for all the speaker guys, my 18 farts

You're probably clipping the power amp if it "farts."

Answer? Stop doing it before you blow your speaker.

 

Bad chords going from your head to cab?
Your 18 might be blown?
Make sure your 18 IS a bass speaker.

 

That's a decent woofer. Since you say the amp isn't clipping, it sounds like you are driving the system with too much low bass and the woofer is bottoming out. My guess is the tuning of the box is too high and you are pounding out too much signal below its tuning frequency (e.g., maybe a low B at 31 Hz.). This is an example of doing mechanical damage to a speaker that is rated for much higher power handling than the amp can deliver. You may have already done some mechanical (not thermal) damage to it, but the first thing to do is make sure the box tuning is right for the driver. There are many earlier threads and good resources on this subject in this forum. Do a search for "cabinet building 101" and that kind of thing.

And if you aren't driving your amp into clipping, even when slapping, a bigger power amp isn't going to help this situation particularly.
- Mike

 

And if it start's smelling......you burnt it up.

 

The Omega Pro 18" is optimum in 3.12 cubic feet tuned to 42 Hz. It can be run in a 1.63 cubic foot sealed enclosure but the bass will roll off from middle E (80 Hz) and down. But... the driver cone will be fully loaded and receive the maximum protection the cabinet can offer. However, the bass response will really suck.

If you are playing a 4 string bass, the ported tuning above is ideal for you. It will offer the maximum port loading at low E which means you will have almost no cone movement.

I suspect your homebuilt cab is not tuned correctly. Hook the cab to an amplifier driven by a computer sound card. Put a 100 ohm resistor in series with the cabinet. Use a digital volt meter and measure across the cabinet connectors. Get a free sound generator from my site in my signature below. Sweep the signal down and read the DVOM in A/C mode. The point of lowest voltage is the tuning frequency of your cabinet. It will coincide with the least amount of cone movement. If not, your cab has air leaks.

If your cab is tuned too high, it will unload the speaker at notes lower than the tuning which is very unhealthy for the speaker and you will trash it. The more it farts, the more damage is done to it.

 

This is an oversized extended bass shelf tuning. An EBS alignment is 125% to 175% larger than optimum, but yours is larger than this. This alignment extends low bass response at the expense of reduced power handling and degraded transient response below the tuning frequency. This alignment should never operate below the tuning frequency due to the very high cone unloading.

Since you are a 5 string player, my suggestion is to accurately tune this box to 31 Hz using a digital VOM. This will provide maximum cone loading and protection at low B, where you need it the most. The cone will hardly move at all at low B (no farting) and all the sound will come from the port. You will have to make the port duct longer to lower the tuning.

To solve you farting problem experiment with running both the Omega Pro and the 2x10 in full range mode. If I remember right, the RC210 bi-amp crossover point is at 200 Hz, which is G string, 12th fret. This means the 18" is generating the entire fundamental and the 2x10 are loafing and not carrying any of the load except harmonics.

 

With the amp you're using, I wouldn't worry about overpowering the 18" - so no need to cut the highs. I would do just the opposite: cut the lows to the two 10s, if anything, to protect them from overexcursion. Yes, the lowest bi-amp frequency on the Carvin head is (unfortunately) 200 Hz. Poor choice on Carvin's part. I run my rig full-range into both channels (one feeding my Carvin 2x10 and the other feeding either an Eden 2x15 or Carvin 1x18), except I insert a simple high-pass filter (capacitor) into the preamp/amp loop on my 2x10 channel to attenuate the lows.
- Mike