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Such thing as Ported or Sealed specific speakers?

Barbaric.Eric

Barbaric.Eric

Jan 30, 2015
511
701
Moosehat, Saskatchatoon
bigdurty.bandcamp.com
#1
Hi everyone,
I have a question for the speaker experts: Is there such thing as a speaker designed specifically for sealed cabs or speakers designed specifically for ported cabs? Or is each speaker capable of either application and the only difference is cabinet design?


I'm asking because I just scored an empty Ampeg 410he shell for cheap and I'd like to put my Fender Rumble 410 V1 guts into it (to match my SVT CL head visually, plus the head will sit in the foot holds more securely... also it would then be a 4ohm 4x10 :woot:).

The Ampeg shell is sealed, but the Fender is ported along the bottom front edge. The Rumble is equipped with "Fender Special Design Speakers" but it's tough to dig up any info on these online so I'm not sure how they would perform in a sealed cabinet.

4.JPG 5.jpg

Thanks!
 
#3
CL400Peavey said:
This will end poorly. There are differences between speakers best suited for ported cabs, and those suited for sealed cabs.

You should look at 4 of these:

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Click to expand...

Very interesting, I was actually expecting to hear the opposite. Would I be looking at possibly damaging the speakers themselves by swapping to a sealed cab or just not achieving optimal volume and frequency depth?

I really wish new speakers were an option but I would be looking at $533 CAD for 4 Legends before taxes, shipping and handling. I just can't justify putting that into a used $40 shell.
 
#4
Depends on a lot of factors, none of which you will be able to provide most likely. The speakers may be damaged depending on their specs, and your performance may suffer from slightly, to terribly.

So you may end up with a cab that sounds like dog turds, or one that doesnt sound like anything.
 
#5
Giving it a try and being careful with volume and the bass-pot should give you an answer without damaging anything.

I would expect the sound to be not as good as it could be with the right speakers, but as far as I understand the box being closed results in more damping which would rather help in not damaging the speakers.
 
#6
guitarrophobe said:
Giving it a try and being careful with volume and the bass-pot should give you an answer without damaging anything.

I would expect the sound to be not as good as it could be with the right speakers, but as far as I understand the box being closed results in more damping which would rather help in not damaging the speakers.
Click to expand...

Not necessarily. Depending on the speakers they may need the air flow for cooling. So a sealed cab may cause the coils to overheat and be damaged.
 
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#7
Thanks for the input fellas! This is helpful, since I'm still very green when it comes to speaker knowledge.

I'd like to still give it a shot, just for the sake of tinkering and learning, and everything can always be reinstalled in the Fender as long as nothing is damaged in the process... but worst case (aside from a fire) a Fender Rumble won't fetch much around these parts right now anyways so I haven't much to lose.

@CL400Peavey, you make a good point about heat though, I haven't considered that yet. I might connect the Rumble to my SVT-CL and push it hard for a while and see if I can feel any heat resonating from the port, I've never noticed any heat from that cab before.... but than again, I've never gone looking for it hah
 
#11
FWIW, I know of several people, including myself, who have plugged ports on various cabinets. I've never blown or overheated the speakers I've tried this with. Tonally, it's a grab bag. A couple of cabs I've had great results, most just lose volume and become muted. Recently plugged the ports on an Ampeg 610hlf. Ran fine @ 4 ohms with 500 or 700 watts for a few weeks.
 
#12
blubass said:
FWIW, I know of several people, including myself, who have plugged ports on various cabinets. I've never blown or overheated the speakers I've tried this with. Tonally, it's a grab bag. A couple of cabs I've had great results, most just lose volume and become muted. Recently plugged the ports on an Ampeg 610hlf. Ran fine @ 4 ohms with 500 or 700 watts for a few weeks.
Click to expand...

That's reassuring to hear. Becoming more "muted" could be a pro in this case because the Fender is incredibly bright (too bright!). The transition into the Ampeg shell would essentially be the same as plugging the ports in the Fender, they seem to be similar cabs although the Ampeg does have slightly more cubic volume internally because of its depth, even with the Fender port taken into account along the bottom of that cabinet.

Thanks for your input!
 
