A couple of months ago I ended up purchasing a completely new sound system for my car.

I ended up deciding on:

Front Stage - Focal PolyGlass V1 6.5" splits

Rear Stage - Focal PolyGlass V1 689 Coaxils

Speaker amp - Eclipse EA4000

Sub - Eclipse SW6200 12"

Sub Amp - Eclipse XA1000

Source - JVC KD-AVX11

Well I have my install was finally completed and all the components now sit snuggly in my car.

It is all very nice - but definatly requires some major tweaking. I know it has much more potenial

I can blatenly say that the tweeters are veeery harsh, not saying that they are bad speakers - just incredibly harsh. And after 10 mins my ears are bleeding - then after 10 mins of my ears bleeding the music must go down It is alll going great - that is, until the snare drum hits. However, there is already a thread about trying to get rid of the harshness, so I will not ask for help ith this, simply merely agreeing.

I am considering purchasing new tweets, simply because - well I can - and I don't so much like the surrent ones. Would this be applicable - or would i be better off buying new speakers all togther?

I am currently running the system Passive - and plan to go active soon enough, hoping that this will provide a nice improvement to the overall system.

Atm, (simply because my RCA limits it) the system is running in Mono - and one day I plan to change this to sterio, but I thought (perhaphs not) that I read somewhere that it is better - SQ wise anyway to run in Monophonic over stereio. I (think) i don't have imaging because of this.

I also seem to have major issues with stage width - I was wondering if I should/could purchase a TA for the system to help increase witdh and help the system to blend better overall.

Also, i know that I should sell the rears - they are faded out as much as possible (which is not much because my gains are set quite low anyway, and again because I run the system in mono - fading it on the Headdeck just goes side to side instead of front to back)

Bascially - my system is ok, goes loud and all that. But none of that really concerns me as much as making the system sound incredible. I wish to jump in and feel sounds from all angles - but it feels very narrow atm and sound is coming from everywhere (well i did get my bass to appear infront of me )

And lastly, I have NO midbass. Seriously - none at all, not even while parked, I hope that when I sound deaden the doors and install the speakers better tat this will fix (some of) the problem.

What would you do in my shoes?

Thanks in advance guys,

Ace

Focals are generally harsh so no suprise there.
How many preouts does the head unit have?
If it sounds like the sound is coming from everywhere and you have no midbass i would say that the wiring to the woofers have gone funky somewhere.

I bet if you played the tweeters by themselfs they would'nt be offencive to your ears.
This post neeeds to go into begineers forum with all the other harsh ideas.........cors

zion :



Get it set up properly first before you worry about width etc - why are you running mono ?

Its no wonder its not sounding right.

Because Mono is superior??

8 Pre outs, I guess that perhaphs it is possible that the positive and negative wires have been crossed over somewhere, maybe



Well i certainly dont plan to keep it mono I will go buy new RCA's on the weekend and wire it up in stereo.


I swear I did read that somwhere on here - although I may have misinterpreted the post.

Is Mono superior?

thematt, How is mono superior? I'm not having a stab, I'm genuinely interested.....

Wonder if I should wade in here?
Why is mono superior?
All natural sounds (IE anything not recorded in stereo) is monophonic.

Yep
Electric guitar is mono,
Vocals are mono
My voice is mono (tone?)

In-fact just about ALL recordings are mono. The only genuine stereo recordings are classical.
Go to a live concert
Its in mono (or panned mono)
The only place stereo exists is in classical recordings.
So are most recordings mono then?
Nope they are ARTIFICIALLY generated stereo.
Does that make em crap..

KISS brigade
Beat a mono setup. Yep you cant.

The ultimate test of a stereo? To form a MONO centre using a pair of speakers.
Even then you have a TINY sweet spot where it is "right' (if your lucky)

Do you honestly believe a stereo setup would get anywhere near a mono setup for a single instrument or voice?

The ultimate duplicity? Trying to emulate a live mono concert with a stereo system.

Point
Stereo is not the best.
VBAP (vector based amplitude panning IE mono) would wipe the floor of any stereo system.
Now we have settled that, continue on.

*runs and gets popcorn*

That almost kinda makes sense if you were to pack the drums, guitar, singers etc all into the same spot so that everything was coming from a single source

but you don't.



Although if you were trying to reproduce a single instrument , and had no interest in accoustics etc and only had one ear I can see how it might be probably 'superior' .


Can we stay on topic now ?

Lol, I was only messing about there. Stabbing in the dark to get a rise. Kinda knew Abmolech was waiting in the wings to jump in another thread.

