Hello, please, I need to have an idea (even if it is approximate) of the compliancy (Qts) of this speaker.
I've always wondered how a particular speaker can work efficiently in the boot or on the door of the car.
I have never seen published compliancy values (in car speakers of any brand), is it supposed to be low or high?
I have not found information on the web, can anyone here help me ?
https://www.vzdy.sk/buxus/docs/down...files/catalog_-_jbl_car_2006_(english_eu).pdf
Low-Q design – For improved bass
extension and better transient response
in infinite-baffle applications (doors and
rear package tray).
I've always wondered how a particular speaker can work efficiently in the boot or on the door of the car.
I have never seen published compliancy values (in car speakers of any brand), is it supposed to be low or high?
I have not found information on the web, can anyone here help me ?
https://www.vzdy.sk/buxus/docs/down...files/catalog_-_jbl_car_2006_(english_eu).pdf
Low-Q design – For improved bass
extension and better transient response
in infinite-baffle applications (doors and
rear package tray).
No,no,no !
I just want to modify a box that I made a few years ago. But, as I now have more knowledge and learned how to use and interpret WinIsd, I want to do something more accurate, although it was calculated at the time with the available formulas, I chose a high Qts value by deduction, just because I noticed that this rubber suspension of the GTO627 is very hard...
The enclosure is mainly for the very low frequencies. If you're not trying to get those low frequencies, the enclosure isn't very important. The damping material in the enclosure is more likely to make a noticeable difference.
Many small car speakers are used in what is essentially an infinite baffle.
The low frequency response in a car is boosted significantly by the transfer function of the cabin of the vehicle. You won't get that in a home environment.
Many small car speakers are used in what is essentially an infinite baffle.
The low frequency response in a car is boosted significantly by the transfer function of the cabin of the vehicle. You won't get that in a home environment.
Yes, I know everything you say, and I appreciate your advice, thank you.
For really low frequencies, I'm working on this project:
Materials for cylindrical subwofers ?
With respect to the reason that made me build these cabinets, it was because at the time I decided not to modify (spoil?) my car to improve its sound. I see your avatar and I understand that it is your "strong", then you will understand me. I hurried and bought the speakers first convinced that I would not have problems with the installation in the trunk. It was not like that, unfortunately. They were about a year, on a shelf waiting for their destination.
And I went back again buying two identical extra speakers for the front doors. Until it was time for installation, and the surprise was the speakers in the trunk were too big for accommodation, the original speakers have a much smaller magnet than the GTO627. But all this is past history.
So I decided to give them a different use (and entertain myself a little) by building a box with a speaker for each one.
I'll tell you that I liked the sound obtained with my DIY work better than the sound of an Infinity SM-65, with which it was compared exhaustively) The titanium tweeter of the car speaker JBL definitely left behind the Infinity Polycell .....
And with some basic calculations and a lot of trial (trial and error), I also managed to get the middle / bass sector to have nothing to envy to the Infinity 2 way. I worked on the tuning so that the bass was a bit drier than the Infinity, they were a bit "boomy". A matter of taste, perhaps.
But now I want to make use of the other two remaining speakers ....
I hope you understand, my English is quite primitive, and San Google is my permanent help.
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With satisfaction I found that the values of similar Focal speakers have values of QTS that confirm the value of 0.860 for JBLGTO627, used for my previous calculations, this data was obtained from a russian web page, someone had taken the work of measuring the parameters TS of 627, I now confirm then that he did a good job.
I will leave some photos of the modification progress soon.
It will be a D'Appolito configuration (pseudo), 2 identical speakers per box, the cabinet is 25 liters, with the virtual increase of about 20% of polyfill will reach 30 liters.Approximate. (I will eliminate fiberglass, it's time to modernize and protect my lungs)
Brand JBL Focal Focal Focal Focal Focal
Model GTO627 130 200 170 165 130
Size 6.5 4 8 6,8 6.5 4.5
Qts 0.86 0,799 1,1 0,68 1.0 0.779
Thanks Zung !
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Hey, zung .... it's really hard to believe that the original speakers of a Merc S204 are so bad ..... could you tell me what brand they are ?
And the tweeter of the JBL Club 750t is not the same as the JBL 627 .... I think you are comparing pears with apples ... look, they are both fruits, but they have very different flavor
!
