Hi,
If you haven't bought the drivers yet simply build a good well known
design and learn about the design details as you are building. Crossing
the tweeter too low causes distortion and very low overexcursion.
What sort of speaker do you want ?
rgds, sreten.
undefinition (see if nothing else, the excellent FAQs)
The Speaker Building Bible - Thread opened for edits/input. - Techtalk Speaker Building, Audio, Video, and Electronics Customer Discussion Forum From Parts-Express.com
Zaph|Audio
Zaph|Audio - ZA5 Speaker Designs with ZA14W08 woofer and Vifa DQ25SC16-04 tweeter
http://audio.claub.net/Simple Loudspeaker Design ver2.pdf
FRD Consortium tools guide
Designing Crossovers with Software Only
RJB Audio Projects
Jay's DIY Loudspeaker Projects
Speaker Design Works
HTGuide Forum - A Guide to HTguide.com Completed Speaker Designs.
A Speaker project
DIY Loudspeaker Projects Troels Gravesen
Humble Homemade Hifi
Quarter Wavelength Loudspeaker Design
The Frugal-Horns Site -- High Performance, Low Cost DIY Horn Designs
Linkwitz Lab - Loudspeaker Design
Music and Design
Great free SPICE Emulator : SPICE-Based Analog Simulation Program - TINA-TI - TI Tool Folder
If you haven't bought the drivers yet simply build a good well known
design and learn about the design details as you are building. Crossing
the tweeter too low causes distortion and very low overexcursion.
What sort of speaker do you want ?
rgds, sreten.
undefinition (see if nothing else, the excellent FAQs)
The Speaker Building Bible - Thread opened for edits/input. - Techtalk Speaker Building, Audio, Video, and Electronics Customer Discussion Forum From Parts-Express.com
Zaph|Audio
Zaph|Audio - ZA5 Speaker Designs with ZA14W08 woofer and Vifa DQ25SC16-04 tweeter
http://audio.claub.net/Simple Loudspeaker Design ver2.pdf
FRD Consortium tools guide
Designing Crossovers with Software Only
RJB Audio Projects
Jay's DIY Loudspeaker Projects
Speaker Design Works
HTGuide Forum - A Guide to HTguide.com Completed Speaker Designs.
A Speaker project
DIY Loudspeaker Projects Troels Gravesen
Humble Homemade Hifi
Quarter Wavelength Loudspeaker Design
The Frugal-Horns Site -- High Performance, Low Cost DIY Horn Designs
Linkwitz Lab - Loudspeaker Design
Music and Design
Great free SPICE Emulator : SPICE-Based Analog Simulation Program - TINA-TI - TI Tool Folder
Phase. What is phase?
You have to read to understand about phase. (google, there are also videos)
Think of it like the reverse of the sound wave.
So the wave front and the back of the wave or anti-phase give you a null. The consequence is that well guess... no output. For speakers/sound you always want to have them coherent, with no "interference" between two sound sources from different locations in space, like when they criss-cross.
Phase, what is phase?
1. Loudspeaker designer John Dunlavy: By the Numbers... | Stereophile.com
2. Phase, Time and Distortion in Loudspeakers
3. Pi Speaker Forum - Baffle spacing, phase angles and time alignment, revisited - Wayne Parham, May 14, 2003 at 00:56:30
You have to read to understand about phase. (google, there are also videos)
Think of it like the reverse of the sound wave.
So the wave front and the back of the wave or anti-phase give you a null. The consequence is that well guess... no output. For speakers/sound you always want to have them coherent, with no "interference" between two sound sources from different locations in space, like when they criss-cross.
Phase, what is phase?
1. Loudspeaker designer John Dunlavy: By the Numbers... | Stereophile.com
2. Phase, Time and Distortion in Loudspeakers
3. Pi Speaker Forum - Baffle spacing, phase angles and time alignment, revisited - Wayne Parham, May 14, 2003 at 00:56:30
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So I asked madisound to do a LEAP design to see what came back they advised against using the Seas H1224 because of "the limitations of a larger cone woofer being used well into the upper midrange." What do they mean? Can someone provide a link to the Zaphs crossover that was referred to earlier? I can't find it.
Rijaak,
Please, please go get a copy of Joe DeApollito's book on measuring speakers. I am sure there other primers out there. Read Zaph's WEB, Read Linkwitz's WEB. This is actually a very complex subject.
