[OhSix]

Started out with the Sony XAV-65 and two pair of cheap Kenwood separates under the delusion it would be good enough. PFFFT. The Sony's quirky U.I., lousy iPod control, lack of software based frequency and active crossover controls, and a cheap class D amp driving the barely sufficient Kenwoods proved to be downright unsatisfying, even annoying.

So, gathering replacement gear began. Planning of each upgrade is intended to give time to assess the affect and value of incremental improvements. First to go was the Sony, replaced with a much improved Pioneer AVH-X3700BHS.

The Pioneer is light-years ahead of the Sony in software maturity and usability. Everything from backlight color control, superior iPod interface, very flexible frequency and crossover control to a very intuitive U.I., the Pioneer was like moving from a clunky first generation off brand mp3 player to IOS6.

Next to go were the Kenwood dome tweets in the factory location, replaced with AMT Mini's from Parts Express. Being a big fan of the original Heil Air Motion Transformer, the reintroduction of Dr. Heil's design coincided with the upgrade project, so it was a no brainer for me. After breaking out the calipers, it looked like they would shoe into the factory grills perfectly, and they did.



At first, the Minis were crossed first order way up around 10Khz using the Jantzen Mylar caps in the image, mostly because I was paranoid about operating them down to the upper limits of the Kenwood mid/woofers. While the high frequencies shimmered, there was way too wide a gap. The caps were by passed (for now) in favor of using a third order 4.5Khz two way xover from the box of tricks lingering in the garage. That changed everything. Now we are getting somewhere.

There are many folk who shun the idea of high frequencies reflecting off the windshield and the existence of full range rear channels. All I can say about that is some people like catsup on eggs, some don't. There are plenty of opinions about sound staging and such, which are all valid, however after spending several years in professional audio, I can only state my opinion. An automobile does not lend itself easily to focused sound. We can optimize the best we can but there are also genuine benefits to experimenting with reflections and phase coherence (or incoherence) which can reap huge rewards in a pleasing listening experience.

For the moment, I'm very pleased with the sonic improvements these two changes brought about.

Next up: DC wiring and amplifiers. The box of tricks in the garage had a near pristine old school Zapco 151 with the 200 remote power supply. This is the second generation version class A/B amp using a separate power supply/filter and amplifier chassis. She now lives behind the drivers side back seat, driving the front channel quite nicely. She's been running for a while and doesn't seem to mind being backed up to the CCF liner installed on the back wall. Using a laser temp gauge, the hottest measured temp at the heat sinks is 105 so I'm good with that.

There's a project underway for a subwoofer install that should be pretty unusual for the Ridgeline. Pictures of that will have to wait until more progress is made. For now, lets just say available space in the bed will be reduced a bit. In the meantime, I opted to run one Zapco STX-2 mono connected to the stock (GASP) woofer. It will be interesting to see how much that thing will take. One thing is sure, it does an OK job of getting down below the 4-6 3/4 Kenwoods, by a big margin.

 

[OhSix]

The St-X's are stacked one on top of the other with enough air space to promote some cooling. The front Kenwoods will be replaced with Silver Flute 6.5". Another project underway is the addition of aluminum cone Fountek 3.5" in an interesting custom housing pointed to the top of the center post between the doors on the opposite side. Another ribbon tweet of a different design will be going in the door sail, which should make for a fairly decent time aligned 3 way system in the doors. Silver Flutes are fairly flat out to 5Khz, but they be limited to 1.5Khz second order with the Fountek's operating 1.5K third order up to 5Khz where the new ribbons will take over. While the doors are apart, generous application of de-flex too.

Before any of the changes were made, I've been creating an acoustic signature for the vehicle in stock form, just to understand the noise characteristics before and after the changes. I'm mostly interested in the noise floor, not so much the systems performance. The more noise eliminated, the more the system can shine.

Before installing the new Zapco(s), they were taken apart to check out the construction and design. Pretty nice for such a reasonably priced amp. I hooked them up to my desk system and let them run for several days just for fun.


More as things progress.

 

[coolbob]

Refreshing take on upgrading the sound in a Ridgeline.

"lets just say available space in the bed will be reduced a bit"
Hmmm, sub box in front the bed ported into the cab?

