Alpine MRP-Mxxx; M= mono 1ch, T=two ch, F=four ch, and xxx=max 2 ohm RMS + 50 I think. Anyway, that should work much better than HU. You think the front speakers can't handle bass? In reality you should be able to turn the subs off, then play it and it should sound better than a stock system and sound good, except for the thump. But it should have bass, just not the real deep bass. If it does not then that is a problem. When you run the subs higher to help it, it screws up the directionality of the sound plus with a larger sub amp it is hard to blend it in. With a tight peaking sub box it is harder yet as it will peak ~100Hz and your high side is still dead at 100Hz. So you get loud powerful sub coming up to weak mids at your crossover point, and to work well that point needs to be lower, like 80Hz at the very highest. Subs should be run closer to 40-50Hz ideally, but hard to do in a car.
You get A LOT of hard kick drums but hardly any bass guitar response....I had it set before at 40-50hz by multi-meter and it hit too hard....That is what I mean by strong subs and weak front midbass. Where ever you set the crossover you will still get heavy on the notes and instruments in the subs, and weak on everything above playing out the mids. When you go high you get mid playing out of the subs and it sounds strange having stuff playing behind you. Sub bass is not directional under about 50Hz. And, if your subs are strong and peak high, they play higher than the crossover is set because the sub's curve is going up so high....it can over power the down slope of the LP crossover.
To get technical, if you have an even response everywhere then all music should sound good. Bass and midbass should be evenly produced.
To get technical, if you have an even response everywhere then all music should sound good. Bass and midbass should be evenly produced.
I'm still not willing to do it but how would you go about do that venting thing? That's unheard of to me...What do you do, hook some radiator hoses or something?
Like I said, I'm going to get my taxes done this weekend and see how they turn out. I have some choices still...I might look into getting 2 10" Kicker CVX subs and stick them in a nice big box in the back. They handle more power than regular 10's and can go into a bigger enclosure. Might give me the sound quality and bass I need as I think 10's are suppose to sound better with Rock music as well as they aren't as big as 12's and can move a lot faster. Or like I said before, other options include a better custom sealed enclosure for my current 12's, a ported (although the ported one didn't sound good on some songs this morning...Too much bass and didn't even have a good kick to it...Started to have too much push in it and that's why I don't like ported boxes) enclosure, still might look into 3 10's, might look into 1 15" or even 2 15's...
Looks like first things first is to try and get the kenwood tweets in and it looks like that's going to be some fun and I will be putting the sealed box back in this weekend. The ported one just doesn't sound good...
Anyways...Will have to see what the future holds for me...
Like I said, I'm going to get my taxes done this weekend and see how they turn out. I have some choices still...I might look into getting 2 10" Kicker CVX subs and stick them in a nice big box in the back. They handle more power than regular 10's and can go into a bigger enclosure. Might give me the sound quality and bass I need as I think 10's are suppose to sound better with Rock music as well as they aren't as big as 12's and can move a lot faster. Or like I said before, other options include a better custom sealed enclosure for my current 12's, a ported (although the ported one didn't sound good on some songs this morning...Too much bass and didn't even have a good kick to it...Started to have too much push in it and that's why I don't like ported boxes) enclosure, still might look into 3 10's, might look into 1 15" or even 2 15's...
Looks like first things first is to try and get the kenwood tweets in and it looks like that's going to be some fun and I will be putting the sealed box back in this weekend. The ported one just doesn't sound good...
Anyways...Will have to see what the future holds for me...
There are various ways of venting if you want to hack into the car. Me, I like my IB subs better than any vented box setup because they get low and I like more SQ...they get plenty loud enough for me so they may as well shake the car. I should have put some in the rear deck this time, but I figure with 4 12s I did not need to. Plus even with 4 12s I have nearly my whole trunk to use and no heavy box to carry around...but these subs are really heavy, too heavy IMO so I want to try something else.
You can't expect that ported box to sound good because it is not tuned to the drivers or the response you want.
You can't expect that ported box to sound good because it is not tuned to the drivers or the response you want.
Hey jol50... how are you doing an IB setup without the drivers facing into the cabin of your car?
Or did I miss something?
When I was running an IB setup in my car, it basically looked like this:
The main problem that Flyin is running into is that he's putting a box in the trunk with no way for the sound to pass through to the cabin... except by pushing the cones of his 6x9s. In some cars, this works fine because they have "leaky" trunks, but Hondas and most German cars have very tight trunks that do not allow for much leakage into the cabin. I have an Audi A4 with an extremely tight trunk, so I have 4 holes in the rear panel to let sound pass from the sub in the trunk to the interior of the car. Sounds awesome.