Designing crossovers is all about phase and driver interaction. 90% of the results is the crossover. You are jumping way too far ahead. "Flat" response is not exactly correct. Even if you are going to copy a crossover, take the time to understand what it is trying to do. Download and read the users manual to SoundEasy. You can learn a lot.
If you don't have it, download WinISD for a good start on cabinet design software. Don't guess. I recommend first projects to be sealed as they are more forgiving.
Where I am coming form is the WEB has a lot of information. Be careful which you pick. Go to the places where it is reliable. Sreten gave you a good list. This forum has some very very astute members. Pay attention. Do some homework. If for no other reason, crossover parts are getting very expensive so you want to have to re-do them as few times as possible!
Please, please go get a copy of Joe DeApollito's book on measuring speakers. I am sure there other primers out there. Read Zaph's WEB, Read Linkwitz's WEB. This is actually a very complex subject.
Designing crossovers is all about phase and driver interaction. 90% of the results is the crossover. You are jumping way too far ahead. "Flat" response is not exactly correct. Even if you are going to copy a crossover, take the time to understand what it is trying to do. Download and read the users manual to SoundEasy. You can learn a lot.
If you don't have it, download WinISD for a good start on cabinet design software. Don't guess. I recommend first projects to be sealed as they are more forgiving.
Where I am coming form is the WEB has a lot of information. Be careful which you pick. Go to the places where it is reliable. Sreten gave you a good list. This forum has some very very astute members. Pay attention. Do some homework. If for no other reason, crossover parts are getting very expensive so you want to have to re-do them as few times as possible!
First, explain the audience (if you insist) why you are certain about your decision in choosing your drivers to make your first pair of speakers. "What does computers has to do with it..."
Sorry to say I don't admire members that instead of asking for questions about what their drivers should be (or kits) ask a lot of questions and know nothing.
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Dad was an electrical engineer with a hobby in audio design. I made the mistake of permanently mounting tweeters into an existing cab without considering the cross over or woofers installed in it. So I thought it would be a fun hobby to try to reenginer the speakers with new woofers since the old ones seem to be incompatable with the new tweeters (my understanding is that you can attenuate tweeters with l pads, but never want to attenuate woofers). Sorry if Ive offended in my attempts to teach myself and examine possible solutions.
As for the seas woofers, Im trying to work with them because the computed port size and ideal cab volume would require very little modification to the existing cabs.
As for the seas woofers, Im trying to work with them because the computed port size and ideal cab volume would require very little modification to the existing cabs.
No problem. Now I see. Many more members can help you now that they know the problem with the design concept.
My fair share of sympathy to you. The problem with "asking-questions-threads" is that they never go anywhere because their members are always in doubt plus it sprawls like a virus with a variety of empty answers. Not in this case of course. Hope you liked the phase readings.
Questions?
What size of speakers you have (internal volume).
What speaker drivers you already have (or bought).
What type of crossover you r using (maybe good for parts/components).
You can post pictures if that helps. The type of information how you are going to use your speakers, distance, all is going to help in making decisions.
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The internal volume of the cabinet is about 0.8 cu ft. But there is polyfill in it. My guess is that brings its effective internal volume to about 0.9 cu ft. There are two cutouts for woofers about 6" diameter. The relative position of the cutout centers, if the center of the tweeter is at (0,0) meters is: upper woofer (0.14,-0.038), lower woofer (0.14,-0.254). The tweeter is aimed at a 45 degree angle towards the center of the room, on an angled side of the cabinet. There are two flared ports in the cabinet located on the same angle side as the tweeter. The relative positions of the centers of the ports to the center of the tweeter are (0,-0.1397) and (0,-0.2794). The flared ports are about 1.75" diameter (at the opening, not the smallest diameter) and 3" long.
I measured the original drivers using DATS. They are 6.5" paper cone woofers that have a diameter of 5" when measuring the cone and half the rubber surround. I think they're rated at 4 or 6 ohms resistance. The data for them from DATS is: Fs=85.46, Qts=0.498, Qes=0.592, Qms=6.179, Vas=0.2335. By using this site (Speaker Box Calculations) and plugging in my data from DATS, I determined ideal box volume for one woofer to be Vb=0.4679 and ideal frequency to be Fb=68.8935 hz. The original crossover (ImageShack® - Online Photo and Video Hosting) seems to be some sort of 2.5 way which rolls off the mid-range frequencies of the lower woofer. Since both woofers seemingly function at the lower frequencies, the Vb for the two woofers together would be Vb=0.4679*2=.92 cu ft. This seems to confirm my assumptions about the effective volume of the cabinet with the polyfill. By plugging in Fb=68hz, Vb=0.9 cu ft, 2 ports, and port diameter 1.75" on this site (Products Menu) the flared port length is 2.83, which seemingly confirms my methods for measuring port diameter. In order to accurately determine the response curve of these woofers, I'd need to buy a kit, but I estimate their sensitivity to be around 94 db, well above that of the new tweeters, making them ( I think) not viable for application in the new system.
