[navin]

Originally Posted by Sam Kapasi

I should be spanked.

Guys dont fall into this trap. Sam actually enjoys being spanked.

[Invinsible]

Originally Posted by Mi10

Thank you Sam ji. I had this doubt for quite sometime now.

Planning this kinda setup for my Swift.

Provided the gains on the both front 2 channel and rear are set accurately. If not that sub ain't gonna have longer life.

[Rajith]

Samji,
Im confused.
I am having following kit and cant afford to invest more, help me to get the best out of this for my Bolero please.
1)JVC DVD with Bulit in Blue tooth HU i think 7404.
2)2 OE rear speaker.
3)2 front boston 4 inch 240 watts speaker.
4) 2 pioneer tweeter
5)2 pioneer oval speaker blue cone.
6)1 dual coil pioneer 1400 sub with 50ltrs box.
7)4 channel amp 2 nos from jbl and sound stream each.
8)Necvox LCD.
Rajith

Originally Posted by Sam Kapasi

What about your speakers? Components? Coaxials? Where are you going to get the "shrill" from?

A dual 4Ω woofer is tricky. Put it in series and you have 8Ω, the amplifier will underperform. Put it in parallel and it turns into 2Ω, which is ok for a single channel amplifier, but not ok if you connect it in bridged mode.

The thing is, that in bridged mode, each individual channel "sees" half the impedance. So most amplifiers require the minimum impedance to be 4Ω in case of bridging. (so that each individual channel only sees 2Ω and not 1Ω)

If I was you, I would use an entire 4 channel amplifier for that woofer. Bridge 2 channels into one 4Ω coil and the other 2 channels to the other 4Ω coil.

Then I'd use another 4 channel amplifier to drive the 4 speakers. So yes, you should use both your JBL as well as your soundstream amplifier.

Now tell us what speakers you want to use Mr. Shrill.

[Sam Kapasi]

Originally Posted by Rajith

Samji,
Im confused.
I am having following kit and cant afford to invest more, help me to get the best out of this for my Bolero please.
1)JVC DVD with Bulit in Blue tooth HU i think 7404.
2)2 OE rear speaker.
3)2 front boston 4 inch 240 watts speaker.
4) 2 pioneer tweeter
5)2 pioneer oval speaker blue cone.
6)1 dual coil pioneer 1400 sub with 50ltrs box.
7)4 channel amp 2 nos from jbl and sound stream each.
8)Necvox LCD.
Rajith

Throw the tweeters away.

Use the boston 4" front, assuming the bolero accommodates 4" fronts. Use the blue ovals in the back.

Do you know the model numbers of your amplifiers? You can use one to drive the sub and one to drive all 4 speakers.

The Necvox LCD can be fit anywhere. You won't need to buy anything except some cables.

[Rajith]

sam,

JBL 6400 and sound stream lil wonder 11.

Boston is not performing better with Amps even though its 240 watts, yes bolero can have only 4inch at front OE fittment area.

Do i need to bridge rear of both amp and to give each coil of sub or any single 4 channel front and rear bridged can pump in the sub ?

In short i will have 2 channels of one sub unused even after connecting to rear pioneer blue cones , Am im right, shall i proceed .

In need shrill yaar with bass

[Sam Kapasi]

Originally Posted by Rajith

sam,

JBL 6400 and sound stream lil wonder 11.

Boston is not performing better with Amps even though its 240 watts, yes bolero can have only 4inch at front OE fittment area.

Do i need to bridge rear of both amp and to give each coil of sub or any single 4 channel front and rear bridged can pump in the sub ?

In short i will have 2 channels of one sub unused even after connecting to rear pioneer blue cones , Am im right, shall i proceed .

In need shrill yaar with bass

No, thou shalt not waste any channel Mr. Shrill.

Take one amplifier (ensure that it has LPF for both front and rear channel) - put the lpf on for both front and rear (as a reference keep it at 100Hz) and keep the gains identical.

Bridge the front to put into one coil and bridge the rear to the other coil. ENSURE that you have your polarities right. No + and - mistakes.

Now take the other 4 channel and put the HPF on on both channels. For the boston front put the HPF at about 200Hz. For the pioneer blue ovals out the HPF at 100 HZ (keep it the same frequency as what you ahve kept for the LPF on the woofer. Example if you keep the woofer LPF at 120Hz, then keep the oval HPF at 120Hz too)

These are the basics of the system. I suppose your installer will do the rest.

[Rajith]

boss,
how to confirm check HZ in the amp and make sure that all identical for 100 and a20 cases.All i see is screws with doe marks???

in continuation to above querry

If i am changing my DVC pioneer sub to JBL S12 or AD C124SVC and installing only one 4 channel AMP of JBL.

1)Then should i put amp rear in LPF mode for sub and front HPF mode for oval?.

2) Should still maintain same frequency as what i have kept for the LPF on the woofer. Example if i keep the woofer LPF at 120Hz, then need to keep the oval HPF at 120Hz too ?

[abhipuru16]

Guys!
I just completed with tuning my amplifier with a Digital Multi-Meter.
Everything, I think, went good "finally". I am writing a long post describing all that happened today.
The outcome is many times better as before the vocals were not being played to my liking.

First of all, the equipment-

Velocity VPA4130 Amplifier
Fiesta Stock Headunit with Pre-outs taken from the Mainboard

According to the amplifier's rating of
4X130Watts RMS at 4Ohm
2X400Watts RMS at 4Ohm

I was aiming for 23V for front channel and 40V for the rear channel.

