
Also if you are going to go with a proven design, are you thinking of trying to use the drivers you already have or are you open to going with completely new ones? Because unfortunately the likelihood of finding a pre-designed HT system based around the drivers you already have is probably close to nil.
For smaller HT systems, 3 proven designs come to mind:
1. Zaph's ZA5 collection which offers excellent options to choose from
2. Paul C's Speedsters (plus CC and TMM)
3. Paul C's Swopes
Complete HT systems are actually a little more hard to come by in the diy world so hopefully others might have more to recommend if this is the way you want to go.
To answer some of your questions:
You have to design the xo points that are correct for each set of drivers so yes the CC will be different than the L&R. It's a compromise to the unity of the front soundstage if you want MTM's for the L&R and W(T/M)W for the CC but not the worst thing in the world there are advantages to a CC W(T/M)W if it's done well.
Gross volume is the entire volume of space inside the cabinet. Net volume is the gross volume minus all the other solids inside the cabinet, like bracing, drivers, ports including the air space inside them, xo's, etc. It is the net volume that a driver will 'see' in terms of its alignment and it is always the net volume that box modeling software is showing you.
With a sub, F3 needs only be low enough so that the sub becomes difficult to localize where it's positioned. This is typically at about 80Hz. So technically that's all you need for F3 for all your HT speakers. There are advantages to having LF produced at multiple locations in a room though so going with multiple subs or getting deep bass extension out of any or all of the speakers doesn't hurt. Doesn't quite fit with your smaller cabinet size restriction though since lower F3 usually requires larger drivers and/or cabinets.
Each driver will have a maximum SPL based on xmax or max power rating for the voice coil, the alignment you choose for it and/or the xo frequency you choose for it. Your whole system max SPL would therefore be defined by the driver(s) with the lowest max SPL.
The RS150P-8A can take 40W of power which would be just over 110dB at 1m for 2 of them in parallel. If you put 2 of them in parallel in a 16L vented box tuned to 60Hz, F3 will also be about 60Hz but max SPL will only be about 107dB at 1m because xmax will be exceeded when it's asked to play content below 50Hz. And that happens with only 20W. In the HT receiver, the sub xo point for these speakers should therefore be set at about 50-60Hz and then you'd probably be safe with the extra 20W and the extra 3dB that will get you.
But looking at the RS150 is a little moot because it's going to be either the RS75 with a 15W max or the RS100P at 30W max that are going to have a lower max SPL limit. Depends on the placement of the CC though and whether the full 6dB of baffle step compensation is needed on the RS100's. Max SPL for 2 of the RS75 in parallel is 101dB as long as they are crossed over above at least about 400Hz so that xmax is not exceeded. Max SPL for the RS100 in 10L vented is 103dB at 1m with 15W because of xmax limits. If you lose 6dB to baffle step compensation, that's now 97dB max.
For HT in an apartment, a max SPL of about 90-95dB at the listening position I think would suffice. Because, neighbors. That's about 80-85dB for dialogue etc and 10dB for effects peaks. For HT in a house and/or a dedicated HT room, the target should be higher than that.
Note that as you move away from a speaker, the SPL diminishes. In an enclosed room it's about 3-4dB every time you double the distance. So if you start with 100dB at 1m, at 2m you are down to about 96dB and at 3m you are down to about 93-94dB. So I would say that your selected drivers work in an apartment but wouldn't suffice for higher SPL venues.
Btw all driver and box calculations were done with Unibox.
Personal preference is a perfectly adequate reason for some design decisions. Sometimes though, one design criteria can depend on another. Put the RS150 in a 5L sealed box and the F3 is only going to be about 125Hz so that doesn't work as it fails to meet the minimum F3 design goal of 80Hz. So that driver must be ported.
Put a single RS100 in a 2 or 3L sealed and F3 will be about 134Hz. Ported in about 5L tuned to 71Hz will get you an F3 of about 61Hz. So again this one must be ported.
The RS75 would be in a 3-way so they only need an F3 low enough for a xo point probably somewhere around 500Hz +/-. That's fine in a small sealed box of about 2-3L for each driver.
It's not so much about controlling them. It's about accounting for them. Because HT receivers have built in eq these days, I suppose it's not absolutely essential but normally you need to know about speaker placement in order to properly design for baffle step compensation and in the case of a CC ensconced in something like a console cubbyhole, to try to simulate more accurate baffle diffraction responses too.