In the old days, some used to use dryer hoses to vent into the cabin. Something like this:
Flyin doesn't want to tear up his car, so this may not be the best solution for him.
As for minimum cutting, he could somehow enclose the backs of the 6x9s (Crutchfield has foam backs that would work fine) and open some small holes in the rear deck cover that would remain under the rear deck cloth, but allow the sound from the trunk to enter the cabin... essentially, that's how my setup is done. If you'd like to see some pictures, I suppose I could break out the camera this weekend and show you that it looks really good, but allows the sound through.
Or did I miss something?
When I was running an IB setup in my car, it basically looked like this:
Code:
[FONT=courier new]- ----- - rear deck (with holes to vent to cabin)
\ / \ /
--- ---
--- ---
[/FONT]The main problem that Flyin is running into is that he's putting a box in the trunk with no way for the sound to pass through to the cabin... except by pushing the cones of his 6x9s. In some cars, this works fine because they have "leaky" trunks, but Hondas and most German cars have very tight trunks that do not allow for much leakage into the cabin. I have an Audi A4 with an extremely tight trunk, so I have 4 holes in the rear panel to let sound pass from the sub in the trunk to the interior of the car. Sounds awesome.
In the old days, some used to use dryer hoses to vent into the cabin. Something like this:
Code:
[FONT=courier new]
---- ------ rear deck (with hole to vent to cabin
| | hose
------------
| \ / | driver in box shooting sound through tube
| --- |
------------
[/FONT]Flyin doesn't want to tear up his car, so this may not be the best solution for him.
As for minimum cutting, he could somehow enclose the backs of the 6x9s (Crutchfield has foam backs that would work fine) and open some small holes in the rear deck cover that would remain under the rear deck cloth, but allow the sound from the trunk to enter the cabin... essentially, that's how my setup is done. If you'd like to see some pictures, I suppose I could break out the camera this weekend and show you that it looks really good, but allows the sound through.
In my experience if you use a tube of some kind it turns into a port and thus tunes a specific frequency. I built a baffle that runs from the floor/seat up to the rear deck. In the face (baffle board) I put 4 12s. I took the cover off the seatback and adjusted the seat so it is not tight to the rear deck, also it is just the foam pad of the seat left. I put peel and stick all around it and on rear deck, and its built out of 3/4" ply and covers/supports most of the rear deck as well. They have no problem pushing that seat around, and the rear window, deck lid, roof, etc. Having them visible in the rear deck is an advantage and better than a manifold of some kind. In this car I did not want to hack it up and still could only fit two in there, would have to make a grill to keep them stealth, etc.
In one car I had two 10s and 6x9 in rear deck, plus two 10s into rear seat like this. It worked very well and the top pair did have more output. I never had a problem with the 6x9, but other cars did and I had to put a solid box over them to stop it. It seems to depend on size of trunk vs. drivers. With a pair of 10/12s it was not an issue for good 6x9 IMO. They did not move much and even testing it seemed to make no difference. Trunks have a lot of leaks and flex unlike a box....complex shapes and deadening of some kind too. IB is more forgiving than a box maybe, even with leaks they can work well don't let anyone fool you. They are power limited though, but if you hit xmax you are doing something...and I like my 30Hz, even 25. In fact I have a new test CD to try in it, have to do that.
I have seen people make assorted band pass boxes. They put the ports outside the box enough to poke them into the rear deck. They worked but I did not like the sound of them, it could be the phasing. IB in the rear deck puts the sound right there close and in sight. If you get a rattle in a sub you know right away. I've also seen/built manifolds and such that go up to rear deck and have to say I don't like those either but they do work. Slot ports, didn't car for those either LP made one once and a flat board on the deck would do more. Now if you want spl then you need a box, though with a parametric I can bump up 50Hz all I want...which is never for me.
Maybe you should pull the seat out and remove some stuffing there?
In one car I had two 10s and 6x9 in rear deck, plus two 10s into rear seat like this. It worked very well and the top pair did have more output. I never had a problem with the 6x9, but other cars did and I had to put a solid box over them to stop it. It seems to depend on size of trunk vs. drivers. With a pair of 10/12s it was not an issue for good 6x9 IMO. They did not move much and even testing it seemed to make no difference. Trunks have a lot of leaks and flex unlike a box....complex shapes and deadening of some kind too. IB is more forgiving than a box maybe, even with leaks they can work well don't let anyone fool you. They are power limited though, but if you hit xmax you are doing something...and I like my 30Hz, even 25. In fact I have a new test CD to try in it, have to do that.
