Bill Ball

BTW, I agree with Tom about trying to mount some 6.5s low on the front of the doors. That is an ideal location acoustically. The sound level of the R & L speakers will be better matched for both you and the passenger when they are located low, rather than having one speaker almost next to your ear when they are mounted high.

Bill Ball

It's the tweeters in the rear that bother me more than the front ones. They shoot right at you. I found it hard to roll-off the harshness without loosing too much of the highs you want. Some silk-dome tweeters I bought separately plugged right into the MB crossover and sounded much better.

Kevin in Atlanta

IMHO: My 300E has the mid range woofer mounted at the driver's hips. I think that is a better placement. The high-range speakers are built into the dash and that arrangement is awesome.

RyanPerrella

ok hang in here with me guys. My ideas are all over the place, i feel like Danglerb here. But i assure you i am serious about this.

Considering how large the 5/6 channel amps are, and their cost, and mostly the fact that i would have to really change the layout of the rear hatch and loose a bunch of space, I think I will stick with the 2 amp setup now that i have a place to put them. The P200-2 at 200RMS should be perfect.

As for the 4ch amp, I really like the one Bill mentioned, and Dr. Bob is spot on with where to put it. Its really perfect, the CE panel cover. Its already wood, so its super easy to mount the amp, its large enough to fit the 15" x 10" amp and since its only 1" thick it wont take up noticeable footwell space. The best part is that the carpeting, both the floor mat and the overlay mats are loose there and you could cover the slight bulge that the amp would produce. So i wouldnt have to get anymore carpeting to cover a box or anything. Also being just 1.2" thick, i can put a rigid cover over it to vent the thing and so when someone puts their feet against the thing it wont be resting on the amp itself but a wooden or plexiglass cover sandwiching the amp to the fuse panel cover. This also prevents the carpet from laying on top of the amp which is horrible for heat dissipation.

That amp will then give me 75W RMS to all 4 channels and not invade on the limited interior space, this setup seems about perfect.

As of 7:36pm local time, thats what i am going with.

EDIT: 9:01 I am also looking at the Rockford Fosgate P400-4. These are rated at 50 x 4 RMS but put out closer to 75W, There are a number of these on Ebay so i am going to try my luck with one of these and see if i can pick one up cheaply. If i get this 2.25" tall amp, i think i will replace the 1/2" or so thick peice of wood covering the fuse panel with 2 thin sheets of plexi, or 1/4" wood, and sandwich the amp inbetween them. This will probably all total 3" which i can live with in the passanger footwell. Again this will be covered easily because of the loose floor mats which will lay the same way. I am hoping i can pick up one of the P400-4 amps up on ebay for around the same price as the Farenheit, so all things being equal, i prefer the rockford fosgate name. (I'm kind of turned off by reading specs on the Farenheit CLX730-4 as i see it dosent have mosfet wiring but i dont know if thats even an issue. Do i even worry about that. From the thread i know most things have MOSFET and now that i find something that dosent, i am a little hesitant.)

Note: as for cutting up holes in the door panels, that aint happening, i dont want to cut anything, there are already 6.5" holes in the b pillar and they look pretty good so the 6.5"'s will go there. And I dont think i need to add another pair of them, i think 10 speakers + sub is plenty, i dont need a bakers dozen.

Bill i am curious about your comment on the cheaper MB Quart 6.5"

I havent bought a PCE 216 yet, but if i did buy one, i would be purchasing it for just the 6.5" woofers, i would resell the tweeters and the crossovers. MB quart does have the "add a woofer" 6.5 in the refrence series. These are on Ebay for $50 plus shipping. You would honestly go with the refrence 6.5's to match the premium 4's even if money wasnt a concern?

I was going to just buy the refrence ones but wanted to match all the speakers.

Bill Ball

Ryan:

I've considered the passenger footwell over the CE panel. That could be made to work, although 3" inches with the Rockford is a lot of lost footspace. Also, doing it in a way that you can get to the CE panel without removing all the wiring connections to the amp would be a challenge. I couldn't get around that and decided against it, but I'm not the most creative guy on Earth.

Farenheit has NO NAME in the amp business, so I understand your change of heart. Frankly, unless an amp is really bad, it's not a big determinant of the sound, so I took a chance just to get a thin amp.

Regarding the MBQ low end speakers, my low end ones were real old DS-something or anothers. That's right, the discus series, but real old, long before MB got bought. And I was comparing them to the PCE 216 a couple of years ago. The old DS sounded better. They didn't look like they should, but they did. I never tried the reference ones or the Q series. Sorry if this screws up your plans. Probably go ahead and do what you were planning and see how it comes out.

I agree about holes in the doors. You'd have to have someone mold you some enclosures. Sterling redid the bottom portion of his doors to accomodate 6.5s, but that guy is an artist way beyond my capabilities. The result looks factory. Look at the 4th picture on this page. Also, he has a link there to how he did it.
http://www.928sg.com/interior.htm

Alan

Ryan,
If you install an amp on the panel cover - you do need to allow for airflow over the amp for cooling or you will have to derate its max power significantly. You can do this if you allow a small airspace and some flow from the top and bottom into the panel space - but that may mean another wooden cover in front of it to support the carpet... (or if it has fins maybe they have their own airspace)...

Just something else to think about..