Attachments
The front panel (baffle) must be replaced to accommodate the 2 speakers there. Win Isd makes a small difference in favor of the sealed cabinet, so there will be no tuning tubes this time.
Neither will it be necessary to design the xover, it will remain the same, it has behaved
well before.
The loss of SPL going from vented to sealed will be compensated by the extra speaker .
Unfortunately this Skill router machine has very little vertical travel, so I must finish the job by hand. But it will be much easier, 3/4 of the thickness of the baffle was devastated
Neither will it be necessary to design the xover, it will remain the same, it has behaved
well before.
The loss of SPL going from vented to sealed will be compensated by the extra speaker .
Unfortunately this Skill router machine has very little vertical travel, so I must finish the job by hand. But it will be much easier, 3/4 of the thickness of the baffle was devastated
Attachments
Do you have an RV or something BIG?
Me I'm just trying to achieve the least bad within the available space and a minimum of fuzz!
Regarding the Merc's, I'm not sure they care much about their luxury image anymore. The good folks over at mbworld.org say the speakers cost a dollard from China. My car is about 5K USD cheaper than a similar but lower spec'ed Volkswagen (less hp, no 4 wheels drive). The VW has better finish, the Merc drives better.
Attached is a REW response of my current mess, with the JBL tweeters from 8KHz and the stock speakers, and the mike on my left & right shoulder. Not too visible but very audible are 2 resonances at 1KHz and 7KHz.
Attachments
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I think there is a confusion here, maybe I should move this thread ... I leave the restlessness to the mod.
My limited English can cause confusion, or maybe I do not clarify this before.
A thousand apologies anyway.
These 2 DIY cabinets will be returned to my daughter, she was delighted with my gift but I took them to add one more speaker in each baffle, they had no greater utility for me, and since they are 2 Ohms nominal, they had attached an R in series to protect the amplifier. It will be replaced by an identical serial speaker, which, although it is not correct because it affects the DF and if one fails, the other will fail, etc. etc. It will not be a problem when listening.
Having said that, I will continue contributing in this thread until finishing the construction, but it is clear that this is not destined to go in the trunk of my car ...
One more time for OT:
The good audio I enjoy in my living room, I have no interest in doing it in my car, with the system that came from the factory is enough ..
Mainly, because here it is very dangerous, people drive unscrupulously, reading and writing MSN on their mobile phones or watching videos on the screen ......... not only on urban streets, also on highways and fast lanes ! .....
It becomes imperative to have all the senses alert to take care of the idiots at the wheel!
We have an index of mortality from automobile accidents among the highest in the world.
Sad record ....
My limited English can cause confusion, or maybe I do not clarify this before.
A thousand apologies anyway.
These 2 DIY cabinets will be returned to my daughter, she was delighted with my gift but I took them to add one more speaker in each baffle, they had no greater utility for me, and since they are 2 Ohms nominal, they had attached an R in series to protect the amplifier. It will be replaced by an identical serial speaker, which, although it is not correct because it affects the DF and if one fails, the other will fail, etc. etc. It will not be a problem when listening.
Having said that, I will continue contributing in this thread until finishing the construction, but it is clear that this is not destined to go in the trunk of my car ...
One more time for OT:
The good audio I enjoy in my living room, I have no interest in doing it in my car, with the system that came from the factory is enough ..
Mainly, because here it is very dangerous, people drive unscrupulously, reading and writing MSN on their mobile phones or watching videos on the screen ......... not only on urban streets, also on highways and fast lanes ! .....
It becomes imperative to have all the senses alert to take care of the idiots at the wheel!
We have an index of mortality from automobile accidents among the highest in the world.
Sad record ....
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Attached sim Win ISD of the modification
The peak above the line of 0 db is because the box of 21 liters is too small for 2 speakers, as you can see with a single speaker is flatter.
Can be reduced electronically, with a capacitor? Does anyone know how to calculate it ?
The peak above the line of 0 db is because the box of 21 liters is too small for 2 speakers, as you can see with a single speaker is flatter.
Can be reduced electronically, with a capacitor? Does anyone know how to calculate it ?
Attachments
Any suggestions?
The speaker GTO627 is a 2-way coaxial, has a built-in crossover that is calculated for a crossing much higher than the peak that I would like to attenuate, between 120 and 300 hz
I've been studying this but I can not clarify things ...
ERSE - Crossover Calculator - Second Order 3 Way