More info on the topic here and here.
These are the names for the type of files that are used by most free speaker design software programs. One is for the frequency response and the other is for the impedance response. I'll try a 2nd time to get you to read this thread: So you want to design your own speaker from scratch!. It will answer many of your questions in more detail than I have (and this is a long enough post already
).
That is my bad @jReave, I understand how that can be confusing. I guess my thought was to use a proven design for how the inside is designed. I am still asking questions because I am very curious on certain decisions and I just want to learn more about everything I can. I am just asking all questions that run through my mind. I greatly appreciate the patience with me.
But I guess I am in a pickle. I do already have my drivers, yet I do want to do a proven design. I am still realizing new things and thinking about this a lot as I go. Though, I know that I already have made a few sets of speakers before and I’m ready to pull a lot of inspiration from proven designs and not try to ‘make the next great thing’. I already know a good amount, but I want to know more. That is why I will not 100% be going with a proven design. Because I want to push myself and challenge myself, which will help me learn. I’m not expecting greatness with this; I want to learn from my mistakes.
So, in conclusion, I would like to fully understand proven designs. About their volume, tuning frequency, volume, specific things they do for bracing or waveguides, their ports, and just everything. I want to learn all about them and lay it all out on the table. Then see what I would like to do with my design.
So, about the xo points for the CC, I have heard everywhere that the xo points of the L/R and the CC should always be the same to match the voicing. So, is it possible to have different xo points in the CC and the L/R, but still have the voicing matched? Or, would the xo points for the woofers and the tweeter in the CC be the same as the L/R, but then the midrange drivers would then just be on their own xo points in order to help with the dead spots?
For example, if the L/Rs have a xo point at 2kHz. Then can the xo at the woofers and the tweeter in the CC still be at 2kHz, while then the midrange drivers in the CC have a bandpass from like 800Hz to 4kHz? Or is that completely a bad idea?
For the F3, that does make a lot of sense how it needs to be low enough, so the sub becomes difficult to localize. So, is it just as easy as wanting to say “My F3 is at 80Hz”, or is there some math that can be done to find it? Or is the way to find the desired F3 in doing simulations? But even then, how would one determine the F3 from that? I noticed you got some F3 numbers from Unibox, I'm guessing it will give you a suggested F3.
I have downloaded and will be messing around with Unibox today to see how it works.
Thank you for the extra effort in the explanation of the max SPL for the system! That is very helpful and insightful. One question I have from that is; what do you mean by ‘baffle step compensation’? Is that like, if the tweeter were to be in-set a little bit for time alignment?
When you say, “a small sealed box of about 2-3L for each driver”. Are you talking about making sure there is that much gross volume for them all in the box, or that each driver in the CC should have their own small box inside the enclosure that is about 2-3L?
Also, while the room should definitely be accounted for, I unfortunately cannot account for the room size since my brother might be moving in the next year. But the Denon receiver does come with a small measurement mic and, while going through the right steps, will tune the room for you. Which is very helpful. This is not to say that the speaker position or anything else should be forgotten about though.
Yes! I have been reading that article, chipping away at it. While it is quite lengthy, it is very good and pretty helpful. Thank you for the reference!!
Just as an update. Right now I am testing the drivers, with help from the LDC. I am fortunate to have the tools I need for that and currently just finished my closed-box to now test for the speaker's Vas.
But I guess I am in a pickle. I do already have my drivers, yet I do want to do a proven design. I am still realizing new things and thinking about this a lot as I go. Though, I know that I already have made a few sets of speakers before and I’m ready to pull a lot of inspiration from proven designs and not try to ‘make the next great thing’. I already know a good amount, but I want to know more. That is why I will not 100% be going with a proven design. Because I want to push myself and challenge myself, which will help me learn. I’m not expecting greatness with this; I want to learn from my mistakes.
So, in conclusion, I would like to fully understand proven designs. About their volume, tuning frequency, volume, specific things they do for bracing or waveguides, their ports, and just everything. I want to learn all about them and lay it all out on the table. Then see what I would like to do with my design.
So, about the xo points for the CC, I have heard everywhere that the xo points of the L/R and the CC should always be the same to match the voicing. So, is it possible to have different xo points in the CC and the L/R, but still have the voicing matched? Or, would the xo points for the woofers and the tweeter in the CC be the same as the L/R, but then the midrange drivers would then just be on their own xo points in order to help with the dead spots?