I have seen people make assorted band pass boxes. They put the ports outside the box enough to poke them into the rear deck. They worked but I did not like the sound of them, it could be the phasing. IB in the rear deck puts the sound right there close and in sight. If you get a rattle in a sub you know right away. I've also seen/built manifolds and such that go up to rear deck and have to say I don't like those either but they do work. Slot ports, didn't car for those either LP made one once and a flat board on the deck would do more. Now if you want spl then you need a box, though with a parametric I can bump up 50Hz all I want...which is never for me.
Maybe you should pull the seat out and remove some stuffing there?
Mostly done with temp wiring, and no I don't like that amp. One sub is newer.
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An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
I see... nice solution... by moving and modifying the seat, you're giving the sound a path into the cabin. That's the piece that Flyin is missing with the current solution.
The tube solution will create a virtual bandpass box, with the sub box acting as the internal volume, the trunk as the second chamber volume, and the tube as the "tuned port" (lol). Lots of output and if you tuned it just right, you could balance the output with the horns under the dash. The old days were the old days because we didn't know better.
On the 6x9 thing, I see what you're talking about... but it's a different case. You had the 6x9s sharing the space with your IB... they were all essentially sharing a single box (the trunk.) In Flyin's case, he's got the box *in* the trunk providing all of the air movement and the 6x9s are in the rear deck between the subs and the listener. So the air movement from the subs is pushing the cones of the 6x9s on every bass hit.
To relate it to your current setup, imagine that your manifold feeds into a stiff, sealed panel that has 2 6x9 drivers on it rather than the back of the modified seat. What's gonna happen when the bass hits? Yep, the cones on the 6x9s are gonna LEAP forward, which will make the midrange sound distorted as heck. This may explain why Flyin's hearing so much hash when he cranks up the volume... it's not really the front speakers making the noise, it's the back ones.
The tube solution will create a virtual bandpass box, with the sub box acting as the internal volume, the trunk as the second chamber volume, and the tube as the "tuned port" (lol). Lots of output and if you tuned it just right, you could balance the output with the horns under the dash. The old days were the old days because we didn't know better.
On the 6x9 thing, I see what you're talking about... but it's a different case. You had the 6x9s sharing the space with your IB... they were all essentially sharing a single box (the trunk.) In Flyin's case, he's got the box *in* the trunk providing all of the air movement and the 6x9s are in the rear deck between the subs and the listener. So the air movement from the subs is pushing the cones of the 6x9s on every bass hit.
To relate it to your current setup, imagine that your manifold feeds into a stiff, sealed panel that has 2 6x9 drivers on it rather than the back of the modified seat. What's gonna happen when the bass hits? Yep, the cones on the 6x9s are gonna LEAP forward, which will make the midrange sound distorted as heck. This may explain why Flyin's hearing so much hash when he cranks up the volume... it's not really the front speakers making the noise, it's the back ones.
IB is freeair. I didn't cut anything in the car. If I take it out only screw holes will be left and not in any visible place really. I sealed the frame in with foam tape and it is not in pics but put peel and stick over the inside and any holes/cracks in metal. It would have been easier to run two 15s right into the seat and not make the angled frame, but 4 12s sounded like a better idea at the time. Only thing in front if the subs is the cushion of the seat that is about 2-3" foam on a metal frame. There is maybe 1" gap at the top and it is sprung so it does not vibrate. If someone sits in there it just goes back to the deck. Some of that gap is from the panel that used to cover the back of the seat that is now stored in the shed. I bent the brackets out maybe 1/2" at most and put a little foam behind the cushion frame.
You still get back waves off the IB but yes they are mostly out of phase with the 6x9. Can still mess them up at times. I have had boxes too and sometimes it did others it did not. If it is bad the foam baffles will not work. I guess I consider it a normal course of things to check that kind of stuff out, so I always did. I have a friend with 6 10s in the back IB and he had to make boxes for the 6x9 when he had them in there.
All my mids are in the doors in this car, no 6x9 but planning on putting them in rear doors. They work really nice when you are outside the car; hard to hear the fronts. I dial them back in the car but this car the rears are same distance from you as fronts anyway. Audiophiles hate that but it sounds great with them faded in a little, more like headphones.
