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OdieTRP
12-14-2004, 08:57 AM
I have a set of Type X comps for the front, was going to buy a set of coax's for the rear fill, but still have another set of Type X's I could use instead. They are going on the rear deck in 6x9 slots but I have an adapter plate that will let them fit easily. Would this be too "good" for the rear fill? They will be powered by a PA 75x4 amp so power is not an issue. Before you give opinions that you wouldn't use a rear stage, please keep in mind that it's not my car and rear speakers are a must. I'm also curious how much more difficult it would be to tune correctly. Thanks for all the knowledge.

OdieTRP
12-14-2004, 08:59 AM
One other thing too; I won't be adding a sub to the system until spring, just fyi.

fossil99ca
12-14-2004, 09:32 AM
I would consider bridging your amp to give you 150 x 2 (if possible) to the fronts and using the deck amp to power the rear fill. You can always fad out the rear to your liking or kill it altogether. This will make the car owner happy because they still have sound back there. 150 to the front gives you lots of head room and avoids clipping. If the speakers cannot handle 150, turn the gains down or the volume.

If you have speakers lying around, why not install them. Having tweeters in the rear pulls the sounds stage back which isn’t good IMO. But again you can always fad them out when you are in the car. Although the other person driving the car would probably never notice if the fronts sound good enough.

When you get your sub you can always un-bridge the fronts, and use two channels for a sub or get another amp for the sub.

Disclaimer: I do not know all the specs on your equipment so please check the owner’s manual to see if everything is do-able (i.e. bridging your amp, etc)

maylar
12-14-2004, 09:33 AM
Why is it a "must" to *** up the imaging?

Rear speakers - run em off the HU. Never amp them. Don't use components.
Unless the front stage is so weak that you have no choice, in which case the rears will be your primary speakers and nothing is "too good".

MetalMaxima
12-14-2004, 10:29 AM
Why is it a "must" to *** up the imaging?

Rear speakers - run em off the HU. Never amp them. Don't use components.
Unless the front stage is so weak that you have no choice, in which case the rears will be your primary speakers and nothing is "too good".

I am assuming that everyone downplays rear fill due to the poor imaging provided by OEM speaker locations. Would adding a quality rear fill have an increased effect if you could change the imaging?

I have a large rear backseat and am considering running a set of midbass or comps using a fiberglass panel down the middle of the rear seats OR mounting a set on top of the rear deck using fiberglass pods to point them out instead of up. Would this not create a noticable change in the rear fill? ...or is this just wishful thinking?

OdieTRP
12-14-2004, 10:34 AM
Why is it a "must" to *** up the imaging?

Because it's what she wants, plain and simple. She carries passengers and wants rear speakers. It is not up for debate! :smash: Were it my system there would be no rear stage.
I understand the theory that the best speakers should be up front for staging, imaging, etc. The Alpine Type X's are rated at 70 RMS (2003 models); bi-amping them would fry the tweet wouldn't it? Even bridging the amp would put at least 150 per ch to them which is way more than they're rated for. I got them new for $150/set and bought two sets. I am trying to prevent spending a lot money and could put the other set in the rear. Why should I spend even $50 for a set of Planet Audio coax's or $100 for Type S 6x9's that will sound like **** when I have a good set of speakers to put back there? It's one heck of a dilemma and paradox, can the rear speakers be too good? The HU is a 9830. If I do put coax's back there, can the 4 channels from the HU be bridged to two and run off the rear RCA's to get 36w per channel?

ANeonRider
12-14-2004, 10:38 AM
I am bi-amping my Type X comps, just keep the gain down on the tweets or use the attenuation circuitry on the crossover.

themainjam
12-14-2004, 10:48 AM
well i was running 100W to the type R 5.25 and they handled it just fine.....

i have another question though. in my 4 runner i have 6.5 up front which i am going to put some orion p6.2 and in the rear they have enough room for my 5.25 Type R... i was thinking of setting it up like this..

6.5.........6.5
.....S.....S
5.2.........5.2
.....S.....S

the "S" stand for the seats where people sit. so that would give good imaging and shouldnt interfere with the front because the seats will absorb most of it...

fossil99ca
12-14-2004, 11:03 AM
I don’t think you can bridge a HU because they are not 2 ohm stable. Don’t forget the amps in the HU are like the size of your thumb. Bridging your amp (I believe) should quadruple your power. Like my JBL amp is 40x4@4ohms, 80x4@2ohms and 160x2 bridged only at 4 ohms. At 2 ohms bridged it would be 320, not recommended. So you’re your HU would be 72 watts bridged, again not recommended.

Rear fill is not a paradox, its personal preference. Try it at 70x4, if you like it, keep it. You always have the fader. If not, just disconnect them.