The new tweeters which are installed in the cabinets are the Vifa XT25SC90-04 which have different response curves than the regular Vifa XT25s used in the projects referred to by posters earlier in this thread. Here is a link to their data as provided by madisound (Madisound Speaker Store).
The Seas H1224 (Madisound Speaker Store) seem like they would work well as replacement woofers because they are the right size and, when hooked up parallel in a 2-way crossover, the sensitivity would not have to be attenuated to mesh well with the tweeters. In addition, when I plugged the data provided by madisound into (Speaker Box Calculations), it seems like the ideal Vb for the two woofers together would be around Vb=0.9 cu ft and require little modification (maybe a little extra polyfill to compensate for the added displacement of a better crossover). Using ideal Vb=0.9, ideal Fb=47.1325 (determined in Speaker Box Calculations), and 1 port with diameter 1.75", the yielded flared port length from (Products Menu) is 2.96". So it seems like all I would have to do is install the Seas, add a little polyfill, plug up one port with a rubber stopper and some glue (probably the lower port?), and redesign the crossover.
The crossover design is proving problematic because I only have a basic understanding of electronics. As far how I use my speakers and their position relative to the listener: I have two pairs of speakers, one in front on either side of my LCD screen and one wall-mounted on the opposing side of the room (they are almost directly across from the ones in front of the room). The two in front are on non-functional speakers as pedestals and the ones in the rear are mounted 3'11" above the ones in front and aimed very slightly downwards. When I play video games the speakers are surround sound, the listening position is about 1.5 meters from each speaker and directly in the middle (in front of the lcd). When using home theatre the speakers are also surround sound and the most common listening positions are underneath the left rear speaker or between the right front and right rear speakers. I CARE MOST ABOUT SOUND QUALITY when I'm playing my music, during which time both front and rear speakers are stereo to fill the room and listening position is anywhere throughout the room.
I measured the original drivers using DATS. They are 6.5" paper cone woofers that have a diameter of 5" when measuring the cone and half the rubber surround. I think they're rated at 4 or 6 ohms resistance. The data for them from DATS is: Fs=85.46, Qts=0.498, Qes=0.592, Qms=6.179, Vas=0.2335. By using this site (Speaker Box Calculations) and plugging in my data from DATS, I determined ideal box volume for one woofer to be Vb=0.4679 and ideal frequency to be Fb=68.8935 hz. The original crossover (ImageShack® - Online Photo and Video Hosting) seems to be some sort of 2.5 way which rolls off the mid-range frequencies of the lower woofer. Since both woofers seemingly function at the lower frequencies, the Vb for the two woofers together would be Vb=0.4679*2=.92 cu ft. This seems to confirm my assumptions about the effective volume of the cabinet with the polyfill. By plugging in Fb=68hz, Vb=0.9 cu ft, 2 ports, and port diameter 1.75" on this site (Products Menu) the flared port length is 2.83, which seemingly confirms my methods for measuring port diameter. In order to accurately determine the response curve of these woofers, I'd need to buy a kit, but I estimate their sensitivity to be around 94 db, well above that of the new tweeters, making them ( I think) not viable for application in the new system.
The new tweeters which are installed in the cabinets are the Vifa XT25SC90-04 which have different response curves than the regular Vifa XT25s used in the projects referred to by posters earlier in this thread. Here is a link to their data as provided by madisound (Madisound Speaker Store).
The Seas H1224 (Madisound Speaker Store) seem like they would work well as replacement woofers because they are the right size and, when hooked up parallel in a 2-way crossover, the sensitivity would not have to be attenuated to mesh well with the tweeters. In addition, when I plugged the data provided by madisound into (Speaker Box Calculations), it seems like the ideal Vb for the two woofers together would be around Vb=0.9 cu ft and require little modification (maybe a little extra polyfill to compensate for the added displacement of a better crossover). Using ideal Vb=0.9, ideal Fb=47.1325 (determined in Speaker Box Calculations), and 1 port with diameter 1.75", the yielded flared port length from (Products Menu) is 2.96". So it seems like all I would have to do is install the Seas, add a little polyfill, plug up one port with a rubber stopper and some glue (probably the lower port?), and redesign the crossover.
