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Old 9th June 2008, 09:22   #8221
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the 4" comps @ 5k are unfortunately a bit too expensive and + the rear 6x9's will eat the whole budget, and we're on a very, very tight :( , and even 5" comps up front are a bit overboard. Thinking of something like the GT5's or something in that price range...
The other alternative is to buy a 4" coax and a 6" comp, and use the 6" midbass as a full range in the rear , and the tweeter + 4" coax as the midbass for the LPF output of the crossover up front

Last edited by greenhorn : 9th June 2008 at 09:26.
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Old 9th June 2008, 09:51   #8222
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Quote:
Originally Posted by greenhorn View Post
the 4" comps @ 5k are unfortunately a bit too expensive and + the rear 6x9's will eat the whole budget, and we're on a very, very tight :( , and even 5" comps up front are a bit overboard. Thinking of something like the GT5's or something in that price range...
The other alternative is to buy a 4" coax and a 6" comp, and use the 6" midbass as a full range in the rear , and the tweeter + 4" coax as the midbass for the LPF output of the crossover up front
if you add a tweeter to a 4" coax you will have 2 tweeters up front.
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Old 9th June 2008, 10:32   #8223
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but if i feed the coax the LPF output of the crossover , there wont be any HF content going to the coax's tweeter right , so there will only be one working tweeter up front
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Old 9th June 2008, 10:36   #8224
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Originally Posted by greenhorn View Post
but if i feed the coax the LPF output of the crossover , there wont be any HF content going to the coax's tweeter right , so there will only be one working tweeter up front
you'd have to LPF the 4" at about 3KHz.
also since a 4" has limited bass you'd have to HPF it about 100Hz
does your amp allow you to HPF and LPF the same speaker at 100hz and 3kHz?

do you mean to say that a 4" component+ 6" coax is more expensive than 6" components and 4" coax?

if you intend to use the 6" component woofer in the rear as a full range be warned that
1. it's response will be ragged beyond 3K or so
2. you will get little HF infomation from them since they were degined as woofers and not fullrange drivers

Last edited by navin : 9th June 2008 at 10:38.
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Old 9th June 2008, 10:50   #8225
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Originally Posted by navin View Post
you'd have to LPF the 4" at about 3KHz.
also since a 4" has limited bass you'd have to HPF it about 100Hz
does your amp allow you to HPF and LPF the same speaker at 100hz and 3kHz?
will be using a basic HU (pio 2050 probably) . Is it essential to HPF the coax's ? they run fine in most low end installs without an HPF right.
Quote:
do you mean to say that a 4" component+ 6" coax is more expensive than 6" components and 4" coax?
yes, since for the 4" comps , only illusion/kicker are available, but for 5" and 6" comps , i have a wider and cheaper selection. I know the difference may work out to only 500~1000 rupees , but the budget is that tight. I've sucessfully fought the Ice section budget exceeding demons sucessfully once, and i plan to win again

Quote:
if you intend to use the 6" component woofer in the rear as a full range be warned that
1. it's response will be ragged beyond 3K or so
2. you will get little HF infomation from them since they were degined as woofers and not fullrange drivers
not an issue , since the car is will be self driven mostly.


these are just ideas flying in my head right now. The easiest solution is 4" coax + 6x9's , but then the rears will totally dominate.

the idea which has a good chance of being implemented(provided the installer can pull it off) is 5" comps with spacers in front + 6" coax in the rear. that should have enough bass and be balanced at the same time. But is it doable?

Last edited by greenhorn : 9th June 2008 at 10:52.
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Old 9th June 2008, 16:15   #8226
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Hi,
With lot of help/ideas from Navinji,DerAlte and other members i have made second order butterworth xo.I have used 0.1mH coils (20gauge air core)and 3.3mfd/250v mylar capacitors.The low pass section is working perfectly but the moment i connect inductor in high pass section output drops to about 10-20%.Is it because 0.4ohms resistance of inductor or something else is the problem.I need some input from gurus.

DerAlte
I went to Globe electronics to check ready made crossovers, they had Bolton ( but 8ohms only) and when i saw that i was shocked. There was a bolt and nut used to secure coil to the pcb.will not that bolt act as iron core?

