Hello,

This question has been asked before, but the answer was somewhat vague since they mention that the parameters R(e), L(e), Sd, V(as) and BL will be twice as much and the sensitivity +3db as for a driver when two of them will be connected in series. They also mention that Qes, Qms, and Qts do not change, remaining the same as for a driver.

To the above, if supposedly they are two different measurements, they only mention that it will be the one of a single driver without establishing which one (??)

Performing measurements on two woofers of the same model and brand with the Dayton Audio DATS V3 parts-express measuring equipment, the following results are obtained:

Woofer 1:

Piston Diameter = 123.2 mm

f(s)= 37.15 Hz

R(e)= 3,784 Ohms

Z(max)= 53.11 Ohms

Q(ms)= 5,136

Q(es)= 0.3941

Q(ts)= 0.366

V(as)= 19.86 liters (0.7015 cubic feet)

L(e)= 0.6089 mH

n(0)= 0.2463 %

SPL= 86.02 1W/1m

M(ms)= 18.44 grams

C(ms)= 0.996 mm/N

BL= 6.429

K(r)= 0.02554

X(r)= 0.5509

K(i)= 0.006714

X(i)= 0.7044

Woofer 2:

Piston Diameter = 123.2 mm

f(s)= 35.36 Hz

R(e)= 3,795 Ohms

Z(max)= 53.98 Ohms

Q(ms)= 5.07

Q(es)= 0.3834

Q(ts)= 0.3564

V(as)= 22.25 liters (0.7856 cubic feet)

L(e)= 0.5943 mH

n(0)= 0.2446 %

SPL= 85.98 1W/1m

M(ms)= 18.17 grams

C(ms)= 1,115 mm/N

BL= 6.321

K(r)= 0.02539

X(r)= 0.5508

K(i)= 0.006462

X(i)= 0.7087

If I make a measurement of these connected in series, specifying that the equivalent diameter by the sum of the surface of both (119 cm2 X 2) is 174 mm, the following results are obtained:

Woofers 1 and 2 connected in series and tested with Dayton Audio DATS V3:

Piston Diameter = 174 mm

f(s)= 35.56 Hz

R(e)= 7,654 Ohms

Z(max)= 105.1 Ohms

Q(ms)= 4,807

Q(es)= 0.3776

Q(ts)= 0.3501

V(as)= 37.9 liters (1,338 cubic feet)

L(e)= 1,191 mH

n(0)= 0.4305 %

SPL= 88.44 1W/1m

M(ms)= 41.96 grams

C(ms)= 0.477 mm/N

BL= 13.79

K(r)= 0.053

X(r)= 0.5467

K(i)= 0.01338

X(i)= 0.7049

According to these results, all the parameters varied. Qes, Qms, Qts and F(s) are all close to the values of a single woofer. R(e) changed approximately twice, the same for Z(max), V(as), L(e), n(0), M(ms), BL, K(r) and K(i) . C(ms) is about halfway through.

From all this, four questions:

1. Is it correct to make a measurement of the T/S parameters with speakers connected in series to obtain these and take them as a basis for the calculation of the box as if you were using a single driver as the combination?

2. Is there any mathematical model to reach a conclusion of the T/S parameters to calculate a box?

3. Why does the variation of information between the data obtained by Dayton Audio DATS V3 and the original technical specifications of the manufacturer where it is mentioned that the F(s) = 43 Hz?

4. Regarding item 3, what is the correct data to use for the calculation of a box, Morel Data Sheet, or Dayton Audio DATS V3 results?

Thank you.

(Sorry for the "parallel" mistake, I had to re-edit the post, so instead I put "series")

Translated with www.DeepL.com/Translator (free version)

This question has been asked before, but the answer was somewhat vague since they mention that the parameters R(e), L(e), Sd, V(as) and BL will be twice as much and the sensitivity +3db as for a driver when two of them will be connected in series. They also mention that Qes, Qms, and Qts do not change, remaining the same as for a driver.

To the above, if supposedly they are two different measurements, they only mention that it will be the one of a single driver without establishing which one (??)

Performing measurements on two woofers of the same model and brand with the Dayton Audio DATS V3 parts-express measuring equipment, the following results are obtained:

Woofer 1:

Piston Diameter = 123.2 mm

f(s)= 37.15 Hz

R(e)= 3,784 Ohms

Z(max)= 53.11 Ohms

Q(ms)= 5,136

Q(es)= 0.3941

Q(ts)= 0.366

V(as)= 19.86 liters (0.7015 cubic feet)

L(e)= 0.6089 mH

n(0)= 0.2463 %

SPL= 86.02 1W/1m

M(ms)= 18.44 grams

C(ms)= 0.996 mm/N

BL= 6.429

K(r)= 0.02554

X(r)= 0.5509

K(i)= 0.006714

X(i)= 0.7044

Woofer 2:

Piston Diameter = 123.2 mm

f(s)= 35.36 Hz

R(e)= 3,795 Ohms

Z(max)= 53.98 Ohms

Q(ms)= 5.07

Q(es)= 0.3834

Q(ts)= 0.3564

V(as)= 22.25 liters (0.7856 cubic feet)

L(e)= 0.5943 mH

n(0)= 0.2446 %

SPL= 85.98 1W/1m

M(ms)= 18.17 grams

C(ms)= 1,115 mm/N

BL= 6.321

K(r)= 0.02539

X(r)= 0.5508

K(i)= 0.006462

X(i)= 0.7087

If I make a measurement of these connected in series, specifying that the equivalent diameter by the sum of the surface of both (119 cm2 X 2) is 174 mm, the following results are obtained:

Woofers 1 and 2 connected in series and tested with Dayton Audio DATS V3:

Piston Diameter = 174 mm

f(s)= 35.56 Hz

R(e)= 7,654 Ohms

Z(max)= 105.1 Ohms

Q(ms)= 4,807

Q(es)= 0.3776

Q(ts)= 0.3501

V(as)= 37.9 liters (1,338 cubic feet)

L(e)= 1,191 mH

n(0)= 0.4305 %

SPL= 88.44 1W/1m

M(ms)= 41.96 grams

C(ms)= 0.477 mm/N

BL= 13.79

K(r)= 0.053

X(r)= 0.5467

K(i)= 0.01338

X(i)= 0.7049

According to these results, all the parameters varied. Qes, Qms, Qts and F(s) are all close to the values of a single woofer. R(e) changed approximately twice, the same for Z(max), V(as), L(e), n(0), M(ms), BL, K(r) and K(i) . C(ms) is about halfway through.

From all this, four questions:

1. Is it correct to make a measurement of the T/S parameters with speakers connected in series to obtain these and take them as a basis for the calculation of the box as if you were using a single driver as the combination?

2. Is there any mathematical model to reach a conclusion of the T/S parameters to calculate a box?

3. Why does the variation of information between the data obtained by Dayton Audio DATS V3 and the original technical specifications of the manufacturer where it is mentioned that the F(s) = 43 Hz?

4. Regarding item 3, what is the correct data to use for the calculation of a box, Morel Data Sheet, or Dayton Audio DATS V3 results?

Thank you.

(Sorry for the "parallel" mistake, I had to re-edit the post, so instead I put "series")

Translated with www.DeepL.com/Translator (free version)

## Comment