The B&C will have nearly no midbass in the car door compared to the Seas. It's absolutely terrible at that. The Seas on the other hand has stellar response down low. Not exaggerated, but it's very composed.

Higher efficiency = smaller bandwidth.

If you truly need the output of pro audio gear you need to start determining what your compromises will be. A pro audio setup will require more than a 2 way or some extreme measures to make it work and by extreme I mean you'll need a horn and compression driver on the top end. Pretty much no way around that. Even then, I'd prefer at least a 3 way, but it's a car so a compromise is necessary.

6" & Pro Audio with the words bass or midbass should NEVER exist. When someone starts promoting that as an alternative they are either not very well educated, partly deaf, stupid, or trying to steal your money.

One other misconception is the use of PA drivers. Nearly all of them are designed to work in large ported enclosures. Good luck fitting that in your doors.

I don't doubt what you say about the different drivers, but what specific qualities or t/s parameters show that the Seas will have good midbass? Or rather what shows the b&c will have no midbass?

I'm confused. Doesn't bandwidth and frequency range go hand in hand? Or am I being misled by the seemingly good frequency response chart of the b&c? Not to say that the Seas isn't good as well.

I'll keep this general. Power ratings are usually given at a crosspoint that is 2-3x Fs. In particular true for pro audio. You also trade off sensitivity for frequency response so if it's more sensitive, you can see the roll off up nice and high, that ought to tell you something. The hope in the pro audio realm is that you can make up for some of the lack of low frequency capability with enclosure. Being they are limited in excursion this is really the only way. Mounting one IB will cause it to unload like crazy and really ruin not only it's lower end but the higher as well. Doppler distortion then also comes into play. (ie cone moves like hell at a low frequency while trying to play a high causing modulation on the wave and doppler interference in the output).

And yes bandwidth is frequency range, not related but exactly the same thing.

I am curious how your goals landed you looking at B&C? In general I am a huge B&C fan, but implementation details are critical once you pick a driver like that.

What you say makes sense and seems logical. The xmax on the drivers is the same, but I assume the unloading would still be problematic and make this speaker unusable in this application.

To be honest, before this thread I just had a list of drivers to check out as I learned more and more. I wrote down different drivers from builds I saw of people with similar goals and door applications and it happened to be on there. I was also looking at the Seas ca18rly which is pretty similiar to the er18rnx.

I also like to scroll through madisound and parts-express when I'm bored.

Edited October 24, 201212 yr by stiffler style

What you say makes sense and seems logical. The xmax on the drivers is the same,

They aren't. The B&C's Xmax is rated as peak-to-peak, not one way linear. So the Seas' Xmax is actually twice that of the B&C.

How do we know? Pretty easy, in this particular case, since both manufacturer's list the height of the magnetic gap and the length of the voice coil. The most simplistic definition of one-way linear Xmax is VC Overhang/2, we can use this information to compare the drivers "rated" Xmax.

The B&C has a gap height of 6mm and a 12mm long coil; that only leaves 6mm of total coil overhang which when divided by 2 would be 3mm of one-way Xmax. The Seas on the other hand also has a 6mm gap height but has an 18mm long coil; 12mm of total overhang or 6mm of one-way Xmax.

It's deceiving and if we didn't have that little tidbit of information about the coil overhand we wouldn't be the wiser.

Aside from that, M5 hit every nail on the head. A 6.5" pro audio mid is not going to work well in a 2-way....midbass response will be non-existent.

I feel pretty dumb now haha. I assumed the b&c was one way because it has the +- in front of the 6mm and the seas has 12mm (p-p).

So the Seas er18rnx might be the best option. What do you think about the other seas drivers? such as the ca18rly, ca18rnx, or the u18rnx?

The rly series seems to have a higher qts which might yield better midbass in a door.

Run from the rly. Didn't realize they still even made it. Thought the rnx displaced it 5 years ago.

And there is no "best" option. Everything is a compromise. If you say best, you should surely clarify for what as there are a ton of other drivers that will do some things better than the ER. I cited that driver as a solid recommendation based on a few factors: easy as hell to integrate (this is huge for those with no experience and may outweigh all other parameters), fairly large frequency range, good midbass capability, no major cone breakup (at least where it would be used) and it's cost effective for a driver that is designed so well. Does this make it the best? Hell no, can it be a great choice for you? Perhaps.

