So, I've got two boxes, sealed and bandpass. What I've heard is that bandpass is suppose to give more deep bass, or "ghetto" bass, but isn't as accurate and tight as a sealed box. For the most part I've noticed this true, but the bandpass box only sounds good with certain songs and types of bass. As some people have said it only sounds good with certain frequencies of bass.


What I want to know is if I need to change amp settings such as LPF to work better with the box? or maybe a different bandpass box.

I've heard another system with a bandpass, and it sounded 10 times better than mine. A lot more deep and more clarity. I don't know if JBL passes up Kenwood in quality? or what. So, I know that bandpass can sound good, I'm just unsure of what I need to change in my setup.

 

is it a prefab bandpass box or did you build it? is it a 4th order or a 6th order? a bandpass is louder. if you want sound quality you are going to want to go with that sealed box. bandpass can sound really good but you need to really know what you are doing.
a bandpass does not get lower.
you can tune a ported box to be low and sealed boxes can get really low as well.


either way for your bandpass to be tuned properly you need to find out what you are tuned to on both the low end and the high end.

here are the formulas for a fourth order.
Fourth Order Bandpass Subwoofer Box Equations Formulas Design Calculator fb Tuning Frequency

sealed boxes: limited by the mechanical limits of the woofer
ported: still limited by the mechanical limits of the woofer. you also have a tuning. that tuning is going to be slightly lower than where the woofer is most efficient (not accounting for resonance of the vehicle and a whole bunch of other stuff.) but it is on the lower end of the spectrum or your lpf.
bandpass: still limited by mechanical limits of the woofer. you will have a low end tuning (lpf) and a high tuning (hpf) in between those is where the woofer is most efficient. going beyond that filter in either direction can cause damage and distortion.

thats just the box. The other vehicles you heard these other setups in were they the same vehicle (different vehicle resonate differently), where they the same power (as far as same wattage subs). there are a ton of factors that can cause a single setup to sound different from vehicle to vehicle and twice that many to cause one setup to sound different than a completely different setup in a different vehicle.


is your goal to have a better sounding system? a louder system?
do you want to use the bandpass?
if so, and you want to tune it to sound better you will need to know the tuning. (the formulas I posted above)

if you just want it to sound better there maybe an easier solution than the bandpass. If you want the bandpass I will try to help you but I dont know a whole lot about them. KHA may know more.

 

I'm not exactly sure. It's a probend competition bandpass box by R/T.
I have noticed a lack of sound quality with the bandpass v. the sealed. The only reason I was willing to try out the bandpass was because I heard it in another system, and it sounded great. It didn't lack quality and the bass was extremely deep. So, that's why I thought the bandpass box would be deeper, but maybe I was wrong.

The car was a 87 seville I'm pretty sure. I have a 94 accord sedan. My system as of now. Is 1800 watt mono block powering 2 kenwoods at 2 ohms at 400rms each. There's an excess of 50 watts rms per. The other system was two jbl with 2 600 watt amps. The other specifics of that I'm unsure.

Overall goal is probably deeper bass without losing too much sound quality. My sealed sounds great, but the trunk rattle overtakes it. I've noticed that the bandpass seems to eliminate some of that rattle, but my box creates new rattle with the fiberglass. That's probably just a problem with my box since it's rather old. Maybe a newer box would fix that? Also, the subs that were in the box only operated at 100 rms each. So maybe my subs are just too high for that box to maintain.

I'll try looking at those formulas and see what I can do with that.

Thanks.

 

really in you dont want to go to in depth with it all just pull the specs on your subs and build a custom box. typically sealed will have better sq. ported will be louder. I have mine in a ported box and they are louder than when they were in a sealed box but I dont think I lost much sq with the port. just makes sure your tuning is good and your amp is set right and you would be good. The box is the most influential thing about how a sub will sound. those kenwoods specs as far as power are right about the same as my diamonds. I am running about 1k watts rms (before accounting for box rise) in a 4 cubic foot ported box tuned at 34 hz. I really like the way it sounds.

also in which direction was your sub firing. if you really dont like trunk rattle you may consider an IB setup.

judging by the picture it looks like that box maybe a 4th order.

 

Alright, yeah I was beginning to think that. I was just surprised by the power the box delivered. So, that's why I even considered it. Well, with the bandpass I was facing them towards the front of the car. The only problem with that was I could hear the fiberglass. Ha. I'm pretty sure the box is crap or can't handle that amount of power. I didn't like it facing the other way since I lost the kick. No movement in my mirrors. Which I use to gauge. I like bass that doesn't attack the song as much as blend.

I'll probably just go back to my sealed and hope that the increase in power and age of my subs surpass my older system.

 

good discussion so far.

you want to specifically build a bandpass box for the subs you intend on using. bandpass does exactly as the name implies - it filters low frequency and high frequency, like a bandpass filter. the best bandpass enclosures i've heard were made by Orion in the 90's using their XTR series of woofers.

you're doing the right thing by experimenting. that's the only way to know for sure. but adding a little math in there to calculate what the expected response is can help with making decisions.

I like to gauge bass by it's ability to blend with the sound stage by sounding like it's in front of me. for that, you need midbass support from the front speakers.

 

Yeah, I wasn't sure it had to be specifically built for the subs. So, that was my mistake. I had no idea the amount of work you had to go through to make a bandpass box work. It's almost discouraging to even want to use one when you can just get a sealed box and be done with it. ha.

 

If you want bandpass, buy a good quality pre-made one. But bandpass isn't worth it, IMO.

Sell the bandpass box on CL.

 

if you really wanted bandpass you could do some searching and I am sure you could find an experienced box builder and get a bandpass designed for your subs. that would save you the headache and it would get you the bandpass. I agree with KHA that it is not worth it. It would cost you but it would be no headache to you.

 

By this, I should clarify that I mean buying a nice premade box and sub combo. Not an empty box like you pictured.

If you use box building software and accurate sub T/S parameters, you can hash out the design electronically.