New car hi-fi build!

[Marco]

I suppose it depends on what year/model Toyota you have. My old Avensis was much better than my Auris.

No worries on the head unit, however you should defo upgrade those old Toyota speakers, as compared with the JBLs (or any other quality car audio speakers) they'll be piss poor and almost certainly (mostly if not wholly) responsible for that "bright or busy" sound you mentioned.

You have to remember that pretty much anything audio-related that comes as standard in 90% of cars, costs pence to make, rather than pounds - and it shows!

Marco.

[fatmarley]

No worries on the head unit, however you should defo upgrade those old Toyota speakers, as compared with the JBLs (or any other quality car audio speakers) they'll be piss poor and almost certainly (mostly if not wholly) responsible for that "bright or busy" sound you mentioned.

You have to remember that pretty much anything audio-related that comes as standard in 90% of cars, costs pence to make, rather than pounds - and it shows!

Marco.

If I had a nice workshop, i'd use my own selected drivers and build a crossover myself. The Eminence Alpha 6C has a lovely flat frequency response and is far more efficient than the JBLs, as a result they'd have the potential to go very loud with only a small amp. Don't know if they are waterproof, but if not I'd spray some Scotchgard on them. The only thing that stops me is the hassle of it all. Thinking about it, I suppose I could probably design them indoors, but then it would still be a lot of messing about - hmmm...

[fatmarley]

Couldn't help myself. Bought some Eminence Alpha 6C drivers and measured the reponse on a 14" wide baffle nearfield.




If I was crossing this driver at 2khz in a home audio speaker the breakup at 2.5khz and up, wouldn't matter but with car hifi most speakers are run full range with an added super tweeter (the JBL GTO 609C woofer is also run direct). In the end I decided to slit the cone and add some damping compound similar to Scanspeak. I also sprayed some Scotchguard on the cone to try and keep amy moisture out.



With the slits in place the frequency response is much better and just listening to some music with them in a huge box hooked up to my quad 306, they sound much better too! (Some female vocals were a bit nasty before the slits)
Frequency response now looks like this:



I had the mic very close to the cone, so higher frequencies are smoother than that in reality but it does show a good before/after comparison.

Here's a pic of the JBL (RED) compared to Eminence (BLUE). Again I had the mic very close to the cone, so I think the 100hz to 1khz area is the place to look.



The response would be flatter in the car because of the lack of diffraction. Here's a pic of the diffraction from a 14" wide baffle.



As you can see, the JBL already has a dip at 700hz that will be worse in the car. My in car measurements show a large dip at 700hz that badly affects vocals.

The tweeters are now on maximum output (plus 3db) to keep up with the much more efficient Eminence drivers, and the response measures smoother through the midrange (I was in a rush so forgot to take measurements). The sound quality is much better to my ears with vocals sounding much more real and with better presence and projection. I had a bit of a peak at 60hz but luckily my head unit has Eq at that frequency, so the bass is better too (The slight boom is gone). The JBL 609C does extend lower as can be seen in the pics but my sub extends quite high, so it's not a problem (I've still got good midbass).

All in all, i'm very pleased with the sound but it was a lot of hassle.

[fatmarley]

And a rough and ready pic of the JBL GTO 609C in car. The mic was about 4" from the centre of each driver (Red woofer, Blue tweeter).

[Marco]

So, most importantly dude, how's it all sounding? And can we see a pic of the finished install, showing everything in situ inside your car?

I'm pretty much 'there' with my stereo now. There are still some tweaks to do, but just gonna enjoy it 'as is' for a while. The ports I added to the interior shelf space, below the back window (drilled through from the boot), just to allow more bass into the cabin area, made a nice difference.

The low-end extension there now is positively organ-rearranging, and coupled with trouser-flapping mid-bass punch, really makes rock and dance music a RIOT!!

Love watching the glass in my rear window, just above the sub, 'swell' to the sound!

Marco.

[fatmarley]

There's nothing to show Marco. Everything is hidden away.

Sound is pretty good but not 100%. I think upper mids are lacking a touch. They sound a lot better when I fade to the front to avoid rear fill, but I quite like rear fill. I may try to bandpass rear fill to see if that improves things...

[fatmarley]

Upper mids are fine now. Just had to reduce the rear fill SPL. I think that when rear fill was too loud, it was causing phase problems and canceling out the upper midrange.

Being ultra picky, bass is too loud when i'm at a standstill but it's fine when the cars moving at speed. I'm guessing that's something to do with ambient noise entering the car when it's moving and cancelling out low frequencies?

[Marco]

Ok, cool... Glad the adjustments worked out well. Pity you weren't nearer. It would be interesting for us to have a listen to our respective installs, and seeing if we could pick up any tips from each other

Marco.

[fatmarley]

Pity you weren't nearer. It would be interesting for us to have a listen to our respective installs, and seeing if we could pick up any tips from each other

Marco.

Yes, would have been interesting to hear that trouser-flapping bass punch . It sounds like yours is a lot more impressive than mine. Would also have been nice to be taken for a spin in that posh motor too, probably give me a heart attack though

[Marco]

Just a small update to this thread...Got the installer to design me a custom-made 'dustbin lid' sized cover for the sub, made from MDF and finished in the same fabric as the rest of the boot. First, here she is in her naked glory:



Hang on, what's this...





And finally with her hat on:



Fits like a glove...

And with the 'DISCO lights' on...






Marco.