Alright, Today I thought I would start to design my enclosures, but I am having a lot of trouble. I've tried various software and online calculators, but all of them have many differant paramateres for the speaker that I do not know.
I have:
1 10" MTX sub, 8 Ohm, 125RMS
2 4.75" (12cm), Panasonic, 6 Ohm, 45RMS
2 2.375' (6cm), Panasonic, 6 Ohm, 45RMS (a "supertwetter" piezoelement is attached to this tweeter which I hope to use"
How would I go about beginning to design this?
I am thinking of a ported enclosure for the sub.
I would like indidvidual boxes for each speaker.
I have:
1 10" MTX sub, 8 Ohm, 125RMS
2 4.75" (12cm), Panasonic, 6 Ohm, 45RMS
2 2.375' (6cm), Panasonic, 6 Ohm, 45RMS (a "supertwetter" piezoelement is attached to this tweeter which I hope to use"
How would I go about beginning to design this?
I am thinking of a ported enclosure for the sub.
I would like indidvidual boxes for each speaker.
book Learnin'
I can only tell you how I started:
Soon after discovering I had a sincere interest in learning how these things
work ---->> Loudspeakers,
I bought a book from Radio Shack, and soon there after bought six more books and read them cover-to-cover.
There were no sims, and one had to wind one's own coils, aka inductors.
Obviously, it was many years ago (41).
I can only tell you how I started:
Soon after discovering I had a sincere interest in learning how these things
work ---->> Loudspeakers,
I bought a book from Radio Shack, and soon there after bought six more books and read them cover-to-cover.
There were no sims, and one had to wind one's own coils, aka inductors.
Obviously, it was many years ago (41).
Where 'just a box' leads to ? I wouldn't care less about the box ...just make
something like an U-frame for the woofer.
Much work would be to make the three speakers - well, two, if one is considered like an extra ( the stw )- work together.
The 'learning curve' would then ask to follow many conjectures from simple
speaker parameters to driver intercenter distance, to polar patterns and
interpolations with crossover architecture which may take years to know deeply.
What's good with the old school about making your own coils ?
Well, I'd start with it, and make a 7-8 mH bobbin 😀🙄
something like an U-frame for the woofer.
Much work would be to make the three speakers - well, two, if one is considered like an extra ( the stw )- work together.
The 'learning curve' would then ask to follow many conjectures from simple
speaker parameters to driver intercenter distance, to polar patterns and
interpolations with crossover architecture which may take years to know deeply.
What's good with the old school about making your own coils ?
Well, I'd start with it, and make a 7-8 mH bobbin 😀🙄
Has come a very long way
Nothing really "good' about the old way- winding coils. In my opinion though, book reading will never be replaced. Back in the so called "day" building one's own speakers was not as popular as it is today. The only thing we had was McGee Radio/Electronics and Radio Shack. Lafayette came along soon thereafter with real-true low resonance woofers. I don't remember the exact time line, but Meniscus, Madisound, and Parts Express have changed the speaker building world. There were also a few smaller scaled mail-order outfits.
I knew some folks who started in Connecticut and ended in Colorado:
"Transcendental Audio".....also the folks in California who did the Corner horns, but I'm sorry I forget their name. Might have been "Speaker Lab" or I might be mixing them up with another outfit.
You young speaker builders don't know how good you have it !!
Nothing really "good' about the old way- winding coils. In my opinion though, book reading will never be replaced. Back in the so called "day" building one's own speakers was not as popular as it is today. The only thing we had was McGee Radio/Electronics and Radio Shack. Lafayette came along soon thereafter with real-true low resonance woofers. I don't remember the exact time line, but Meniscus, Madisound, and Parts Express have changed the speaker building world. There were also a few smaller scaled mail-order outfits.
I knew some folks who started in Connecticut and ended in Colorado:
"Transcendental Audio".....also the folks in California who did the Corner horns, but I'm sorry I forget their name. Might have been "Speaker Lab" or I might be mixing them up with another outfit.
You young speaker builders don't know how good you have it !!
Thiel & Small made it far easier by giving us some true science & formulas to work with...instead of the hit & miss scenario of old.
