Coil with resistor in parallel for midwoofer?

[martinbls]

Hi all!

I have a 8" carbon fibre midwoofer that behaves fairly well when it comes to cone breakup problems. Originally this driver is intended to run without any crossover at all. While this works pretty well, I often find the midband to be a tad too loud relatively to the lower frequencies. To adjust the tweeter level I can put a small resistor in series, but to lower only the midband range of the midwoofer I had the idea of using a coil (say, 1,2mH), paralleled with a resistor (say, 2,2R) in series with the midwoofer. This way I would have a driver "without" crossover but with a slightly recessed sound pressure level in the mid frequency range.

Any thoughts about this idea?
Does the amp run into trouble with this?
Are there any odd phase shift phenomenons?

Reason why I ask this is because I find this idea quite good, but I never ever saw this realized in any crossover of any loudspeaker before!

Thanks a lot!
Martin

[LineArray]

What you do is a shelving filter. Nothing to say against
it, if indicated and commonly used in many loudspeakers
too ....

You additionally may try compensating the driver's voice
coil inductivity and see, whether you can use a different
alignment of the L R circuit, maybe the inductor can be
made considerably smaller.

That does not mean, compensating the VC inductivity
is necessarily "better" with your special combination.
It is an option.

Cheers

[martinbls]

Hi Oliver,

thanks for your reply!
I tried a zobel network for impedance linearisation and really, the coil can be much smaller that way (in my case about half the value). But even though there are benefits when using a smaller coil, there are some drawbacks. I used proper values for the zobel (both calculated and measured), but the sound of the driver got more liveless and uninvolving! A larger coil and no zobel always resulted in a more open and exciting sound.

Thanks again!
Martin