Interest Check - Custom Fane 15" Full-Range

Which version of the 15" full-range unit would you prefer?

  • A - Upgrade the magnet only

    Votes: 15 37.5%
  • B - Upgrade the magnet, swap to cast aluminium basket

    Votes: 9 22.5%
  • C - Bigger magnet, aluminium basket, bigger voice coil

    Votes: 13 32.5%
  • D - None - the original is fine.

    Votes: 3 7.5%

  • Total voters
    40
I think the driver is fine the way it is, for my purposes at least. Materials are basic but adequate. I have them in 350-400 liter enclosures in my living room and this does not bother me. Response digs below 20Hz in-room. Dynamics are good. I probably wouldn't have started my project with these had they been more expensive.

Also, GM and I see an intriguing correlation between performance of the Fane and the RCA LC1A driver. Its response in certain classic designs overlays with that of the RCA as measured the in same designs. It's like that is intentional. Trying to improve on the LC1A is not going to be trivial. ;-)

On a more serious note, I think there is solid and thoughtful engineering behind the Fane 15. The parts work together as is. If a bigger magnet would make it voxative/feastrex league, I'm sure Fane would glue on a few pennies worth of extra magnet and sell it for feastrex/voxativ prices.
 
isn't Hoffman's iron law here somewhere - you want high sensitivity in a small box and deep bass ... hmmmm

While true, this driver is somewhere below the curve.

The best-in-class drivers are right at the edge of what Hoffman will allow - PA subs manage reasonably high sensitivity with useful LF extension. PA midbass drivers sacrifice some extension, but gain sensitivity. HT subs go very low, but aren't particularly sensitive.

This driver won't match the best-in-class in any of those cases. I'd like a custom build that would at least get close.

Chris
 
Hey Chris, what was the diameter of the vent hole on the back?

Maybe it can work better to fill the hole with neo slugs?

Possibly.

I'm beginning to think that it could be the small voice coil diameter. A 2" coil on a 15" driver is quite small! Perhaps they focused all the magnetic flux they could at it. ie, adding more magnet, or moving to neo, wouldn't help.

Chris
 
Addinh extra magnet - or shorter voice coil for valve amps

Adding an extra magnet of possibly the same size by glueing it on the existing one with the magnets working against each other brings usually +1db efficency. This can be done with the standard driver available today.

102 db of efficiency would be indeed outstanding with a bigger magnet.

Alternatively a second version of the 15-300TC could also have a shorter travel of +- 2.5 mm or even +.-1.5mm instead of +-3.5 mm. This would also bring efficiency up due to more wire in in the gap and a lighter voice coil - and some more high frequency response for free.

This makes especially sense with low power amps like valves with only some watts. They can not use the +-3.5 mm cone travel however.
So a shorter travel would only be a gain.


For me the driver is also very good as is. Due to the fact that a higher Q means a higher effiency in the bass region. I discuss this here:

Just wanted to show off my new 18in build

This 18 inch build is a subwoofer project I realized with 18 inch drivers: for this I chose cheap drivers with light magnets and a steel basket because I wanted to keep the enclosure lightweight without buying expensive neodym-type bass loudspeakers. I want to transport these speakers alone without a second person for helping me to carry them.

So high - Q cheap drivers with little magnets can be a first choice. As i always use DSP power to make the amplitude linear and extend the response down to 30 or 20 Hertz.



Yours, Dragan from germany
 

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Hi all,

I'm running an interest check first of all.

The Fane 15" full-range driver ...

I can see a few options here:

A - Same moving parts, just add more magnet
B - More magnet, cast aluminium frame
C - More magnet, cast frame, bigger voice coil aiming for more cone excursion and power handling.
D - Don't bother, the original is fine
I voted for A.
I am strongly against C, because it will skyrocket the price of the whole driver (and the reconing kit, also). Although, the higher height of the voice coil (the same diameter!) will bring welcomed increasing of Xmax, at penalty of lower SPL - which is fine with me, in a view of an already high sensitivity.

Instead of 15" version, I would suggest bigger magnet for the 12" version which is more home friendly.