[greenhorn]

JBL 4" coaxes have a sibilant metallic sound, especially off of a Pio HU

personally i find that combo atrociously issibilant. Unfortutnately
1. They're among the more vfm deal's out there
2. most dealers have them in stock.

If it were me I would have bought an alpine CDE 100EUB (7k), Hertz dieci coaxes all around (2k + 4k) + MDF tray (1k) and some damping around the front coax install location . perhaps a grey market Kenwood HU if the budget was going a bit overboard

[aditya@pune]

Gurus - need help. don't scold me for opting a bad installer. Now i need to correct it how ?
I repalced stock 2-DIN system of Optra with Balupunkt. Now HU dimension is small. Hence gaps. Even the kit came with HU is not fitting correctly. Now what? Attaching the pic so that you can have a view.
Other problem - developed since last one week. When i switch on the car HU starts. But if i have to off the HU its not taking input from on-off knob, rather it's taking input from Menu button ( Beside the eject cd button). I can switch on - off HU with the Menu button but there is no way if i don't want the HU to start with the engine. What went wrong in this case?

[srishiva]

Found that Vento has 8 ohm speakers. Now most of what you get outside are 4 ohms. Since it increases the current drawn, would that have any impact on the HU amplifier or it should be within the tolerance limits (with all the fire incidents out there)

[greenhorn]

nope, dont worry about fire, but the amp would certainly be a bit strained. Most solid state amps should manage 4 ohms without fuss, but just in case, dont push the HU volumes too much.
If you absolutely want to be safe, (especially if you are planning to use the same type of speakers in teh front and back) you could wire them in series, and in the process lose the ability to control the front/back volume distribution

[Bass&Trouble]

Originally Posted by srishiva

Found that Vento has 8 ohm speakers. Now most of what you get outside are 4 ohms. Since it increases the current drawn, would that have any impact on the HU amplifier or it should be within the tolerance limits (with all the fire incidents out there)

How did you find that out? If you're referring to OEM speakers of the Vento, I find that a bit hard to believe though I haven't verified myself. With the puny OEM head unit's amp, an 8 ohm speaker would hardly produce any reasonable output.

And no, there cannot be any fire. Faced with an 8 ohm load, the amplifier would put out far lesser power rather than more. Even if something untoward has to happen, the head unit is wired through a fuse.

Originally Posted by greenhorn

If you absolutely want to be safe, (especially if you are planning to use the same type of speakers in teh front and back) you could wire them in series, and in the process lose the ability to control the front/back volume distribution

That would make it 16 ohms.

[greenhorn]

Originally Posted by Bass&Trouble

That would make it 16 ohms.

whoops I meant connect two (on each side) in series

[Bass&Trouble]

Originally Posted by greenhorn

whoops I meant connect two (on each side) in series

You DEFINITELY mean parallel!

[Nishant B]

I am in dilemma and need some help urgently. I am in US for some work and have ordered Kappas 50.9 CS component rated 85W*2 at 4 ohms.

I am now looking for an 2 channel amplifier to power these and was wondering whether an amp with lower power rating (75*2 at 4 ohms and 100*2 at 2 ohms) would suffice for the time being as I am low on money now and have tons of other shopping to do.

I am looking at this amp Sound Ordnance™ M-2100 2-channel car amplifier — 75 watts RMS x 2 at Crutchfield.com right now but would be happy to have any suggestion for less than $100.

Thanks a lot in advance

[greenhorn]

Originally Posted by Bass&Trouble

You DEFINITELY mean parallel!

Damn! I'm not sure why I keep doing confusing them. I didnt get 100 in my 10th board physics exam because for some reason I thought two resistors were in series even though the picture obviously showed they were parallel.

[navin]

Originally Posted by aditya@pune

Other problem - developed since last one week...I can switch on - off HU with the Menu button but there is no way if i don't want the HU to start with the engine. What went wrong in this case?