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Old 9th June 2008, 16:55   #8227
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Quote:
Originally Posted by mohang_j
With lot of help/ideas from Navinji,DerAlte and other members i have made second order butterworth xo.I have used 0.1mH coils (20gauge air core)and 3.3mfd/250v mylar capacitors.The low pass section is working perfectly but the moment i connect inductor in high pass section output drops to about 10-20%.Is it because 0.4ohms resistance of inductor or something else is the problem.I need some input from gurus.
Inductance and capacitance values in both sections are same? What drivers are you using? What is the X over frequency?

Quote:
Originally Posted by mohang_j
I went to Globe electronics to check ready made crossovers, they had Bolton ( but 8ohms only) and when i saw that i was shocked. There was a bolt and nut used to secure coil to the pcb.will not that bolt act as iron core?
Living up to the name. Bolt-On.
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Old 9th June 2008, 17:19   #8228
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Originally Posted by Bass&Trouble View Post
Inductance and capacitance values in both sections are same? What drivers are you using? What is the X over frequency?
Yes, Values are same.I am using jbl 506c components.Xoverd at 6000hz.
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Old 9th June 2008, 18:30   #8229
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Quote:
Originally Posted by mohang_j View Post
... i have made second order butterworth xo.I have used 0.1mH coils (20gauge air core)and 3.3mfd/250v mylar capacitors.The low pass section is working perfectly but the moment i connect inductor in high pass section output drops to about 10-20%.Is it because 0.4ohms resistance of inductor or something else is the problem.I need some input from gurus.
Isn't that what an inductor is supposed to do: suppress high frequencies? No, not because of the R component of the coil, but the L itself. The high-pass section is not expected to have an inductor in the series path, unless you want to control the upper roll-off (in which case it is effectively a BP filter). Can you post a schematic of what you have made (like this one)?
Quote:
Originally Posted by mohang_j View Post
DerAlte
I went to Globe electronics to check ready made crossovers, they had Bolton ( but 8ohms only) and when i saw that i was shocked. There was a bolt and nut used to secure coil to the pcb.will not that bolt act as iron core?
Strange are the ways...! Not really - depends on the dia of the bolt. It will definitely affect the L value of the coil to a small degree, assuming it is a 3mm or 4mm bolt, and the coil inner dia is 15mm. I wouldn't be surprised if they have accounted for it, wouldn't be surprised if they haven't! The Globe guys have been around for more than 40 years, and are traditionalists - just don't talk theory with them, they will throw Theraja at you! Only someone like Navin will be able to get through to them (age, language). You just have to check the characteristics with a sweep generator and an oscilloscope to be sure.

Nothing new - this is an age-old practice; the Japanese used to use a plastic bolt 30 years back, but that was before cheap plastic tie-straps or hot-melt glue became popular. Don't be surprised if the piece that you saw is that old.
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Old 9th June 2008, 18:54   #8230
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Quote:
Originally Posted by mohang_j View Post
Yes, Values are same.I am using jbl 506c components.Xoverd at 6000hz.
why have you pushed up the frequency? I suppose you'll get better power handling , but will the response be flat ? originally, they were crossed over at 4k
Quote:
Originally Posted by Bass&Trouble View Post
Living up to the name. Bolt-On.
Nice one

Quote:
Originally Posted by DerAlte View Post
Isn't that what an inductor is supposed to do: suppress high frequencies? No, not because of the R component of the coil, but the L itself. The high-pass section is not expected to have an inductor in the series path, unless you want to control the upper roll-off (in which case it is effectively a BP filter).
I suppose if he can design a second order XO , he should know that the Inductor is wired in parallel with the tweeter to attenuate the LF further. I think it may be some of the usable output in the 4k-6k region which the tweeter is putting out which the inductor may be removing. just a theory though.
Quote:
I wouldn't be surprised if they have accounted for it, wouldn't be surprised if they haven't!
I guess It's one of those bugs which might be a feature

Last edited by greenhorn : 9th June 2008 at 18:58.
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Old 9th June 2008, 22:49   #8231
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Quote:
Originally Posted by greenhorn View Post
but will the response be flat ? originally, they were crossed over at 4k
I will be making xos of 4k,5k also.To check which would sound better.

Quote:
I suppose if he can design a second order XO , he should know that the Inductor is wired in parallel with the tweeter to attenuate the LF further. I think it may be some of the usable output in the 4k-6k region which the tweeter is putting out which the inductor may be removing. just a theory though.
Yes i know Inductor will attenuate LF.

