[CrackedHead]

Originally Posted by frankmehta

Music is still not as rocking as I thought. But RTA and some tweaking will do the trick. Cabin gain is turning out to be a large factor in the boot, and needs to be worked out soon. BUT, I know it's going to sound amazing in a few days!

Gee! Do I foresee the Eclipse deadhead being traded for a Pioneer Premier with its auto TA and EQ capabilities ?

[frankmehta]

Originally Posted by wildchild4lyfe

in the end is all about the music...i agree...
i just think you should clip the amps on the left side..i would give it a more balanced look.

We shall think about this during the next upgrade

Originally Posted by naughty001

1) You have a sedan this is always going to be softer than a hatchback because a well built sedan tries to keep that sound in the boot instead of allowing it to spread. In theory according to my way of thinking it should be easily around 6 to 10 db lower in sound pressure level than having the same equipment in a hatchback vehicle

true that.

2) Secondly you have a box in your boot/trunk, so its a box within a box with a hole on one side which is supposed to let the sound go out into your cabin. does this sound familiar .... it should since that type of arrangement is more commonly known as a bandpass because its a box within a box with a port (the hole is effectively a port with a small surface area) creates the bandpass enclosure. So this on its own will be creating cancellations that you dont know about

i no longer have a 'port' on the shelf.
but i do believe the cancellations are the cause of the problem

3) thirdly in installing 6x9 speakers on the rear deck which have the rear exposed to the output of the sub this creates further cancellation because the sub will be creating pressure and hence this pressure will be attempting to move the cone, Every panel that is subject to that pressure will resonate and anything movable will move in conjunction with that pressure even if it already has its own natural movement already so effectively the 6x9 will be attempting to work like a passive radiator but if the musical signal it receives is out of phase with the sound that the sub is creating you will get further cancellation, hence why installers avoid to use any speaker on the rear deck if you dont have those enclosed

To be honest i would have used another smaller set of efficient coaxials on the rear doors rather instead of 6x9's because eventually the output/pressure from the sub will cause the output from the 6x9's to distort as well as cancel other sounds that you should be hearing because the front wave of the sub and the rear wave of the 6x9 would be creating a destructive interference and also the as i have stated above the pressure and resonance cause the 6x9 to work like a (poor) passive radiator.

Anyway it's all just theory on my part and just my opinions on what could possibly be causing your unhappiness because you don't seem 100% satisfied. Maybe it is tuning or maybe its a few install concept flaws (note : i dont mean installation but the underlying concept), but if the tuning doesn't work as you like it then possibly whatever i have said might be factor's to consider

i dont have slots on the rear doors, or would have used them first.
the sub-bass hasnt changed after adding these co axials

Originally Posted by mmmjgm

Hey Frankie,

Where did you buy the morels from ? Which shop ? Where ?

Cheers
M

preeti trading corporation. *PTC*

Originally Posted by CrackedHead

Gee! Do I foresee the Eclipse deadhead being traded for a Pioneer Premier with its auto TA and EQ capabilities ?

I dont know about the Auto TA abilities of others, but the TA of Eclipse, alongwith the imaging and the sound quality is so ASTOUNDING, that I wouldnt dare to dream of a new one until this one broke

i no longer have a 'port' on the shelf.
but i do believe the cancellations are the cause of the problem

so one quick question if you dont mind, how is the bass then entering the cabin, it needs some method of passing from the boot/trunk to the cabin of the vehicle. If you dont have access holes this will further reduce the sub bass in the cabin, so i will appreciate some clarification on how this is achieved

[frankmehta]

According to most, having a 'vent' to let the bass into the cabin is not compulsory. I believe there should be a vent, but there is no facility for one after the rears have been installed. I don't intend to cut the shelf or the metal underneath, hence will have to do without it.

[Gilead]

How do you know the current set up is not sounding as good as it can? You must have some reference I assume. I am sure it's sounding better than the earlier Esteem set up. Have you auditioned another car with a similar set up which sounded better? Or is it good 'ol intuition and a good pair of ears.

[frankmehta]

The Esteem was tonally very different, and I like the Fiesta much more, save for the way the sub-bass is playing upfront. Needs tuning, that's all!

