My door speaker install and the rest someday.

[snoopy]

Quote:

Originally posted by DaveNagy

The MINI H/K system also uses "digital" amps, correct?

-Dave

I think you will find the audio amp part of the Amp (if that makes sense) is a class A/B.

The digital reference comes in with the use of a DSP. i.e. the analog audio comes in from head unit speaker outputs then is converted to digital via A/D. The digital music is then passed to the DSP chip to it thing (speed vol, music setting and driver focus). Now depend on how clever Mr H/k was we could do the crossovers for the speakers in the DSP or convert it back to analogue and then run it through the analog crossovers (but active). Lastly the audio is sent via the final audio amp then to the speakers.

[Bad Ess]

How long will the battery run your stereo with the engine off?

If 6x9's will produce 25 hz what is the advantage of a seperate sub?

(I know the drill but love the argument. I have a 1000 watt sub in my living room.)

[Bad Ess]

I found the quarter section of the rear speaker cavity to be open over the wheel well to the tail light section. MINI put a thin piece of foam in as an air dam. I think this speaker area should be solidly boxed in. I thought about one part foam in a plastic bag to fill the gaps but my experiment never cured. Perhaps stuffing some heavy chunks of foam in there would do it. I want to avoid the mess of strait one part foam i.e. Great Stuff.

Does any one know how critical the ridgity of the wall is? I know most speaker boxes are solid. Does a wall of foam mess it up? I could cut and fit some plywood and silicone it in.

Here is the MINI baffel. The next shot is the wheel well lookin back on the left side of the car. The bump is the fuel fill pipe cover etc. I shot this with a light in the tail light area.

[Bad Ess]

Looking into speaker area. Left side looking aft. This needs to be blocked off acoustically.

[DaveNagy]

Nice experimenting and photography. We'll have to chip in and buy you a flexible endoscope.

Perhaps a 2-part foam would cure better in a sealed bag? I've been looking at the foam that Tap Plastics sells. I have a store local to me, so I was able to play with a cured sample. The stuff is quite rigid when set up. (I was thinking of using the foam to created a "form" for a fiberglass enclosure that would fit down into the battery box.)

Man, the opportunities for amusing foam accidents are almost unlimited. Mix too much and it might expand to fill the entire MINI! Seems like you might want to do something like this:

- Place a bag in the area where you want the foam "bulkhead".
- Use some chunks of squeezable foam or something to contain the bag, fore and aft. Perhaps the stock "dam" can be used. Duct tape might also help.
- Locate someplace where you can pour the goop into the top of the bag, and make sure you're prepared to deal with the extra foam that will come squirting back out!
- Once the foam is set, you should be able to remove some of the bag and if necessary, carve the foam into its final configuration. (I'm sure it will have bulged in places.)
- You might want to "paint" some extra foam goo around the edges of the bulkhead, to make sure the foam is sealed to the metal. Maybe do some syringe work to fill gaps.

I don't know, but I suspect that six inches of this foam would be fine as part of an enclosure. It certainly won't be heavy like MDF, but if it's airtight it oughta give you some nice damping qualities. You'll probably want to put some acoustic stuffing in the chamber anyway.

Quote:

How long will the battery run your stereo with the engine off?

Not sure if this was directed at me and my tiny battery, but if it was: The small battery only has about one third the amp-hours of a standard batt. So, I'd only get about one third the time. (I figure I'll need to be careful about that sort of thing. The battery will be more than adequate to start and run the car, but I won't want to run a lot of accessories with the car shut off.) Another reason to go with super efficient amps...

-Dave

[Bad Ess]

Dave,

I was knocking you on the battery. I used to run down a group 24 in about 20 minutes with a system with only one extra amp. (I might have to change batteries to compensate for the extra 10 lbs of magnets.)

If one could stand the MINI on end I would consider using two part foam. It is very hard to deliver without gravity. BE CAREFUL with this stuff it can push panels out.

Do you think foam is stiff enough. I would definely damp it and fill the cavity with hollow fill fluff too.

I think this 6x9 location has potential. I will run two pair of wires in case I bi-amp or change brands later.

I can see the road noise will be reduced by the proposed treatment. That's a big plus.

I'm off the project for a few days..standby..happy and merry.

[Mardav]

Hey Dave,
Although I had my speakers professionaly installed, The 6.5 JLs fit perfectly with the stock grills and sound too awesome. There is a company that makes speaker adapters that will work. I think it is Metra or something similar, Circuit City carries the line and would know the correct name. Anyway, they make a 1" spacer I was going to use with the Infinity speakers I bought before I discovered JL Audio. No modifications are necessary.

[DaveNagy]

I definitely think that 2-part foam is stiff enough. It seemed significantly harder than styrofoam, although not much denser. I squeezed the softball-sized chunk that was in the store, and I couldn't compress it at all. It sounds "hard" (and kinda hollow) when you rap on it with your knuckles. Neat stuff, I thought.

I just thought of a another wacky way to form your enclosure(s). It's sort of the inverse of your foam-in-a-bag idea. Take something like a beachball, insert it (deflated) into the area behind the 6x9 cutout. Then inflate it to your desired enclosure volume. Then, block off the area well aft of the cutout, maybe using the supplied piece of foam you described earlier. Finally, pour the expanding foam stuff "around" the beachball-like object. After the foam hardens, remove the beachball and enjoy your organically shaped, acoustically neutral, hermetically sealed enclosure!

Finding the right object to "pour around" would be the tricky part. That, and getting the foam to completely fill all voids without busting out (or into) anywhere you don't want it to. I think you'd need to pour from the very top, (that gravity thing you mentioned) and also allow any excess foam to escape the top in a controlled manner. I imagine you'd want to drill a "fill" hole up high on the panel. The foam I linked to can be poured in stages, I believe. I think as long as the area was not closed off while the foam was still expanding, the foam wouldn't exert much pressure on its surroundings. (But, I don't know for sure!)

A nice bonus is that your MINI will be unsinkable!

-Dave

[Bad Ess]

I made a wood pattern after the MINI foam part and cut it down and into two halfs to get this pattern. The panels are made from .050 aluminium. The grid is 1" squares. Make two identical and cut out for the fuel fill. It is a puzzle to get them in the hole. I glued them to the inboard lump with construction adhesive (Liquid nails). A day later I put in a support stick and filled the voids with one can of (16 oz) Minmal Expanding Great Stuff foam per side. I added an 18" piece of hose to the Great Stuff tube. There was no pushing power in the foam, I expected the panel to flex or deform if there was but it did not move. I have foam well over the wheel wells now as I observe from the tail light holes. Clean up is easy breaking away the extra foam. I am ready for Dynamat and some hollow fill stuffing. Should be awesome...

[Bad Ess]

more

[Bad Ess]

and

[Bad Ess]

Templates

[Bad Ess]

It should take less than 5 mins to re-assemble in the reverse order. Mind the hammer.


This by the way, is the proceedure for getting low level outputs from the stock head. Give GaryM credit for showing the way....his thread is very clear. (I can't figure how to bring it up here. Sorry.)

"I don't have parts left over so it must be right."

EDIT....THIS DID NOT WORK....GROUND LOOP HUM AND LOSS OF DYNAMICS.... the high level converters with the Blaupunkt PA 2100s work well with the stock head.

[Mini Cruiser]

all i can say is :eek

and that aint even a word

[Bad Ess]

Quote:

Originally posted by Mini Cruiser
all i can say is :eek

and that aint even a word

Well it's only money if you blow it...