HAHAHAHAHAHA nice work

It took roughly 13 hours for your response, but I was waiting patiently

THAT predicable eh?







I presume you have never been to a live concert.. yep its mono.



If you ever use radio on your system...its mono.



But don't let the facts get in the way of a good story.



To setup stereo you require 60 degree axis for both speakers, equidistant, and at the appropriate height. (Stereo cannot correct for vertical cues)

If your image is in front of your speakers you have panned monophonic, if the image is wider than your speakers (depth and width) you have stereo.

I wonder how many people on this board actually have stereo in their cars?



I suggest the vast majority of people have panned monophonic. IE their image is not wider than their car, nor is it out on the end of their bonnet.



Point

If your going to give advice on stereo, at least have the decency to achieve it in your own car first.





If your going to use rear speakers consider using a delay of about 0.5 milliseconds on them.

Ok so Mono sounds more 'natural'.

But would it be more impressive? More visually (soundwise ) pleasing for daily use?

Still all very interesting information and my question was answered in a scientific manner (the best kind)

But would I benefit from running the system in mono? It certainly doesn't sound as nice as some systems I have heard where the sounds pan from side to side.



Hehe - me too. I was hoping to read a reply from abmolech. Love reading technical data and the like - and I hope he posts again too



Actually I stuck my head down to my speakers again - but this time I went for the passenger side speakers, instead of my usual drivers side - seems that there is something wrong with the drivers side speaker (prolly in the wiring somewhere) because the passenger side seems to go fairly hard

I shall check it out tomorrow and let you know how it goes.



All makes perfect sense - and hence why I would think that for car audio systems - Stereo would be better. Even if Mono is better for one instruments replecations - (To me) it doesn't better for the replecation of songs?

Or is it simply that I have not heard a system running in mono - running at full potenital and/or sounding impressive.

Vividly awaiting correction


EDIT: I So do not take that long to post!

I know that the point of SQ is to get the sound build to sound like a live concert.

But since when does a live concert have 'superior' sound abilitys.

To me it has always just had superior atmosphere - while the SQ has been rather poor - loud but poor.

Perhaphs I just goto the wrong concerts


Sooooooooooooooooooo, if you DID achieve proper stereo - aswell as running in stereo - would this acheive anything interesting to note.

By which I mean - is it worth doing?



Cheers for that - do TA systems vary in price and quality - or is there not so many of them available. i would image they would be pricy

By live concerts, he's referring to the unamplified type. Not your rock concerts with lights and fireworks.

Left-right bias can and is achieved by panned monophonic.



So what can stereo offer that panned monophonic cant?



Depth.



The trick (illusion) with stereo is to get the image to go BEYOND the speakers.

An example might be headphones or ear buds, which may have a stereo signal, but the image is inside your head or at best on your nose.

Point

Headphones and ear buds are panned monophonic, IE the image does NOT go outside of the speakers.



I would wager, most people on this board have panned monophonic in their cars rather than stereo. Don't be so closed minded, most amplified sounds etc are monophonic, the ONLY time you will hear stereo is in a proper setup.



What is the primary recording difference between monophonic and stereo?

Stereo is recorded with coincident microphones 20 " apart (the distance from one ear to the other) Each microphone records a monophonic image, in a different place. IE the same sound, 180 degrees out of phase.

Monophonic is a single microphone (like just about every recording) placed near the sound to be recorded. Its weakness is it cannot tolerate reverberation.



So how do I go about achieving stereo in a car?

Excellent question, lets see if the "anti-mono" gentleman can actually describe what has to happen to make a stereo recording, into stereo listening.

Hint, "throwing" speakers equidistant only achieves panned monophonic, IE just like headphones.



Popcorn anyone?

Thats what I was thinking, live music with accoustic instruments

Just to add - Years ago I had the idea of buying a P.A. amp to use for all purposes and wanted stereo. I was shocked to learn from the guys in the shops that most live performances are in mono. They said stereo P.A. amps are few and far between and rather expensive

This is something I've been wondering about with those Chesky Records, reckon they use one mic. So how do they get stereo?

EDIT: Taking into account all the other things they don't do the same as everyone else, which I imagine would include panning. I don't have a Chesky CD so I must have read this stuff off someone elses and can't remember everything it said

Welcome to the real world. mono is best.