Yes you are taking more of a risk with 150x2 for them blowing but less for clipping them. Depends how much you push your amp at 70 watts.

bri487
12-14-2004, 11:15 AM
ok, here it goes. "Front stage" comes fromt the fact that live music is played in front of you right? how the music was intended to hear is what audiophiles are constantly trying to reproduce. if you have rear fill it only takes away from your front stage. i hope that is helpful

OdieTRP
12-14-2004, 11:52 AM
Because it's what she wants, plain and simple. She carries passengers and wants rear speakers. It is not up for debate! :smash: Were it my system there would be no rear stage.
I understand the theory that the best speakers should be up front for staging, imaging, etc.

Why is it so **** difficult to get info without people trying to change the system? :verymad: READ THE POST! I don't care if you think just having a front stage is the best way to do it; for the last f'ing time I KNOW THAT! Now, this has been a great forum for me to learn and get info. But, to be blunt at the risk of being rude, your opinion on whether or not to have a rear stage is irrelevant, meaningless, a waste of time, useless and furthur more lacks common sense because you can't bother to think critically about the problem at hand! :furious: For those of you willing to help with the problem I can't thank you enough and will be more than happy to share any knowledge I have. For those who need to interject their front stage only opinion, stay the hell out!

themainjam
12-14-2004, 12:06 PM
ok i would try to put the comps in the door (if 4door)and face the tweeters back. but if you cant do this and are going to run them in the rear deck then a cheap set of coaxials might be a better choice then using the comps.

1. coaxials will be just as good if not better than comps(because comps are for imaging while coaxials play good from off camber surfaces.)
2. comps facing up and tweeters facing forwar will mess up the front stage...
3. you can run coaxials off Hu power without worrying about underpowering them....

themainjam
12-14-2004, 12:09 PM
P.S. hope i helped :)

OdieTRP
12-14-2004, 12:18 PM
P.S. hope i helped :)


That is very helpful, thank you! I have two sets of comps but will probably now use only the one in this car. Anyone have a set of decent coax's (6x9 or 6.5) for cheap?

nosaj070
12-14-2004, 12:19 PM
I have to agree with the topic starter, this did go way off. Look, I see absolutely no problem making a baffle and sticking the tweet and the midrange next to eachother on it. Obviously keep the gain a bit lower than the front so its not completely pulling the stage back. Also it can be turned down quite low, because all the passengers heads are going to be less than a foot from the speaker. I say do it :)

maylar
12-14-2004, 01:35 PM
I have a set of Type X comps for the front, was going to buy a set of coax's for the rear fill, but still have another set of Type X's I could use instead. They are going on the rear deck in 6x9 slots but I have an adapter plate that will let them fit easily. Would this be too "good" for the rear fill? They will be powered by a PA 75x4 amp so power is not an issue. Before you give opinions that you wouldn't use a rear stage, please keep in mind that it's not my car and rear speakers are a must. I'm also curious how much more difficult it would be to tune correctly. Thanks for all the knowledge.

This was your original queston. I interpreted this as you know rear fill *****, but you're gonna do it anyway. Did I miss something? Why did you ask the question if you already know what you're gonna do?

You asked if components were "too good" for rear speakers. The answer is yes. Rear seat passengers' heads are right next to the speakers. A nice mellow set of 6X9 3-ways are fine. But if you already have something that'll fit, use them.

You also need very little power to make them heard from the back seat. Amping them is a waste of amp channels. Take my word for this - been there, done that. The more power you give them, the crappier your front stage gets... you can't "tune it correctly"... but you already knew that.

For the record, I like rear fill in my car. Without it, a big car sounds hollow. It also allows me to keep the volume low and still have the rear seat passengers hear the music when I have a full load of people.

95RAM
12-14-2004, 02:17 PM
3. you can run coaxials off Hu power without worrying about underpowering them....


:bsflag: My hu is definitely underpowering my pioneer coaxs.

audiolife
12-14-2004, 03:17 PM
unless its a convertable or a bus rear fill is almost a waste EVERYTIME. if i have doubters you dont have a clue about what a good frontstage is. only time i would ever recomend rears is if the only place you are going with your system is a dek and 4 other than that its a waste as well

themainjam
12-14-2004, 07:02 PM
:bsflag: My hu is definitely underpowering my pioneer coaxs.

LMAO he said cheap coaxials.... not ones that need to be powered..... :)

OdieTRP
12-14-2004, 10:09 PM
Maylar, that was exactly the type of answer I was hoping for, thank you. The only way I know is by research, not by personal experience. When I do my car I will certainly do only a front stage. I would like to do 6x9's but are there any "mellow" ones that are fairly inexpensive? I don't wish to open the box and waste the second set of Type X's when I can either sell them to someone who will appreciate them more or hang onto them for later. They are too deep for my own car so I have yet to decide what to do with them. Now I know that putting them on the rear deck would be a mistake and that was all I was looking for. I knew I would get a bunch of responses telling me that rear fill is a mistake but I was looking for facts based on experience, not useless opinion that does nothing to solve the problem. Thank you again.