You still get back waves off the IB but yes they are mostly out of phase with the 6x9. Can still mess them up at times. I have had boxes too and sometimes it did others it did not. If it is bad the foam baffles will not work. I guess I consider it a normal course of things to check that kind of stuff out, so I always did. I have a friend with 6 10s in the back IB and he had to make boxes for the 6x9 when he had them in there.
All my mids are in the doors in this car, no 6x9 but planning on putting them in rear doors. They work really nice when you are outside the car; hard to hear the fronts. I dial them back in the car but this car the rears are same distance from you as fronts anyway. Audiophiles hate that but it sounds great with them faded in a little, more like headphones.
I get what you are saying by the waves maybe pushing the 6X9's up and done but the subs aren't pointing up. They are faced towarss the back of the trunk. I don't see how that could affect how the 6X9's are moving as the waves should bounce off the back of the trunk and towards the back of the seats. I would believe it more if I had my speakers top mounted but they aren't, they are faced out at the back of the trunk. Although, a custom box builder I talked to told me the only way to get the cubic footage I was looking for and have it sound good in my car was to have them firing up...
Flyin
i know you don't want to remove the 6x9's so here are other ideas:
1:you could temporarly pull your rear shelf cover and cut several small vent holes in the metal framing with a hole saw to let the bass in and once you put the cover back you woun't see them. i know you don't want to cut but some sacrifices usually must me made for good sound.
2: do you have a rear center armrest or ski pass through? if so you could cut out the panel area behind it to let bass in with the arm rest down. some people even install a round tube or sqaure mdf port here for the bass to enter. or you could just cut the metal out and carpet or whatever back over the panel to make it look stock yet still be breathable. the ski pass in my bmw was easy to knock out with a rubber mallete and the foam layer in that area was also perforated to be pulled out as a dealer option so i just yanked it out to let the bass in.
3: if you don't have the armrest you could pull the carpet from the rear of the back seats and cut vent holes in it in evenly spaced areas and then put the carpet back on and it will look stock but let the bass in.
4: the foam covers are a good idea for the 6X9's. it will clean up the sound from them. i usualy put a bit of polyfill stuffing in there to to clean up the sound further. some people like to put a band-pass filter on the rear fill so they don't play bass or high-highs and attenuate them a bit so they act like a reflection off the sound from the front as in a concert hall and that way it won't sound like the band is playing behind you and you are facing the opposite way.
5: and if you don't want to cut at all you could loosen the rear seat frame mount on the top only and put some small spacers in there to allow a small vent at the top forr the bass. this method is fully reversible but it usually takes a combination of methods to get the most bass through. i would also consider getting a custom box tailor made to suit your subs and to get closest to the sound you want. a good shop will know how to do this. or if you feel like doing some woodworking you could get the specs and try to build one yourself.
Trial and Error and a lot of hard work are the best ways to get things sounding the way you like. Don't be afraid to experiment, carefully that is
i know you don't want to remove the 6x9's so here are other ideas:
1:you could temporarly pull your rear shelf cover and cut several small vent holes in the metal framing with a hole saw to let the bass in and once you put the cover back you woun't see them. i know you don't want to cut but some sacrifices usually must me made for good sound.
2: do you have a rear center armrest or ski pass through? if so you could cut out the panel area behind it to let bass in with the arm rest down. some people even install a round tube or sqaure mdf port here for the bass to enter. or you could just cut the metal out and carpet or whatever back over the panel to make it look stock yet still be breathable. the ski pass in my bmw was easy to knock out with a rubber mallete and the foam layer in that area was also perforated to be pulled out as a dealer option so i just yanked it out to let the bass in.
3: if you don't have the armrest you could pull the carpet from the rear of the back seats and cut vent holes in it in evenly spaced areas and then put the carpet back on and it will look stock but let the bass in.
4: the foam covers are a good idea for the 6X9's. it will clean up the sound from them. i usualy put a bit of polyfill stuffing in there to to clean up the sound further. some people like to put a band-pass filter on the rear fill so they don't play bass or high-highs and attenuate them a bit so they act like a reflection off the sound from the front as in a concert hall and that way it won't sound like the band is playing behind you and you are facing the opposite way.