Now this is where it gets interesting. (Titled, How to destroy any hope of stereo)



The difference between panned monophonic recording and a stereo, is the amount of crosstalk (separation) In a stereo recording the crosstalk is around 60 % (70 % and your into panned monophonic territory) which means 60 % percent of the information is the same on the other speaker. Therefore we can mix the monophonic recordings accordingly, however all we have achieved is a left-right bias the next 'trick" is to add reverberation. With this we can position the instruments, left or right, forward or back at will. Problem is the recording engineer (oxymoron) is responsible for this. These talentless hacks like to show their ineptitude, by placing various instruments, and moving them around. Lord help us if they ever get hold of surround sound,

Oh wait they have.

To the original poster - MastaAce.

I was in your shoes a year ago when I installed a system in my suv - I had:
HU: Pioneer DEH-P7700MP
Seps: Focal Polyglass 165V2
amp: RF Punch P4004
Sub: 10" JL Audio 10W3V3

I had the seps in the kickpanels (3/4" MDF flat panel) and built a sub box/amp rack combo in the rear.
Immediately, I noticed a "rainbow effect" with my imaging - thus I transferred the tweets on top of the dash.
Soundstage went up and I played around in positioning the tweets to get better imaging. Yup, them Focal tweets were bright.

For months, I had this set-up and from time to time tweaked the HU.....but for some reason, I just wasnt that satisfied.....its like there was something missing. Thoughts of changing amp, seps and Hu came into mind, but i said I'd live it at that till I could save up again.

When my car club suggested that I join our upcoming car show, I revamped the woodworks of my sub box/amp rack combo.......I made it a lot smaller. Re arranged all wirings & made fiberglass kick panel enclosures for my seps. While in the process, I also dropped the tweets to -3db on their passives.
Once done, we finally connected the HU to test everything out......

......when we fired up a CD and listened to the first few seconds of the track, both my installer friend & I looked at each other in amazement at how everything sounded - it was magnificent! We didnt even touch anything on the HU & kept it all flat/0. My sounds feels like it is now in 3d compared to the previous one which was like just 2d. I'm a happy camper!

Install is the key!

I'm sure we sometimes feel that there might be one component in the chain that wasnt performing as we expected it to, but do exhaust all possibilities and scenarios to make it work right. If after you tried your best & it still doesnt perform - then feel free to change it. But there are also times when a component jumps up on the 2nd try & surprises us!

Good luck in your install!

Ah, Check Interestingly enough I am not a fan of rock music


Ok so Monophonic provides a better replecation of sound.

Therefore In terms of SQ Mono > Stereo.

However, consider this situation:
(Not nessecarily my view, but just for interests sake)

Say I like depth. And enjoy creating 'illusions' with my speakers.

Would I be sacraficing much SQ? If I prefer the depth over a slight loss of SQ.

Also, can you create width with monophonic?


Please.


Ah ok, so you also have more control over direction and placement with monophonic?

So how does one go about 'placing' instruments. (which may require you to explain reverbation and how to achieve 'Left' 'right' bias)



Cheers bud. Sounds like I have got something to work towards. Installation and fiddling around with speakers is half the fun anyway I think my sub box is too small atm though.
---------------------------------------------------------------------------------------------------------------------------------------------

Well I pulled the door skin off today. The drivers side door woofer seems to be working at about 90%

This would leave me to believe that the positive terminal is on the negative terminal and vise versa. However, since they wouldn't fit like that, something else must be wrong. Exact wiring worked perfectly with my last pair of speakers

Any ideas? Had quite a think about this.

It's hard enough getting stereo right, let alone heading down the path to obscure, untested (at least in any serious SQ comp car anywhere in the world) and not "in mainstream production" setups like mono.
Im sure its great and facinating, but try to get stereo right first! thats a big enough challenge in itself.

Definately concentrate on install, it does make all the difference.
I run around $700.00 worth of gear in my car and still manage to do ok in SQ comps, which probably has something to do with the 1k plus, DIY install I have.
You can make even basic old school gear sound fantastic with some serious time and energy on tune and install.

IMO you should be doing it the other way around.

Get Mono right first, then move onto Stereo.

If you cant get one channel of sound right, how can you expect to get two?

How do you know when you have 1 channel of sound right?

Certainly not from imaging cues, depth, height or width.

Possibly accuracy and linearity, but without a stage how can it sound right?

Bugger it, its a strange argument and Im too focused on getting stereo right to even be thinking about mono... sigh..

Mono has PERFECT imaging cues. It is far better then stereo could ever be on Imaging. You have Mono right when you have height and image right where it needs to be. Width is a Stereo thing when it leaves the car boundaries. Depth is a stereo thing when it leaves your windscreen. Until then, they are both mono.

