Speaker has a bit too much energy at 500Hz, how to reduce this

[Tino]

Hi guys, I've built a speaker that *should* be quite flat but I find it a bit thick in the midrange area sometimes and using my old audiocontrol RTA, I see a about 3db too much energy at around 500Hz. I believe this is not from the drivers or crossover but cabinet resonance or damping problem.

What material could I use in the speaker to line the walls that might reduce output in this range? Right now I've used about 1" thick fiberglass insulation (I know its not great) for the side, top, bottom and rear of the cabinet walls. The front panel where the drivers are mounted do not have any insulation though.

Any suggestions?


PS. Other than this problem, the rest sounds really good IMO. Its a Vifa 2 way setup.

[tinitus]

Originally posted by Tino


I believe this is not from the drivers or crossover but cabinet resonance or damping problem.

Actually its most likely driver/xo related

Too much BSC maybe ?

xo design/schematic ?

Is it ported ? a port might do such things too

[auplater]

I'm with tinnitus on this... I'd expect subtle changes in the xover might tame the rise... perhaps a shelving network could help on the woofer...

John L.

[Tino]

Hi guys, here is the thread about the crossover. Any suggestions welcome

Crossover for vifa 2 way setup - how can I find out what this crossover is doing?

Also maybe its my room which is a 10' x 12' but my old usher S520 didnt have this slight rise in that area but the overall curve on the ushers looked a lot more jagged than what I just built. I just want to see if I can remove the slight extra warmth...its subtle but it would make me happy

[auplater]

You could try this simple notch filter to see if anything improves

http://www.carstereo.com/help2/Articles.cfm?id=19

John L.

[tinitus]

Have you tried to reverse tweeter polarity ?

Also, maybe try a little less attenuation on tweeter

And maybe try to remove the 0.47uf/6.8ohm notch parts across the series coil, and instead mount RC in paralel after coil
I dont say its better, but may be worth a try
May need lots of adjustments until properly working
With RC mounted, I would try how it sounds with CLR notch disconnected(just lift one component)

Are you using original suggested by shop, or the modified by Inductor?

[Tino]

Hi tinitus, I'm using the original shop crossover design. Also I did add a bit more sound dampening inside the cabinet and I believe I have make it slightly better. I mean the sounds is still very good IMO but it is a little on the warmer side but not in a bad way.

I'll also try what you suggested and see how it goes. I'm going to buy more xover parts and make a second set of crossovers just to play with

[augerpro]

How are they positioned? The wall often has a large influence here. Move them away or towards teh wall and see if that helps or hurts.