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Discussion starter · #23 ·
Yeah, it's an iPad, that will happen, lol.
...can't even blame the iPad this time, it's YouTube. Well, me, because I used music in the video they've banned it in some countries and on some platforms. Looks like I need to make a new video:)
 
Discussion starter · #24 ·
It's been a long time, but here are some more updates...
Not 100% impressed with the sound of the center channel I noticed a small area of dash which hadn't been butchered, and more importantly had nothing behind it... Cue the soldering iron and heated knife blade.
It now houses an old school 7 band graphic equalizer solely for the center channel, back-lit by several colour morphing LED's. Easily reachable whilst driving, so any song which requires a bit of tinkering can be done on the fly, not like those ridiculous boot mounted EQ's which require you to pull over to adjust in pursuit of the perfection you'll never find.
Another sizeable modification is the addition of a leisure battery in the boot, purely for the head unit, monitors, bass adjusting circuits and center channel amp, so they all have their own clean power supply. It's charged whenever the car battery is above 12.9v. There are 2 separate LED volt meters mounted beside the boost gauge to monitor the voltage before and after the switching circuit used at 12.9v.(ignition switched) Below that voltage the 2nd display reads 0.00 and the first will read the vehicle electrical system's voltage, but once the engine is started the 2nd display shows the charging voltage into the 2nd battery (minus whatever is being drawn by the connected devices). The switching circuit output is also connected to 4x 40amp relays so that when activated the 2 batteries are pretty much connected. A separate 0gauge cable has been run just for the charging of the leisure battery, a bit overkill I know, but I manages to acquire a 15m roll of it for around the same price as an 8gauge wiring kit so thought I might as well use it :)
Goodbye PIAA switches... These have now been replaced by 7 touch sensitive panel switches, the bottom four of these do the same jobs the 4 old switches used to do, but with the addition of the extra battery the top three all have new tasks...
The head unit is fed directly from the leisure battery, but through an ignition switched relay, so even though it isn't connected to the car it is still controlled by the ignition. Until the top switch is pressed, then it bypasses the ignition relay so it can be on without anything else (all amplifiers are still ignition controlled) but the 2x volt meters beside the boost gauge have their own relays bypassed too, so now they show the voltage of battery 1 and battery 2. The top switch is active and illuminated red all the time, even when the car is locked and everything is inactive, but Once the top switch is pressed the two switches below it turn red too, one is for an adjustable 2.1amp voltage regulator for my electronic cigarette, it's set at 5.1v and connected to 3 different phono chassis sockets around the car which it plugs into, using a modified usb passthrough adapter. The same 5.1v 2a supply is connected to a USB port beside the center speaker for charging my ipad, at the same time as the JVC charges my iphone or iPod.
The third switch from the top turns on both inverters, one of which powers the stripped down and re-housed PC, the other supplies 220vAC to the trailing mains socket behind the passenger seat, and the monitor socket (IEC) beside the passenger seat, in a small box which also houses a vga (d-sub) socket and a HDMI socket, which are all used for the 24" LG 3d computer monitor, vga is fed from the pc. The HDMI, which is for the xbox 360, which can either be plugged in behind the seat or in the boot.
Audio for the PC or xbox is played through the rear speakers. A small toggle switch has been added on the rear of the center console which turns on a roof mounted Bluetooth receiver with an aux input, powered by another voltage regulator set at 9.4v 3a. Audio input is connected directly to the pc and also to 4 x phono plugs, 2 In the front and 2 in the rear so any set can be used for the rear speakers, which are disconnected from the head unit whenever the ignition is off through 2 x 12v DPDT relays as the speaker outputs from the "blackbox" Bluetooth can't be connected straight to the outputs of the headunit as an 'off' amplifier would create a massive load across the channels of whichever amp is active, hence the need for the relays. (been there, done that, not ideal) the xbox can actually be played whilst the vehicle is in motion by the rear seat passengers, albeit not in hd, through a separate 15.6" drop down roof monitor which has been modified to sit in the back edge of the sunroof recess, with audio still powered by the blackbox, through the rear speakers which are disconnected from the headunit by the toggle switch/relays.
The drop down screen has a din plug connector which is normally hidden in the rubber for the rear door, but pulls out to just the right length once the monitor has been slid into place. As this is rarely used the 12v supply for it is a direct 3a fused connection to the vehicle battery with no switching. The monitor has 2 inputs, one is for the xbox and the other terminates at another phono chassis socket between the front and rear doors, with a modified cable in the seat back pocket which has a phono one end and an apple dock plug on the other, so video from the iPhone can be sent to the 15.6" screen while the audio gets Bluetooth'd straight to the blackbox then on to the rear speakers.
The last update has been the subwoofer...
I'm still using the same 15" vibe black air driver, but it's not in an enclosure any more. Cue the jigsaw... The parcel shelf had the entire middle section removed and replaced by a piece of 18mm chipboard with a vibe shaped hole in the middle, glued braced screwed and siliconed in place to make it able to support the 15" drive unit, then all the contours were filed and smoothed out, then it was covered with acoustically transparent cloth to look like just a boring old flat grey original-ish shelf. Then came the trial and error. Turns out you can't mimmick a speaker enclosure with an entire boot, especially when you're not using a free air subwoofer. But with enough polyurethane foam you can balance it just enough the present enough reflected air back at the bottom of the cone at the same time as just enough sound waves can escape... It results in a sound which doesn't have the boominess or the reverb of bouncing around the boot then through the shelf, then reflecting off the rear window before making its way to your ears, all of which makes the driving beat of a song sound somewhat out if time when using a typical bass enclosure.
Now, however, it's all tied in, it sound as if all the speakers in the car are complimenting each other and reacting to the same signals all in time, no delays on the bass, and the only evident delays are the ones I've manufactured using the time alignment of the headunit.
The only flaw in the system is the fact that the sub can now bottom out, and reach xmax more readily (xmax : maximum excursion of the voice coil) but this can be remedied by using the bass effects system I designed in the first post, as it double layers the bass frequencies and makes the bass seem somewhat "more" even though it's not.
-The bass effects also sound much better since I threw the enclosure away, as the sub was always trying to produce two sounds at the same time, which resulted in (I assume) stray waves and pressures inside the enclosure hitting the rear of the come and distorting the sounds it was trying to create, which in turn coloured the next wave, and the next, and so on... But now it's clean. Controlled. Tight. Deep and somehow -proper....
Even though it's not, at least not the way it was intended, somehow it's better though.... :)
 
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