95RAM
12-14-2004, 10:12 PM
Maylar, that was exactly the type of answer I was hoping for, thank you. The only way I know is by research, not by personal experience. When I do my car I will certainly do only a front stage. I would like to do 6x9's but are there any "mellow" ones that are fairly inexpensive? I don't wish to open the box and waste the second set of Type X's when I can either sell them to someone who will appreciate them more or hang onto them for later. They are too deep for my own car so I have yet to decide what to do with them. Now I know that putting them on the rear deck would be a mistake and that was all I was looking for. I knew I would get a bunch of responses telling me that rear fill is a mistake but I was looking for facts based on experience, not useless opinion that does nothing to solve the problem. Thank you again.


Facts are so overated! Do what i do just wing it.

themainjam
12-14-2004, 10:43 PM
http://forum.sounddomain.com/ubb/ultimatebb.php?ubb=get_topic;f=10;t=072875

check out the 6X9 but they have a high RMS :(

on the other hand he will sell them for abotu 25 buckS!! :)

squeak9798
12-15-2004, 09:37 AM
For the record, I like rear fill in my car. Without it, a big car sounds hollow.

I'm going to put in my personal opinion and disagree with that :) I've always driven "big" cars ('88 Bonneville 4-door, currently a '96 Olds LSS (Eighty-eight) 4-door), and I've never used rear-fill and never regretted it.


It also allows me to keep the volume low and still have the rear seat passengers hear the music when I have a full load of people.

That I will agree with :) The ONLY time I really recommend rear-fill is if you have a constant stream of rear-seat passengers who you want to be able to hear the music while it's down at a conversation level. But I also recommend fading most of the way back to the front when those passengers aren't with ya.

preunnerv6
12-15-2004, 11:38 AM
The the original poster:

I've run a setup without a sub before. I researched and got this as a suggestion.
Have you considered running a bandpassed rear fill? Before I got a sub, I had some front comps and bandpassed (about 100-3500 or so) STOCK 6x9's in the rear. (You could use any midbass/midrange speakers.) This gave me just a little bit more punch to the system and actually made the front sound BETTER than running the rears at full range or front comps only and no sub. At the same time, I never had a single passenger complain about the sound in the back. The bandpass was just enough to make them think they were hearing the full range, when really they were hearing the front comps and the rears were just pulling the sound together for them. It was really a win-win situation.

If I put together a system without a sub, this is my preferred setup. Only difference is that I may change the rear bandpass range or run it in mono. But it's based upon the acoustics in the vehicle. Just a thought. There are ways to get acceptable sound and output in the situation you describe.

OdieTRP
12-15-2004, 01:48 PM
The the original poster:

I've run a setup without a sub before. I researched and got this as a suggestion.
Have you considered running a bandpassed rear fill? Before I got a sub, I had some front comps and bandpassed (about 100-3500 or so) STOCK 6x9's in the rear. (You could use any midbass/midrange speakers.) This gave me just a little bit more punch to the system and actually made the front sound BETTER than running the rears at full range or front comps only and no sub. At the same time, I never had a single passenger complain about the sound in the back. The bandpass was just enough to make them think they were hearing the full range, when really they were hearing the front comps and the rears were just pulling the sound together for them. It was really a win-win situation.

If I put together a system without a sub, this is my preferred setup. Only difference is that I may change the rear bandpass range or run it in mono. But it's based upon the acoustics in the vehicle. Just a thought. There are ways to get acceptable sound and output in the situation you describe.

Again thanks for the input. What is bandpassing? If I could actually work on this system myself I might try this idea because it sounds ideal. Unfortunately a local shop is doing the install. In March I'll probably have a Class D amp and sub put in; at that time I should be able to do it myself. I'm having to compromise due to lack of time and money.

preunnerv6
12-16-2004, 08:58 PM
Bandbassing is sending a certain range of frequencies to a speaker. For instance, if the head unit had internal x-overs you could high-pass the rears at 100hz and then lowpass them on the amp. (EX: maybe your lowpass goes to 400hz). Then that would send about 100-400hz to the rear speakers, give or take considering the db slope.

Sometimes it can be even more effective if you wire the speakers in series, bridge the amp, and send them a mono signal. This will minimize any damage to the front stage and still give some rear fill. As I mentioned, I've done these tricks before. Rear passengers didn't notice because they were still getting most of their listening cues from the front speakers.

Nitropyro666
12-16-2004, 10:19 PM
i have no real help on this except as much as ppl hate lightning audio for the price they have good sound for a while if you dont blast them at max volumes.
And just have to comment i have no clue why ppl hate rear fill ive always had a van and think that rear fil helps with midbass and sq. i listen to rock? i HATED not having rearfill!
Danny