2021 Mirage

I

Impossible Bill

Noob
Starting to work on my DD. System plan is:
Source - OEM head unit, convert signal to digital plus a mobile phone to have digital out with pdt on factory display and steering wheel controls.
Front speakers- Bliesma T34B and Purifi PTT6.5X04.
Sub- Hybrid U12SW
Amp / processor- Harmony 8x12DL

May switch source if i find a unit I like with toslink out. Space is important so sub is in spare tire well snd amp under pass seat.

Tweeters are playing to pick location along with old focal K2P in the door since Purifi won't like that location. Will also be fitting a larger 135A mitsu alternator once i can fab new brackets.

I think that covers current system details, we'll see how much that changes as things progress.
 
Started preparing for PTT6.5 mounting while waiting for tweeter brackets to be machined.
View attachment 17241

Trailer light housings are used to hold the aperiodic membrane in the sill panel. The shape and surface area should work pretty well I think. I made a gasket, cut mesh to fit and bonded with 3M 5200. These are also bonded to the car the same way.
View attachment 17242

A rubber trailer gasket that fits inside the trailer light housing will attach to the kick panel that also has mesh. This will seal and sandwich the membrane material and it wont be too difficult to remove the kick and get the correct amount of damping material between the enclosures.
View attachment 17243

Next will be mold of the floor to start building the kick panels.
 
Started working on the kick panels this weekend. Made my mold so I could I line up the trailer light rubber insert with the housing mounted to the sill. I fiberglassed a Steel trailer light mount to give me a smooth surface and position the rubber gasket. This seals the kick panel enclosure to the sill enclosure and holds the damping material.
View attachment 17262View attachment 17263

Then I routed mounting rings and positioned the baffles. I am using the angle used for the tweeters. Since they are large I bought cheap fog lights on Amazon and mounted the tweeters in them. This let me temporarily place them and adjust their axis easily. (They'll be tackled next now that I have the desired position and the waveguides are done.)
Here's a sneak peek at my WG used for fabrication. They are PLA and once fab is done the metal pieces will be installed.
View attachment 17266

Back to kicks, wrapped in fabric and resined to hold shape. I always use epoxy resin for strength when bonding to plastic.
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Inside was fiberglassed and test fitted again. The OEM stud on the firewall and push clips in the kick panel ate still used and they are formed to the floor and against a support rail. They can only fit in 1 position so the AP membrane will be sealed if they are. In position.
View attachment 17265

I made a recess along the inside edges on the bottom so the carpet and floor mats can be tucked in and look like they belong once trimmed.

Outside being fiberglassed next and will be finished with SEM. I sent an interior piece out for paint matching.
 
Made some more progress on the kick panels. Bondo and sanding, I seem to be the only one that likes the smell of that stuff.
Got the first coat of color on too!
View attachment 17272
Kidding, left over paint from making cosplay weapons for my daughters...and want to see if anyone's paying attention. I may come from the era of speckle paint, fleckstone and krylon on anthing plastic you can pry off but not ever my thing.
I like to put some color on and sand with 220 to make sure they are smooth enough for finishing.
 
Kicks are in...sort of.
View attachment 17297
I need more membrane material than I anticipated. The amount I need is more and creates mounting pressure to compress. I have a few options i think.
1. Bolt in kicks to compress it more. Not too difficult.
2. Find material denser than Rockwooll
3. Compress some material in housing built into kick as baseline. (Looks like 12oz is safe)
4. Add depth to the housing built into sill ( plenty of depth but sealed to car and hard to remove)
Open to suggestions and will let them break in while i give it some thought. Already night and day from the Focals in the doors.

Here is free air. 60 ohm impedance and phase shift at ~35hz fs.
View attachment 17298

Here is with membrane I can fit. ~10ohm impedance and better phase response.
View attachment 17299

Will work on waveguides while I fine tune AP setup.
 
So are the membranes to cover the 6.5's like grilles?
I ask simply because I WISH I could do drivers like that - we get so much snow and slop in the winter, wet feet and all that - and even if not I'm sure my fiancee would put her heel right through.

But with membranes covering them - that would solve that.
 
No, its a 2 chamber aperiodic enclosure. The kick panels are small sealed enclosures. They are connected to the sill panel of the chassis which acts as a larger enclosure. The "membrane" is the material that meters the amount of air that passes between the front (small) and rear (large) enclosures. This damping lowers the Q of the small enclosure and reduces the impedance peak at Fs. I use a DATS V3 to tune the amount of material needed and am using Rockwool and fiberglass insulation here.
These drivers added midrange detail and improved midbass response. A friend and former IASCA expert WC listened to the car with the Focal K2P in the doors and said the everything sounded great except for the missing midbass. Loved the sound from 500 up and the tweeters did really stand out. Now that midbass is is much tighter and articulate without any tuning adjustment and the mids/tweeters blend together.
Making some different and more permanent tweeter mounts and will hopefully be ready to dig into tuning soon. Then i'll get some people in for some listening/ critiques. Wanted yo get to NC to the SQ event for that reason. Haven't seen Keith in 17 years. I highly recommend these drivers but as always implementation and tuning are the key. They aren't going to be ideal dropped in a door.
 
