this post can fall into many categories so Im starting here . I Decided to build my own cabinet . Dimensions are 17W x16 1/2 high by 13 Deep . the cabinet will be used for a bass guitar, I purchased a Eminence Kappa-Lite 3012LF-4 .According to the specs at eminence the speaker is rated at 550Watts ,1050 Peak The Amp is a Genz -Benz Shuttle 6.0 out put is 600 Watts@ 4 Ohms . At extremely low volume (2 and lower)it sounds ok but as soon as you turn it up lets says a little less than half way the speaker makes a terrible flapping noise. the noise is more prominent on the E and A string I have never heard a speaker do this . Does it sound like it being over powered ??? or do I just have a bum Speaker ??
With respect to the cabinet size I know the cabinet is slightly under sized for this speaker as also the amount of ports on the cabinet .
The second question is , is it possible at all that because the cabinet is not the recommended size that the speaker would blow . I mean where not talking about putting an elephant in a shoe box here
I since have returned the speaker and awaiting replcement , but I am weary about blowing the second speaker .
With respect to the cabinet size I know the cabinet is slightly under sized for this speaker as also the amount of ports on the cabinet .
The second question is , is it possible at all that because the cabinet is not the recommended size that the speaker would blow . I mean where not talking about putting an elephant in a shoe box here
I since have returned the speaker and awaiting replcement , but I am weary about blowing the second speaker .
Is the cabinet ported? The combination of a too-small cabinet and a too-short port unloads the driver below the (higher than expected) resonant frequency. This can certainly cause the driver to bottom as you describe, and can potentially destroy it.
If ported, try stuffing the port.
If ported, try stuffing the port.
Sealed cabinets are best for stopping speakers hitting the end stops.
The air in the cabinet gets compressed and pushes back on the speaker.
Ported cabinets need a high pass filter to stop the frequency getting low enough to get excessive excursion of the cone.
The air in the cabinet gets compressed and pushes back on the speaker.
Ported cabinets need a high pass filter to stop the frequency getting low enough to get excessive excursion of the cone.
So I guess I need to add some data , there is a cross over and a horn in the cabinet as well . When I get the new speaker I will try stuff up the port hole . I thought the port hole was designed such that the air can breath as the speaker flexes.
kinda sorta the port is meant to breathe at one particular frequency.
as a musician you should have an appreciation of "tuning" and in the case of bass reflex it's about tuning to the drivers resonant frequency if it's off, like an out of tune string it's not going to sound right.
a bass reflex/Helmholtz resonator is supposed to be an "air brake" for cone excursion at resonance.
as a musician you should have an appreciation of "tuning" and in the case of bass reflex it's about tuning to the drivers resonant frequency if it's off, like an out of tune string it's not going to sound right.
a bass reflex/Helmholtz resonator is supposed to be an "air brake" for cone excursion at resonance.
the box is made of 3/4 inch birch covered ply . the horn is
https://www.eminence.com/speakers/supertweeter-detail/?model=BGH25_8
https://www.eminence.com/speakers/supertweeter-detail/?model=BGH25_8
...and no brake at all for the cone at frequencies below that port resonance, as others have been saying.
Five-string basses in standard tuning go down to 30 Hz, four-strings to 41 Hz. It would probably be wise to make sure the port tuning is below 30 Hz, if a 5-string bass might someday be used with this cab.
The other thing to remember is that a ported enclosure often suffers from low-frequency ripples in the frequency response and/or associated boominess at some frequencies. Not ideal qualities for a bass guitar amp to have.
-Gnobuddy
Ok, thanks for all the replies . I downloaded a speaker cabinet tool and according to the specs I put in . the cabinet is defiantly too small for that speaker . So I was thinking . If I put the same speaker in , but made it a 8 ohm speaker so now the amp would only push 350 watts max. would that make any difference or Am i barking up the wrong tree entirly ???. Or do I just need to find the right speaker for that cabinet ?? do you know if there is a soft ware tool that works the opposite . Where you input the cubic feet of the cabinet and it gives you speaker values ??
The cabinet is within the range of volumes recommended on the Eminence spec sheet, for whatever that's worth. (I don't think they specified sealed or ported, however, and a sealed box can be smaller than a ported one.)
I guess the two most relevant questions are:
- Are you happy with the sound from your current cab/speaker at low volume (when there are no flapping noises)? No "boom"? No "woofy" notes? No obvious louder or softer notes? Transients are to your taste?
- How loud do you want your bass to be?
Your answer to the second question is key. If you don't feel the need for half a kilowatt of audio power, you can always simply turn down the volume knob...🙂
I still think stuffing a few old socks in the port is the first thing to try, when the new speaker gets to you. And don't turn your amp up to full power, turn it up until it's loud enough to get the job done - no louder!
Are there any commercial 500-watt bass rigs out there that use just one single 12" driver? 😕 If not, that may be simply too much sheer bass power to ask one driver to cope with.
-Gnobuddy
Maybe the driver was never designed for a ported application ?
Fane speaker specs say whether the speaker is suitable for ported or just sealed cabinets.
What does the spec say on your speaker ?
Fane speaker specs say whether the speaker is suitable for ported or just sealed cabinets.
What does the spec say on your speaker ?
The speaker is defiantly designed for ported
https://www.eminence.com/speakers/speaker-detail/?model=Kappalite_3012LF_4
https://www.eminence.com/speakers/speaker-detail/?model=Kappalite_3012LF_4
You said you've got a speaker by Eminence? Well, there's a tool from that factory, primarily dedicated to their own products (but may as well used for others, as far as you know the TSP's): the Eminence Designer. Google for it!
- Status
- Not open for further replies.