Simulations, the computer , social media has made it far far easier.
Let us focus on the task at hand, the OP has these drivers .....lets try to dig up some TS parameters....instead of doing it # Old School#......
If we cant get TSs, best to do some experiments to appx some specs.
Whos with me??? I will start with the MTX sub....... To the original poster....What are the model numbers written on the back of your drivers.....We need them as some makes of drivers change models, almost yearly or less.
____________________________________________________________Rick...
Simulations, the computer , social media has made it far far easier.
Let us focus on the task at hand, the OP has these drivers .....lets try to dig up some TS parameters....instead of doing it # Old School#......
If we cant get TSs, best to do some experiments to appx some specs.
Whos with me??? I will start with the MTX sub....... To the original poster....What are the model numbers written on the back of your drivers.....We need them as some makes of drivers change models, almost yearly or less.
____________________________________________________________Rick...
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The 10" Mtx: Near the magnet coils, its says "1 OMC1187 8
Ohm" below that it says "557 9818" On the back of the cones is stamped
"3CF361" and below that is "158"
I emailed MTX about and they said it came from a older 1995 dual road thumder enclosure. They also said it was 8 ohm 125WRMS. The original info is from a pamplet (its on p18)
Link they sent me: http://2004.mtxaudio.eu/IMG/pdf/Leaflet_MTX_2000_us.pdf
The other two came from a panasonic speaker set part number SB-AK300.
It was originally with a stereo system whose part number is SC-AK300.
Link to user manual: http://service.us.panasonic.com/OPERMANPDF/SCAK500.PDF
P. 31 has the most useful data.
As far as t/s parameters. I cant find any. I've read up on how to manually figure them out, but my multimeter doesn't measue down to mV for AC. Could I figure it using a computer with the mic port and some software.
I've taken a look at WinISD, but as I've already said I don't have the t/s parameters.
Thank YOU.
Ohm" below that it says "557 9818" On the back of the cones is stamped
"3CF361" and below that is "158"
I emailed MTX about and they said it came from a older 1995 dual road thumder enclosure. They also said it was 8 ohm 125WRMS. The original info is from a pamplet (its on p18)
Link they sent me: http://2004.mtxaudio.eu/IMG/pdf/Leaflet_MTX_2000_us.pdf
The other two came from a panasonic speaker set part number SB-AK300.
It was originally with a stereo system whose part number is SC-AK300.
Link to user manual: http://service.us.panasonic.com/OPERMANPDF/SCAK500.PDF
P. 31 has the most useful data.
As far as t/s parameters. I cant find any. I've read up on how to manually figure them out, but my multimeter doesn't measue down to mV for AC. Could I figure it using a computer with the mic port and some software.
I've taken a look at WinISD, but as I've already said I don't have the t/s parameters.
Thank YOU.
OK, after much reading on the MTX link you provided, I came up with this.
The site has those dual 10" enclosures to accept the MTX drivers...now they seemed not to differentiate the 4000, 6000, 8000 series "plugged into" those enclosures. Do you have the 4000 series with the black cones? The 6000 and 8000 series have the ribbed silver cones. After trying to dechipher the enclosures, shapes & enclosure volumes, taking into consideration the 70 degree angles and all, I came up with 1.9368 cubic feet per driver...
Build yourself a sealed enclosure with one-inch thick MDF (Medium density fibreboard) at 14 inches by 17 inches by 20 inches.
Why not a ported system....well, the ported enclosure really demands very accurate T/S parameters & we don't got em! I've found a lot of Car subs will design drivers with a "split personality"...drivers that are suitable for sealed or ported, often times not too successful in either......it's just that it is designed for the novice builder who won't or can't crunch formulas to design it hyper accurately. This is the best I could come up with the available info....I do so wish you would have a second one so we can build a proper pair of enclosures. This one enclosure would be best run with a sub-woofer "plate-amp"....the type of amp that is "built-in" to the enclosure.
______________________________________________Rick.........
The site has those dual 10" enclosures to accept the MTX drivers...now they seemed not to differentiate the 4000, 6000, 8000 series "plugged into" those enclosures. Do you have the 4000 series with the black cones? The 6000 and 8000 series have the ribbed silver cones. After trying to dechipher the enclosures, shapes & enclosure volumes, taking into consideration the 70 degree angles and all, I came up with 1.9368 cubic feet per driver...
