Trying to decide on MarkAudio or SB Acoustics for MTM retrofit

[Rennie]

Just to clarify, the first image is 2 woofers connected in parallel and still installed in the cabinet? Or you have taken the measurement with XO and tweeter connected (guessing this is with XO 🙂)?

The measurement indicates that the Fb is ~40 Hz.

One idea is add a little more Dacron type poly-fill inside the cabinet and see if you can get rid of the third hump. The poly-fill should be well fluffed.

Stock L is with everything installed into the cabinet; impedance of the speaker

 

[zman01]

Now coming back to the question about installing new drivers in the existing cabinet to improve the sound.

One of the options that the OP had in mind was the Pluvia 11. The Mark Audio CHN-110 is a driver with similar physical dimensions.

Pluvia 11 specs:
FS: 39.118
VAS: 24.751 ltr
RE: 5.4 Ohms
QMS: 1.797
QES: 0.351
QTS: 0.293
dBSPL: 88.131 dB
X Max 7mm 1 way
Pwr: 45watts Nom

CHN-110 specs:
FS: 44.1601 Hz
VAS: 24.7335 L
RE: 6.8000 Ω
QMS: 2.86
QES:0.4884
QTS: 0.4172
dBSPL: 88.4186
L1kHz : 0.2771 mH
L10kHz: 0.1229 mH
X Max 8mm 1 way
Pwr: 45watts Nom

MLTL design from MA website for a single CHN-110:

https://www.markaudio.com/wp-content/uploads/2022/09/Kewel-CHN110-compact-MLTL.png

 

[zman01]

Any progress Rennie on the retrofit?

40 liters is slightly smaller than the 48 liter cabinet in the link above, but CHR-120 might still work; and a Pluvia 11 might be good for ~40 liters.

 

[wolf_teeth]

If the 3rd peak does not disappear with better/more damping, it could be a double chamber design and actually have 2 tunings.

 

[Rennie]

Any progress Rennie on the retrofit?

40 liters is slightly smaller than the 48 liter cabinet in the link above, but CHR-120 might still work; and a Pluvia 11 might be good for ~40 liters.

Nothing new yet, I have two driver holes so I'm wondering how these drivers would go if they have to share the 40L.

 

[Rennie]

If the 3rd peak does not disappear with better/more damping, it could be a double chamber design and actually have 2 tunings.

I can try and look more carefully at the bracing to see if it's anything other than holey cheese, though the little peak was still there with a hand over the port