For example, if the L/Rs have a xo point at 2kHz. Then can the xo at the woofers and the tweeter in the CC still be at 2kHz, while then the midrange drivers in the CC have a bandpass from like 800Hz to 4kHz? Or is that completely a bad idea?
For the F3, that does make a lot of sense how it needs to be low enough, so the sub becomes difficult to localize. So, is it just as easy as wanting to say “My F3 is at 80Hz”, or is there some math that can be done to find it? Or is the way to find the desired F3 in doing simulations? But even then, how would one determine the F3 from that? I noticed you got some F3 numbers from Unibox, I'm guessing it will give you a suggested F3.
I have downloaded and will be messing around with Unibox today to see how it works.
Thank you for the extra effort in the explanation of the max SPL for the system! That is very helpful and insightful. One question I have from that is; what do you mean by ‘baffle step compensation’? Is that like, if the tweeter were to be in-set a little bit for time alignment?
When you say, “a small sealed box of about 2-3L for each driver”. Are you talking about making sure there is that much gross volume for them all in the box, or that each driver in the CC should have their own small box inside the enclosure that is about 2-3L?
Also, while the room should definitely be accounted for, I unfortunately cannot account for the room size since my brother might be moving in the next year. But the Denon receiver does come with a small measurement mic and, while going through the right steps, will tune the room for you. Which is very helpful. This is not to say that the speaker position or anything else should be forgotten about though.
Yes! I have been reading that article, chipping away at it. While it is quite lengthy, it is very good and pretty helpful. Thank you for the reference!!
Just as an update. Right now I am testing the drivers, with help from the LDC. I am fortunate to have the tools I need for that and currently just finished my closed-box to now test for the speaker's Vas.
I'm going to try and keep this a little shorter this time.
Here are 2 more links to excellent proven design resources. Lots and lots of info about design and implementation and construction:
Zaph Audio
Troels Graveson
Your idea about the CC xo simply won't work. Not a good idea.
Some points about voicing.
One would think that voice matching just means getting the exact same FR from all the speakers but it's a little more complex than that. For eg, you might have a paper cone driver and a metal one with the exact same FR but they won't sound exactly the same because among other things they will have different harmonic distortion. Kind of like the same note (ie frequency) can be played by different instruments but each one will definitely sound different because of their harmonic structure.
As you read more about baffle diffraction hopefully you should figure out that even if you put all the same drivers and xo's in the L&R speakers as the CC, the front baffles are going to have totally different dimensions (usually) and so the FR won't actually be the same. To get decent voice matching, the CC xo's have to actually be a little different than the L&R. Doesn't hurt though if the xo point(s) are the same.
And lastly, you are leaving out the room. How each speaker interacts with its closest boundaries and objects will also change the perceived FR at the listening position. In this respect, it's almost not worth worrying about HT voice matching unless you use the exact same speaker (drivers, xo's and dimensions) in every position in the room and the room is a properly dedicated HT room that has been correctly treated acoustically.
For the rest of us rubes, as you mention HT receivers have a built in measuring and eq system that tries to correct for all the differences I just mentioned above anyways. So yes, if you've got a clean design slate to start off with, then sure try to match the front soundstage as closely as possible. But you are starting with a bunch of different drivers that you already bought and so don't sweat the small stuff - just do the best job you can to match FR's and then let the receiver correct for any discrepancies that might exist.
Re box tuning: it's all about each driver's TS parameters, although you do have some flexibility within those limitations. You've got the LDC. Read or re-read chapters 1 and 2 on closed and vented box alignments. Or read and re-read post #5 in the 'Building Speakers from Scratch' thread and then play with Unibox until the light bulb goes off. Input all the drivers you have chosen into the program and hopefully the numbers I used in my last post should start to make sense.
Re BSC (baffle step compensation): I've given you 3 links that deal with the topic. I don't know what else to say beyond you have to put in the time and do the reading to get it. And again play with one of the simulators until it makes sense and then play with it some more. Given your situation, I would design for the full 6dB of BSC for all your speakers and again, let the receiver do the corrections if and when they are necessary.
Just a correction: HT receivers don't tune the room, they simply eq the speakers to a certain target FR.