Build yourself a sealed enclosure with one-inch thick MDF (Medium density fibreboard) at 14 inches by 17 inches by 20 inches.
Why not a ported system....well, the ported enclosure really demands very accurate T/S parameters & we don't got em! I've found a lot of Car subs will design drivers with a "split personality"...drivers that are suitable for sealed or ported, often times not too successful in either......it's just that it is designed for the novice builder who won't or can't crunch formulas to design it hyper accurately. This is the best I could come up with the available info....I do so wish you would have a second one so we can build a proper pair of enclosures. This one enclosure would be best run with a sub-woofer "plate-amp"....the type of amp that is "built-in" to the enclosure.
______________________________________________Rick.........
Well, I am more then willing to crunch numbers, as I am not planning on building this project because I need a speaker system. I want to learn about speakers and analog circuits. Therefor crunching numbers would increase my knowledge and the overall quality of my project.
I realize that with the drivers I have, my system will not sound like 1000$ speakers, because they are not. Therefor I have come to the conclusion that by performing t/s calculations I could get fairly acurate parameters in order to build sufficient enclosures (and increase in understanding and knowledge)
I have done a fair amount of research, and think I will follow this guide: epanorama.net/Speaker element Thiele-Small parameters
My only problems are I need a 8 Ohm resistor (If I was testing a 6ohm driver would I need a 6 Ohm resistor?)
And I need a signal generator and a voltmeter that measures mV of AC (my multimeter goes down to .1V); could I used a pc based oscililoscope with the mic in for this?
I realize that with the drivers I have, my system will not sound like 1000$ speakers, because they are not. Therefor I have come to the conclusion that by performing t/s calculations I could get fairly acurate parameters in order to build sufficient enclosures (and increase in understanding and knowledge)
I have done a fair amount of research, and think I will follow this guide: epanorama.net/Speaker element Thiele-Small parameters
My only problems are I need a 8 Ohm resistor (If I was testing a 6ohm driver would I need a 6 Ohm resistor?)
And I need a signal generator and a voltmeter that measures mV of AC (my multimeter goes down to .1V); could I used a pc based oscililoscope with the mic in for this?
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Old school
Your leaning towards doing things very old school, and that might be frowned upon around here. Epanorama is much more complicated than the method I use. I use a fixed volume test box for measuring Vas. The testing cicuit is not that complicated, either...howevere, I am not set up for impedance measurements; epan is, and imp measurements are important in finding resonances (as in disturbances) of any speaker system.
Finding an audio frequency generator is challenging, but not impossible. The thing is, the cost for all the things you need are much higher than what Parts express sells as a "woofer tester". Having said all that, I do applaude your desire to learn these things.
Depending upon the size of the city you live in, you might find some kindly older gentlemen who work in electronic repair shops to help you out.
Your leaning towards doing things very old school, and that might be frowned upon around here. Epanorama is much more complicated than the method I use. I use a fixed volume test box for measuring Vas. The testing cicuit is not that complicated, either...howevere, I am not set up for impedance measurements; epan is, and imp measurements are important in finding resonances (as in disturbances) of any speaker system.
Finding an audio frequency generator is challenging, but not impossible. The thing is, the cost for all the things you need are much higher than what Parts express sells as a "woofer tester". Having said all that, I do applaude your desire to learn these things.
Depending upon the size of the city you live in, you might find some kindly older gentlemen who work in electronic repair shops to help you out.
Like that link you found....I have a pair of Pioneer "Four-way" 6X9s....{ Seems we tend to get a lot of auto audio stuff?} I had no TS parameters either for these drivers....& the four-way was a joke. It had those silly tiny peizo elements the size of a green pea. I wound up doing exactly what your anticipating..testing drivers for TS parameters. The 6X9s? just as I had guessed an Fs of 60 Hz, a Qts of 1.06 ....rather underdamped.
Thanks for all the replies, will definitly check out the ARTA software.
Thanks again; hopefully while have some specs shortly.
