You guys won't believe this. My stereo install.

[lithiumus]

Rather than find a tweeter to match the mid, I'm sure a high quality passive crossover can be built for the speakers you have already chosen. Of course it won't give you the ability to adjust the crossover point, slopes, time alignment or all the other speaker protection logic the Front Row gives you, but at least it opens up the options once you've found the proper crossover points and slopes.

When you start to narrow down your crossover points and slopes, send me the info along with the speaker specs and I'll see if I can design a fairly high quality DIY passive crossover option. The Aura speaker has good specs and an impedance curve showing the VC inductance... that's a good start. Send me the tweeter info and if we have the VC inductance info as well, I can start some draft passive designs with your xover points and slopes. The goal would be instead of going from 90 to 50 with different speakers... but maybe 90 to 70 using the same speakers.

Are you counting the tweeters as 2 items and the sub as 1 item to make 3? Just making sure there wasn't a component that I'm missing.

What is the bass response without the subs and just your high excursion mids properly crossed over with subsonic as well? No sub may also be an option.

 

[sschnell]

Cant wait to see some more photos

 

[gleibig]

Can you throw out a ballpark number that this whole system may cost? Are we looking at closer to $500 or $5000? That would factor into how closely I keep up with this thread.

 

[TURBO2GO]

Can you throw out a ballpark number that this whole system may cost? Are we looking at closer to $500 or $5000? That would factor into how closely I keep up with this thread.

I'm guessing and this is REALLY ROUGH.... between $500-$1000 for all the drivers, enclosures, adaptors, door plates, etc.

$300 or so for electronic crossover and then whatever amp you pick. I'll try to get more specific later.

 

[bngl3rt]

I'm guessing and this is REALLY ROUGH.... between $500-$1000 for all the drivers, enclosures, adaptors, door plates, etc.

$300 or so for electronic crossover and then whatever amp you pick. I'll try to get more specific later.

Considering that's what SoS charges for their "audiophile" system and this is sure to sound better (not to knock SoS, their work was an important stepping stone on the way to what'll come out of this...), that's a great deal.

 

[TURBO2GO]

The issue is I have to hand build a lot of this stuff unless I have moulds made and have the parts reproduced on a larger scale. I'm hand building the speaker plates, which are an unusual shape, even more so than what I posted a picture of. I have to hand build each bass tube, inside is baffling, two types of insulation, painting the pipe, I have to tap 24 bolt holes perfectly straight, lots of glue, etc. so it's time consuming. If I was to get a group buy of say 10 and build them at once that might make it easier. I suppose I can have moulds made of the door plates but I'm not sure who would do that.

But I might be getting ahead of myself. Let me get the system fully designed and into the car before its too cold to do any of this and the car is put away.

 

[TURBO2GO]

Rather than find a tweeter to match the mid, I'm sure a high quality passive crossover can be built for the speakers you have already chosen. Of course it won't give you the ability to adjust the crossover point, slopes, time alignment or all the other speaker protection logic the Front Row gives you, but at least it opens up the options once you've found the proper crossover points and slopes.

When you start to narrow down your crossover points and slopes, send me the info along with the speaker specs and I'll see if I can design a fairly high quality DIY passive crossover option. The Aura speaker has good specs and an impedance curve showing the VC inductance... that's a good start. Send me the tweeter info and if we have the VC inductance info as well, I can start some draft passive designs with your xover points and slopes. The goal would be instead of going from 90 to 50 with different speakers... but maybe 90 to 70 using the same speakers.

Are you counting the tweeters as 2 items and the sub as 1 item to make 3? Just making sure there wasn't a component that I'm missing.

What is the bass response without the subs and just your high excursion mids properly crossed over with subsonic as well? No sub may also be an option.

I am down 6db around 65hz with no subs, outside the car. I don't know yet what it'll be like inside. I am certain it will extend lower.

What is your insistence on going passive? The wire in the door isn't all that proper either. Time alignment is big, I don't want to lose it. You want to do all of this so that a 3-4 channel amp can be used instead of a 5/6? You can always get a second amp to add to your 3/4. Add a small amp for the tweets. This is the one area I just can't compromise the system unless I start to defy the laws of physics.