It seems like the Optra OEM HU is larger than 2 DIN. The Blaupunkt trim plate would buy you 2-3mm at bet. This gap looks more than that. I dont see any option other than fabricating a custom trip plate for the Optra. There are gaps on all 4 sides from what I can see.

As far the on-off issue is concerned to be honest I did not understand the query. If your HU comes on when you turn then engine on maybe yuor installer are wired the power wires incorrectly.

Originally Posted by Nishant B

I am now looking for an 2 channel amplifier to power these and was wondering whether an amp with lower power rating

There will be no problem. Power ratings are only indicative not absolute. Most cases the woofer's excursion capablity is the real limitation.

[aditya@pune]

Originally Posted by navin

As far the on-off issue is concerned to be honest I did not understand the query. If your HU comes on when you turn then engine on maybe yuor installer are wired the power wires incorrectly.

Thank your Navin Sir for trim suggestion. Even i thought so, now need to find someone who can make a custom trim.
For On Off problem : this was working perfectly till last week. I installed 2 months back. All of sudden it developes this issue. Is it possible that wiring goes on toss all of sudden? Big doubt i have is how come it's getting on - off from the menu button. Is it some software/Virus issue of the system? Now i am not using the system, will be taking the car to installer for checking the wiring. Not able to find a good installer who can do the only wiring part in Pune.

[navin]

Originally Posted by aditya@pune

Thank your Navin Sir for trim suggestion. Even i thought so, now need to find someone who can make a custom trim.
For On Off problem : this was working perfectly till last week. I installed 2 months back.

Maybe not a virus, maybe some electronic part failure. That is what I suspect.

[srishiva]

Originally Posted by Bass&Trouble

How did you find that out? If you're referring to OEM speakers of the Vento, I find that a bit hard to believe though I haven't verified myself. With the puny OEM head unit's amp, an 8 ohm speaker would hardly produce any reasonable output.

And no, there cannot be any fire. Faced with an 8 ohm load, the amplifier would put out far lesser power rather than more. Even if something untoward has to happen, the head unit is wired through a fuse.
.

The Vento speakers are indeed 8 ohms. Now when you replace it with 4 ohm ones, the current will be more. The amp in the HU needs to handle this.

[DerAlte]

Originally Posted by aditya@pune

... I can switch on - off HU with the Menu button but there is no way if i don't want the HU to start with the engine. What went wrong in this case?

Originally Posted by navin

... If your HU comes on when you turn then engine on maybe yuor installer are wired the power wires incorrectly. ...

Definitely wrong wiring. @aditya@pune, please help your installer correct it by getting the red and the yellow (could be yellow/red) wires from the harness wired correctly to the HU by reading the terminal diagram on the HU (would be in the manual too). Red goes to ACC in the rear left bottom most connector, and the Yellow (or yellow/red) goes to BAT+. If the ACC wire is connected to the battery directly (as it looks like in your case), you can operate the HU even without turning the key on, since the ignition switch is bypassed.

Originally Posted by Nishant B

...I am looking at this amp Sound Ordnance™ M-2100 2-channel car amplifier — 75 watts RMS x 2 at Crutchfield.com right now but would be happy to have any suggestion for less than $100. ...

Don't bother buying a 2-channel amp from US. You will get a decent Sony / Pioneer 4-channel amp in India for around the same price, with warranty!!! A Kenwood or JBL will cost about 1K more. And please don't worry about the power rating unless you want to operate it like a PA system.

[aditya@pune]

Originally Posted by navin

Maybe not a virus, maybe some electronic part failure.

Originally Posted by DerAlte

Definitely wrong wiring. @aditya@pune

Thank you Navin Sir and DerAlte. Will talk to installer with your suggestion and comeback if something new comes up.

DerAlte: Can you suggest where i can get the custom trim for my system? If you can source one in Banglore I can collect from there. I will be in Banglore next week.