Hello dear folks,
does one of the forum members have an idea or a clue if there is such a cabinet for the Mark Audio Alpair 12 P gen. 2 - or in what context these two TL designs needs / has to be modified?
For MA Alpair 12:
http://frugal-phile.com/boxlib/woden/Aln-0v82-map-281209.pdf
for the MA CHR 120 driver:
https://www.kjfaudio.com/wp-content/uploads/2020/04/CHR-120-twin-pipe.pdf
or another example:
https://www.dagogo.com/feastrex-makoto-loudspeaker-system-review/2/
The frugal horn “Joan” or the “Super Pensil” are eliminated from the outset due to their large footprint and the “Avebury” for the 12 P due to its “Empire State “ sky scraping style. To scale a appropriate footprint I prefer a maximum depth of 35cm with a maximum width of 28cm and a maximum hight of 150 cm should’nt be a “huge” Problem.
Even a folded ML - TQWT for the MA 12.2 P with this footprint and a line length above 200cm would fit.
Many thanks in advance for all of your suggestions and tips!
Kind regards
Stefan
does one of the forum members have an idea or a clue if there is such a cabinet for the Mark Audio Alpair 12 P gen. 2 - or in what context these two TL designs needs / has to be modified?
For MA Alpair 12:
http://frugal-phile.com/boxlib/woden/Aln-0v82-map-281209.pdf
for the MA CHR 120 driver:
https://www.kjfaudio.com/wp-content/uploads/2020/04/CHR-120-twin-pipe.pdf
or another example:
https://www.dagogo.com/feastrex-makoto-loudspeaker-system-review/2/
The frugal horn “Joan” or the “Super Pensil” are eliminated from the outset due to their large footprint and the “Avebury” for the 12 P due to its “Empire State “ sky scraping style. To scale a appropriate footprint I prefer a maximum depth of 35cm with a maximum width of 28cm and a maximum hight of 150 cm should’nt be a “huge” Problem.
Even a folded ML - TQWT for the MA 12.2 P with this footprint and a line length above 200cm would fit.
Many thanks in advance for all of your suggestions and tips!
Kind regards
Stefan
First point, A12p is a 2nd generation A12 but a first gen paper cone.
I have drawn many boxes for A12p.
Indeed the Feastrex (not very good IME) does seem to be stufffed into one of Scott’s pipe. I see some work need sbe dne on the drawing (it is pinched from another design, with CHR120 numbers subbed in. I expect A12p would need a different pipe, it has a much smaller Vas, same with the pipe for the A12, it will be closer but possibly too small.
If you want to do a pipe like those you may have to get Scott to do a custom design for you.
dave
I have drawn many boxes for A12p.
Indeed the Feastrex (not very good IME) does seem to be stufffed into one of Scott’s pipe. I see some work need sbe dne on the drawing (it is pinched from another design, with CHR120 numbers subbed in. I expect A12p would need a different pipe, it has a much smaller Vas, same with the pipe for the A12, it will be closer but possibly too small.
If you want to do a pipe like those you may have to get Scott to do a custom design for you.
dave
Hello dear folks,
does one of the group members have an idea or a clue. if there is such a cabinet for the Mark Audio Alpair 12 P gen. 2 - are these two cabinets TL designs(?) or are they really backloaded horns? And how have they to be modified for a MA 12 p Gen. 2 driver? So I calculated a bit!?
For MA Alpair 12
Revc = 7 Ohm
F0 = 46 Hz
Qms = 1,45
Qes = 0,42
Qts = 0,33
Vas = 22,00 Liter
Sd = 143 cm²
BL = 8,75 Tm
Le = 0,06 mH
Xmax = 12 mm
http://frugal-phile.com/boxlib/woden/Aln-0v82-map-281209.pdf
S d = 143 cm²
S 0 = 246, 77 qcm = 38,25 square inch
S l = 349,54 qcm = 54,19 square inch
Sl / S 0 ratio = 1,42
Loudspeaker offset ( from S 0) = 19,37cm = 7,625 inch
Length of the (middle) line = 241,51 cm = 95,08”
The total length of the line I have calculated graphically with 2 constructed transition radii! And to my surprise there is not really a difference!
for the MA CHR 120 driver:
Revc 7.20 Ohm
F0 34.24 Hz
Sd 147 cm²
Vas 58.8923 Ltr
CMS 1.9409 mm/N
MMD 10.1179 g
MMS 11.1310 g
Xmax 9mm one way
QMS 2.3823
QES 0.4411
QTS 0.3722
LeVc 0.1272 mH
No 0.936 %
SPL0 89.3145 dB
https://www.kjfaudio.com/.../2020/04/CHR-120-twin-pipe.pdf
S d = 147 cm²
S o = 246, 77 qcm = 38,25 square inch
S l = 349,54 qcm = 54,19 square inch
Sl / S 0 ratio = 1,42
Length of the (middle) line = 241, 64cm = 95,13”
Loudspeaker offset ( from S 0) = 11,43cm = 4,5 inch
The total length of the line I have calculated graphically with 2 constructed transition radii! And to my surprise there is not really a difference!
or another example with feastrex D5e Typ III
Akiyama San (Mr. Feastrex) said about the feastrex makoto loudspeaker:
秋山幸仁
“It works like BLH and resonance tube.
