Well I have actually had this install done for some time now, but just got my digital camera working again.... so I finally updated my web page.

Check it out....

CRX Audio System

This is a link directly to the audio system diagram.... the links to the left of it let you check out the install details.

The links near the top (just below all the Netfirms BS) will let you check out the rest of my site.... which is minimal at this moment.

Mike

What's the last (bottom) component in your dash? GPS?

It's a piggy back type engine managment device made by Apexi. It monitors the stock sensors (MAP, RPM, etc) and sends a modified MAP signal to the ECU. It is to compensate for engine modifcations (cams, etc).

Apexi S-AFC

This is handy, Im just about to attempt an install in my CRX and was thinking of putting the amp under the rear seat.
If you have any more pictures of this, Id love to see them!

You mentioned something about many different sub combo's you've had in the car, any pictures of these too?

Im planning on mounting mine similar to this site

There is a photo attached of one of the smaller boxes I had. This one was also fiberglass (100% in this case too), it was covered in vinyl.

The box shapre resulted in around 0.7 cubic feet if I recall correctly (but that is before taking into account the speaker displacement). It is similar in design to the one you linked, except that it doesn't have the extension out of the corner of the hatch (was trying to avoid the box taking up 'usable' space in the hatch).

In this photo, I had a Fosgate 10".. initially I wasn't too happy with the low end response. I wound up tweaking the speaker by mass loading the cone (glueing weights to the back side of the cone). This flattened out the response and the speaker/box system has a lower cutoff point... but of course the efficeincy went down by a similiar amount (the other trade off is shortened speaker suspension life and possible cone misalignment if too much weight is added and the speaker is mounted vetically... although I had no problems).

I later installed the illusion audio 10" in that same box and it was a little better. But with either of these, I never had enough output in the 20-30 Hz region (but it did still hit about 126 dB at about 40 Hz in IASCA competitions.... almost the same as my 12 hits at 30 Hz).

If you build yours like the one in the linked photo, you should have significantly more enclosure volume... more than enough for a reasonable 10 to be happy with.

The two 8's I had were in low profile box about 9" deep that followed the contour of the rear of the hatch (looked like 6" tall shelf sitting on the floor... it was wood, but still light enough to be reasonable to remove to access the spare).

OK you are my god
Thats EXACTLY what I was planning to do!

Any more pics you have of that would be more than welcome...

Im planning to run one of these on either side of the boot space and box in the space behind the rear speakers too.
Maybe just moving your attached box a little further into the boot space so that the side plastics in the boot are flush. If I can find second hand plastics, they'll probably be removed altogether and the boot padded out more, as the ABS box gets in the way.

Im looking at Pioneer TS-E1777's in the rear (fill), Infinity components 505cs up front, and infinity RA6006 amp 4x 50W RMS and 2x75W RMS to drive the 2 Alpine SWS-1040 10inch subs.
The jury is out on the subs as I am torn between these and dual voice cone drivers for 2ohm ability, or twin 8ohms and bridging the amp.

APEXi comes later

Were you running your current amp through that attached sub setup?
Any ideas on the transfer function of the rex?

Ooops.. forgot to answer your first question regarding the amp under the rear seat.... I've never tried that in my CRX, but I had an 88 Civic before this car, and the only thing I ever tried to fit under any of the seats was an Audio Control EQL.

Initially, it was mounted under the front seat.... just barely fit after reshaping the lower seat pan slightly for more clearance. In my CRX, I think there is a little less clearance under the front seats..... but might be possible. An amp would be another story (unless it is one of those low profile amps... like the older Pioneer 4 channel ones, forgot the model, but the foot print was similar, but smaller than, an EQL and the heat sink was slightly convex, with the tallest point in the center being about the height of an EQL, maybe slightly less).

