Klipsch RF-82ii vs JBL Studio 580

[lovinthehd]

But how close does putting the bungs in the ports really come to a sealed enclosure? That's why I was looking for examples of similar speakers tested similarly...

 

[Verdinut]

But how close does putting the bungs in the ports really come to a sealed enclosure? That's why I was looking for examples of similar speakers tested similarly...

If the bungs completely block the movement of air in and out of the ports, the box would operate as a sealed enclosure and you would only have one peak in the impedance curve then.

The article in the Australian HiFi Review is complete nonsense. If you block one port, the fb has to increase. Add a second bung to the other port, the fb has to go even higher. In the curves which are printed in the review, there is no increase in the box resonant frequency. That's impossible!

 

[lovinthehd]

If the bungs completely block the movement of air in and out of the ports, the box would operate as a sealed enclosure and you would only have one peak in the impedance curve then.

The article in the Australian HiFi Review is complete nonsense. If you block one port, the fb has to increase. Add a second bung to the other port, the fb has to go even higher. In the curves which are printed in the review, there is no increase in the box resonant frequency. That's impossible!

Just like to see some confirmation other than your own conclusion , no offense. Seems the testing lab in Australia is respectable from what I can tell, so just saying you disagree and that their results are complete nonsense....(at least I assume from past conversation you are only a hobbyist rather than a professional speaker builder or tester).

These aren't solid foam bungs, seems some air can pass, too...I can even see thru them. Just popped a pair into my 590s and turned it up, sound still escapes them...

Will have to dig for some more information in the meantime if you don't have similar tests/speakers to show as examples...

 

[Verdinut]

Just like to see some confirmation other than your own conclusion , no offense. Seems the testing lab in Australia is respectable from what I can tell, so just saying you disagree and that their results are complete nonsense....(at least I assume from past conversation you are only a hobbyist rather than a professional speaker builder or tester).

These aren't solid foam bungs, seems some air can pass, too...I can even see thru them. Just popped a pair into my 590s and turned it up, sound still escapes them...

Will have to dig for some more information in the meantime if you don't have similar tests/speakers to show as examples...

I have been building speaker enclosures for over 50 years and I am knowledgeable about speaker drivers, their parameters and the laws of physics which don't allow any deviations.
I have the proper equipment to test speakers, passive crossover software etc. I started a loudspeaker company several years ago and decided to close it because of competition and costs of setting manufacturing volumes. I have proven my competence with a demonstration of a pair of 3-way bass reflex speakers which I entirely designed including the passive crossover adjustment, voicing etc.
The Association of Montreal Audiophiles (some audiophools in that group too) heard those speakers, and I received applause for their performance. Two of the people in the room told me that my speakers were among the very best that they ever listened to.
I had succeeded in building a high performance three-way system, and when you can succeed in such an undertaking, you cannot be considered as a hobbyist.
Vance Dickason, in his Loudspeaker Design Cookbook, wrote that two-way designs are relatively simple while three-way designs tend to separate the pros from the amateurs.

 

[lovinthehd]

I have been building speaker enclosures for over 50 years and I am knowledgeable about speaker drivers, their parameters and the laws of physics which don't allow any deviations.
I have the proper equipment to test speakers, passive crossover software etc. I started a loudspeaker company several years ago and decided to close it because of competition and costs of setting manufacturing volumes. I have proven my competence with a demonstration of a pair of 3-way bass reflex speakers which I entirely designed including the passive crossover adjustment, voicing etc.
The Association of Montreal Audiophiles (some audiophools in that group too) heard those speakers, and I received applause for their performance. Two of the people in the room told me that my speakers were among the very best that they ever listened to.
I had succeeded in building a high performance three-way system, and when you can succeed in such an undertaking, you cannot be considered as a hobbyist.
Vance Dickason, in his Loudspeaker Design Cookbook, wrote that two-way designs are relatively simple while three-way designs tend to separate the pros from the amateurs.

Thanks for the expansion on your experience. So where do you think the tests by the Australians went awry? Perhaps something to my observation that the lightweight bungs may not make the box behave as a true sealed box? Nothing to the particulars of a 2.5 way design? How about some measurements of similar speakers with two ports with impedance measurements with port bungs as in this test?

I remember @Dennis Murphy also bought a set of these and hasn't commented much beyond something to the effect that there's a lot of engineering involved, but wonder if his measurements were markedly different?

 

[Verdinut]

The bungs you are referring to let pass air. Then that would explain the impedance curves in the article.

I strongly suspect that there isn't much disparity in your hearing perception of your 590's between having bungs installed and none, just based on the published impedance curves. Could you give me more info on your perception with the various configurations?

 

[KEW]

FWIW, in the review, Steve Holding calls them "mesh bungs".