If you are trying to actually measure your drivers' TS parameters, nothing wrong there except it looks to me like you are trying to run before you can walk. Put the time in 1st to understand what to do with them (re box modeling) and also how to use some of the other software necessary to the design process. In the meantime, just use what the spec sheets have measured. For the drivers you have chosen and for your design purposes right now, I think that will be fine.
Just to clarify, it seems clear that to me that you need 1 of 2 things - you either need somebody to walk you through the design process or you need someone to basically design the speakers for you. Although I have done the former in the past, I don't have the time for that right now. It is possible though that I might be able to simulate some xo's for the drivers you've purchased. Chances are just using the spec sheets, they won't be perfect but chances are also very good that they will be perfectly adequate for what you are trying to achieve here. When did you plan to start making sawdust? Because if it's not soon, I guess a 3rd option is to take the time and do the reading and work necessary to acquire the knowledge and competency to do it yourself.
Here are 2 more links to excellent proven design resources. Lots and lots of info about design and implementation and construction:
Zaph Audio
Troels Graveson
Your idea about the CC xo simply won't work. Not a good idea.
Some points about voicing.
One would think that voice matching just means getting the exact same FR from all the speakers but it's a little more complex than that. For eg, you might have a paper cone driver and a metal one with the exact same FR but they won't sound exactly the same because among other things they will have different harmonic distortion. Kind of like the same note (ie frequency) can be played by different instruments but each one will definitely sound different because of their harmonic structure.
As you read more about baffle diffraction hopefully you should figure out that even if you put all the same drivers and xo's in the L&R speakers as the CC, the front baffles are going to have totally different dimensions (usually) and so the FR won't actually be the same. To get decent voice matching, the CC xo's have to actually be a little different than the L&R. Doesn't hurt though if the xo point(s) are the same.
And lastly, you are leaving out the room. How each speaker interacts with its closest boundaries and objects will also change the perceived FR at the listening position. In this respect, it's almost not worth worrying about HT voice matching unless you use the exact same speaker (drivers, xo's and dimensions) in every position in the room and the room is a properly dedicated HT room that has been correctly treated acoustically.
For the rest of us rubes, as you mention HT receivers have a built in measuring and eq system that tries to correct for all the differences I just mentioned above anyways. So yes, if you've got a clean design slate to start off with, then sure try to match the front soundstage as closely as possible. But you are starting with a bunch of different drivers that you already bought and so don't sweat the small stuff - just do the best job you can to match FR's and then let the receiver correct for any discrepancies that might exist.
Re box tuning: it's all about each driver's TS parameters, although you do have some flexibility within those limitations. You've got the LDC. Read or re-read chapters 1 and 2 on closed and vented box alignments. Or read and re-read post #5 in the 'Building Speakers from Scratch' thread and then play with Unibox until the light bulb goes off. Input all the drivers you have chosen into the program and hopefully the numbers I used in my last post should start to make sense.
Re BSC (baffle step compensation): I've given you 3 links that deal with the topic. I don't know what else to say beyond you have to put in the time and do the reading to get it. And again play with one of the simulators until it makes sense and then play with it some more. Given your situation, I would design for the full 6dB of BSC for all your speakers and again, let the receiver do the corrections if and when they are necessary.
Just a correction: HT receivers don't tune the room, they simply eq the speakers to a certain target FR.
If you are trying to actually measure your drivers' TS parameters, nothing wrong there except it looks to me like you are trying to run before you can walk. Put the time in 1st to understand what to do with them (re box modeling) and also how to use some of the other software necessary to the design process. In the meantime, just use what the spec sheets have measured. For the drivers you have chosen and for your design purposes right now, I think that will be fine.
Just to clarify, it seems clear that to me that you need 1 of 2 things - you either need somebody to walk you through the design process or you need someone to basically design the speakers for you. Although I have done the former in the past, I don't have the time for that right now. It is possible though that I might be able to simulate some xo's for the drivers you've purchased. Chances are just using the spec sheets, they won't be perfect but chances are also very good that they will be perfectly adequate for what you are trying to achieve here. When did you plan to start making sawdust? Because if it's not soon, I guess a 3rd option is to take the time and do the reading and work necessary to acquire the knowledge and competency to do it yourself.
There is a long thread on htguide.com for Denny Murphy Dayton TMWW. Thread includes amplifier suggestions. You will need to join the forum to view this info.
HTGuide Forum