I also mounted the same EQL under the rear seat.... Like the CRX, the seat foam sits directly on the car chassis.... so I trimmed out a rectangular piece of the foam to match the shape of the audio control.... a panel on top of the audio control would protect it. That worked... but an amp might overheat since there is really no ventilation in that type of install. But now that I think of it, I believe the lower rear seat foam on the CRX is much thinner on the CRX, so this might not work out anyway.

I may have a few more photos I can dig up on the original amp rack/rear seat construction from my IASCA 2000 log book (it was originally built for three RF 200a4 amps... only recently, I swappd in the Xtant and made a new trim panel). If I find any.... I put them on another page on my site and post a link here.

I was not running the Xtant back then... I put that in this summer (I have had the spare tire sub box about 1.5 years now). The link below shows what I did have back then (from my IASCA 99/00 log book).

Previous System

I tried to attach it... but I think it is too large (so the attachement link fails... don't know how to 'undo' an attachment to a post).

Going by the amp manufacturer specs, I had similar amounts of power going to the 10s I had in the past and 12 I have now... but it is hard to judge by manufacturer ratings.

I don't have any specific info on the CRX transfer function, but it does seem to yeild about 2-3 dB more sub SPL than the loudspeaker modeling programs predict using the 'typical car transfer function'. I have found that with a sub crossover point in the realm of 80 Hz usually works well. A little higher crossover point on the front woofer crossover point (90-100 Hz) seemed to helped flatten response in the crossover region. I have been able to get pretty good IASCA RTA scores in the past only using the amp gain controls and crossover points (which is why I no longer have the EQL). Usually, the anomlies I had were in the 1-3 kHz region.... probably an ugly combination of interior reflections, the physical separation between my mids/tweets, and the off axis response of the woofer. What I mean by the latter issue is that the woofer was crossed over at a relatively high 3 kHz (high for a 6.5" woofer that you are way off axis from, on the driver side anyway) and the tweeter was also crossed over at 3 kHz (kind of low for a small tweeter). Raising the crossover frequency had a pronounced impact on the perceived sound stage (for the worse) and made the RTA response worse (the region where these anomalies existed grew wider). I eventually wound up using a low 2 kHz crossover point (4th order) via the DEX-P1R which yeilded the best results (the tweeters had a fairly low resonant frequency).

I have not RTAed my car since I put in the 3 way components in the kickpanels/doors, but I hoping even this will be better now (If IASCA ever has a show in SoCal again, I'll find out .

Anyway... with 10's on both sides, you should have some serious bass. I haven't dealt with Alpine subs... so I can't say too much about how they will sound in that size of an enclosure, etc. I have a friend with a CRX who built an enclosure similar to mine and used an Alpine sub. He was happy with the results, but I haven't seen him in person since and never had a chance to listen to it.

The Infinity components and amp should work out pretty good. Are you mounting the highs in the upper doors or maybe in the inner mirror trim panel? I have done the latter, and that worked out well (but tweeters need to be smalll in diameter if you still want to use the manual mirror adjustment - if you have manual mirrors, that is).

ABS box? I didn't have to deal with that as no US market CRXes got ABS..... but I have seen photos of that box you are talking about.

Well, you sure gave me a lot to think about!

I was planning on having the tweets firing toward the rear view mirror, mounted on top of the wing mirror blank plates. Hopefully, smooth this over and make it look stock eventually.

Looking at your install photos, I was just wondering why you have two front window demist buttons on your heater control. In the UK, the one on the far right is usually labelled A/C for Air Con, if fitted.

ABS is handy (phew) just wish that they had found a different place to stick the box, its a real pain where it is...

Here in the US, the button on the right is usually for the same thing - the AC. But, I don't have A/C.

I was just trying to clean up the dash area some.... I just had a switch blank where the AC button should be in my climate control panel... so I got an AC switch, and modified it a little so that it could replace the rear defroster switch in the dash. The switch in the lower instrument hood on the '91 (maybe other years too) is combined with the dash brightness controller. I didn't really need that either (Indiglo gauges, etc), so I removed the switch assembly and made a new insert that has only the Indiglo gauge controller.