The crossover design is proving problematic because I only have a basic understanding of electronics. As far how I use my speakers and their position relative to the listener: I have two pairs of speakers, one in front on either side of my LCD screen and one wall-mounted on the opposing side of the room (they are almost directly across from the ones in front of the room). The two in front are on non-functional speakers as pedestals and the ones in the rear are mounted 3'11" above the ones in front and aimed very slightly downwards. When I play video games the speakers are surround sound, the listening position is about 1.5 meters from each speaker and directly in the middle (in front of the lcd). When using home theatre the speakers are also surround sound and the most common listening positions are underneath the left rear speaker or between the right front and right rear speakers. I CARE MOST ABOUT SOUND QUALITY when I'm playing my music, during which time both front and rear speakers are stereo to fill the room and listening position is anywhere throughout the room.
Your speakers will became directional because of diferent tweeters you are using instead of original cones.
Now with that tweeter you have you will need a crossover.
Vifa XT25TG30-04 1" Ring Radiator Tweeter
WWT second order crossover
Use 2 woofers adequate for that size of enclosure.
Eton 7-200/A8 Symphony
Adjust. Probably you will have problems in directivity and output amplitude between the woofers and the tweeter but that's the best I can do.
If you mess to much with a concept (original bose 4001) better to start from scratch with a new kit and enclosure. Sorry not being able to help you more.
Another variant for that enclosure (internal volume) is the
SEAS Prestige P18RNX/P (H1350) 7"
Have a nice diy.
Now with that tweeter you have you will need a crossover.
Vifa XT25TG30-04 1" Ring Radiator Tweeter
WWT second order crossover
Use 2 woofers adequate for that size of enclosure.
Eton 7-200/A8 Symphony
Adjust. Probably you will have problems in directivity and output amplitude between the woofers and the tweeter but that's the best I can do.
If you mess to much with a concept (original bose 4001) better to start from scratch with a new kit and enclosure. Sorry not being able to help you more.
Another variant for that enclosure (internal volume) is the
SEAS Prestige P18RNX/P (H1350) 7"
Have a nice diy.
Your speakers will became directional because of diferent tweeters you are using instead of original cones.
Now with that tweeter you have you will need a crossover.
Vifa XT25TG30-04 1" Ring Radiator Tweeter
WWT second order crossover
Use 2 woofers adequate for that size of enclosure.
Eton 7-200/A8 Symphony
Adjust. Probably you will have problems in directivity and output amplitude between the woofers and the tweeter but that's the best I can do.
If you mess to much with a concept (original bose 4001) better to start from scratch with a new kit and enclosure. Sorry not being able to help you more.
Another variant for that enclosure (internal volume) is the
SEAS Prestige P18RNX/P (H1350) 7"
Have a nice diy.
__________________
Most of John Krutke's experience with metal woofers indicates that this should be a fourth-order crossover. Can you upload the response curve that goes with it? I think there needs to be a notch filter for the distortion from the woofers.
Now with that tweeter you have you will need a crossover.
Vifa XT25TG30-04 1" Ring Radiator Tweeter
WWT second order crossover
Use 2 woofers adequate for that size of enclosure.
Eton 7-200/A8 Symphony
Adjust. Probably you will have problems in directivity and output amplitude between the woofers and the tweeter but that's the best I can do.
If you mess to much with a concept (original bose 4001) better to start from scratch with a new kit and enclosure. Sorry not being able to help you more.
Another variant for that enclosure (internal volume) is the
SEAS Prestige P18RNX/P (H1350) 7"
Have a nice diy.
__________________
Most of John Krutke's experience with metal woofers indicates that this should be a fourth-order crossover. Can you upload the response curve that goes with it? I think there needs to be a notch filter for the distortion from the woofers.
So Inductor, this is the output from PCD for your leap design: ImageShack® - Online Photo and Video Hosting
pretty heinous. I think it could be done better. I'm having difficulty using the phase software on my computer and figuring out how to incorporate the baffle design output. If I upload screenshots of a new design, can you guys help me to account for this?
pretty heinous. I think it could be done better. I'm having difficulty using the phase software on my computer and figuring out how to incorporate the baffle design output. If I upload screenshots of a new design, can you guys help me to account for this?
That's not the woofers I considered above.
"You bring water to the sea" if you're insisting in your own endeavors.
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