Dynamics, linearity, accuracy etc. can all be gotten easier with mono then with stereo. Its like a first step to the ultimate (Stereo ftw ).

ahhh.. I see what you are saying, only problem is I'm getting all interested in mono again, took me months to get it out of my head after the first time I posted up a thread regarding mono..

Are you talking mono as in zero crosstalk, or true mono with a single channel only and a single driver for each low mid and high?

firstly, before this thread degenerates (further) into a technical poo-slinging about the qualities and deficiencies of mono vs waveguides (did I read that right??), lets try and sort out the original poster's questions in the most simple way possible. THEN, gentlemen, you may resume your poo-slinging.

you need to test that your midbass woofers are in phase with each other and that they are correctly sealed to the door, so that no air is escaping from round the edges.

to test for phase; grab a AA battery and touch a wire briefly from the positive terminal of the battery to the + terminal of the speaker, and the neg to the neg. Does the speaker cone move in or out? Then do the same for your other speaker.
Both speakers should be moving in the same direction (ie out or in), what you dont want is to have one speaker moving in, and the other outwards. then wire them up accordingly at the crossover. This might already be correct, but it's worth checking.

Also, try changing the polarity of the speaker wire at the sub as well (where the wire meets the subbox, or at the amp if it runs direct). Have a listen to the difference - it might help alot, or only a little, or not at all.

Try putting some closed cell foam (comes in a thin black adhesive backed strip, from bunnings) around the edges of the front speakers to make sure they are sealing to the doors correctly.

grab some more speaker wire and extend the wire from the tweeters to the crossover. then grab a packet of bluetac and stick a whole glob on the back of each tweeter. experiment with placing the tweeters in different positions around the dash and the doors and kickpanels. my focal V2 tweeters (TN46s) went from sounding detailed and harsh to just detailed when I moved them from the windscreen to the kicks, although I did lose some stage height. also, if you have the option, change the tweeter attenuation at the crossover to its lowest setting, see if that helps.

make sure all your EQ's and loud functions etc are turned off at the head unit. Also, try turning the gains for the front channels at the amplifier down
a fraction. this might help with the harshness at loud volumes.

Once you've done all that, THEN ask abmo and ~thematt~ how to go about making it sound, as you say, "incredible". Cause I dont quite know how to do that bit yet....

(ps guys if any of this sounds wrong PLEASE correct me)

cheers mate

Matt

oh yeah.....

one thing that did stick with me...

I went and saw Travis at Stylyn the other day. Bloody helpful bloke he was as well.

he did say that lots of people on this forum like to say that focals sound harsh. He believes this is, and I quote, poo.

he runs focals, loves them (slightly higher series though) and plenty of others do too. Get the fundamentals right, then start spending on equipment.

(now if only I could follow that reasoning, I would be rich I tells you. RICH!)

You wanted to be corrected?
While 180 degrees out of phase is a problem (probably the main one) a close second is a baffle. (yep wave guides again )

If you consider a driver transfers mechanical energy into acoustic energy (vibrates the air) and the propagates into a sphere, if unimpeded. Therefore the larger the air it expands into, the less energy reaches you.For example distance. While distance maybe unavoidable, the air volume that it expands into is not. IF we were to cut the sphere in half with a suitable baffle (This is the correct term of infinite baffle, IE a baffle that is large enough that the frequencies expected cannot get "past" it. Effectively the baffle might as well be "infinite")



Therefore the driver radiates into half a sphere rather than a sphere (Technical term steradians, IE 2 steradians = half a sphere. Steradians means "solid" same word for "stereo")then more vibration reaches you, actually twice as loud, 12 dB.



Point

Your mid bass would be over twice as loud if you made a baffle in the door large enough for the waves not to get around . (Hint sealing up the basket mount isn't going to "cut it") 250 Hz is approx 4 feet long, so my suggestion is you start with a "infinite baffle" IE mount the driver in a sealed enclosure.(Preferably of the correct volume)


No it wasn't, but since you meantioned wave guides, I took the liberty of using them as well.
It is not a degeneration, that happens when people start talking about cable and amplifier sonics..

Pop corns getting low,



Where are the anti mono boys?

thanks abmo, that was pretty much the sort of correction I was looking for

PS just taking the piss about waveguides...