Started on the pillars. Since the waveguide / tweeter combo will weigh 8-10lbs i decided to give them a solid base on the dash and mount to the car rather than the pillar trim. The airbags added some challenges, i can't go above a certain point and have to make sure the trim will break away and the tether will function as intended.
Plaster mold so i didn't have to resin in the car, set a mounting ring at the desired angle and stretch cloth to glass over.
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Through the mounting hole you can see the dog light bracket. I used that to determine the angle i wanted to mount the drivers on. That will be removed when the brackets are installed to secure the pillars.
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I have mockups of the waveguides printed and attached some wood to include tweeter dimensions to ensure fitment.
View attachment 17373

I'm debating how to finish them. Do i go with the brig beige of the pillar trim, get off the dash or good black to match the dash trim panels?
 
Impossible Bill said:
No, its a 2 chamber aperiodic enclosure. The kick panels are small sealed enclosures. They are connected to the sill panel of the chassis which acts as a larger enclosure. The "membrane" is the material that meters the amount of air that passes between the front (small) and rear (large) enclosures. This damping lowers the Q of the small enclosure and reduces the impedance peak at Fs. I use a DATS V3 to tune the amount of material needed and am using Rockwool and fiberglass insulation here.
Click to expand...

Right - and you can 'squish' fiberglass or Rockwool or similar between metal mesh and front-mount it.

That was the basis for Richard Clark's legendary Grand National, and I even think it was SpeakerWorks who sold USD front mount kits that looked like opaque speaker grilles. I don't believe those were tunable, but they did come with some passive filter/compensation box... I don't recall specifically.

I was just assuming that was the application here. Pretty interesting regardless!

You may be thinking of other benefits - it just popped into my head as a solution to the kick risk. I don't think anyone dings for those kind of ergonomic limits these days in competition, and it does look cool regardless.
 
I used oval trailer light housings and seals to make it. They fit in the sill and have enough surface area.
I wanted to mount Purifi speakers in the car without the concerns of environmental damage from door mounting or sacrificing SQ.
They seemed to match my tweeters well and give me more flexibility.
As far as design intent, I had a client ask why his system sounded so different with the windows down and could i fix that.

I started thinking about it and decided to build a system with On and off axis response as similar as possible. I have a lot of room to play with the xover point / type/ slope and have a few biquads ready to test. The tweeters seem pretty happy at 1300Hz Bessel without a baffle.
The waveguides hopefully show up soon, the university is doing a presentation using them. They should really smooth of axis and compliment the. T34B and blend with the mid.
 
Impossible Bill said:
I have mockups of the waveguides printed and attached some wood to include tweeter dimensions to ensure fitment.
View attachment 17373

I'm debating how to finish them. Do i go with the brig beige of the pillar trim, get off the dash or good black to match the dash trim panels?
Click to expand...
Personally, I think matching the dark grey/matte black that matches the dash and I'll make my amateur lawyer case:

It'll minimize them visually, and blend them with the dash, which might be nicer when actually driving the car - but also even when purely listening, you want those psychoacoustic cues minimized.

On the other hand - is the panel they are actually mounted on grey/black? Or is the sill beige? "Whatever blends best" definitely should be the case, in my opinion anyway.
In fact, on the other, other hand - if you are doing work and need to finish them anyway - maybe the sills also could become black?


...we did plenty of builds through the 90s and 00s where "make it pop! Stand out! Show car!" was the vibe - fiberglass volcanoes, neon, motorization and all that... I personally think that's cool too, it just seems less popular these days - and worth noting that died with the '07/'08 recession, when flaunting bling became tasteless in the face of plight.
And as we head into a recession, I'm thinking milder is the safer option.

Food for thought, anyway. Honestly either is probably fine - both options take the "integration concept" road. :cool:

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Im thinking dash color is the way to go now that i can properly fit them in place. I think I'm going to paint the upper breakaway portion dark too to make them even less obvious. It's a good starting point and i can always refinish them later.
Thanks for the input!
 
The pillar trim pieces are done.
View attachment 17424

Taking a trip to NC this weekend and have a few xover filters ready to test out. Hopefully final WG will arrive soon and i can button up the final details and get into tuning. It sound pretty good flat which makes me happy and came in under budget which makesthe wife happier.
 
Impossible Bill said:
The pillar trim pieces are done.
View attachment 17424

Taking a trip to NC this weekend and have a few xover filters ready to test out. Hopefully final WG will arrive soon and i can button up the final details and get into tuning. It sound pretty good flat which makes me happy and came in under budget which makesthe wife happier.
Click to expand...

Where at in NC? I'm very eastern if you'll be around there.
 
Made some good tuning progress. Three were things I liked about each xover type which led me to try something different. I kept that one the entire ride home and think I have the crossovers I'll use when I really get into tuning this install.
 
I always wondered - since the HLCD years - if it might be possible to cut the back corners out of the dash top (and in most cars a bit of the A pillar I imagine, to squish it flat at least up to where the airbags start - and basically design an HLCD horn that starts way below, and curves in a way that hands off to the dash top and windshield to make for a HUGE HCLD.

I feel like you kinda have done what I always wondered about... Just wouldn't extend as low!

How is the imaging?

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