I saw a Saab convertible at the Car Audio Nationals in Dallas (1988 I think), the interior looked totally stock but the thing had mids and tweeters hidden all over the place and it was thumping like mad. The trunk was open and at first glance, it looked stock too. They built a sub box in the trunk, under the well for the convertible top, inside the box were four long-throw 10" drivers in a bandpass enclosure. A pair of 4" tubes exited the box, went under the rear seat and emerged between the floor and bottom seat cushion. Until you knew what to look for, it looked stock.

I've wondered if it would be possible to use the 'trunk' as a sub enclosure and port the sound into the cab.

Anyway, please keep the photos coming, I can't wait to see what's next.

 

[beatle]

Looks great so far! I'm interested to see what the rest of the system looks like.

 

[OhSix]

Refreshing take on upgrading the sound in a Ridgeline.

"lets just say available space in the bed will be reduced a bit"
Hmmm, sub box in front the bed ported into the cab?

I saw a Saab convertible at the Car Audio Nationals in Dallas (1988 I think), the interior looked totally stock but the thing had mids and tweeters hidden all over the place and it was thumping like mad. The trunk was open and at first glance, it looked stock too. They built a sub box in the trunk, under the well for the convertible top, inside the box were four long-throw 10" drivers in a bandpass enclosure. A pair of 4" tubes exited the box, went under the rear seat and emerged between the floor and bottom seat cushion. Until you knew what to look for, it looked stock.

I've wondered if it would be possible to use the 'trunk' as a sub enclosure and port the sound into the cab.

Anyway, please keep the photos coming, I can't wait to see what's next.

That description of that Saab sounds cool. I've always admired invisible systems with impressive sound. It ain't easy but it sure is fun to pull off. *Back in the day* at C.E.S., a fabrication shop demo'd the "1KW VW". At the time, one thousand mobile watts was unheard of. If I recall correctly that Bug used a bunch of Precision Power amps, the space that was the back seat was occupied with a ridiculous amount of 10" subs. It had a wired remote because there was no such thing as wireless controls then. They loaded a cassette (HA!!), closed the doors with no one sitting inside and turned it up until the windshield literally blew out. That was part of the plan because there was a rack of new windshields in the support truck. Even though they cheated by powering the system with a monstrous external DC inverter (there isn't enough space inside a Bug for batteries) it was the talk of the show. Never got to sit and listen but I'm guessing SPL was their only goal.

The idea of using the trunk as a band pass sub cavity was toyed with but it intrudes on the design criteria of giving up the least amount of useable space. Plus, it would be a mother effer to engineer & route ports suitable for passing air over distance to the cab. If this system turns out somewhere close to the picture in my head, it will be nearly invisible, take up about 4" of unused space in the bed and sound pretty good.

BTW: I've read comments about the factory sub and they definitely influenced my opinion about a system system capable of the punchy attack and accuracy required to reproduce the lowest octave. Last night during drive time, Porcupine Tree "Russia on Ice" came around on iTunes. The end of that tune has a synthesized bass line that would stretch any sub. I pulled over to back up the track and re-listen a couple times just to make sure what was heard was actually there. No matter what I did, I could not get the factory sub to audibly distort. That's with one Zapco running mono rated ~160w into 4ohm. While it didn't part my hair, it was much better than expected from a factory sub. Having heard Bazooka's and other single box solutions, I would suggest adding a decent small footprint amp to a mildly upgraded system utilizing the factory sub is a viable solution for those who desire to keep under seat storage. Mixed with a good mid/woof/mid range/high freq speaker system it would be hard to beat by any appreciable measure. The biggest risk might be durability from driving the factory sub hard over time.

This board has made a huge impact in my understanding of the Ridgeline. In fact, it convinced me to purchase one to replace the Dodge Ram that was totaled about this time last year. After owning various vehicles and working on hundreds of vehicles in an earlier career, this one is a true stand out, it just may be the most pleasurable vehicle I've ever worked on. It amazes me Honda can produce this awesome truck and sell it so "cheap". My 06 drives as well as any new vehicle, is quiet, comfortable and a stays stuck to the road no matter what the terrain is. My only beef is ~16MPG. I really appreciate everyone who posts here. Great information that has made a huge impact on enjoying the Rodgeline. Thanks to everyone who participates!

 

[coolbob]

Good to know that the factory sub can take more power. I'm not 'into' car audio enough anymore to build a box, but adding a good quality, small amp should be an easy task.

I highly recommend getting a copy of this CD if you can find one. This was the test disk everyone was using at the competition. It has superb recordings that really push the musicality of a system, not just bass and SPL. It also has a listener's guide that tells you what to listen for for each track. I picked up a copy at the show and would not sell it for any price.