So, I first stickered and labelled all the speaker wires to keep polarity under check.
I put the Multi-meter's + in the place where my sub's positive went and "-" likewise. The subwoofer runs bridged from the rear channels.
After that, I set the 50Hz 0db test tone on repeat and kept the volume to 75% of my headunit's maximum volume which is 34, that is, it was set at 24.
Now, while increasing the gains, their came a point where there was kind of a hilltop, after which, a further increase in the gains resulted in a decline in the voltage that the DMM showed.
When the volume was at 24 the hilltop came in at 20.xxV. Further increasing the gains resulted in a decrease in the voltage.
So, after a lot of tinkering around I frustratingly maxed the headunit's volume at 34 and then tried setting the gains. This time the maximum voltage I could achieve was 38.9V.
Now, during all this, the interesting thing I noticed was the gains were set quite low for both front and rear channel. Almost like 1/5th or 1/6th of the total.
The best part was that the gains for the front channel were set when the DMM read exactly 23V.
I am thinking, could I have further gained those 2V in the rear channels if I had set the volume to something like 30 or 32?

By the way, before proceeding with setting the gains, everything was set to a big "ZERO" both on the headunit and amp.

Is there anything wrong?

EDIT-
Also, given that I have taken pre-outs from the Head-unit's mainboard, even if I turn the volume to maximum and set the gains, would there be any distortion that could cause problems in tuning?
I don't think so because we are taking the signals well before they are fed to the Head-unit's amplifier.
Correct me if I am wrong.

[Sam Kapasi]

Originally Posted by Rajith

If i am changing my DVC pioneer sub to JBL S12 or AD C124SVC and installing only one 4 channel AMP of JBL.

1)Then should i put amp rear in LPF mode for sub and front HPF mode for oval?.

2) Should still maintain same frequency as what i have kept for the LPF on the woofer. Example if i keep the woofer LPF at 120Hz, then need to keep the oval HPF at 120Hz too ?

Yes. But what about amplifying the front end?

Yes if you keep the woofer lpf at 120, you should keep the oval hpf at 120 too.

[abhipuru16]

What I want to know is, did I cross the hilltop when I frustratingly turned the volume on the headunit to max?
Did I miss the sweet spot?

[low_bass_makker]

Do this with the speaker disconnected !!!

[navin]

Originally Posted by Sam Kapasi

Yes if you keep the woofer lpf at 120, you should keep the oval hpf at 120 too.

I prefer a little overlap between the front midwoofer and subwoofer. this compensates for road noise which is in the region of 60-100Hz and by crossing the front midwoofer as low as possible (without stressing it) one retains some semblance of a front soundstage.

[Sam Kapasi]

Originally Posted by navin

I prefer a little overlap between the front midwoofer and subwoofer. this compensates for road noise which is in the region of 60-100Hz and by crossing the front midwoofer as low as possible (without stressing it) one retains some semblance of a front soundstage.

His ovals are in the back. Many people prefer a slight overlap but:

His front is a coax 4" and he plans to leave it unamplified. If hje overlaps the frequencies with the rear ovals and subwoofer he will get a hump for sure.

He might enjoy the hump, the lord knows I do.

[abhipuru16]

Originally Posted by abhipuru16

Guys!
I just completed with tuning my amplifier with a Digital Multi-Meter.
Everything, I think, went good "finally". I am writing a long post describing all that happened today.
The outcome is many times better as before the vocals were not being played to my liking.

First of all, the equipment-

Velocity VPA4130 Amplifier
Fiesta Stock Headunit with Pre-outs taken from the Mainboard

According to the amplifier's rating of
4X130Watts RMS at 4Ohm
2X400Watts RMS at 4Ohm

I was aiming for 23V for front channel and 40V for the rear channel.

So, I first stickered and labelled all the speaker wires to keep polarity under check.
I put the Multi-meter's + in the place where my sub's positive went and "-" likewise. The subwoofer runs bridged from the rear channels.
After that, I set the 50Hz 0db test tone on repeat and kept the volume to 75% of my headunit's maximum volume which is 34, that is, it was set at 24.
Now, while increasing the gains, their came a point where there was kind of a hilltop, after which, a further increase in the gains resulted in a decline in the voltage that the DMM showed.
When the volume was at 24 the hilltop came in at 20.xxV. Further increasing the gains resulted in a decrease in the voltage.
So, after a lot of tinkering around I frustratingly maxed the headunit's volume at 34 and then tried setting the gains. This time the maximum voltage I could achieve was 38.9V.
Now, during all this, the interesting thing I noticed was the gains were set quite low for both front and rear channel. Almost like 1/5th or 1/6th of the total.
The best part was that the gains for the front channel were set when the DMM read exactly 23V.
I am thinking, could I have further gained those 2V in the rear channels if I had set the volume to something like 30 or 32?

By the way, before proceeding with setting the gains, everything was set to a big "ZERO" both on the headunit and amp.

Is there anything wrong?

EDIT-
Also, given that I have taken pre-outs from the Head-unit's mainboard, even if I turn the volume to maximum and set the gains, would there be any distortion that could cause problems in tuning?
I don't think so because we are taking the signals well before they are fed to the Head-unit's amplifier.
Correct me if I am wrong.

The speakers were disconnected, don't worry.

[navin]

Originally Posted by Sam Kapasi

His front is a coax 4" and he plans to leave it unamplified. If hje overlaps the frequencies with the rear ovals and subwoofer he will get.

if his front coax are unamplified he'll barely hear them unless he fades the rear and subs down. also he should put a small 1st order passive filter to those 4" coax to prevent bass over load to them.