Oh and another thing.... I need some really steep filtering. I much prefer to do that in the digital domain.

 

[TURBO2GO]

Considering that's what SoS charges for their "audiophile" system and this is sure to sound better.

Add up the weight of the long wire runs, the radio, the door plates (4 pounds on their own) and that system is 65 pounds. I'm at around fifteen including amp, crossover, subwoofers, everything. I can guarantee the sound quality will be very different, and the fit is pretty much fully OEM down to the factory connectors. 50 pounds less weight in the car. I'm lighter than OEM.

 

[bngl3rt]

The issue is I have to hand build a lot of this stuff unless I have moulds made and have the parts reproduced on a larger scale. I'm hand building the speaker plates, which are an unusual shape, even more so than what I posted a picture of. I have to hand build each bass tube, inside is baffling, two types of insulation, painting the pipe, I have to tap 24 bolt holes perfectly straight, lots of glue, etc. so it's time consuming. If I was to get a group buy of say 10 and build them at once that might make it easier. I suppose I can have moulds made of the door plates but I'm not sure who would do that.

Santa doesn't do all the work by himself. He has elves!! :biggrin:

 

[haveblue]

How much do you estimate the weight of OEM is?

 

[TURBO2GO]

How much do you estimate the weight of OEM is?

I didn't measure everything but I'd guess 25 pounds or so not including cd changer. That's about 11 pounds by itself including bracket. It's dead weight and a space hog as far as I'm concerned. It's like the cell phone. Time has passed it by.

 

[lithiumus]

I am down 6db around 65hz with no subs, outside the car. I don't know yet what it'll be like inside. I am certain it will extend lower.

What is your insistence on going passive? The wire in the door isn't all that proper either. Time alignment is big, I don't want to lose it. You want to do all of this so that a 3-4 channel amp can be used instead of a 5/6? You can always get a second amp to add to your 3/4. Add a small amp for the tweets. This is the one area I just can't compromise the system unless I start to defy the laws of physics.

Oh and another thing.... I need some really steep filtering. I much prefer to do that in the digital domain.

That's pretty low as it is and might be enough for some...

Passive eliminates the electronic processing cost and going from 5/6 to 3/4 or even just a simple 2 channel would be desirable esp. if you are still getting much better sound quality than OEM.

Personally, I'd still do a sub and a separate dedicated center channel for Navi but sometimes simple is a desirable route... maybe not.

Are you looking for 24db/oct or more and is it for just the tweeters or both the tweets and mid?

 

[TURBO2GO]

That's pretty low as it is and might be enough for some...

Passive eliminates the electronic processing cost and going from 5/6 to 3/4 or even just a simple 2 channel would be desirable esp. if you are still getting much better sound quality than OEM.

Personally, I'd still do a sub and a separate dedicated center channel for Navi but sometimes simple is a desirable route... maybe not.

Are you looking for 24db/oct or more and is it for just the tweeters or both the tweets and mid?

I might wind up using a Front Row (have one on order) and that cost is about $280. It gives me subsonic filters, which I really need with these small drivers.... It gives me time alignment, 48 db/Octave crossovers, a remote bass and stage width adjustment, and band pass and high pass for the doors. All done with quality DSP's in the digital domain. It is an incredible bargain. I am not sure trying to save money here by going passive is worth it, the labor time alone to make these passives nevermind parts. And then to lose everything else. Just not worth it Garrick. If I was spending a grand on active x-overs that'd be one thing but we really aren't saving much going passive. And we lose all the flexibility and quality. I can't "tune" with a passive, no matter what software you use to design it, it may not be perfect and then it becomes a big trial and error kind of thing.

 

[bngl3rt]

So I understand you're still working out the specifics, but the basic template appears to be coming together:

(source of your choice)
TO
in-dash volume control flush mounted OR processor with wired remote
TO
6ch amp in passenger footwell under carpet, cooled by aluminum
TO
great tweeters at the bottom corners of the windshield AND low-diameter high-excursion drivers in OEM-fit baffles in the doors AND a bass tube behind the passenger headrests

Does that about sum it up?