Official Alpine Reference Disc Car Audio Nationals II
https://www.murfie.com/albums/various-artists-official-alpine-reference-disc-car-audio-nationals-ii

One last tale from the show.

I was visiting a friend in Plano and we were driving around down-town Dallas looking for the competition. We knew it was held at a convention center, but not much else. Eventually we heard very, very low bass notes being delivered with surprising clarity. (Keep in mind that we had heard a Cadillac Hearse with a 30" sub the day before, and this was better.) We rolled down the windows and followed the sound which eventually let to a small, side entrance door to the convention center, 2-blocks away and inside was a Toyota extended-cab pickup with 4 15" subs which was competing in the Under-100-watt class!

 

[OhSix]

Update:

These are the front drivers destined for the front doors. Hopefully there will be time this weekend to get into that project. The Silver Flutes are simply ridiculous value for the $, at least in construction and cosmetics. Cast frame, butyl surround and a suspension for good X_MAX should work out OK in the free space of a truck door. The curvy PVC pipe is a proto type for mounting the Fountek's. Had a lotta fun creating the template conforming to the place where they'll end up. These beefy little 3" look sweet. They are billed as full range handling 15W for desk top systems and such. Hobbyists sometimes build line arrays with these and rave about the results. I'm betting they'll do fine as a dedicated midrange between ~ 1K and 4.5K. And I have high hopes for those little planar tweeters headed for the door sail panels. They will be installed in a way that should make them almost invisible.

Here's my buddy Jake of the Flying Dutchman Company fabricating what will be a wall of the subwoofer cabinet.

Right now the rear seat is out, which makes driving sound like the back window is open. It also makes tweaks here and there super easy. With the orientation of heat sinks on the amps, getting to know how they behave has been reassuring as well.
This morning before drive time, I took their temp.

45 minutes later, after playing the system mercilessly, I took their temp again.

Eventually, the STXs will be driven harder than the single unit driving the factory sub, and when both amps are running, I expect the temp to increase quite a bit. Cross that bridge later. The 151 seems to be plenty comfy for now but that might change when the interior is fully installed and air flow changes.

 

[OhSix]

Speaking of merciless, this is SPL sitting still in a quiet area, so the pressure is coming from the system as it sits today. No outside noises are contributing to this reading. Since I'm not concerned about breaking speakers, I pushed it to the point where I didn't want it any louder:

Here's a (kind of) profile of the factory sub. This graph was captured using a calibrated microphone placed approx. 18" from the sub face during a random music track - not a test tone - which would be much more meaningful for measurement purposes. There could be an entire thread about proper acoustic measurements, but all I'm trying to do is get familiar with what the system sounds like and record something to compare it with later when things start taking shape. The spread in the RTA graph was randomly limited to freqs below 300Hz. RTA full spread goes out to ultrasonic but I saw no need to pollute this quick and dirty measurement with stuff in the upper bands. While the factory sub is certainly not audiophile quality, it is respectable within it's limits. If filling in the missing bottom of full range speakers is what you are seeking, and you don't want to spend a bunch of bucks or lose storage space, just stick a small amp on the factory sub. You'll be surprised at how much it adds. I can't seem to blow this thing up even though I've tried. And I've yet to hearing any cone break up or the BRAAAAAT associated with reaching physical travel limits of the speaker itself. Perhaps putting in the back seat will change all that but for right now, it is remarkable what that plastic box will do.

Note the levels, output to the sub is attenuated in order to get a bottom without tubbiness. After playing with things, this sounds OK to me.

Pioneer XOver adjustment options. I love this U.I.

 

[OhSix]

Totaling a Dodge Ram caused me to seriously assess why and how I use a truck. While the 6 foot bed came in handy on occasion, it's maximum capacity went mostly unused. The cab was roomy but the truck was large and often challenging to park. When it wasn't loaded, it was unpredictable on wet or icy roads and I would never come close to needing its tow capacity. Considering the superior creature features of the Ridgeline, the shorter bed was an OK trade off for my use. After driving it for several months hauling junk around, it occurred to me the recessed space below the rear cab window was nearly useless except for stuff that happened to fit under the top lip of the front bed panel. It looked like a flat panel would be a way to gain space for a sub woofer without sacrificing too much bed space. So I'm giving that a shot. If measurement's and estimates hold true, the resulting cavity will provide ~.36 cu ft. of sealed air space. The goal is to create an opening into the interior where it will join with another cabinet - the total volume should be somewhere close to 1 cu ft. depending on final construction. Pending final driver selection and port dimensions, tuning should yield >30Hz which, in such a small space will be more than adequate for my tastes. I have a specific idea in mind to allow forward air displaced by the woofer cone to flow directly into the listening space, but there are a couple of things in the way that I haven't been able to think around, so we'll see what happens when the time comes to fabricate interior parts. If those issues can't be resolved, this is going to be an expensive experiment.