Thanks again; hopefully while have some specs shortly.
Alright, I have taken a look at LIMP and have a few questions;
I have a line out and a headphone jack on my computer, I tried it with a speaker and both work but, oddly the headpone out seems louder. LIMP will generate a signal through the headphone out, so I am assuming it's alright to use that. Refer to this diagram p8: http://www.artalabs.hr/download/LIMP-user-manual.pdf
I have to also find a 3.5mm chord/ old headphones and get a 100 Ohm resistor so it might be a little while before I get going.
Thank you
I have a line out and a headphone jack on my computer, I tried it with a speaker and both work but, oddly the headpone out seems louder. LIMP will generate a signal through the headphone out, so I am assuming it's alright to use that. Refer to this diagram p8: http://www.artalabs.hr/download/LIMP-user-manual.pdf
I have to also find a 3.5mm chord/ old headphones and get a 100 Ohm resistor so it might be a little while before I get going.
Thank you
I have one question. When LIMP asks for the resistance under analyze speaker parameters, does it want the nominal resistance, or the measured DC resistance?
Success...maybe.
I ran some tests using LIMP and here are the results:
MTX 10" Woofer:
Fs = 25.91 Hz
Re = 6.10 0hms[dc]
Le = 3393.21uH
L2 = 10648.43 uH
R2 = 5.03 ohms
Qt = 0.33
Qes = 0.38
Qms = 2.26
Mms = 1779.22 grams
Rms = 128.114929 kg/s
Cms = 0.000021 m/N
Vas = 3.93 liters
Sd = 363.05 cm^s
Bl = 68.148651 Tm
ETA = 0.02%
Lp(2.83V/1m) = 75.65 dB
Closed Box Method:
Box volume = 25.81 liters
Diameter 21.50 cm
12cm Mid
Fs = 78.15 Hz
Re = 5.40 ohms[dc]
Le = 210.90 uH
L2 = 776.71 71
R2 = 3.90 ohms
Qt = 1.36
Qes = 1.97
Qms = 4.40
Mms = 17.84 grams
Rms = 1.992077 kg/s
Cms = 0.000232 m/N
Vas = 4.18 liters
Sd = 113.10 cm^2
Bl = 4.904656 Tm
ETA = 0.10%
Lp(2.83V/1m) = 83.70 dB
Closed Box Method:
Box volume = 13.37 liters
Diameter 12.00 cm
Tweeter:
The Tweeter has a completely closed back so I ma assuming it does not matter what size/shape enclosure I put it in.
It seems to me that Vas is quite low, my output was quite low (I used my headphone jack out which was louder than the line out). So my 2 questions are:
1. Does Vas seem right?
2. Do all the other parameters seem practical?
I will attach the schematic that I used for my "jig".
I ran some tests using LIMP and here are the results:
MTX 10" Woofer:
Fs = 25.91 Hz
Re = 6.10 0hms[dc]
Le = 3393.21uH
L2 = 10648.43 uH
R2 = 5.03 ohms
Qt = 0.33
Qes = 0.38
Qms = 2.26
Mms = 1779.22 grams
Rms = 128.114929 kg/s
Cms = 0.000021 m/N
Vas = 3.93 liters
Sd = 363.05 cm^s
Bl = 68.148651 Tm
ETA = 0.02%
Lp(2.83V/1m) = 75.65 dB
Closed Box Method:
Box volume = 25.81 liters
Diameter 21.50 cm
12cm Mid
Fs = 78.15 Hz
Re = 5.40 ohms[dc]
Le = 210.90 uH
L2 = 776.71 71
R2 = 3.90 ohms
Qt = 1.36
Qes = 1.97
Qms = 4.40
Mms = 17.84 grams
Rms = 1.992077 kg/s
Cms = 0.000232 m/N
Vas = 4.18 liters
Sd = 113.10 cm^2
Bl = 4.904656 Tm
ETA = 0.10%
Lp(2.83V/1m) = 83.70 dB
Closed Box Method:
Box volume = 13.37 liters
Diameter 12.00 cm
Tweeter:
The Tweeter has a completely closed back so I ma assuming it does not matter what size/shape enclosure I put it in.