 

[lithiumus]

I might wind up using a Front Row (have one on order) and that cost is about $280. It gives me subsonic filters, which I really need with these small drivers.... It gives me time alignment, 48 db/Octave crossovers, a remote bass and stage width adjustment, and band pass and high pass for the doors. All done with quality DSP's in the digital domain. It is an incredible bargain. I am not sure trying to save money here by going passive is worth it, the labor time alone to make these passives nevermind parts. And then to lose everything else. Just not worth it Garrick. If I was spending a grand on active x-overs that'd be one thing but we really aren't saving much going passive. And we lose all the flexibility and quality. I can't "tune" with a passive, no matter what software you use to design it, it may not be perfect and then it becomes a big trial and error kind of thing.

You know, I think you've convinced me. I don't know why I kept thinking this unit was over $500 minimum. Must be those high Alpine prices of the H700 and H800 that completely steered me away from advanced digital processing. At $280, like you said, even if you went with a small amp for the tweeters would negate the cost and effort of a high quality passive crossover system. 48db/oct is super DUPER steep!

Things have come a long way since I was really into car audio... namely price vs. feature/function ratio! (lower prices, many more features)

 

[TURBO2GO]

I have made a bass tube. Still gets pretty low and puts out some decent bass. I'd say roughly on par with the OEM sub a little less loud, but it goes deeper. I am pretty certain It can fit where the OEM sub box was. It fires up away from the carpet just like the OEM.

There's a lot of flexibility here, OEM location, front of seats (and it is so small it is virtually invisible as most of it is hidden by the front of the cushion), and behind the headrests. I have to just test these in the car.

One thing of using drivers this small is they are more directional for sure. They don't have the same off axis bass as a 10" woofer. So you have to be more particular about where you put them and where they fire into.

Need lots of in-car testing. I'll start that as soon as I get them fully built and I will report back the results.

I have more drivers on order.

 

[TURBO2GO]

So I understand you're still working out the specifics, but the basic template appears to be coming together:

(source of your choice)
TO
in-dash volume control flush mounted OR processor with wired remote
TO
6ch amp in passenger footwell under carpet, cooled by aluminum
TO
great tweeters at the bottom corners of the windshield AND low-diameter high-excursion drivers in OEM-fit baffles in the doors AND a bass tube behind the passenger headrests

Does that about sum it up?

Yes, source of choice including factory head unit, in which case there is no "other" volume knob. Probably just use a standard GROM for an input of a phone. Or you do away with it, save the 7 pounds, and use a blank radio plate.

 

[TURBO2GO]

You know, I think you've convinced me. I don't know why I kept thinking this unit was over $500 minimum. Must be those high Alpine prices of the H700 and H800 that completely steered me away from advanced digital processing. At $280, like you said, even if you went with a small amp for the tweeters would negate the cost and effort of a high quality passive crossover system. 48db/oct is super DUPER steep!

Things have come a long way since I was really into car audio... namely price vs. feature/function ratio! (lower prices, many more features)

The Front Row does not have some sort of automatic "analyzer" to correct cabin acoustics, nor does it have an EQ. But I am fairly confident that I won't need them. I am just going to use my RTA's to take some measurements, and I should start out pretty good anyway because my driver placements are correct. Maximum transfer of direct sound and minimum of early reflections=less cabin interaction. I still also have the trusty and inexpensive JBL MS-2. I sent the MS-8 back. As much as I like the unit, it is too heavy and big. 8 channels at 20 watts doesn't help me a lot. Especially because I can't assign all of them.

 

[UnhuZ]

Hi,

i thought the tubes would be longer....what would be the result if the tube would be as long as the width of the seat front cushion ?? In this case, one in front of each seat ?

Thanks,
Nuno

 

[TURBO2GO]

Hi,

i thought the tubes would be longer....what would be the result if the tube would be as long as the width of the seat front cushion ?? In this case, one in front of each seat ?