Here's how the flat bed wall is panning out.

 

[OhSix]

The box walls will be made of square aluminum tube, something like this.

Nutserts for all attach points, gasketed with 1/4" neoprene. The cab wall and inside of the new aluminum panel to be treated with Cascade VB2.

Driving around without the inside rear finish panel and seat installed is driving me nuts. Keep looking back to see which window is open as air rushes out the vent ports.

 

[dtexan]

Oh wow taking this to the next level. Great progress and build!

 

[coolbob]

Bumping the back wall out a few inches is definitely thinking outside the box. Fantastic metal work by the way. Wish I lived closer so I could watch this build in person and experience the end result!

 

[cccbock]

Oh wow taking this to the next level. Great progress and build!

What he said^^^^ Wow. Nice

 

[OhSix]

Bob, beatle, tex and bock, thank for the comments. Your feedback is very encouraging.

There's only one thing worse than tearing into a project only to run out of day light & hours the next day to complete one phase of a project and that's when life throws a curve ball and interrupts the whole thing. Looks like minimal progress this weekend - PHOOEY.

 

[ebrit003]

Nice looking bed panel! Strong work; keep us updated.

 

[laserguy]

Very nice class AB amps for smooth clean sound, top quality amps.


Question, since it seems that you will have a 3 way front and subs system, will you be running the 3" drivers in parallel with the tweeters since you only have 6 channels available and not 8?, unless you add a DSP. Also the silver flutes play clean and well up to 3Khz, I assume you will LP them at 1Khz or 2Khz since based on the info I read, the 3" drivers I assume will play from 1Khz or 2Khz up to the next set of frequencies where the tweeters will play.

The only way I can think you can do this 3 way front active system and sub with a 4 channel amp and a mono amp and without a stand alone DSP box, is using the Pioneer's 6 channels, the pioneer driving the tweeters, channels 3,4, for mids, 5 and 6 for mid bass using the 4 channel amp, hopping the Pioneer's 5th and 6th ch crossovers allows crossing up to 1-2Khz for channels 5th and 6th or use the amp's HP LP, then use the pre amp outputs from the 4th ch amp and connect those to the mono amp to have the extra 2 ch missing for sub channels.

Sorry for the Complex long post and many questions, just trying to figure out what your plan is and if you wish not to share it now or later I understand.


Great job on the bed wall , I look forward to see your sub box and curious about what sub or subs you plan to use.

 

[OhSix]

Very nice class AB amps for smooth clean sound, top quality amps.


Question, since it seems that you will have a 3 way front and subs system, will you be running the 3" drivers in parallel with the tweeters since you only have 6 channels available and not 8?, unless you add a DSP. Also the silver flutes play clean and well up to 3Khz, I assume you will LP them at 1Khz or 2Khz since based on the info I read, the 3" drivers I assume will play from 1Khz or 2Khz up to the next set of frequencies where the tweeters will play.

The only way I can think you can do this 3 way front active system and sub with a 4 channel amp and a mono amp and without a stand alone DSP box, is using the Pioneer's 6 channels, the pioneer driving the tweeters, channels 3,4, for mids, 5 and 6 for mid bass using the 4 channel amp, hopping the Pioneer's 5th and 6th ch crossovers allows crossing up to 1-2Khz for channels 5th and 6th or use the amp's HP LP, then use the pre amp outputs from the 4th ch amp and connect those to the mono amp to have the extra 2 ch missing for sub channels.

Sorry for the Complex long post and many questions, just trying to figure out what your plan is and if you wish not to share it now or later I understand.


Great job on the bed wall , I look forward to see your sub box and curious about what sub or subs you plan to use.

Laserguy, thanks for the feedback. Complexity abounds with this build, your questions are great food for thought.