[shajufx]

Originally Posted by naughty001

how is the bass then entering the cabin, it needs some method of passing from the boot/trunk to the cabin of the vehicle. If you dont have access holes this will further reduce the sub bass in the cabin, so i will appreciate some clarification on how this is achieved

Naughty, I felt you just spoke what was going on in my mind through your previous elaborate post. I always felt there should be some opening or a hole from the boot to the cabin for the 'air-power' from the sub to travel freely. The subwoofer vibration hitting the rear speaker cone sounds very much practical as this is the only delicate area in the whole boot.

I am not a technical guy, but thats a very basic thought anyone would have. According to me, its as equal as setting up a 5.1 home theatre speakers in a living room, except the sub-woofer wired and seperated in an adjacent room thats is tightly closed. Do I sound technically wrong ? Open to corrections.

In my case, I have left the rear speaker vents open by removing the stock. Subwoofer effect was tested and sounded muffled before removing the rear speakers. Now the rear left and right vents act like a perfect port. So, its a clean and tight punch through my RF 12" sub.

Originally Posted by frankmehta

According to most, having a 'vent' to let the bass into the cabin is not compulsory. I believe there should be a vent, but there is no facility for one after the rears have been installed. I don't intend to cut the shelf or the metal underneath, hence will have to do without it.

I think testing the difference with and without the rear speakers (meaning the left and right vents in open and close position) will be the best judgement ignoring all the theory for the time-being.

[Gilead]

I recently sat in a car which had a sub in the boot. But the bass from the sub seemed to be emanating from the dash! It was unreal and awesome sounding. How is that effect achieved?

[Mi10]

Originally Posted by Gilead

I recently sat in a car which had a sub in the boot. But the bass from the sub seemed to be emanating from the dash! It was unreal and awesome sounding. How is that effect achieved?

I guess, it is something to do with TA.

[shajufx]

You mean Travel Allowance ? Sorry for my ignorance !!

[Mi10]

Originally Posted by shajufx

You mean Travel Allowance ? Sorry for my ignorance !!

Its Time Alignment

P.S: Your ignorance really made me look like

[Gilead]

Originally Posted by Mi10

Its Time Alignment

P.S: Your ignorance really made me look like

Ok, I must be even more ignorant than Shaju. How does this TA make the sub sound as if it's playing in the dash?

Originally Posted by Mi10

I guess, it is something to do with TA.

Not necessarily only T/A. It would definitely be a lot to do with the arrival times of the various frequencies to your ear but phase, amplitude and crossover points (in terms of overlap or underlap) also play a huge role

its also a psycho acoustic effect - when you cannot see the subwoofer it is easier to imagine those frequencies as coming from the speakers you do see especially when the tuning is done well as to allow such integration to occur

How does this TA make the sub sound as if it's playing in the dash?

Its not only T/A. Its the basic fact that no matter where the speakers are situated if the sounds from them all arrive to your ears at the same time then it seems like they all came from the speaker that has most of the frequencies playing or whichever speaker is louder

eventually as you turn the bass levels up you will perceive that bass as coming from the back, likewise if its at a similar sound pressure level as the other frequencies it is easier to perceive it as being integral to the sound that is arriving from the front speakers

its all about your tuning and also how good your equipment is because its easier to create this "upfront bass" illusion with better quality speakers and a bit of tuning work which could or might not include time alignment adjustments and phase and polarity adjustments as well as volume level adjustments and frequency equalization to ensure that the conditions are correct for this illusion to come about

EDIT : sorry for posting two posts so close to each other, i should have edited my post above, can a moderator please merge the two posts. Thanks in advance

[shajufx]

Franky, we are all waiting to hear your next project of "Drilling an extra hole in the rear". Do let us know whats your thoughts on that ! You know very well, closing the existing rear hole one can not, sorry a car can not perform.

[frankmehta]

Heheh, Shaju, I would desist from making a hole in my beloved car. The bass in the cabin is JUST fine, and just needs some boost at certain frequencies. Tried some boost from the amp today and the results are absolutely outstanding!
Will post the findings here soon.