Sub and Midbass for Alpine/BA system

[tsombrero]

I'm working out the kinks in a new-ish system and was hoping you lads might have some input. I have BA SX60 components and an Alpine 70x4 amp. Alpine HU. No sub yet.

Anyway the SX60's fall off very quickly below 500hz, and most subs only go up to 2-300hz or so. Some cheaper ones (Pioneer) claim to go >1000hz but of course there is no response curve available so some skepticism is due.

I am looking for a nice flat response curve in my system down to 60hz or so. Is that possible with my components plus some sub? A big hole between 200-500 hz would drive me nuts.

[nicks84]

Originally Posted by tsombrero

I'm working out the kinks in a new-ish system and was hoping you lads might have some input. I have BA SX60 components and an Alpine 70x4 amp. Alpine HU. No sub yet.

Anyway the SX60's fall off very quickly below 500hz, and most subs only go up to 2-300hz or so. Some cheaper ones (Pioneer) claim to go >1000hz but of course there is no response curve available so some skepticism is due.

I am looking for a nice flat response curve in my system down to 60hz or so. Is that possible with my components plus some sub? A big hole between 200-500 hz would drive me nuts.

What do you have your crossover set at ? Maybe try turning it down a little ?

[tsombrero]

Originally Posted by nicks84

What do you have your crossover set at ? Maybe try turning it down a little ?

The amp (actually set up for 80 RMS x2) is set up with a high-pass at 100hz... the speakers don't really go that low and setting that way seems to boost the mids a bit. The SX60's have a crossover but the only adjustment is the treble attenuation (already set for minimum treble.. these speakers are too bright for me I think).

Anyway I guess a better way to phrase my question is: are any good subs effective through the entire 60hz-500hz range?

[nicks84]

Originally Posted by tsombrero

The amp (actually set up for 80 RMS x2) is set up with a high-pass at 100hz... the speakers don't really go that low and setting that way seems to boost the mids a bit. The SX60's have a crossover but the only adjustment is the treble attenuation (already set for minimum treble.. these speakers are too bright for me I think).

Anyway I guess a better way to phrase my question is: are any good subs effective through the entire 60hz-500hz range?

Ive seen a few to be honest, but IMO, I think a sub shoudl be cutt no higher than 120 - 180 Hz. Perhaps it coudl be the installation, I've been told that in cases like that, a baffle is used behind the mids. It seemed to work wonders for 900 and below. If that is not an option, then I guess you can find a sub that goes that high.

I have a freind that has the same problem, but hers are in the door of a 89 Mazda. The person she bought it from made custom panels, but did not do such a good job. He just made a 3 inch thick layer of carpet. Anyways, she has no response from like 500 to 80. IT sounds rather unpleasing to the ear. You could be havin a similar situation ?

[tsombrero]

Originally Posted by nicks84

I have a freind that has the same problem, but hers are in the door of a 89 Mazda. The person she bought it from made custom panels, but did not do such a good job. He just made a 3 inch thick layer of carpet. Anyways, she has no response from like 500 to 80. IT sounds rather unpleasing to the ear. You could be havin a similar situation ?

That sounds about right.... I have Raammat stuff in the door (the sticky rubber-foil stuff and a layer of the thin closed-cell foam stuff) but maybe that is not enough.

In the spirit of throwing money at the problem, I just ordered a set of Diamond Hex's. They should handily outperform the BA's in the midrange and the silk-dome tweeters should take the edge off the highs. Unfortunately nobody within 100 miles of Seattle sells Diamonds so I bought from an ebay seller of questionable repute, so let's hope they show up opcorn:

[nicks84]

Originally Posted by tsombrero

That sounds about right.... I have Raammat stuff in the door (the sticky rubber-foil stuff and a layer of the thin closed-cell foam stuff) but maybe that is not enough.

