27 replies to this topic

[Winno]

But getting back to my second post above, it's my understanding that levels need to be set so that they all measure the same at the listening position.
Is this correct?

Ta

[Luke352]

Winno, on Nov 5 2009, 10:23 AM, said:

But getting back to my second post above, it's my understanding that levels need to be set so that they all measure the same at the listening position.
Is this correct?

Ta

That's how i've always done mine Winno.




I don't get two seat and never will, my couch sits 3 but I only set my system up for where I sit, so why should my car be different? Plus last years finals in the two seat class the top 3 cars weren't tuned for two seats, so if single seat cars with there average passenger seat tunes can still beat the two seat cars in the top class why do we still support a class where the cars set up for that class can't even win at finals? But hey we've been over this so many times it's rediculous, there will always be those who refuse to give up there two seat tuned cars, and then the other camp who just don't see the point and don't even bother.

[Winno]

In some ways it's actually a step backwards.
Given the limitations of making a good, and I really do mean good two seater set up, and what this means in terms of actually reducing driver seat image quality, in my opinion only, I reckon it should be dropped.

I've heard some one seat systems that have been jaw droppingly good but never a two seater. Surely that should be meritted in it's own right.

Anyway, this is another issue.

Thanks for the help so far guys.

[Matt VIP]

Maybe consider competing in an SQ division with 2 seat staging to be a bit like competing in SPL. Do you actually need anything more than 135db in your car? Would you ever hit over 125db on your home system? Doesn't make it any less worthwhile as a goal to strive for.

Do you know how to build a car that hits over 135db? Nope? Well, some people do, and when you experience it, its awesome. Much the same applies to 2 seat SQ...

The same applies to any psuedo sporting endeavour requiring skill, knowledge and passion. Do you need it? No. Is it awesome? Yes (to some people). Just because it's too hard for you to perfect doesnt mean it's any less worthy.



[sorry for the OT rant!]

Edited by Matt VIP, 05 November 2009 - 02:11 PM.

[Winno]

Yeah, it is hard to get right. I don't believe anyone in Australia has done it yet where it's as good as some of the better cars from driver's side only.

But I'm practical as well and simply don't see the need to build something that nobody who travels in my car regularly will come even close to appreciating. I'll just have to make the driver's side so good that even the average of scores will be good enough to win.

There's something to be said about getting a fright about something in your staging when you're driving because it's so solid.

Edited by Winno, 05 November 2009 - 08:46 PM.

[syd-monster]

Winno, on Nov 5 2009, 09:41 PM, said:

Yeah, it is hard to get right. I don't believe anyone in Australia has done it yet where it's as good as some of the better cars from driver's side only.

amitedly I haven't heard a perfect 2 seater in the MEA format, although some get very close.
But I can only share (as I have no proof); true 2-seat cars existed in years gonne by. it was harder then too with no T/A and digital x-over rare. But people went a lot further with their cars too. not trying to put down what some competitors in MEA have done, but in the past we werent affraid to cut cars if need be. A little bit like the lengths some tuners will go to these days to fit those intercoolers or roll cages etc...
I guess the laws have kinda changed too...
either way horses for courses...

[Shreknos]

good luck with this winno, quite a informative thread... from what iv read, they say that enclosure size either side, say for midranges, or midbass, should be precisely equally volumes, levels matched both sides equally, and frequecy responce matched from both sides(if two seater)...

also, cyberpunkys roller has awesome two seat staging, as did fudds old eunos.... almost perfect, sounded better from cyberpunkys passenger side as it did in my install at the time...

[muzzy66]

Winno, on Nov 5 2009, 07:55 AM, said:

I must admit that after sitting in alot of cars now here and overseas, I am yet to find a car that images as solidly from both seats as it does from the driver's seat.
There will always be a compromise to take some of the driver's side goodness and give it to the passenger as well.

Mine right now does, not in terms of centre image (that's impossible IMHO) but in terms of how solid, sharp and fixed the image is (as well as tonality) mine is equally as good from both sides.

In fact, that was one of the key goals i wanted to achieve with this system build - at the end of the day it's all about symmetry, and making everything identical on the left and right side of the car.