Budget being what it is, literal bang for the $ is the rule of the day, as you can see by loud speaker selections. I'm trying like hell to avoid the snow ball that is the wicked quest for sound. $ + challenge of routing cables through RL door jambs = reason to avoid the better option of full active. Although routing could be done with a little effort too. When I was in the biz, I had the opportunity to witness long term affects of drilling holes where water goes - even with grommets, bare metal left untreated is a bad idea and treatment can be sloppy ugly. With the 06 approaching the 100K mark, cashish will soon bleed into maintenance. Dang it.

Right now there's a pair Soundstream Exact 4.3 fourth order, 4.5Khz, 4ohm dividing networks stuffed in the air ducts behind the H.U. splitting the AMT's and Kenwoods. The AMT's are 8ohm but that doesn't change things much, they are sounding just this side of spectacular, reaching lower and achieving SPL I didn't expect. That ribbon-ish / electro static / planar like detail is right up the alley of my ears.

When the 4.3 xovers are moved to the doors, incoming full range will branch to a simple coil/cap for the Fountek's. I have several combinations to play with but expect 6bd roll off around 1K and 4K-ish should blend alright. I'm toying with the idea of running the 3" full out but might not like messing with the planars as a point source. The overlap with the upper end of the Silver Flutes and the lower end of the Founteks isn't too concerning because phase at those freqs are not critical - at least to my ear. But proof will be in the listening. If that doesn't work out, I'll just build a proper 3 way third order and call it even. With the Silver Flutes @ 4ohm, the Founteks @ 8ohm and the planars @ 6ohm, final impedance should be well within tolerance for the Zapco 151. And hopefully, power will be sufficient too.

On the low side, the Zapco STX are (going to be) running mono with the intention of using a single dual VC driver. After looking around, I'm really attracted to the RE line because they are so well engineered and constructed. But they seem to be watt hungry devils and I'm not confident 170 per coil will make it dance as well as it could with 800 or more. In retrospect, a class D Zapco may have been the better choice but oh well. I've heard many, many sub drivers in all kinds of enclosures and frankly, I'm not a fan of bigger is better. Moving a large surface area might bring efficiency and power handling but it also brings sluggishness. I prefer a faster bass as long as it's deep too. The best vehicle systems I can recall employed multiple 10's or 8's in pretty simple/well constructed ported enclosures. Compensating for smaller diameters using multiple light weight cones is very effective in the small space of a car. Since the enclosure for this system dictates the use of a single driver, as large as possible seems prudent, which if dimensions work out as expected means a 12". The final choice remains open until the enclosure reaches construction phase.

One more thing. The AMT's are so pleasing, I'm thinking of driving them with the Pioneer's internal amp crossed with the Jantzen caps in the O.P. image. If things get overly bright or stage confusing when added to the planar sail tweets, they can always be disconnected, or perhaps tamed with an l-pad if needed.

Any ideas on this jumbled mess of thoughts is most welcome.

 

[laserguy]

The way I see it, or if I get it right, you want to bridge the the 4 ch amp to get the most power, and have the midbass, mid and tweeter somehow all connected in parallel or series to get a correct load, while using caps to protect or limit the range of frequencies sent to a them?
Or use 2 ch for the mid bass and the other 2 ch for mids and tweeters?

I'm not skilled to determine the cap and coil values needed or create a passive crossover for such drivers, you most know what you are doing. You have an HU capable of active pre amplified frequency filtering that will offer clean sound and I simply would not deal with passives or caps if it was me.

I don't want to steer you away from your plans, I know sometimes you just have to try to see how it works and make changes or eliminate drivers if the result is not good or it can be better. I'm just sharing my thoughts, here, feel free to keep reading or ignore my suggestions. :act030:


A 3 way passive system will be very hard to tune specially if you have at least 2 drivers connected in parallel with different impedances and sensitivities and passive post amplified frequency filtering, not having an extra 2 channels to have full independent output level control to balance their sound. Tweeters and mids need to be next to each other, the closer the better as you probably already know.

Also if you keep the tweeters and mids near the dash or A pillar, you do not need extra new wire for extra speakers in the doors or window sail panel. Just run wire to the dash, some fabrication or special mounts will be needed for the pillars, but it may be way easier than drilling extra holes in the door for extra wires, or placing the caps coils or passive crossovers somewhere in the door panel if no extra wire is fished there for bi amping drivers. Many other places available to place caps coils or passive crossovers in the dash, behind glove box, kick panels and more.

Also A pillar mounting for mids and tweeters will give you a better stage besides making things easier, tweeters on axis or off axis will depend on on where they sound better without being harsh, you have a very powerful sound processor in the pioneer HU you can lower the output levels and EQ as needed.