#13
Barbaric.Eric said:
That's reassuring to hear. Becoming more "muted" could be a pro in this case because the Fender is incredibly bright (too bright!). The transition into the Ampeg shell would essentially be the same as plugging the ports in the Fender, they seem to be similar cabs although the Ampeg does have slightly more cubic volume internally because of its depth, even with the Fender port taken into account along the bottom of that cabinet.

Thanks for your input!
Click to expand...

Yeah, it's really a try it and see thing. We can explain generic tonal differences but doing this on a DIY level is a great way to get a better understanding of the benefits and drawbacks of ported vs sealed designs. I did it so I could learn, and it was a valuable experience that helped me more accurately pinpoint what I liked about my tone, and what I wanted to change.

Paper specs are great and shouldn't be taken for granted, but often people regurgitate this information without any other research. There's plenty of things on paper that shouldn't work, the calculations just don't add up, but in reality they do work just fine. I say swap the speakers and go for broke. Work with the volume low and slowly increase it, stopping and listening to any issues with the speakers. They usually don't pop before giving you plenty of warning signs using this method.

Worst case scenario and highly unlikely.... you blow a speaker or two

Favorable scenario.... the swap works brilliantly and you just created a best of both worlds cab that will give you years of trouble free service

Most likely scenario.... There are awkward eq issues with the cabinet not being tuned to work with those speakers. You only wasted the amount of time it took to do the swap.

Best of luck!!!
 
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#14
CL400Peavey said:
Not necessarily. Depending on the speakers they may need the air flow for cooling. So a sealed cab may cause the coils to overheat and be damaged.
Click to expand...
Almost completely unlikely if not impossible. Urban myth based on a tiny bit of truth.

The biggest problem is the increased potential of mechanical damage.
 
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#16
blubass said:
Yeah, it's really a try it and see thing. We can explain generic tonal differences but doing this on a DIY level is a great way to get a better understanding of the benefits and drawbacks of ported vs sealed designs. I did it so I could learn, and it was a valuable experience that helped me more accurately pinpoint what I liked about my tone, and what I wanted to change.

Paper specs are great and shouldn't be taken for granted, but often people regurgitate this information without any other research. There's plenty of things on paper that shouldn't work, the calculations just don't add up, but in reality they do work just fine. I say swap the speakers and go for broke. Work with the volume low and slowly increase it, stopping and listening to any issues with the speakers. They usually don't pop before giving you plenty of warning signs using this method.

Worst case scenario and highly unlikely.... you blow a speaker or two

Favorable scenario.... the swap works brilliantly and you just created a best of both worlds cab that will give you years of trouble free service

Most likely scenario.... There are awkward eq issues with the cabinet not being tuned to work with those speakers. You only wasted the amount of time it took to do the swap.

Best of luck!!!
Click to expand...
The math does indeed work when it comes to describing the large signal behavior that governs the possibilities for damage to the drivers.

Totally, not as much as personal taste is different for different players.
 
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#18
agedhorse said:
The math does indeed work when it comes to describing the large signal behavior that governs the possibilities for damage to the drivers.

Totally, not as much as personal taste is different for different players.
Click to expand...


I agree with you. I was referring to things in general not working out on paper, but actually working in real life. My go-to example is the M2 50 cal machine gun. However, in this instance I meant that even if the speakers aren't ideal for use in that cabinet, the sound the cab produces may still be pleasing to the user.
 
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#19
A smaller sealed cab should help limit max excursion. The speakers is better damped with the trapped air acting as a spring against The cone movement.
The rf of the speaker is raised in a sealed cab. So speaker RF value and Q value can give an idea of The behavior.

In an old early 70s ampeg 810. Those 30-35w alnico speakers would probably die att little earlier placed in an open cab when played loud with an svt300. Its The same with 25w greenbacks in a marshall 4x12. They tend to go loose and undefined in an Open back cab
 
#20
Going from a ported cabinet to a sealed on, I would expect to have a lot fewer problems than the other way around potentially. Sealed cabs essentially have a strong mechanical load on the cones that has to be compressed. Ported cabs still have a mechanical load, but it only has to be pushed out through the ports. So if the drivers were designed in such a way to fully take advantage of that strong mechanical load in a sealed cab, in a ported one they might not be damped enough to A) get good sound out of them and B) to easily prevent damage from over-excursion.

And yeah, the cooling concern seems a bit ridiculous, as if sealed speakers have some special fancy passive cooling that works in a closed environment.
 

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