5: and if you don't want to cut at all you could loosen the rear seat frame mount on the top only and put some small spacers in there to allow a small vent at the top forr the bass. this method is fully reversible but it usually takes a combination of methods to get the most bass through. i would also consider getting a custom box tailor made to suit your subs and to get closest to the sound you want. a good shop will know how to do this. or if you feel like doing some woodworking you could get the specs and try to build one yourself.
Trial and Error and a lot of hard work are the best ways to get things sounding the way you like. Don't be afraid to experiment, carefully that is
Flyin11 said:
Bass waves are very long, that is how they reach our ears up front in the first place. your trunk is getting pressurised by the bass and the 6x9's will be moved by this. just pull the wires from them or fade them out and see for yourself. this will happen no matter what way the box faces because they are sharing the same air space. the foam covers from crutchfield will help with this. have you tried swithcing the polarity on the 6x9's to see if the sound improved yet? sometimes it helps. same with the sub polarity one way ore another.
Just got a quote from a very good enclosure fabricator and this is what he said he could do for me for a ported box for $139...Does this sound good?:
After reading a bit more on the subs, I think if you go with a ported enclosure and tune it up just a bit, it will do the job you are looking for. JL recommends that the subs should be tuned @28Hz, that is very, very low. And from what I remember, because you like more rock type music, I felt a sealed enclosure would do the best, but, I ran it at 32Hz ported, and I got very good output and response, so I think this design is the way to go; 14"H x 32"W x 21.25"D, 4.357^3ft gross vol. Slot port, 12.5" x 2.5" x 20.8"long@32Hz. After all displacement, 3.550^3ft net box vol. Built from 3/4" Perfecta UL-MDF. Seams matched and double sealed. Reinforced baffle board. Dado cut end caps. Seams fastened with Tite Bond glue and 1-5/8" counter sunk drywall screws. Walls fully braced and tied in with Maranti Hardwood bracing for Zero wall flex and 100% cabinet integrity. 45 degree boards in the corners to kill standing sound waves and to add extra strength to the corner seams. All internal port edges are beveled. High Quality, Gold plated binding post with nylon heads. Ports painted black or a color of your liking. Gray Muzicon carpet. This enclosure will give you better output & sound quality. You will gain at least two db with the port.
After reading a bit more on the subs, I think if you go with a ported enclosure and tune it up just a bit, it will do the job you are looking for. JL recommends that the subs should be tuned @28Hz, that is very, very low. And from what I remember, because you like more rock type music, I felt a sealed enclosure would do the best, but, I ran it at 32Hz ported, and I got very good output and response, so I think this design is the way to go; 14"H x 32"W x 21.25"D, 4.357^3ft gross vol. Slot port, 12.5" x 2.5" x 20.8"long@32Hz. After all displacement, 3.550^3ft net box vol. Built from 3/4" Perfecta UL-MDF. Seams matched and double sealed. Reinforced baffle board. Dado cut end caps. Seams fastened with Tite Bond glue and 1-5/8" counter sunk drywall screws. Walls fully braced and tied in with Maranti Hardwood bracing for Zero wall flex and 100% cabinet integrity. 45 degree boards in the corners to kill standing sound waves and to add extra strength to the corner seams. All internal port edges are beveled. High Quality, Gold plated binding post with nylon heads. Ports painted black or a color of your liking. Gray Muzicon carpet. This enclosure will give you better output & sound quality. You will gain at least two db with the port.
Yeah...I understand all that...If it'll give me what I'm looking for bass wise then it's all good. I might plan on getting some really good 6 1/2's in about a month or 2 as well. We'll see what my taxes give me after this weekend. I now have to get these tweeters hooked up and re do the wiring to my fronts so I can go ahead and turn the gain up on my highs to get them to sounding louder than what they are now.
The best cheapest option would be to just pull the rear plastic deck out and remove as much metal from the rear dash as possible without degrading the structural integrity of the 6x9 mounting points. Then install the foam baffles under the 6x9's to help them a little more. (like someone already mentioned) The only way the bass pressure will make it into the cabin efficiently will be with an easy airway. When you put the rear plastic deck cover back in you won't even be able to tell it is cut underneath without looking from underneath in the trunk area.
You would be able to cure your issue by overpowering the trunk seal with a huge amp and massive subs, but that is a waste of money when you could just clear the path for better airflow and let the subs you have do their job.
You would be able to cure your issue by overpowering the trunk seal with a huge amp and massive subs, but that is a waste of money when you could just clear the path for better airflow and let the subs you have do their job.
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