Too Much port Area, how do I know?

[spectorfreak]

Aguilar made a GS112 with an airhead?

Guess he maybe has one of these? SOLD - Reduced/ Aguilar AG 500 C - GS 112 Combo. | TalkBass.com

 

[rufus.K]

Aguilar made a GS112 with an airhead?

Yes, the Ag500 head. The Gs 212 and the Gs112 both came as "combo" units in addition to standalone. The GS212 I've seen around here and there. My 112 is the only combo of that style I've ever seen. I've long removed the head, bei by left with. GS112 with a 2ru airhead. I've often thought about stuffing a straight power amp in it, but in therror end itso more useful as a 112 standalone, thus I threaten to cut it down.

 

[zeb_bass]

Yeah, guess I cant have it both ways... was trying to fish out some rules of thumb. Youre right about off of this. So to divulge, it'd be butchering an Aguilar GS112, and getting closer to the diameter of an Aguilar SL112 port wise. I didnt know port area trades against port depth.

Rufus,
a GS112 is fine just as is! i wouldn´t alter anything at all. don´t believe the hype a gs112 is a fine cab as is and can hang with any other 112. maybe its a bit power hungry and a slight tad mid shy but bass projection is 2nd to none and phenomenal

 

[rufus.K]

Rufus,
a GS112 is fine just as is! i wouldn´t alter anything at all. don´t believe the hype a gs112 is a fine cab as is and can hang with any other 112. maybe its a bit power hungry and a slight tad mid shy but bass projection is 2nd to none and phenomenal

I've played through it for about 7 years, I'm just in a butchery mood.

 

[alexclaber]

Unless the cab was wrongly tuned in the first place, which I doubt, then you're not going to gain anything from trying to increase the port area - it's already sufficient for the volume displacement of the driver in the GS112. If you do add another port you'll need to make it pretty long, and you'll need to lengthen the existing ports, so you'll end up reducing the internal volume of the cab and losing bass response, rather than gaining it.

 

[rufus.K]

Nobody wants to see an Aguilar can die a horrible wheezing death. Okay guys, you've talked me out of it.
As an aside, should talkbass have a speaker/cabinet subheadings of its own, so it's no longer the basted child under the Amps section?

 

[micguy]

Increasing port area raises the resonant frequency of the port. At the port resonance frequency, the driver is somewhat protected from over-excursion by virtue of the loading on the back of the driver (I have a degree in acoustics, sorry if this is a bit geeky). Raising the port tuning doesn't just change the sound, it shifts that "support" frequency range. Net result of more port area is that at the original port tuning frequency, you'll have lost that "support", which means...play enough low notes, and you can rip the speaker's suspension apart with less power than the original design - assuming it was done well to begin with.

So, deciding to leave it as is - probably a good idea. If you want more mid bass, eq the signal electtonically.

 

[rufus.K]

Increasing port area raises the resonant frequency of the port. At the port resonance frequency, the driver is somewhat protected from over-excursion by virtue of the loading on the back of the driver (I have a degree in acoustics, sorry if this is a bit geeky). Raising the port tuning doesn't just change the sound, it shifts that "support" frequency range. Net result of more port area is that at the original port tuning frequency, you'll have lost that "support", which means...play enough low notes, and you can rip the speaker's suspension apart with less power than the original design - assuming it was done well to begin with.

So, deciding to leave it as is - probably a good idea. If you want more mid bass, eq the signal electtonically.

Thanks.
So I'll just cut off the airhead then.

 

[DavC]

i thought the basic port thought was kinda ... size determined freq , length determined volume .. ? but i was playing with various ports back when the ' Apple II-C ' was the hot thing .. !!