I've done it! I have found our ideal soundstage for Lara!

[MisterTedster]

After weeks of researching and experimenting I have found the ideal sound stage for our laras. Now the end result may be quite simple, but the process to arrive there was not. Basically, you need an amp that can high pass all the way up to 5k Hz on 2 channels, and then bandpass on the other 2 channels. Just this alone took me awhile to find until I found an a/d/s/ P640.2 on craigslist for a steal.

I did this using the Sony XS-GTX1620s components and a pair of Polk Audio db1000. As you can see this is a budget set up, but sounds fantastic.

Anyway, here is how you set it up.

1) Throw away all the passive crossovers. The amp will be taking car of all the high and low pass frequencies. (As you can see we're going for an active set up). If you do not have an amp that has the capabilities that I stated, then you can always get an external active crossover. It's just cheaper if you can find an amp that can high pass and band pass.

2) Mount the sony component mids in stock location, use the polk db1000 tweeters for the stock tweeter location.

3) Here's the tricky (or really not so tricky) part, the sony tweeters (that came with the components) will be mounted right on the A-pillar just on top of the dash in the corner where the dash, A-pillar and windshield meet; You don't even need to use any of the brackets, although I did use an angle bracket that fits very nicely. The wire can be stuffed very nicely in the A-pillar. Just from the A-pillar and windshield "gripping" the speaker wire, I didn't even use any double sided foam tape or screws to attach the tweets, they sit there firmly just fine. Now wire the polk tweeters and the sony tweeters in parallel to the amplifier. Here's the trick, wire the sony tweeters out of phase with the polk audio tweeters. That is to say, reverse the polarity (I will explain why below).


Now you're wondering why I have everything set up this way. The tweeters are mounted pointed to each other whilst reflecting off the windshield to raise and expand the sound stage and to set it where it's supposed to be, in front of you, like in a classical concert.

Why did I wire the dash tweeters out of phase? You'll notice that the distance between you and the stock tweeter location is much closer than you and the dash tweeter. By wiring out of phase, we are compensating for the difference in the path length that the sound has to travel. Of course this can be avoided by using time alignment, etc. etc. but I'm on a budget, and this sounds very good already.

The accuracy of sound is maintained with the use of the polk tweeters in the stock tweeter locations.

To sum up, two pairs of tweeters, each side wired in parallel (amp will see 2 ohms if both the tweets are 4 ohms apiece), with the dash tweeter (located where the dash, A-pillar, and windshield meet) wired out of phase and pointed to each other, reflecting off the windshield.

This is the best way to achieve accuracy and proper sound stage. Trust me I've tried everything, and by everything, I mean everything.

You guys can sound demo my car if I happen to make it to the SoCal meet.

I will be adding a third set of tweets for more complete fill and soundstage and then figuring out very precise pointing to see if I can avoid the rainbow effect. As of now, time alignment may be the only way to avoid it.

Pics and a diagram to come later.

edit: Clarified some points that could have been misinterpreted now that I read it again.

[~SolaRaSpeed~]

this is interesting and an idea i've considered before in the solara. I think pictures are in order so we can see exactly where everything is placed. I'm still using the factory tweeter location as I think the ideal spots are on the sail panel or on the a pillar and haven't had the time to make a mount for either spot as of yet.

and way to go on the active setup.

[99BlackSandv6]

Interesting. Post PICS!

[MisterTedster]

Yeah, I've had the dash tweeters mounted on the sail panels for a long time, and I was quite satisfied with how it sounded. But for me, even using angle mounts for the tweets, the soundstage seem just a tad low, at around my shoulders or so. Not only this, but it was too easy for me to identify the source of the sound (where the tweets were located). With my new set-up, it raises the sound stage to just about my ears and you cannot identify the location of the tweets with your eyes closed.

[~SolaRaSpeed~]

Yeah I've been told the a pillars are the spot for the solara. Looks like I need to get off my lazy butt and move mine already so I can enjoy sonic bliss. That and get a rf 360.2 for active crossover.

[MisterTedster]

Im going to add a third set of tweeters back onto the sail panels. I think it'll give me a more complete sound image since the sound stage is almost too far now, lol.

[Eye8Pussies]

hmmm...that is a very interesting way of staging the tweeters...and it makes a lot of sense too.

good work

[MisterTedster]

^ You'd be suprised. Coincidentally, there are several IASCA SQ competition cars that set up their tweets this way. Although it has become somewhat rarer as IASCA weighs accuracy more heavily than soundstage in their scoring.

[~SolaRaSpeed~]

do you still have 2 channels left to up the wattage on the tweeters instead?

[MisterTedster]

^ The wattage of the tweeters isn't the issue. I actually had to lower the gains of the tweeters since they were overpowering the mids. The reason for the extra set of tweets is only for fill and staging, not for loudness.

[Aotoyota]

what xover poing are you using for the tweeters?

and I think you are making a false stage really, if you want a solid stage,
the general rule is that the more equadistant that the speakers to the driver the better,


with two sets of tweets out of phase, you are causing some cancellation between the two. how? the ones in the corner are firing into the windshield and causing a hard reflection into the cabin, with the tweets in the A pillar out of phase ( or vice versa) cancellation of certain frequencies that are splashed off the windshield. the end result is good but way too complicated.

if you want a nice solid stage edge try a single set of tweets, and double stick tape them eye level and see how they sound. I remember listening to Richards i20isolara car a long time ago, and that was my general impression.

let us know if it works, or if anyone has the time to try it.

[MisterTedster]

^ I did try it. With a single set of tweets, I couldn't achieve the fill and sound stage I was looking for. Essentially, the audio coming from only one set of tweets was too directional. Also, the only way to really place the tweets equidistant from the mids is to place the tweets within 6" of the mids. Just the stock location or eye-level on A-pillar alone are not good placement. The other issue is driver position. Everyone drives in a different position, hence placing tweets on the A-pillar may be satisfactory imaging for one person, but not for another.

I'm trying to achieve a the widest, fullest sound stage possible with accurate sound, while maintaining practicality (ie. not interfering with the driver's view) and being sure that everything is reversible (ie. no holes in the dash, A-pillar, etc.)

My xover is at 3.5kHz for the tweets, 3.5kHz-80Hz for the mids, and 80Hz and below for subs. I'm still playing with the tuning, and these are only baselines.

[Aotoyota]

hmmm if we ever have another socal meet, i would really love to audition your car!

have you tried flipping the phase on the tweets in relation to the mid? and what tweets? try lowering the xover point, maybe there is a phase issue bc of the locations of the tweet and mid...

and can you fit a 3 or 4" mid in the corner? my buddy and I did this on his 09 civic with the tweet in the triangle on the door. that car sound phenomenal.

and if you have access, maybe a RTA will help.

finally.. pics! pls

[MisterTedster]

I've done the following combination of phases:

1) all in phase
2) all left in phase, all right out of phase
3) left mid and left stock (location) tweeter in phase, left dash tweet out of phase, right mid and stock tweeter out of phase, right dash tweet in phase
4) all in phase, both dash tweets out of phase

I will be repointing my mids using an angled 6.5" mdf ring to see if I can bring my mids up. So I will be playing with everything all over again once I do that. -sigh-

I haven't lowered the xover point on the tweets because I'm afraid of frying them. According to specs, the polk tweets only go down to 4kHz, so I felt 3.5kHz would be as far as I want to go.

[Aotoyota]

one more thing that came to mind. try it without the door panel, might be the factory grille getting in the way of things.

if you have tried that many combos, makes me curious what it sounds like with the two sets of tweets.
good luck.