I assume the 6.5" silver flutes will be driven alone with 2 channels, if not I recommend it since those are the ones you will time align and if they are connected in parallel or series with other drivers, you will not get the full potential from them.

If you are using the 8" silver flutes, I then would understand the need for 3" drivers.

Honestly the 6.5" flutes play good and flat up to 3200hz, even a gap between 3khz and 3.5khz is not significant . I checked your tweeters minimum response of 3500hz, and you can simply EQ that gap, or bring the HP on the tweeters to 3200hz, I'm sure it won't hurt them.

If you ran your tweeters, with the pioneer HU, you will need to set the HP at around 3200-3500hz, to off/ open or 20khz or higher LP if they can play higher, then the silver flutes with the other 2 channels from at 80 HP to 3000-3300hz LP wherever they sound better, no caps no coils no passives connected to the flutes.

For protection if it makes you feel better, a 12uf non polarized polypropylene Cap, the value based is aprox on half of the low crossover point of the tweeters, and it's 8 ohm impedance, connected in series . 11.5uf would be more accurate as you would find out if you double check it with an on line calculator, this is just to prevent DC voltage from the amp, even if the HU, looses power or the battery dies, the HU should no loose the tweeter crossing setting ever, but you will never know, if your amp pops or thumps when you switch your key, it can damage the tweeters.

And the cap will not interfere with the pioneer's digital crossover since it's frequency cut off will be below the pioneers crossover point.

This is how is done today, I'm sure I would not be the only person not in favor of a 3 way passive when you already have drivers that can play in that range and have the processing to do it.

If you want freq from 1k-4khz to be crisp and smooth, there are 2-3" wide band drivers that play up to 17-18khz if more detailed sound is expected with a raised in your face stage.

Again long post a lot to read and think about. :act063:

 

[OhSix]

Sorry, my usual blathering style failed to convey the intended design of the system.

The Zapco 151 (100W/ch @ 4ohm) will be HP controlled by the Pioneer internal filter, probably in the 80HZ range. It will drive the front 3-way channels consisting of Silver Flute 6.5" 4ohm woofers in the stock location, Fountek FE85 8ohm in an angled housing on the door - creating a sonic X pattern across the front seats, and Planar 6ohm tweeters in the sail panels slightly angled towards the opposite side seats. Final impedance with all drivers connected parallel should be somewhere above 5 ohm. I'm choosing passive crossovers for two reasons: 1) Avoid the cost of additional amps, DSP, cables, ETC. 2) Avoid the mess of routing 3 sets of wires thru the vehicle body and doors.

Pillar mounted pods are off the option list to avoid interfering with air bags deployment.

The Silver Flutes look to be responsive out to 5K, in fact there's a rise near their upper mechanical limit.


High end will be passively limited to 4.5K - Forth Order using the excellent Soundstream EXACT 4.3.

The Fountek's are super wide band, extending to 20K-ish.


But I favor the sound of planar (or ribbons or AMT hybrids) over cone or dome tweeters so the top will be limited with a coil and the bottom will be limited with a cap to increase power handling. And I have plenty of coil/caps of various values for playing with the width of that bandpass. The Fountek's are intended to warm up mid range and improve imaging by directing sound towards listening positions of front seat occupants. There will be overlap where the Silver Flutes operate up to 4.5K and Founteks down to ~1K but I'm counting on that for added warmth (as long as phase combinations don't get too weird).

The two Zapco ST-2X amps will run mono to create 170W X 2 for the sub which will be LP controlled by the Pioneer internal filter.

If I understand topology of the Pioneer, engaging the internal crossover affects both pre amp and amplified output, so IF the internal amp is used to drive the dash mounted AMT's, the cap that's already in place will pass 10K First Order with a 3db down point of 5K. That idea may or may not pan out after listening. I'm clinging to that because the AMTs sound so damned sweet right now, but the combo of the planars and AMTs may result in a confusing stage and too much hi frequency energy - but that could be tamed with an L-pad. Tuning is usually the most challenging part of final system configuration.

Additional edit: I have strong opinions about the quest for soundstage - at least as I interpret the way it is often used in discussions of mobile audio. I'll post something more about that later and try to keep text to minimum.

 

[IanRTL]

Yeah, I'm subscribing to this thread. The audio knowledge and conversation is simply astounding. Great work so far. Can't wait to see the end result!