Alan

RyanPerrella

I am thinking i would use plexiglass, or some similiar type of ABS or something, make a pair of plates that follow the sameshape as the wooden original. The Amp is listed as 2.25" high, the wooden board is what, .5" maybe? So if i can get the amp mounted on a real thin, but still rigid peice of plastic, or perhaps aluminum, and then put another peice on top of the amp with maybe 1/4-3/8 inch gap between what would then be the top of the kick panel, that should give me enough airspace or is that going to be pushing it? So if i follow this idea, i go from 0.5" to a 3.0" so its just 2.5". Again hardly anyone ever rides with me and if they did they could put the seat back, but this way would seem to me to have the cleanest look, its also completely reversable. Although Bill you do bring up a good point as to accessing the CE panel. Although this perticular amp has all its connections on one of the 4 sides, i could have all the wires route fron the bottom so removal should be fairly straightforward. If i need more airflow, i could potentially run a small PC fan, although i really wouldnt want to hear it, but then if i had the volume up i doubt i would notice it.

Also since the front speaker sets max out at 80 watts peak and the amp makes a real world 75 RMS, should i reduce the power to the fronts to balance out the rear's which also need to power a 6.5" if i have 75watts for a pair of 4's and tweeters and 75watts for the 3 way components in the rear, wont the front speakers overpower the rears? can i balance this on the amp and say put the front channels on power lever 6 or 7 and the rears on 10, can i adjust an amp that way? Ive never really played with one before, or is that where an equalizer comes it? I kinda thought those werent used anymore, but here we go adding something else to the mix.

RyanPerrella

just saw the 6.5"'s in sterlings car, those are nice, and they do look factory.

RyanPerrella

DAMN STEREO!

I am now catching myself searching Rennlist on how to upgrade the alternator! THIS NEVER ENDS! I never should have bought that stereo.

Bill Ball

This is handled in your headunit's balance and fade controls.

VehiGAZ

...as well as on the amp - the generally have a gain control to adjust the strength of the incoming signal.

Ryan, you will definitely need a fan for cooling that amp configuration (over the CE panel) - that's a powerful amp with very little air space around it, and it will all be under a mound of carpeting, too.

You should consider stepping down to a 50Wx4 amp - 75Wx4 power is for getting LOUD, so you will not be using even half of its capabilities, and you will have an easier time fitting a smaller amp and keeping it cooled.

Step away from the high-power alternators!! And keep clear of capacitors, too! You are not doing that kind of system... remember? Good sound but not too much volume!

RyanPerrella

Actually the amp is rated at 50x4

But with rockfordfosgate i guess they put out more then that. I hear your concerns about heat, but take a look at the p400-4. You will notice it has a very small heatsink exposed to the air. Its not very thick and runs along only one side of the amp. Of course there could be additional heat sinks inside the case that i havent seen as i havent pulled the cover off.

I did a test and put in 3 plus inches of books on top of the CE panel and placed the carpet over it. It looked good as i thought it should and would be completely hidden. The p400-4 is narrow enough that if the amp is mounted closer to the floor as opposed to closer to the dash, it dosent get in the way of the 90+ glove box. foot space is changed obviously, but i put the passanger seat back evenly to where i have the drivers seat and its still enough, you cant stretch out unless the seat goes all the way back.

As for grounding the amp, can i use one of the grounding locations that is used for the CE panel and its grounds as opposed to running a power and ground cable the length of the interior?

RyanPerrella

As for alternators, can i run these two amps on the standard 115 amp alternator?

I did find a rebuilder that has 130amp 928 alternators. Was this standard on the GTS?

I would love to buy Carl's alternator, but i am not going to pay $700 for one. I have already found a supplier for that specific ford alternator in a 200amp config.so if I really needed 200amps i could rig up one to work fairly easily, but if i were to replace it, the 130amp version maybe a better bet. (Ive never replaced the alternator on my car, one of the only things on the car thats not new, so it could be time)

But if i really dont need 200amps, or even 130 amps, then i wont go there. I may go with a rebuilt 130amp 928 unit later down the road if and when mine does fail. I found those for just over $100. Is the 115amp stock alternator enough to run the 2 amps?

Tom. M

I picked up a rebuilt 130amp one (GTS Style) on ebay..for like 100 and change...good deall..search around..they are there ..mine works fine...(once I fixed the excitation circuit )..
good luck..
Tom
89GT

VehiGAZ

Ryan, the OE alternator will be fine. You don't need to upgrade an alternator unless you are getting into ear-bleed power levels.

RF has a reputation for building amps that are more powerful than their specs because they used to be so solid you could drive them down to a 0.25 ohm load and get 4 times the power out of them. That was about 15-20 years ago, though, and about 10 years ago, I know that was no longer the case - they were no longer rated to operate below 1 or 2 ohm loads. I'm not sure what the story is with them today, so I'm not sure if that reputation is still justified, but if it says 50W rms, it's 50W rms - no company is going to underrate their amps into a different class and price point just for fun. If anything, they always overrate them.

Always remember that amp specs are a fertile field of lies - a manufacturer can say that their Series 10 X-Treme Kick-*** Rocker amp will crank out 100W max per channel, but that might be at a distortion level (% THD - total harmonic distortion) so high you wouldn't listen to it. That amp may only put out 50W peak at a 0.2% THD (acceptable level), which really translates into about 35W rms real power. Just in case anyone is interested, rms power is a better measure of the continuous power output potential of the amp, whereas max or peak power is what it's capable of only on transient power peaks. And it's all a sliding scale based on % THD.

Good luck navigating this morass of misinformation...