Driver angles:
Make sure all driver angles from both sides are identical from both sides of the car. If your driver angles are different on the passenger side compared to the driver side, then as a result of a speakers' off-axis response characteristics, the speaker with more angle is going to produce more output at at that upper frequency. The fact that your ears are reciving more output at that specific frequency range from one side of the car will lead to a 'shifting' of the stage towards that side of the car when something in that frequency range is played by the system.

For example, imagine you're sitting in the driver seat of a car, and yoiu have 6" midbass drivers in the factory locations. Being in the drivers seat, the drivers side woofer will be further off axis (about 60 deg) then the passenger side woofer (about 45 deg). Because the driver side woofer is further off axis, it will probably be about -2db at 2khz, while the passenger side woofer is still 0dB at 2khz. This means that every time there is a singer that hits a 2khz note, their voice will appear to shift strongly and suddenly towards the passenger side of the car.

The best way to avoid this is to make sure that both left and right speakers are at pretty much identical angles (+/- 5 deg) regardless of where you sit in the car. If this is not achievable, only other option is to cross the speaker over below the point where the shift is occuring - for example, cross below 2hz in the above example. This allows you to essentially 'force' off-axis response out of the equation, so that both drivers have the same FR characteristics despitite there differing angles.

Driver Placement:
Actual locations of drivers must be the same on both sides of the car - as close as possible to perfectly symmetrical. If the left speakers are in different positioned to the right speakers (relative to their side of the car) then they will throw off the sound and make a great 2 seat stage near impossible to achieve.

Time Alignment:
If your time alignment settings are set up specifically for the driver side, then your system will sound very well integrated from the driver side but will sound completely out of wack from the passenger side.

What you need to do here, is set up left and right time alignment individually, as if the left and right sides of the car are two different systems altogether. Get the left tweeter, mid and midbass aligned with the sub (as the one central driver), then move on to the right side and get the right tweeter, mid and midbass aligned with the sub - if the install is done correctly/symmetrically, then the left settings and right settings will be identical when you're done.

Do not try to align the left side with the right side - once again this will make the driver side sound better at a major expense to the passenger side.

These are just some of my tips with system design / tuning when trying to achieve a two-seat stage. Some people don't care for it, and are happy with a driver-focussed system and that's fine - everyone has their own idea of what they want from their system. Personally, I feel that if i'm investing so much time and money into a system then I'd like it to sound good from any possible position, rather then have it sound like gold from one seat, and arse from everywhere else.

Edited by muzzy66, 03 December 2009 - 10:45 AM.

[Matt VIP]

have a listen to Pulse-R's car next time you're in melbourne, muzzy...

[muzzy66]

Matt VIP, on Dec 3 2009, 11:55 AM, said:

have a listen to Pulse-R's car next time you're in melbourne, muzzy...

Oh there are many, many cars' I no doubt have to listen to - Pulse-R's is one of them

In fact, I have to hear your car again one day too now that you've made the changes - plus the last time I heard yours it was on 'SPL' setting

Edited by muzzy66, 03 December 2009 - 12:02 PM.

[Matt VIP]

I was referring to the fact that Pulse-r seems to have an image that sits in, oh, about the centre of the dash from both the driver's and passenger's seats. Is it perfect? No. Is it pretty dang good? hell yes.


Mine, on the other hand, has an image that sits somewhere near the centre of the dash on Tuesday mornings between 9-11am, and god knows where any other time. And thats for the driver's side.

Seems to be the same whether its in SQ or Sounds Almost Loud settings - but yeah, next year we'll have to catch up and share notes

[muzzy66]

Fo shizzle - i'm stick suck very solidly in the middle of deciding whether to go 3-way or 2-way. I've got my system configuration laid out for either scenario, just having trouble deciding which way to go. Can't wait to get into the spirit of competition again though - it's been sooo long since I've had a proper season of competition, and even longer since I've had a finished system lol

But anyhoo, back on topic!

Edited by muzzy66, 03 December 2009 - 01:20 PM.

[Pulse-R]

really, try to get each driver pretty flat in frequency response first - by install or EQ.

set the crossovers to a bit wider than you plan to use them

then set the levels to be the same, or sloping down 1dB per octave (seems to be preferable in a car) for each driver

then set the TA to the distances

tighten up the crossovers

adjust the polarity to eliminate nulls at crossover points

trim the TA to firm up the image.