In the spirit of throwing money at the problem, I just ordered a set of Diamond Hex's. They should handily outperform the BA's in the midrange and the silk-dome tweeters should take the edge off the highs. Unfortunately nobody within 100 miles of Seattle sells Diamonds so I bought from an ebay seller of questionable repute, so let's hope they show up opcorn:

I agree the Hex will outperform the BA's you have. But heres the deal. I have a set of HEX in my car. DEF a good set IMO. Plenty of crisp clear sound, volume. They sound very pleasant to me. And yes, the Silk , will definately take the edge off. But I find they lack in midbass. That is of course compared my Q series. But, you will be very happy with them, I just find them to be a lil lackin on the midbass range. And that seems to be what you are looking to acheive. But install is but I find they lack mid bass, and that is of coursse compared to the Q's. Maybe if I just had all Diamond, I wouldnt notice the difference because it woudl all be the same source? But anyways, NICE set of comps, I think you will like them.

[tsombrero]

Originally Posted by nicks84

I agree the Hex will outperform the BA's you have. But heres the deal. I have a set of HEX in my car. DEF a good set IMO. Plenty of crisp clear sound, volume. They sound very pleasant to me. And yes, the Silk , will definately take the edge off. But I find they lack in midbass. That is of course compared my Q series. But, you will be very happy with them, I just find them to be a lil lackin on the midbass range. And that seems to be what you are looking to acheive. But install is but I find they lack mid bass, and that is of coursse compared to the Q's. Maybe if I just had all Diamond, I wouldnt notice the difference because it woudl all be the same source? But anyways, NICE set of comps, I think you will like them.

Hey, thanks for the input... I will let you know when/if the Hex's show up how they compare to the BA's. I looked at the MB Quart stuff but titanium tweeters are generally too bright for my taste. Wish I could find a local dealer so I could actually hear these things! The only non box-store dealer I found in town sells Morel stuff... too rich for my blood.

[alphalanos]

You should be able to cross your mids around 100Hz and your sub(s) around 80, so the hole should be minimal. A good set of mids installed correctly should give you decent midbass down to 100Hz easily. I have a rather inexpensive set of CDT CL61 in my doors (very well deadened) and they have decent low end response.

[PaulD]

a 6.5" mid should have plenty of sound down to below 100 Hz. Make sure the speaker is playing into the door and not in a "box". They are designed as free air speakers.

[tsombrero]

Originally Posted by PaulD

a 6.5" mid should have plenty of sound down to below 100 Hz. Make sure the speaker is playing into the door and not in a "box". They are designed as free air speakers.

Thanks but what do you mean "playing into the door"? Pardon my ignorance here. They're bottom-mounted on the door panel (thin fiberboard) and the door skin sheet metal is moderately dampened. There is a vapor barrier (sheet plastic) directly behind the speaker, protecting it and the panel from moisture.

Hmm. Do you suppose the fiberboard panel is too flexible, absorbing some of the energy that should be going to the driver? It is a rather flimsy door panel and the speaker is not attached to anything else.

[alphalanos]

Yes you probably should cut a ring out of 3/4" MDF and mount it solidly to the door. Add more dampening if you can. Make sure the front of the speaker is completely separated from the back (make sure you have a tight seal)

In my doors I have the panel bolted to the door skeleton with 4 screws around the mid and then the FG peice is bolted to the door panel. The mid itself is attatched with 8 screws. I made the cutout for my mid a bit small so that it is very tight. The tighter and more deadened you doors are, the better. Vibration causes lost energy which affects quality.

*playing into the door means the mid is not in a sealed enclosure. Mid ranges are designed to be infinite baffle, which is why the door needs to be well dampened.

[tsombrero]

Many thanks for the thoughtful responses, guys. Things are starting to make sense now...

BTW I bet some of that plastic cutting board stuff would age better than MDF since it will be exposed to moisture inside the door. It's strong and cuts great with a bandsaw if you have one. Just a thought for future noobs like me.

[PlayStation3]

Originally Posted by tsombrero

Many thanks for the thoughtful responses, guys. Things are starting to make sense now...

BTW I bet some of that plastic cutting board stuff would age better than MDF since it will be exposed to moisture inside the door. It's strong and cuts great with a bandsaw if you have one. Just a thought for future noobs like me.

MDF covered with fiberglass resin i beat would 1 be stronger and 2 would be cheaper and age just fine.