[navin]

Originally Posted by viXit

Because low frequency sound from subwoofers is the least directional, is it not almost the same with a single subwoofer?

I’m mainly asking to know what the advantages of using stereo subs are.
Do you use the stereo 12”s to their potential?

but what drove the decision to bridge the rear 6x9es too?
Does the Camry not have tweeter mounts for the rear?

Is 200hz the least frequency that the HAT full ranges can handle or are you saying that you have set your HPF at 200hz?

You mentioned earlier on that you’re mostly chauffeured around and you’re in the back seat mainly, how do you control the music?

Bass is difficult but not impossible to located. That said a single subwoofer would have more than done the job for me. I had a very different purpose for using 2 subwoofers - low frequency distortion.

As a voice coil moves within the magnetic field the effect of magnetic field on the voice coil changes. This is because when the voice coil is moving a lot part of the voice coil is outside the magnetic field. This sometimes leads to non-linear movement of the voice coil.

By using 2 subwoofers I need have to linear motion in the voice coil to achieve the same sound pressure level at any given frequency. Which means the movement of the voice coil will be more linear.

I bridged the Alpine because I had the available channels to do so. If I had a 2 channel amp instead of a 4 channel amp, I would have used 2 channels. The Alpine was from a prior install and I did not want to buy a new amp for rear fill.

The Camry has no speaker pods in the rear doors. Only holes for 6x9s in the rear deck. To prevent the rear speakers from getting "modulated" by the subwoofer, I covered the rear basket/magnet of the 6x9 in foam and covered the foam with black cloth (similar to what is used for home audio speaker grill material). The black cloth camouflages the foam and ensures that one cannot easily see the rear speakers even when the trunk is open.

Yes the HATs handle everything upwards of 200Hz and the 6" woofers handle everything below that. 2 channels of the Steg K4.01 drive the HATs and and the other 2 channels drive the Morel 6" woofers.

[viXit]

Originally Posted by navin

By using 2 subwoofers I need have to linear motion in the voice coil to achieve the same sound pressure level at any given frequency. Which means the movement of the voice coil will be more linear.

Can you elaborate on this a little more. I thought the surround of the subwoofer is supposed to make sure it moves linearly in the magnetic field.
I don't understand how adding another one helps.

I bridged the Alpine because I had the available channels to do so. If I had a 2 channel amp instead of a 4 channel amp, I would have used 2 channels.

The Camry has no speaker pods in the rear doors. Only holes for 6x9s in the rear deck.

Since bridging them increases the power supplied to the speakers, would they not become louder?
And is there a limit as to how many watts we can be sending through a speaker?

To prevent the rear speakers from getting "modulated" by the subwoofer, I covered the rear basket/magnet of the 6x9 in foam and covered the foam with black cloth

Could you share some pictures of this please?

Does it improve the SQ to such an extent that you can feel it or is it done for peace of mind?

[navin]

Originally Posted by viXit

Can you elaborate on this a little more.

And is there a limit as to how many watts we can be sending through a speaker ?

Could you share some pictures of this please.

The spider is largely responsible for keeping the coil linear in a voice coil gap. The compliance of most surrounds is too soft to help much. The old accordion type cloth surrounds were more effective in this.

That said, see the image below. As the voice coil moves part of it leaves the magnetic field (top plate). Hence the magnetic field is only on part of the voice coil and there is some loss of linearity. By limiting the movement of the voice coil, we can ensure better linearity.

Most transducers will reach their physical limits long before their thermal limits. Tweeters are particularly susceptible, but woofers are too. The difference being you may woofer complain (distortion) before it blows; a tweeter will not give you any such warning.

Due to Covid-19 I don't go out much. Once this pandemic is past, I will post pictures.

[viXit]

Originally Posted by navin

That said, see the image below. As the voice coil moves part of it leaves the magnetic field (top plate). Hence the magnetic field is only on part of the voice coil and there is some loss of linearity. By limiting the movement of the voice coil, we can ensure better linearity

Navinji,
By limiting the amplitude of the voice coil, you're keeping it within the magnetic field.
But to compensate for the reduced volume you have added a second subwoofer?

Am I understanding it correctly?

That is a lot of thought going into a setup.
It must sound really marvellous.


Was the low frequency distortion so noticable that you ever had a problem in your earlier setups?
Or did you always have two subs?

[navin]

Originally Posted by viXit

Was the low frequency distortion so noticeable that you ever had a problem in your earlier setups?
Or did you always have two subs?

Some people have ears that are alert to low frequency distortion. I am one who is cursed with such ears. Maybe it is because of all the Pro Audio equipment I used to play with in my teens and twenties. I used to "mic" drums and percussion instruments and helped run my college radio station so had to work with every band that came through the college. I even had the opportunity to visit Record Plant and Sterling Sound (both defunct today).

I have always had 2 subwoofers. Ok let me correct that statement.

The first car system (1989) I built in India had 3 10" subwoofers in a transmission line in a Contessa 1.8. I built these subwoofers myself. Not just the box, the woofers themselves. Back then I even built my own 4 channel 35W rms car audio amplifier.

My second (1995) had 2 aperodic 12" Infinity woofers in a Opel Astra. My third (2004) had a single sub using 2 12" Illusion Audio woofers in push-pull (Isobaric) in a Octavia vRS. The Camry is my 4th car.

[viXit]

Originally Posted by navin

We removed all the processing in the OEM HU using an Audision Bit 10D, added better fullrange speakers in the dash, upgraded the front midwoofer and rear speakers and added some nice amplifiers and subwoofers and we still have not found what we are looking for.

Sir,
How did you remove the Processing using the DSP?

You mentioned that the rear speakers only get 300hz and up, how did you send the sub 300hz signals to the rear?

Did you take it from the front?
Do the Fader controls work from the OEM-HU?

[navin]

Originally Posted by viXit

Sir,
How did you remove the Processing using the DSP?

You mentioned that the rear speakers only get 300hz and up, how did you send the sub 300hz signals to the rear? Did you take it from the front?
Do the Fader controls work from the OEM-HU?

My Audison Bit One can re-DSP the speakers to sound flat. However I don't like a flat sound so I tricked my Audison. I set the treble 2db high. Then ran Audison. Audison hence tried to flatten the sound and compensated. Now I have my treble at 0db and just the right amount of roll off.

The Front channels are biamped. Hence above 300Hz has it's own amp and below 300 Hz has its own amp channels.

Yes sir, both my fader and balance controls on my OEM HU work as they should. I also have fader and balance controls on the Audison but never use them.