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Author Topic: JBL ASB6125  (Read 14694 times)

Ivan Beaver

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Re: JBL ASB6125-Which "standard"?
« Reply #20 on: January 04, 2011, 08:05:14 am »

Jeff Wheeler wrote on Tue, 04 January 2011 01:57

[I'd like to see the specified useful frequency response range actually used for specified peak power testing, without driver damage or outrageous distortion from cone flap.  .


I hate to highjack this thread-as this is a totally different subject and has nothing in common with the origional post.

The problem with that "test" is what to use for the source waveform.  Some say pink noise-OK what crest factor? 6dB-12dB.  That makes a lot of difference.

Or should you use a specific "curve"? Which one?  There are all sorts of standards that the developers each think theirs best describes a music source.  What kind of music.  Metal and classical have very different  freq content.  Most of the standard curves roll off the low freq, yet it is the low freq that is actually putting the strain on the cabinets. Rolling Eyes

Have you ever looked at the typical time vs freq content of a song? I am thinking of starting a thread on that one. but since it is time that produces heating, I would think that it should be considered-but I have not seen any of the "standard" curves that have what looks like it agrees.  Then again-musical styles vary.

If one manufacturer uses one curve and somebody else uses a different one-how do the two compare?

How much distortion is "to much".  

Speaking from a manufacturer perspective, we have been asked to provide certain specific data.  Yet no other manufacturer provides this data.  So somehow the cutomer who requested it is going to use it to "evaluate" the product and then attempt to compare it to a product that does not have that data. Rolling Eyes   How is that possible?  Let's say they see something they don't like.  What about the other product under consideration?  They don't provide the data, so they get a "free pass"? How does the customer know that their data is better or worse-if they don't have it?

There are some things that can be kinda compared.  And then other things are very dependant on the measurement conditions.

I do agree, I would LOVE to have a standard that all manufacturers would have to adhear to.  But I don't think that is gonna happen in our life time.  It is hard enough to get manufacturers to get the spec numbers and their own measured data/graphs to agree.

Even something as simple as the -3dB point in freq response.  It SHOULD be the freq at which the response is 3dB down from the rated sensitivity.  The two HAVE to be tied together-but very rarely  are.  Take a look at the graphs yourself.

Let's say a loudspeaker has a sensitivity of 100dB.  Then the -3dB point would be the freq that is at 97dB on the curve.  SImple as that.  Now if the manufacturer wants a lower cutoff number, then they need to state a lower sensitivity.  Or if they want a higher sensitivity, then they need to be willing to settle for a higher cutoff freq.

You can't have both.

I better stop now before I get in trouble.  I can get very "emotional" when it comes to specs and honesty Laughing  Very Happy
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For every complicated question-there is a simple- easy to understand WRONG answer.

Can I have some more talent in the monitors--PLEASE?

Ivan Beaver
dB Audio & Video Inc.
Danley Sound Labs

Duane Massey

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Re: JBL ASB6125-Which "standard"?
« Reply #21 on: January 04, 2011, 09:52:02 am »

I'm afraid I started the "hijack". Sometimes my pet peeves get the best of me.
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Duane Massey
Houston, Texas, USA

Tim McCulloch

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Re: JBL ASB6125
« Reply #22 on: January 04, 2011, 09:56:34 am »

Duane Massey wrote on Mon, 03 January 2011 18:25

Ivan, that is my point. I can look at a graph and at least see the actual response IF the graph is accurate and legible. Even if it is the standard 1w/1m info it is useful if you have several other boxes with the same info.

You are correct, +/- 3db is only useful if you know what it is referenced to. I'd rather have the graph.

Silas, you are correct. It is not possible unless everyone uses the same standards, and that will never happen.

This is why Flat View sucks.  Duane posted his reply at the bottom of the page, but it is replying to a post by Adam Kane, but as you can see he's responding to posts by Ivan and Silas.
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"Will you stand by me against the cold night, or are you afraid of the ice?" Crack The Sky

Gene Hardage

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Re: JBL ASB6125
« Reply #23 on: January 04, 2011, 10:46:08 am »

http://www.ramsdellproaudio.com/products/subs/680r.htm
http://www.ramsdellproaudio.com/images/products/largehiq/subs/680R_lrg.jpg

2x18 low profile - made here in good ol' FLA just across the state from you.
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Gene SARASOTA SLIM Hardage
http://www.SarasotaSlim.com

Jeff Wheeler

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Re: JBL ASB6125-Which "standard"?
« Reply #24 on: January 04, 2011, 09:33:35 pm »

Ivan Beaver wrote on Tue, 04 January 2011 07:05

Speaking from a manufacturer perspective, we have been asked to provide certain specific data.  Yet no other manufacturer provides this data.  So somehow the cutomer who requested it is going to use it to "evaluate" the product and then attempt to compare it to a product that does not have that data. Rolling Eyes   How is that possible?

This is why I put forth my opinion that any additional data DSL provided beyond their current spec sheets would probably not change the fraction of customers who want an in-person demo before making a decision.  When you are already providing equal or better comprehensive specifications (and underlying methods) than the competition, there is no advantage to doing more.
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Jeff Wheeler, wannabe sound guy / moonlight DJ

Phil Ouellette

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Re: JBL ASB6125
« Reply #25 on: January 30, 2011, 01:17:58 pm »

A church I ran sound for (where I got my start in audio) used a pair of GT-1800 subs for a decade (at least) with no reliability problems.  They were used with pole mounted SOS for half that period and ended being installed in a sub stage pocket after the church moved into their own home.

They are not the most musical sub down low that I have ever heard, but the build quality is decent.  When I first saw them they were powered by an ancient CS800 which was pretty inadequate.  They sounded a lot better after upgrading to a PLX2402 amp.  We got a big sound quality improvement after I reconfigured the system for aux fed subs, we could have gotten a lot better performance with a properly configured DSP crossover, all we had was an analog crossover.

Bottom line, they met the needs and the budget without failures.  I wouldn't hesitate to use them again if they fit the application. That 17" high double 18 sub looks like it would be great for stage pocket installs.
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That's "newbiesque" to my friends.
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