It can play up to 25 Hz.”
https://www.dagogo.com/feastrex-makoto-loudspeaker.../2/
MA 12 P gen. 2
Revc 7.00 Ohm
F0 42.149 Hz
Sd 143.410 cm²
Vas 43.060 Ltr
CMS 1.369 m M/N
MMD 9.188 g
MMS 10.217 g
BL 7.540 T.M
QMS 1.981
QES 0.333
QTS 0.285
LeVc 53.952 uH
No 0.936 %
SPL0 91.730 dB
Many thanks in advance for all of your "new" suggestions and tips! But if there isn't any progress, it tends to be the "nandappe" ML - TQWT for the MA 12 P Gen. 2
Kind regards
Stefan
does one of the group members have an idea or a clue. if there is such a cabinet for the Mark Audio Alpair 12 P gen. 2 - are these two cabinets TL designs(?) or are they really backloaded horns? And how have they to be modified for a MA 12 p Gen. 2 driver? So I calculated a bit!?
For MA Alpair 12
Revc = 7 Ohm
F0 = 46 Hz
Qms = 1,45
Qes = 0,42
Qts = 0,33
Vas = 22,00 Liter
Sd = 143 cm²
BL = 8,75 Tm
Le = 0,06 mH
Xmax = 12 mm
http://frugal-phile.com/boxlib/woden/Aln-0v82-map-281209.pdf
S d = 143 cm²
S 0 = 246, 77 qcm = 38,25 square inch
S l = 349,54 qcm = 54,19 square inch
Sl / S 0 ratio = 1,42
Loudspeaker offset ( from S 0) = 19,37cm = 7,625 inch
Length of the (middle) line = 241,51 cm = 95,08”
The total length of the line I have calculated graphically with 2 constructed transition radii! And to my surprise there is not really a difference!
for the MA CHR 120 driver:
Revc 7.20 Ohm
F0 34.24 Hz
Sd 147 cm²
Vas 58.8923 Ltr
CMS 1.9409 mm/N
MMD 10.1179 g
MMS 11.1310 g
Xmax 9mm one way
QMS 2.3823
QES 0.4411
QTS 0.3722
LeVc 0.1272 mH
No 0.936 %
SPL0 89.3145 dB
https://www.kjfaudio.com/.../2020/04/CHR-120-twin-pipe.pdf
S d = 147 cm²
S o = 246, 77 qcm = 38,25 square inch
S l = 349,54 qcm = 54,19 square inch
Sl / S 0 ratio = 1,42
Length of the (middle) line = 241, 64cm = 95,13”
Loudspeaker offset ( from S 0) = 11,43cm = 4,5 inch
The total length of the line I have calculated graphically with 2 constructed transition radii! And to my surprise there is not really a difference!
or another example with feastrex D5e Typ III
Akiyama San (Mr. Feastrex) said about the feastrex makoto loudspeaker:
秋山幸仁
“It works like BLH and resonance tube.
It can play up to 25 Hz.”
https://www.dagogo.com/feastrex-makoto-loudspeaker.../2/
MA 12 P gen. 2
Revc 7.00 Ohm
F0 42.149 Hz
Sd 143.410 cm²
Vas 43.060 Ltr
CMS 1.369 m M/N
MMD 9.188 g
MMS 10.217 g
BL 7.540 T.M
QMS 1.981
QES 0.333
QTS 0.285
LeVc 53.952 uH
No 0.936 %
SPL0 91.730 dB
Many thanks in advance for all of your "new" suggestions and tips! But if there isn't any progress, it tends to be the "nandappe" ML - TQWT for the MA 12 P Gen. 2
Kind regards
Stefan
Hi LeifB60,
thx - well, that is the cabinet for the Alpair 12. The only difference between this two "twin - pipe" cabinets is the speaker offset in relation to S0. Modyfying for the MA 12 P Gen. 2 it should be usefull to set the two speaker offsets and V as in a ratio. Vas 58,89 / Vas 40,060 = 1,368 x 4,5" = 6,156" = 15,63 cm speaker offset for a MA 12 P Gen. 2.
regards
Stefan
I have asked Scott for an updated Ain… perhaps you can poke him too.
dave
dave
FYI/FWIW, the driver is irrelevant other than whether or not it will physically fit at the desired offset with the offset in round numbers is the acoustic pipe length x 0.21, i.e. acoustic 5th harmonic; all drivers, vents should be at an odd harmonic. This one was ~0.21315, i.e. within rounding numbers in fractions of an inch, so could just as easily be rounded to nearest cm or mm.
Also,as MJK proved, the offset shifts a bit downward with increasing harmonic due to the end being open (lossy), though in most cases it doesn't audibly affect just using 1st, 3rd, 5th, etc., due to the usual added damping/stuffing.