[Forddenial]

I got bored and decided to see what all this talk was about Midbasses, so I clipped some wires on my Kicker KS693's. Wrong wires. I thought I had killed the 6x9's so i went and looked for some cheap replacements.
Behold, the Kicker RT67. Too small of a sub to actually BE a sub, but not built to play midrange frequencies.
Fabricated some brackets out of some scrap MDF to replace the 5x7-to-6x9 brackets.
Dual 4ohm voice coil, 150w rms, frequency range: 30hz-500hz
Perfect for a bridge between the midrange (what you think of when you hear "speaker") and the subwoofer

Wired them parallel for 2ohm impedance to take advantage of the power capabilities of the Soundstream amp.

 

[Forddenial]

Around this time I acquired a beauty of a sub: the Adire 12KH501d2. I also built a different box for it because the box for the Diamond sub was too small...and for a 10" sub, not a 12".

I decided this would be a perfect time to swap out the Kenwood amp with a Mercury Audio C800 as well.

Fitting the new power/ground wires. New amp, new wires.

Adire sub and box. I used 3/4" Birch plywood, double top baffle. 1.32cuft (gross).

Ran new wiring for the midbasses in the rear deck, new (matching, I have a touch of OCD even with what can't be seen) RCA's and insulated the rear dash using pipe insulation "tape" on the high spots to prevent rattling.

 

[Forddenial]

Gain setting the Mercury amp.
These are the o-scope readings, you can see the frequencies in the bottom right of the scope's screen. This amp has a subsonic filter which is basically a high pass filter - it cuts off frequencies below a set point. The Mercury's cutoff is around 15hz because the sub's excursion (how high the voice coil can rise in its channel without jumping out and causing damage) limit would be dangerously exceeded at frequencies lower than that.

With this knowledge and with the sub's voice coils wired parallel for 1ohm, we can do the following math to determine the wattage going to the sub.
Remember Watt's Law: V^2 / Ohm = Watt
20hz 24.3^2 = 590.49w
30hz 32.8^2 = 1,075.84w
40hz 31.8^2 = 1,011.24w
50hz 29.3^2 = 858.49w
60hz 22.5^2 = 506.25w

Now we go to the final aspect of tuning: measuring response using acoustical sweeps.


Forgot:
I have the Front channels on Highpass filter from the HU at 250hz
Rear channels Highpass from the HU at 120hz, Lowpass from the amp at ~300hz
Sub channel Lowpass from the HU at 100hz, Subsonic from the amp at ~15hz

 

[Forddenial]

Initial tuning

The way an Acoustical Sweep works is by sending a 20hz-20,000hz sine sweep through the speakers and then it is measured by a calibrated microphone to produce this:

I did this on my phone using the Dayton iMM-6 calibrated microphone and the Room Acoustics Meter app (Android) and I also used the AudioTool app ( Android) for live RTA info to aid in the equalizing process between RAM sweeps.
Microphone and home-made stand:

RTA screenshot

The goal in all this is to use time alignment to balance the signal coming from all the speakers to hit the listening point (driver's seat) at the same time and thus provide as "perfect" a listening experience as possible

I'm not going to bore ya'll with the details, but as of 12Feb2023 this is where my system is at:
(Ignore the pink lines, the Red and Blue are the important ones. They are the main Left and Right signal readings)

You can see that there is a separation between 100hz and 600hz which tells me that i need to go back in and play with the rear speakers' alignment settings

This is pretty much where I'm at right now. I've been busy with my home audio projects and customer projects so I haven't gone in and done a recent sweep. I also have recently installed REW (Room EQ Wizard) on my laptop, so we'll be having fun with that too.