Quote:
Originally Posted by DerAlte View Post
Isn't that what an inductor is supposed to do: suppress high frequencies? No, not because of the R component of the coil, but the L itself. The high-pass section is not expected to have an inductor in the series path, unless you want to control the upper roll-off (in which case it is effectively a BP filter). Can you post a schematic of what you have made (like this one)?
You just have to check the characteristics with a sweep generator and an oscilloscope to be sure.
I don't have one-checked with OM electronics cheapest LCR meter is about 1100Rs.

Yes schematic is same.I have made 2nd order butterworth filter with the help of lalena.com and shavano music online.

I am talking about the total audio output getting attenuated to 10-15% not particular band.

Quote:
the Japanese used to use a plastic bolt 30 years back, but that was before cheap plastic tie-straps or hot-melt glue became popular. Don't be surprised if the piece that you saw is that old.
One i saw was about 6 months old.


One more good news is Universal Electronics (this guy sell all obsolete products at a premium)is still have those Inductors and are made to order.Costs about 35Rs for 0.1mH air core coil.

Now i have opened all coils, i Will rewind them and dip it in varnish lets see what happens.

Last edited by mohang_j : 9th June 2008 at 22:53.
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Old 10th June 2008, 11:20   #8232
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Quote:
Originally Posted by greenhorn View Post
the idea which has a good chance of being implemented(provided the installer can pull it off) is 5" comps with spacers in front + 6" coax in the rear. that should have enough bass and be balanced at the same time. But is it doable?
very doable.

Quote:
Originally Posted by mohang_j View Post
I have used 0.1mH coils (20gauge air core)and 3.3mfd/250v mylar capacitors.The low pass section is working perfectly but the moment i connect inductor in high pass section output drops to about 10-20%....There was a bolt and nut used to secure coil to the pcb.will not that bolt act as iron core?
for a standard electrical Xo at 6kHz for 4 ohms drivers
Capacitors
C1 = 4.7 uF
C2 = 4.7 uF
Inductors
L1 = 0.15 mH
L2 = 0.15 mH

Since both your inductors are the same check the inductor you have in parallel with the tweeter by switching with the other (working) inductor.

another option is to add a 4ohm resistor in series with the inductor that is in parallel with the tweeter. the series resistor will only compesate for the rising impedance of the tweeter. try this and post your results.

Quote:
Originally Posted by mohang_j View Post
Yes, Values are same.I am using jbl 506c components.Xoverd at 6000hz.
Quote:
Originally Posted by Bass&Trouble View Post
Inductance and capacitance values in both sections are same? What drivers are you using? What is the X over frequency?
B&T, mohan is building a standard XO (a XO that does not compensate for the freq response roll off of the drivers) at the nominal impedance of the drivers.

mohan, when you design a XO yo must note that the driver has it's own roll off and that the impedance at XO freq may not be the same at the nominal impedance

Quote:
Originally Posted by mohang_j View Post
Yes i know Inductor will attenuate LF.
I am talking about the total audio output getting attenuated to 10-15% not particular band..
energy is above 6K is 10% of total Energy in a musical signal. Listen to the system with both sections of the XO connected dont listen to each section (LP or HP) individually, not yet, you wont get the right picture.
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Old 10th June 2008, 11:26   #8233
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Quote:
Originally Posted by DerAlte View Post
Nothing new - this is an age-old practice; the Japanese used to use a plastic bolt 30 years back.
and the yanks used brass, i am talkig about a time when RCA was an American company that made tubes and radios.
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Old 10th June 2008, 11:53   #8234
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Hi,

What all options are available for a Subwoofer and Amplifier for a budget of 10-12K
My preference is tight Bass.
And I would also like to drive the existing front components from the Amp.

Also Will a kenwood 8401 or 8404 amp sufficient for driving a ID12 D2 v.3, or it won't be able to do justice to sub?
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Old 10th June 2008, 11:59   #8235
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Quote:
Originally Posted by hrsraghav View Post
Hi,

What all options are available for a Subwoofer and Amplifier for a budget of 10-12K
My preference is tight Bass.
And I would also like to drive the existing front components from the Amp.

Also Will a kenwood 8401 or 8404 amp sufficient for driving a ID12 D2 v.3, or it won't be able to do justice to sub?
I have a similar query. I am looking for a 'budget' sub (sealed box: for SQ and not a very boomy bass). This I intend to drive through 2 bridged channels of an amp (as the remaining two will drive the front comps).

So what all options are there for sub+amp around 10-12k?
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