I don't think it is useful, but this is from the manual:

Using the Port Tube Inserts (All models except Studio 520C)
If, due to speaker placement or your room's acoustics, you feel that the speakers produce a bit too much bass output for your taste, you can use the provided port tube inserts to slightly reduce the speakers' output in the 50Hz – 100Hz region. Insert the port tube insert about half way into the port tube opening as shown in the illustration. Be careful not to push the insert through the port tube and into the speaker cabinet. NOTE: The Studio 590 has two port tubes and includes two port tube inserts.

 

[Verdinut]

FWIW, in the review, Steve Holding calls them "mesh bungs".

I don't think it is useful, but this is from the manual:

I'm inclined to agree with you.
If someone wants to reduce the low frequency response, he should simply completely block one or both of the ports and the difference in the frequency response would definitely indicate a noticeable modification of the impedance curve as well.

 

[KEW]

The bungs you are referring to let pass air. Then that would explain the impedance curves in the article.

I strongly suspect that there isn't much disparity in your hearing perception of your 590's between having bungs installed and none, just based on the published impedance curves. Could you give me more info on your perception with the various configurations?

From the article:

Graph 5 shows the effect on impedance of using the port bungs: I’d expect to hear only very minor differences in bass level, based on these measurements.

I must say that I love reading Steve Holdings reviews as they almost always provide more insight explanation into the measurements than other reviews (with the exception of the reviews here which I feel are roughly of the same caliber) as well as insights into the industry (as witnessed by his comment on AMT drivers here - I was wondering why the AMT's started popping up like they did!):

A compression driver is almost unique amongst loudspeakers. Almost all conventional speakers—cones, domes or ribbons—operate directly into the airspace in the room in which the speaker cabinet is placed. (One of the exceptions is the Heil Air Motion Transformer, variants of which are now used by a number of manufacturers, who jumped on it when the German patents expired.)

 

[lovinthehd]

The bungs you are referring to let pass air. Then that would explain the impedance curves in the article.

I strongly suspect that there isn't much disparity in your hearing perception of your 590's between having bungs installed and none, just based on the published impedance curves. Could you give me more info on your perception with the various configurations?

Like I said, I can practically see thru them and this afternoon when I inserted them I put my ear up against them at fairly high volume and while not feeling much air, sound seemed to pass fairly well....not what I'd call sealed. The little I played with the bungs I've just left them out, don't have a too much bass thing, they're not stuffed in corners and are crossed over to subs as well. Might play more in direct mode without subs for the bung thing, will let you know.

 

[KEW]

Like I said, I can practically see thru them and this afternoon when I inserted them I put my ear up against them at fairly high volume and while not feeling much air, sound seemed to pass fairly well....not what I'd call sealed. The little I played with the bungs I've just left them out, don't have a too much bass thing, they're not stuffed in corners and are crossed over to subs as well. Might play more in direct mode without subs for the bung thing, will let you know.

Do you think they were trying to figure out what to do with all the left-over foam they had from their old grills?

 

[lovinthehd]

Do you think they were trying to figure out what to do with all the left-over foam they had from their old grills?

Actually, I think that stuff is denser Bungs not as colorful, tho.

 

[Verdinut]

Like I said, I can practically see thru them and this afternoon when I inserted them I put my ear up against them at fairly high volume and while not feeling much air, sound seemed to pass fairly well....not what I'd call sealed. The little I played with the bungs I've just left them out, don't have a too much bass thing, they're not stuffed in corners and are crossed over to subs as well. Might play more in direct mode without subs for the bung thing, will let you know.

The conclusion is: There are bungs and there are BUNGS!

 

[lovinthehd]

The conclusion is: There are bungs and there are BUNGS!

I definitely have bungs that came with other speakers with denser foam....

 

[Verdinut]

I definitely have bungs that came with other speakers with denser foam....

By definition, a bung is supposed to block the hole in a container. Here the speaker box is the container..

 

[KEW]

By definition, a bung is supposed to block.

Steve Holden called them mesh bungs.

JBL refers to them in the owners manual as "port tube inserts", LOL!

You got to get up "pur-tee early in the morning" to catch Harman with their pants down!

 

[Verdinut]

Steve Holden called them mesh bungs.

JBL refers to them in the owners manual as "port tube inserts", LOL!

You got to get up "pur-tee early in the morning" to catch Harman with their pants down!

For several of the loudspeaker manufacturers, this "BUNG" business is more of a marketing BS.

 

[lovinthehd]

I think I've even seen mention of a rubber plug for a bung, or maybe that was an urban myth with it popping out under sufficient spl....

 

[lovinthehd]

For several of the loudspeaker manufacturers, this "BUNG" business is more of a marketing BS.

Maybe a bit better than the bi-wiring terminals

 

[Beave]

"I need TP for my bunghole."

-another guy with a similar name



(hey lovin, can you post a pic of the JBL bungs - I'm curious to see what they look like.)