I know we spoke privately, but I'll repeat some of it for everyone else's benefit...
King Nothing said:
...What size speakers are in the dash and what could fit up there in their place?
The left and right look like 3.75", but I bet you could get a 5.25" speaker on each side with a bit of trimming. You've got quite a bit of mounting depth on the sides, the diameter is what you're going to trim for. The center speaker is quite a bit smaller, it's 2.5", but I'm guessing that you could get a 3.5" or maybe one of the original side speakers in there. Diameter is not an issue in the center, as there's plenty of room to trim, but depth is significantly smaller in the center than it is on each side. If you're going to create a custom pod in the center, then I'm guessing you could go 5.25" here too.
One other point that I'll make about the dash locations in a Ram,
(And I know I'll probably get chastised by the same idiot who criticized the A-Pillar thread) is that speakers in these locations don’t lend themselves to good sound quality. (If that’s your goal) I put forth a significant effort in these locations, and musical instruments don’t sound believable with the acoustics of the Ram. If you don’t mind each musical instrument sounding like a recording of an instrument, instead of the actual instrument, than go for the dash locations.
King Nothing said:
...It seems that the door speakers are just for bass/midbass...
True. With the premium 7-speaker setup, these are only midbass drivers. (I'm answering for the 2007, but I’m guessing that the 2006 is the same)
King Nothing said:
...what are the crossover points and how is the filtering done (passive, outside the speaker or active in the amp)...
Tdog asked this same question earlier this month, and at first I thought, "Hmmm, Good question", because nobody knows what frequencies the Infinity "Premium" sound system is crossed over at...
But then I whipped out my RTA and actually measured it:
The dash drivers are rolling off (High Pass) about 400Hz.
The midbass drivers are rolling off (Low Pass) about 500Hz.
I do not know if the crossover is active or passive. Even if it’s built into the amplifier, it could be passive, because I don’t know if this amplifier is internally a 7-channel amplifier. It could actually be a 5-channel amp, with a passive crossover network added to the output section for the 7 sets of wires coming out of the molex plug… If you look at the gentle slope on the RTA screen, you’ll notice that the slope looks like 6db/octave, so I would guess that the crossover is actually passive. (Who would make a 6db/octave
active crossover? It’s less common these days.)
King Nothing said:
...I read somewhere that the front door speakers are 8 ohm. could a 4 ohm speaker be put in its place or would the amp not be able to handle that.
I’ve not read that they are 8-ohm, nor did I measure them when I had them out. (I’ve actually read posts telling me that they are 2-ohm, but it wasn't a reliable source) However, regardless, it is possible to put a 4-ohm speaker in there, and in fact I’m running mine this way currently. (for now)
King Nothing said:
...Finally, has anyone replaced the infinity speakers and what did you use?
Yes, I have replaced the dash speakers with “Point Source” style drivers.
I do not whore out brands, so I’ll keep that little tidbit to myself unless pressed on the subject, but I would suggest that you go and listen to several of the high-end brands out there, and decide for yourself what sounds good to you. Sound Quality is a very subjective thing, and speakers are the most important part of any audio system. Spend the majority of your money on the speakers themselves, and you won’t regret it later.
King Nothing said:
One more question. With the speakers not being full range, where would one tap in if he wanted to bypass the infinity amp and run his own? Could you tap in before the infinity with a line out converter?
Yes. You could try one of these:
LINK