OBC115 - Farting at moderate volume?

[majortoby]

Yeah, it sounds to me like the box is just getting more than it can take. Unfortunately, this is coming among mass-produced cabinets. It's only very recently, and in the custom/DIY sector that we see the emergence of speakers that can ACTUALLY take some REAL abuse! These are the days to be a bass player!

 

[rodl2005]

Bass eq on 10 will fart out near any 15 one loud.
Turn down ur bass on ur amp. That box is basically an EV TL606 so a 3015 non lf will suit fine.
I'd first turn down the bass eq, line the cab with poly quilt padding.

 

[majortoby]

My recommendation:
1. Toss in a Faital Pro 15PR400. Great speaker, great tone, well-suited to that box, can put out mucho bass, and move a ton of air.
2. Put in some material as a cabinet lining/fill. It'll greatly improve the cabinet's dynamics.

That would be what I do in this case. You may not be pleased with the cab as it is right now, but you've got a nice orange box to put a serious speaker in!

 

[wounded horse]

It never ceases to amaze me that so few bass players - and FOH sound guys for that matter - understand EQ. It's a series of little amplifier segments, divvied up by sections.

Take the cover off the cab. Set bass knob at zero. Set master at something modest, like 2. Play low E. Watch cone excursion. Now set bass at your preferred level of 10. leave master alone. Play low E. Watch cone excursion. It's massively bigger. Hence a lot more volts, hence you've probably got black spot on the voice coil. You could see this if it was a black widow driver by removing the 3 bolts and popping the magnet. I've done it twice, toasted 2 black widow 15s. Did I learn my lesson the first time? No I didn't.
But you don't have black widows. I nearly gurantee, though, that you've overheated the driver. The bottom end will drop dramatically accompanied by a rasping noise.

you don't need 10/10 on the bass control. It'll be be a lot of mud in an attempt to hang with a loud band. If, OTOH, you do need 10/10, as in you're in a reggae band, as Bill says, you need more cabs. A lot more. The driver in the cab you've bought will be a pile of doo doos.

 

[BogeyBass]

This touches on every thing well covered here and things learned the hard way.

Cranking the bass sounds ok when solo at low volumes, especially to a young ear, and actually rather fun no matter how old to push the lows. heck after all it is "Bass"

problem is at high volumes extra bass boost will just distort speakers and get lost in the mix. Likewise mismatched speakers 1x15 and 4x10 will just cancel out and cause over EQ and lower SPL cabinet (the 15) will get damaged trying to keep up with a 4x10

Keep in mind a single 1x15 is about the same as a 2x10 roughly 97 to 99dB, and if you trying to get massive bass out of a 2x10 or a 1x15 at high volumes, it aint gonna work.

4x10 is roughly double the volume, and trying to force a 2x10 to keep up with it, is impossible. A 2x10 or 1x15 will be damaged or go into high distortion over excursion. Trying to keep up with a cabinet that is twice as loud.

Basically a equal 15" cabinet to the 4x10 would be a 2x15, to get equal volume and distortion free sound.

Likewise even if equal a mismatched setup of 2x15 and 4x10 would be a canceling phased out mess.

Either use the single 4x10 to get the volume you need, and if you need more low end

Then just use the standard 2x15

likewise if a 100 to 102dB 4x10 or 2x15 is still not enough distortion free volume....then simple double up to the standard
8x10 or simply use 2, 2x15's

Run your orange EQ's all straight up a 12 o clock, and then boost the mids for more presence in the mix...not the bass.
Cut the treble down to your liking.

And most likely your 15 has a damaged voice coil from being pushed so hard, or as said with the bass dimed...its no different than a 2x10. Anybody having used a 2x10 at high volumes knows already its gonna be fart city.