Thanks,
Nuno

Nuno Ive made about 20 different length tubes. Sealed, ported, single driver dual driver, isobaric, passive radiator. Not so easy making lots of bass with such small (but light) drivers.

The one pictured is just a short sealed version of one driver. If I make one for the front of the seat it will be 14 inches (there is 20 available) and contain two drivers firing into the trans tunnel and the door sill. That gives it around a 3db boost.

 

[bngl3rt]

Just came across this on Stereophile...

http://www.stereophile.com/content/high-end-tunes-go

Maybe we will get something this nice in the new NSX. Meanwhile, TURBO2GO is doing the lord's work

 

[TURBO2GO]

Well the front row has shipped finally.hopefully I'll have it soon and be able to put up a full mock up system on my bench.

 

[TURBO2GO]

I was kind of tired of hauling around some of my gear in and out of the car and decided to download an RTA app on my iPad, use and compare it and see how well it works..... I CAN NOT BELIEVE how accurate this $5 app and the iPad2 microphone actually are. I am astounded. I would definitely recommend this! Here is a screen shot of the app:

 

[02#154]

Thanks for all the work you're doing for the community, Turbo. I wish I had the know-how to do what you're doing. Here is my feedback. Please take it only as my personal opinions... I don't want to get into a big argument about little things.

For my aesthetic tastes, I really don't care for the placement of the egg shaped tweeters below the windshield. You say they are not noticeable, but anyone looking at the pics you provided would likely disagree. I don't think anyone looked at your pics and thought to themselves, "hey, where are the tweeters?" :tongue: With all of your testing and measuring, I'm sure that sonically, they are placed as optimally as you can get them, but they just look like eye sores to me. Maybe to an "outsider" they're not noticeable but if you own an NSX you'll always know they're there.

Unlike many (all?) here, I don't care about cutting the car interior. Because of my personal attachment to my car, I know that I'll never sell it so I have no concerns for resale value or what "the next owner" might frown upon. So, would I be able to use your system and have the tweeters custom mounted by a professional installer in the dash, flush, and firing into the windshield? I feel like I may introduce some sonic anomalies so knowing my criteria, what would you recommend for me? I wouldn't mind cutting the door and running wire into it, either.

I like the work you're doing with the various iterations for the subwoofer solution. It's obvious you care a lot about the sonic clarity of the lowest octaves. That said, in my opinion, a lot of people don't really know the bottom octave(s). They consider 45-60 hz to be super low because that's where the "bass" in a lot of popular music is centered. If your door speakers are down 6db at 65, how gradual is the drop? It's possible that, like me, that might be low enough. My musical content is the aforementioned popular music and I wouldn't mind missing the bottom 1.5 octaves because 1) I usually listen to my music so low that the drop might not be as noticeable and 2) I might not like the look of what your solution ends up being. I'm looking forward to seeing you final product.

Lastly, I'd like to echo what another member said in that I don't much care for what a flat frequency response sounds like. To me, it looks nice on a graph but it just doesn't sound right. I know what you said about listening to it for a while and learning to like it but I could just as easily say that you (and other audiophiles) have simply learned to like the sound of what the computers tells you sounds correct. To my ears, "correct" sound does not equal "good" sound. This is the part I don't want to argue about. My ears are mine and, just like me to you, you can't tell me what sounds "good" to me. So that said, would I be able to EQ your setup to my liking? Does the gear you have in mind for use have tuning capability? I know ill probably EQ it to a place you would think sounds horrible, but could I do that if I wanted?

I re-read my paragraph above and don't know another way to say it so I hope you do not get offended. :smile:

J

 

[angus]

I am really interested in seeing the bass tube, not specifically for the NSX but maybe for the 355, this has a boot cover to hide the tube.

As far as hiding the amp in the stock radio - it seems you only need the faceplate since you just need a volume control and you can bracket the amp behind it - rather than encasing the amp inside the radio enclosure.

I did once want to use the OEM faceplate to control an aftermarket CD player, but I am now leaning towards your idea of no head unit in some recent installs.