Thanks bud,

Already done the battery test - and sealed the speaker etc - it is definatly something with the wiring somewhere. A weekend job

Interestingly enough, the system does sound 'incredible' with things like female vocals - strings and just generally things I wouldn't normally listen to. Just doesn't like snare drums. Which are in most songs I listen too. Feels strange playing Mariah Carey in my car I wanna go back to playing NWA.




I was told by some fool - that " sealed box wreck speakers" and "subs were designed for boxs, not speakers"

Getting a box of correct volume in the door would be a mission though

Question
Would you be getting more midbass from a speaker sealed in a box than an array (Of speakers) simply sealed around the mount?

My orignal question still stands though, anyone?

Depends.

Assuming they are all the same drivers, and power amplifier can "meet" the task.

A sealed enclosure is a genuine infinite baffle (IE it has no end), what most people take infinite baffle as, is the enclosure volume has no effect on the "Q" of the driver.

(It is not true, however as long as everyone is on the same page, it doesn't matter)

The back wave cannot interfere with the front wave, so a gain of 6 dB is to be had over a non delayed baffle.

Each driver equates to an increase of 3 dB with the doubling of surface area. IE 2, 4, 8,16 . So 4 drivers in an array would give us an extra 6 dB. Or we could be radical and build a proper enclosure (IE the baffle is a blocker, not some sheet metal with sound deadener on it)

So potenially, say the speaker was installed in a sealed enclose with everything 100% correct it would be eqivilent of 4 speakers installed in an array, simply sealed around the MDF?

And the box would have to be made out of MDF of course.

Cool, I have more questions - but it is lat eand they shall wait.

In the mean time. . . . reverbartion is what?

Reverberation is the direct versus the indirect.
If it is within 30 mls it adds "colour" (diffusion)
Between 30 -60 mls is what most people refer to as reverberation (IE what give us the perception of space and depth)
Over 70 mls is an echo (Hence a room without echos is anechoic)
IE if there is no secondary reflection (Indirect), then we are only listening to direct sound. Just about everything has at least a secondary and more likely third etc.

An example might be a guitar baffle as secondary colouring, the floor roof and walls as second reflection (reverberation). One of the better principles to come out in semi-recent time is "surround sound". This emulates the secondary wall reflections of a room, and therefore can give a much superior sound system over stereo. (The reason why you can't buy just two speakers anymore. (unless you travel off the beaten track). If you think about it, a refection (indirect) could simply be replaced with an attenuated speaker, and therefore give a much better reverberation.

The only place the out-dated stereo survives is in car audio. Ironically it is the one that could most benefit from a surround sound upgrade.
Now where are the stereo fanatics?
Popcorns just about run out.

Seems like they are very quick to criticise something they have not a clue about.


You will gain up to 6 dB if you have a suitable flat baffle versus no baffle. 12dB if your flat baffle is a flat wave guide.(Much more if you use a concave wave guide)

Concave wave guide?

Think its time for a search

Just a point to note though.
-------------------------------
My midbass 'appears' as if it is coming from the windscreen - or even the dash mounted tweets.

I though that midbass was directional?

Its got me.

Even sub bass can be locatable under the right set of circumstances. (IE you can hear the general direction of race cars at considerable distance)

Let me preempt this by mentioning bone conjunctive auditory perception. This is where you get a sense of direction, from the fact the sound has a more direct path, IE it vibrating your bones, and into your inner ear. It can happen in a car, through your feet, or your hands on the steering wheel.
Point
You may believe you are hearing the location, but in fact you are feeling it.

On a purely air related auditory experience, we use two primary methods for location.Time difference arrival, and intensity difference.
What are our limitations?

Intensity, we cannot locate below about 800 Hz and normally above 20 KHz.

Time we can locate at 50 Hz to 2500 Hz. (we don't have the processing speed to go higher IE it is the brain that "hears" not our ears, IE one brain therefore monophonic is best )

It is not as simple as the frequency ranges, as the vary from person to person, but more importantly the direction in relation to our head. (We don't have ears that can turn like animals can, IE dogs etc) We can locate a 500 Hz wave directly in front to one degree (better get those speakers in the right place!), however perpendicular, we would struggle to locate it at all. (the reason why we turn our heads) Conversely, intensity based hearing is the opposite. A 5 kHz wave is almost impossible to locate directly in front (The reason why ambient tweeters work so well on the interior mirror)

although we do start to get vertical cues at this range, which we suck at locating. However place this tweeter perpendicular to our head vision, and we can locate that tweeter with minute procession. (Within fractions of a degree)



Popcorn has run out.



Do I therefore assume stereo sucks and monophonic wins?

???