GK MB 115 cab w/ Eminence DeltaLFA HELP

9M2E · #1 12-21-2012, 01:13 PM

Hi Everyone,

I had the speaker go in my MB115 cab and replaced it with an Eminence Delta15LFA. I put a set of the delta LFA 12's in my mb212 combo and it made it a flipping monster, it has so much bass you have to roll it back when you're playing indoors. it has a ton of low end. I use a 700rb head and mb410/mb115stacked for gigs. I was expecting a similar result with this replacement but find that low end seems to be farting out/ is lacking low end as the factory speaker did. Could this be an issue with the size of the cab? Should I put another port hole in it so more air can escape? or is my issue that the MB heads produce more bass/sub bass vs the RB heads? I know this delta lfa's can produce earth moving bass... i can't wait to hear what everyone has to say... happy holidays!

Technotitclan · #2 12-21-2012, 01:38 PM

Could be the tuning of the cab doesn't match what is needed for the speaker. Every speaker needs a different design cab to get the most out of it. Looks like you got lucky with the 12's but the 15 just doesn't match. I'm sure some of the better educated members here will be able to provide you with the maths involved. A different model speaker might be in order. You can always take measurements of the inside of the cab and email eminence asking for recommendations.

Technotitclan · #3 12-21-2012, 01:38 PM

Also double check wiring. Do the 9V battery test.

9M2E · #4 12-21-2012, 01:50 PM

Quote:

Originally Posted by Technotitclan

Also double check wiring. Do the 9V battery test.

.

It's hooked up right but what is this test you speak of?

Technotitclan · #5 12-21-2012, 02:00 PM

plug a speaker cable into the cab then touch the tip of the other end to the pos(+) of a good 9V and the other part of the plug to the neg (-) terminal of the battery. What should happen is it will push the cone out I believe. If the cone goes in then your + and - are mixed up in the cab.

will33 · #6 12-21-2012, 02:05 PM

Touch the battery terminals to the tip and sleeve of your speaker cable plug (while it's not plugged in the amp). The speakers will jump. Make sure they all jump out together and jump in together when you reverse the battery. Reverse the wires if one is moving the wrong way. Might have to rig a couple wires to do it if you have speakons.

Yes, you got lucky with the 212. Use WinISD, or put some salt or rice on the speaker cone while it's laying on it's back and run sinewaves through until you find the one that makes the rice jump the least. That is the frequency the cab is tuned to. Some port modification might be needed to get the most out of the speaker. They tuned the box to the speaker....they're not to let air "escape".

There are many websites you can use to play the test tones...also smartphone apps that do it. Rig up a wire to plug in your computer or phone on one end and the cab on the other.

Line and brace the cabs if they are not. There's a thread on that around here somewhere.