It seems to me that Vas is quite low, my output was quite low (I used my headphone jack out which was louder than the line out). So my 2 questions are:
1. Does Vas seem right?
2. Do all the other parameters seem practical?
I will attach the schematic that I used for my "jig".
Attachments
Success..I Think
I redid all my measurements with much greater care and attention to detail. My new t/s parameters sound reasonable, but I have zero experience or expertise.
10" MTX Sub
Parameter, Value, Dim
Fs, 24.89, Hz
Re, 6.05, ohms[dc]
Le, 1521.84, uH
L2, 9458.86, uH
R2, 25.60, ohms
Qt, 0.18, -
Qes, 0.21, -
Qms, 1.41, -
Mms, 1007.34, grams
Rms, 111.563965, kg/s
Cms, 0.000041, m/N
Vas, 13.74, liters
Sd, 490.87, cm^2
Bl, 67.310112, Tm
ETA, 0.10, %
Lp(2.83V/1m), 83.18, dB
12cm Mid
Fs = 80.92 Hz
Re = 5.40 ohms[dc]
Le = 219.34 uH
L2 = 779.95 uH
R2 = 3.43 ohms
Qt = 1.16
Qes = 1.74
Qms = 3.46
Mms = 11.78 grams
Rms = 1.732979 kgs
Cms = 0.000328 mN
Vas = 5.90 liters
Sd= 113.10 cm^2
Bl = 4.309291 Tm
ETA = 0.17 %
Lp(2.83V1m) = 86.18 dB
Closed Box Method
Box volume = 13.37 liters
Diameter= 12.00 cm
I redid all my measurements with much greater care and attention to detail. My new t/s parameters sound reasonable, but I have zero experience or expertise.
10" MTX Sub
Parameter, Value, Dim
Fs, 24.89, Hz
Re, 6.05, ohms[dc]
Le, 1521.84, uH
L2, 9458.86, uH
R2, 25.60, ohms
Qt, 0.18, -
Qes, 0.21, -
Qms, 1.41, -
Mms, 1007.34, grams
Rms, 111.563965, kg/s
Cms, 0.000041, m/N
Vas, 13.74, liters
Sd, 490.87, cm^2
Bl, 67.310112, Tm
ETA, 0.10, %
Lp(2.83V/1m), 83.18, dB
12cm Mid
Fs = 80.92 Hz
Re = 5.40 ohms[dc]
Le = 219.34 uH
L2 = 779.95 uH
R2 = 3.43 ohms
Qt = 1.16
Qes = 1.74
Qms = 3.46
Mms = 11.78 grams
Rms = 1.732979 kgs
Cms = 0.000328 mN
Vas = 5.90 liters
Sd= 113.10 cm^2
Bl = 4.309291 Tm
ETA = 0.17 %
Lp(2.83V1m) = 86.18 dB
Closed Box Method
Box volume = 13.37 liters
Diameter= 12.00 cm
It's very important to measure the diameter of the diaphragm as precisely as possible. The right point to measure is exacly in the middle of the surround.
Typical values for a 10" woofer are:
Sd = 340 cm^2
Mms = 25 - 80 g
Bl = 7 - 15 N/A
Typical values for a 12 cm midrange are:
Sd = 55 cm^2
Mms = 4 - 7 g
Bl = 3.5 - 7 N/A
Typical values for a 10" woofer are:
Sd = 340 cm^2
Mms = 25 - 80 g
Bl = 7 - 15 N/A
Typical values for a 12 cm midrange are:
Sd = 55 cm^2
Mms = 4 - 7 g
Bl = 3.5 - 7 N/A
Sorry for my noobness, but what classifies the surround.
I tried measuring from the edge of the cone to the edge of the cone and got 18.5
which gave me: (for the 10")
Mms = 302.06 grams
Sd= 268.80 cm^2
Bl = 36.858730 Tm
Bl and Mms are still very much higher then typical.
I tried measuring from the edge of the cone to the edge of the cone and got 18.5
which gave me: (for the 10")
Mms = 302.06 grams
Sd= 268.80 cm^2
Bl = 36.858730 Tm
Bl and Mms are still very much higher then typical.
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