NB Miata Speaker Upgrades and Road Noise Reduction?

Hi all,

I'm looking to replace the speakers in my NB Miata with something decent, as the current ones are TRASH. I do have the door tweeters so my thought was just to order some components with built in crossovers, like these Focals from Crutchfield. Is that wise?

First follow up: should I get baffles for the woofers? I saw them recommended somewhere for use where water might get in, like doors...

Second follow up: I wouldn't mind making the Miata a bit quieter inside. I know I can only do so much with a fabric roof, but I was thinking some sound deadening mat on the inside of the door skin would help. Is that true? If so, how much would I need? Crutchfield has a two-pack of 10" square sheets I was considering.  Would I use one sheet per door? Or could I use part in the doors and the rest on the rear bulkhead?

Putting a square on the door skins does help a lot (no experience with a Miata here though).  The sound it makes when you close the door should change a bit also.

The heavy tar type deadening is primarily for killing any "drumming" in flat panels.  If the panel has lots of reinforcing bends, it will not help much.  To kill sound otherwise, you will need simple padding (e.g. jute padding).

The MOST important thing in sound deadening is air leaks!  Make sure there are none (gaskests, seals etc).  Should not be much of an issue with a Miata, but you never know.  As noted, the soft top makes putting a lot of effort into this a bit futile.

Any thoughts on the speaker choice?

Any decent 6-6.5" speaker from Crutchfield should do. The Focals you linked are certainly good speakers, but unless you go nuts on the sound deadening and all that, might be overkill on a Miata.

Don't forget that most components really want a separate amp as well.

Re baffles, I'm definitely putting some into my NA. Haven't done so yet but whoever fitted the speakers to my NA didn't put any water protection on the speakers. I'll have to dig up where I got mine from (probably Amazon) but there are a bunch of 6-6.5 foam baffles around that are cheap and should do the job nicely.

Edit: Forgot to mention - with foam baffles you can also do away with the "egg crate" sound absorbent foam that one might want to put into the door behind the speaker to absorb some of the errand sound waves.

One other thing to keep in mind is that to do those Focals justice, you'd probably end up plastering sound deadening all over the doors and possibly the rest of the cabin.

Ah, good to know on the Focals being overkill, I don't mind spending less. 

I don't really want to invest in an amp for this car, I'm hoping that replacing the factory tweeters and woofers would be good enough. I wouldn't be adding tweeters if the car didn't already have them. Would it be a waste of my money to go the no amp route? This is a field I know little about, if that wasn't already apparent 

Focals are def overkill, but they sound amazing. The higher end alpine, or infinity might be cheaper and still quite nice. Install them with windows down to make sure the bigger driver magnets clear!

Skip the baffles unless you actually have moisture problems. Get some dynamat/peelnseal/whatever sound deadener and put a sq ft or so on the inside of the outer door skin where the window will not impede it, directly behind speaker if possible. Knock on inside door panels and use just enough to stop it from 'ringing'. Do the same to any interior panels, trunk lids are often noisier than expected, even inside.

When shopping for nice car speakers, always avoid 3-way systems. External crossovers are best. Take time to aim your tweeters and verify polarity. 

Buy a small class ab amp (class d are efficient, but better for subs). Yeah, seriously. Those focals soak up more wattage than even a nice head provides. You will get to realize the extra quality you paid for. 

Look at the drivabeater 3.0 thread.  I did a ~$100 job of stereo and sound deadening and insulation. Came out amazing Lee good and sounded like a way more expensive system that it was. If I remember right I used 8 inch woofers in the doors Factory tweeters a cheap set of crossovers in a Kenwood head unit in addition to some foil backed jute and Dynamat

IMHO trying to get really good sound in a Miata is an exercise in futility.  

That said, when I removed the Bose unit in my NB, I replaced it with a cheap JVC and Pioneer 6.5s in the doors.  I also added one of those underseat compact powered subwoofers behind the passenger seat.  I lost a couple inches of passenger seat travel, but gained a lot of sound that the door speakers just can't provide.  It wasn't a very expensive unit, ~$110 on Amazon, but it was worth it.

As far as noise reduction, some of the folks on M.net swear by stuffing pillows in the 'tunnels' on each side between the trunk and seat belt towers.

Personally, I use earplugs. 

One thing that helps significantly in Miatas is earplugs. Seriously. The foam ones really just drown out the white noise, you can still hear the stereo very well--I actually have found that I could turn the volume down after putting the earplugs in. 

mtn said:

One thing that helps significantly in Miatas is earplugs. Seriously. The foam ones really just drown out the white noise, you can still hear the stereo very well--I actually have found that I could turn the volume down after putting the earplugs in. 

 

QFT

In reply to thatsnowinnebago :

If you don't want to get an amp, get the speakers with the highest sensitivity you can find. On most headunits the power rating is more determined by the marketing department than the engineering department and they don't necessary have the oomph to drive good speakers. I'm currently running the decent speakers in my NA (I think they're Infinities, not 100% sure) off the headunit and it has trouble overpowering the other noises at anything more than about 45-50mph.              

In reply to BoxheadTim :

Is that sensitivity what Ohms measures?

In reply to thatsnowinnebago :

Nope, you are looking for db/watt.

All car speakers should be around 4ohms, ignoring subwoofer insanity. 

In reply to Nugi :

Gotcha, thanks!

I have a 4x100 Kenwood digital amp in my trunk that’s about the size of a paperback book, and probably weighs 1/2 pound.  It’s pushing Focal 6 1/2 coaxial speakers in the doors, and an 8” JL subwoofer in the passenger footwell.  It sounds glorious.  The amp is critical to the performance of the system, there is no way that a headunit can push enough power for clear bass through small drivers in an open-top convertible.  The subwoofer is also very important, as it lets you high-pass the door speakers which improves the sound quality dramatically.

Personally I think that road noise reduction in a Miata is a waste of energy, and just adds useless weight.