My main concerns are midbass output and mating up with a tweeter. I haven't really seen a driver that has the good frequency range of the rnx but would have better midbass output.]

I've been thinking too. I could (I say that with a little hesistation) fit an 8" driver however it would have to be right around 3" deep so I can mount it so there is a little room between it and the door card. The door card would be covering a little bit of the driver as well. Does that open up any better options off the top of your head as far as drivers are concerned? Maybe an 8" driver could provide the midbass output and the frequency range I am after.

8" driver in a 2-way is generally a bad idea unless you happen to find a tweeter that can handle a very low xover point, which would necessitate a large format tweeter, or you go with a wide-bander up top (I think that might have been discussed in this thread already?). The short story is that it would be better, especially if this is your first attempt going active, to stick with your original plan of a 2-way with a 6.5" - 7" mid.

Couldn't agree more.

Okay. I didn't know if an 8" would open up better options or not.

So should I keep looking at drivers or do you think the er18rnx is a stout driver for my goals and limitations? How would the u18rnx compare to the er18rnx?

What are your thoughts on these tweeters: lpg 25nfa, seas prestige 27tffnc/g, morel mdt22, and sb acoustics sb26stac-c000-4? Opinions on any of those?

Edited October 25, 201212 yr by stiffler style

Thoughts are related to mounting location

Can we consider both mounting locations? As in, which one would work best in the door (size isn't much of a constraint as I can fit most any tweeter here.) Which would work best in the sail panel? (1" or smaller) I've come to find that the stock tweeters are aimed across the car. I might have moved them a bit when I was looking but it seems they are aimed at the opposite seats headrest.

I don't really feel like writing a dissertation for you.

As for the pillar are you willing to make a custom mount up there? Diameter wise I doubt the Seas or the LPG will fit in most stock tweeter locations. Between those two the Seas plays lower and the LPG has better off axis response. Completely different sound. The LPG will need a mid that plays really high as I personally wouldn't use it below 4k. The Seas can play deeper but will roll off on the high end in particular off axis. Not my favorite Morel and I've never used that SB. I can peak at the specs of the SB later, but until you narrow down where you want to install things it really makes no sense.

I can custom make anything as long as the appearance is stock. I'll see what I can fabricate in the panels and what I can fit up there. If not, then I'll be stuck using a very small format tweeter or going back to the doors with off-axis.

Update: I should be able to mount any small tweeter behind my sail panels and can aim them somewhat. The stock aiming is at the opposite seats headrest but I can turn it depending on how big the tweeter is. I figure the next step is to buy speakers and see how it turns out.

Aren't so many small format choices so conveniently that narrows things down. If you need frequency extension, the Seas Neo. If not, there are more choices or if you up the budget alternatives as well.

If I wait until the end of December I can up the budget and that gives me more time for other projects. I like the seas neo so I'll end up getting that and trying it. It should be fine for what I'm trying to do.

Make sure to play with mounting angles. They will NOT sound nice on axis...

Are they going to sound better closer to on axis (15 degrees off) just not on axis? Or rather the opposite (+60 degrees off)? I just need a starting point and from there I can work off of it.

That'll depend on your car, the reflections, the installation, the processing, the frequency range, your preferences and a bunch. Last time I aimed some I tried a ton of aiming options.

Come up with some songs you don't mind listening to a lot, then get some double sided tape and mount your tweets on the sail panels. Listen to it for a while on multiple songs, then re aim and tape them and repeat the process. Eventually you will find an aiming that is suitable to "Your" ear, and then you can mount them more permanently. I like to do the demo process over a few days, so that my ears have a chance to rest between sessions.

Your days are my months. I'm slow to make a "permanent" decision, lol.

Permanent in quotes because then of course I like to change things.

Your days are my months. I'm slow to make a "permanent" decision, lol.

Permanent in quotes because then of course I like to change things.

Im being optimistic. I still don't have my highs permanently installed. Because I know I'll want to change them. Which I must did a few weeks ago. And I think I want to demo another set before I make a "permanent" choice.