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Discussion Starter #1
These JBL subs are going pretty cheap dual 2 ohm Voice coils 3 inches in diameter.

Is there any REAL difference in the graphs given room gain and EQ's that are available?

The box is much smaller with JBL and the driver is cheaper.

They seem like nice subs. If someone can explain the reason the Shiva is so popular over other options please let me know (I am a HomeAudio beginner)

Thanks!


 

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How cheap?
 

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To make the graphs easier to see, under the "Plot" tab select "2" as the width. To compare 2 subs, use the SPL graph and also the cone excursion graph with the appropriate High Pass filter applied under the "EQ/Filter" tab.

The spec sheet I looked at state the P1224 is dual 4 ohm coils.
 

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Discussion Starter #8 (Edited)
With the Shiva-X's greater power handling and double the Xmax, it has 7 db more output at 20 hz compared to the JBL P1222.
Interesting. The JBL is rated at 400/800 and I would think that would be pretty close considering that figure changes based on the enclosure.

Also is the 27mm for the Shiva-X the Xmax or Xmech?

The JBL has the 1watt/1meter advatage by (calculated by me LOL) 84.4 to 91dB

So if the Shiva-X does indeed have the much larger X-max than the JBL does this ability not hurt it in the sensitivity range making it not as loud int he real world? Say if both were fed 300 watts?
 

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With the Shiva-X's greater power handling and double the Xmax, it has 7 db more output at 20 hz compared to the JBL P1222.
This is of course presuming both drivers are actually linear at high power/excursion which is an unlikely case.

Further explanation taken from the WinISD tutorial:

While modeling at low frequencies is fairly accurate there is one large, erroneous, assumption made. That is that the driver being modeled will act in a linear fashion at moderate to high SPL/excursion. This simply is not the case for the majority of the drivers on the market. Of course, one specifically chooses a well designed, high quality unit, that has been proven via credible measurement to have these attributes that is a different case.
 

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Wouldn't double xmax be a 3db difference? :scratch:

I guess the answer to your question would depend on the price difference. As for linearity vs excursion, this is dependent on the motor design. The shiva, if I remember right, has a very good motor design for more linear travel throughout its range. I don't know anything about that JBL
 

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The Shiva-X, Tempest-X and Maelstrom-X are all fairly linear with big power handling, relatively low distortion and big xmax.
Don't know anything about the JBL.
 

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The shiva, if I remember right, has a very good motor design for more linear travel throughout its range. I don't know anything about that JBL
The Shiva-X, Tempest-X and Maelstrom-X are all fairly linear with big power handling, relatively low distortion and big xmax.
Don't know anything about the JBL.
While it is true that these units are marketed as highly linear devices, I am aware of no actual credible measurements of any of these drivers. Such statements cannot be accurately made without actual said credible evidence such as measurements offered by Ilkka.
 

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This is of course presuming both drivers are actually at high power/excursion which is an unlikely case.
That point can't be debated. But for the majority of people looking for low end output in a HT sub, it's irrelevant. The response from the DIY sub builders is ""Wow, I can't believe what I was missing! Sounds great!"". I've yet to hear a negative comment regarding "linearity" in a HT sub.
 

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That point can't be debated. But for the majority of people looking for low end output in a HT sub, it's irrelevant. The response from the DIY sub builders is ""Wow, I can't believe what I was missing! Sounds great!"". I've yet to hear a negative comment regarding "linearity" in a HT sub.
True, people don't complain about lack of linearity, but they complain about lack of LF response when the subwoofer is pushed during a dynamic scene or a compressed sound at high SPL etc....

From my observations it seems rare that people actually complain about the specific issue, but the audible representation of that issue.

Linearity and low end output aren't always mutually exclusive though, correct?
Not necessarily. Linearity refers to a drivers ability to maintain it's response curve at low SPL [excursion/power input] and high SPL [excursion/power input]. So, take a horn loaded subwoofer which are typically highly efficient. Such a design would have minimal compression in high SPL/low frequency if designed properly for such an application due to minimal power/excursion requirements. In more typical ported or sealed situations the drivers are required to do more work to achieve high output and are typically required to be linear, but the cabinet must be designed properly to take advantage of such an attribute.

The main point of the original post I made is to remind those who are modeling a driver that just because it models well does not necessarily mean quality performance when pushed [even to half its rated xmax/power rating], especially relative to another unit. Evidence of a specific drivers linearity through actual measured performance is required to ensure modeling is accurate.

That being said in such a case between the two drivers being examined I would likely recommend the Shiva-X. If the driver choice could be expanded I would recommend a proven linear device.
 
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If its worth anything I believe my buddy has the JBL sub you are referring to. I have the Shiva-X with the BASH 500 watt amp. He has the same amp and 5+ cu./ft enclosure tuned 19 Hz. I built the 4.9 cu./ft enclosure tuned to 17 Hz. The sound and SPL of my Shiva are a good 20% better than his. My room is 100 cu./ft larger with more acoustic panelling. All things considered every body including his wife much prefer my sub.
Don't know if this is of any value to anyone but thought it might help. The Shiva has been the best 12 I have heard. Although I have never herd a Sound Splitter sub. Just my 2% of $1
 

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While it is true that these units are marketed as highly linear devices, I am aware of no actual credible measurements of any of these drivers. Such statements cannot be accurately made without actual said credible evidence such as measurements offered by Ilkka.
Couldn't have said it better myself. :yes:I keep seeing people comparing 2 products, of which they have no personal experience with either and there is no credible testing data to base a better informed opinion with. Remember that people selling something will always be biased to their own product and that bias may show up in many areas, whether it's intentional or not.
 
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