You can use stronger aluminium foil and you can hear the difference. There is foil for isolating sauna. Its 3x stronger than household foil. But its also 3x more heavy.
For a PA speaker driven by battery I took the household foil with very good sonic results. Its enough. You can use much thinner material and still the sonic benefit has a dominant influence on the transients in music.
Duraluminium can not be applied to Nawi-Cones. D A Barlow used for the Leak Sandwich loudspeakers made with polystyrol cones duraluminium sheets of foil. But the cone is a straight cone.
Nawi loudspeaker cone with less hard aluminium foil minimizes resonances. I have no experience with using duraluminium.
I thought once to buy Titan foil but never bought it in order to try it out.
I have a pair of Leak Sandwich loudspeakers. For me these are true high end loudspeakers in the 60ies until now.
For a PA speaker driven by battery I took the household foil with very good sonic results. Its enough. You can use much thinner material and still the sonic benefit has a dominant influence on the transients in music.
Duraluminium can not be applied to Nawi-Cones. D A Barlow used for the Leak Sandwich loudspeakers made with polystyrol cones duraluminium sheets of foil. But the cone is a straight cone.
Nawi loudspeaker cone with less hard aluminium foil minimizes resonances. I have no experience with using duraluminium.
I thought once to buy Titan foil but never bought it in order to try it out.
I have a pair of Leak Sandwich loudspeakers. For me these are true high end loudspeakers in the 60ies until now.
Attachments
I did not measure before and after putting the extra magnet. But you can clearly hear the difference.
I had to put the 4 ohms in line with the tweeter out of the way to adapt the loudness of the tweeter to the tweaked bass driver. Which is working without any filter directly driven like a fullrange driver in the Thomann bluetooth box.
And I had to change the damping in the box.
As the driver has a not very strong magnet I have put enough damping into it to make it sound good in the bass.
With the extra magnet I have put some damping out because it sounded overdamped.
So all this shows that the driver at least got 1 db more in efficiency maybe more. But usually you get 1-2 db more and at least a reduction of Qts of 0.1
I had to put the 4 ohms in line with the tweeter out of the way to adapt the loudness of the tweeter to the tweaked bass driver. Which is working without any filter directly driven like a fullrange driver in the Thomann bluetooth box.
And I had to change the damping in the box.
As the driver has a not very strong magnet I have put enough damping into it to make it sound good in the bass.
With the extra magnet I have put some damping out because it sounded overdamped.
So all this shows that the driver at least got 1 db more in efficiency maybe more. But usually you get 1-2 db more and at least a reduction of Qts of 0.1
As it is nice to have good lightweight enclosures like the BP115a you can also put this beast into the box and leave the tweeter out.
Maybe you can sell the original bass drivers. They are very low cost.
I liked the idea to keep the bass and to tweak it as I know how to do it with little money and good sonic results.
Fane Sovereign 15 300 tc
This driver sounds good from scratch. Without aluminium foil it sounds good I did not expect that. They made the paper pretty stiff I never saw such a well constructed fullrange driver. You can get it only used as it is out of production.
Maybe you can sell the original bass drivers. They are very low cost.
I liked the idea to keep the bass and to tweak it as I know how to do it with little money and good sonic results.
Fane Sovereign 15 300 tc
This driver sounds good from scratch. Without aluminium foil it sounds good I did not expect that. They made the paper pretty stiff I never saw such a well constructed fullrange driver. You can get it only used as it is out of production.
Attachments
Do not know. Tweeter has a capacitor of 2.25 mfd in line. Do not know what inductivity the coil has.
See
https://www.diyaudio.com/community/threads/tuning-tweaking-of-bp-115-a.375464/post-6745386
See
https://www.diyaudio.com/community/threads/tuning-tweaking-of-bp-115-a.375464/post-6745386
Before the tweak of the tweeter with foil sandwich the difference in sound with the 4 ohm in series to the tweeter turned off and on with the implemented switch was:
just a bit louder without this resistance.
Now you can clearly hear the difference in distortion with or without that resistance.
In theory this resistance converts the tweeter to current drive minimizing distortion from the voice oil moving in the magnet system.
However this is masked by the resonances of the dome. Distortion induced by material resonances of the mylar and or damping of the center pole.
Quite well audible now sound/distortion difference while switching this resistor on and off .
just a bit louder without this resistance.
Now you can clearly hear the difference in distortion with or without that resistance.
In theory this resistance converts the tweeter to current drive minimizing distortion from the voice oil moving in the magnet system.
However this is masked by the resonances of the dome. Distortion induced by material resonances of the mylar and or damping of the center pole.
Quite well audible now sound/distortion difference while switching this resistor on and off .
Whoever wants to learn how to put aluminum foil on cones here I describe it:
https://www.diyaudio.com/community/threads/how-to-make-a-loudspeaker-sandwich-cone.402917/
Example: Fane Sovereign 15-300tc with sandwich alu foil tweak
https://www.diyaudio.com/community/threads/how-to-make-a-loudspeaker-sandwich-cone.402917/
Example: Fane Sovereign 15-300tc with sandwich alu foil tweak