 

[Forddenial]

System demo video and old school excursion show

 

[Forddenial]

Running ideas through my head about completely re-doing my amp setup...
This time I'm planning to use some of the "collector" gear I have in the closet.
3x Soundstream D100ii
1x Soundstream 1000SX

This build will actually involve
1) Basically building the Steeda rear seat delete cover out of wood
2) Running all the speaker wires that are currently laid in the car to a terminal strip (left bottom of drawings)
3) Running all RCA's that are currently laid in the car to an equivalent "terminal strip"
4) Installing busbars/distribution blocks for the power/ground wires

This way I can swap out/move around the amp layout and I'm no restricted by the lengths of wires currently installed. All I have to do is run appropriate lengths from the terminal strips to the amp positions

Without a DSP

With a DSP

 

[Forddenial]

Some other little playing around I did:

Been running the Adire 12KH501 (dual 2ohm) for a while, swapped it with the Blackmore BWX-12DV (dual 4ohm)...

I swapped in the Diamond M612d4 and TDX10d4....
10" to 12" adapter for the TDX

M612d4

Notes
The TDX is similar to the M612 but can't go as low. Has alot more rms capability in the same size box (1.1ft³ net), just sacrifices the low-low notes. The M612 is very similar to the KH501 (except the KH501 is dual 2ohm and is being run on twice the power) and the KH501 can go even LOWER that the M612. It's a toss-up as to which is my favorite.....🤬🤬

 

[Forddenial]

Forgot to add this bit:
My girl is in for the long haul, i know it.
Made ONE MENTION of another guy's breaker setup and how cool it would be to have one so i can just pop it to work on my electrical instead of pulling a fuse out of a kinda awkward spot

This showed up in the mail:

So I got to work making a bracket. This metal piece came from a fried jumper pack that I dismantled and scavenged from. The little holes were preexisting and were actually the perfect size/distance to mount directly to the same holes I had made for mounting the fuse block. I tapped some new holes in the steel and bored the mounting holes in the breaker a size bigger so i could use T-nuts as alignment posts as well. JB welded the T-nuts to the bracket and now I have a breaker block instead of a fuse block.
Breaker rating is the same as my fuse rating. It was around $20 on Amazon so if I put in a system that draws more power it's not a big deal to swap it out with a higher rating.

In order to Future-proof my system some more, I added the following 4ga (OFC) wire runs while to reinforce the OEM runs:
Alternator + to fused Battery +
Alternator - to body grounding point for Battery on strut tower
Engine block to body grounding point for Battery on strut tower (with HSI heat shield)

 

[Forddenial]

Here's where i'm at. Looking for a 6-6 (3pair-3pair) rca distro block since the wires i have already run might as well be used. Custom rca's from the block to the Helix and from the Helix rca-out to the amps.
Top of seatback is 46", bottom is 42 1/4" (wasn't paying attention and started placing amps upside down)

 

[ab_mach1]

Nice layout and system! I had a Soundstream 4 channel amp in my 90 Ranger extended cab. I had an MTX sub box setup, but I can't remember the exact amp I used for the box. It might have been an MTX amp. This was back in 90-91 lol, so no pics. I really liked the Soundstream amps because of the sound quality and power vs size. I think I still have the Soundstream box where you'd put in a chip/resistor (something) to cut off very low end to speakers when you had a sub setup. If I had changed my system in my Mach, I was going to go with a Soundstream amps to eliminate the Ford Shaker amps. Mine would have been very low key compared to yours lol.

 

[Forddenial]

I don't know what it is but I've developed a "thing" for Soundstreams 😅

Just gonna leave this here for a sec

And I also like to challenge myself. This new setip involves a DSP which is basically a customizable computer sound card for each and every speaker, including the sub.
I've always used EQ's (did one for a customer with an EQ each for left and right...that was fun) or passive or powered crossovers (I have passives for my midranges and tweeters right now).
Plus I want to see if this old Class A/B gear sounds as good as it's supposed to. If not I can always redo the setup again and make up and excuse to buy ANOTHER amp (only have somewhere between 7 and 10 or so right now).

Thanks for the compliment, too!

 

[Forddenial]

Language Warning (Rated PG)​

In case ya'll were curious about how installers did racks before they had CAD (😄)