Dual subs, ported and sealed

[Tungsten06GT]

Hey guys,

After reading the thread about matching 2 different types of SVS subs, I was kind of wondering, has anyone ever matched a sealed and a ported sub together, ie. eD's A3-300 and the A5s-300? Granted their amps are different, but their drivers are the same.

Just curious if this would provide good results and save you some space at the same time.

Thanks

 

[j_garcia]

I had a Franken-SVS that was a Plus using a passive radiator and it sounded pretty good in my room with my vented beast. It does make it a little more difficult to integrate the two, but it depends on your room too.

 

[Tungsten06GT]

Setting up a ported and a sealed together would probably be more difficult than 2 exact matches though right?

 

[j_garcia]

I would think so. Identical subs will have the same room modes, where two different subs will almost certainly have different ones.

 

[Tungsten06GT]

Well I'm not sure if another sub would help me or what, but maybe I'll drift off the subject for a second.

Does it seem normal for a ported sub to have "weaker" bass when listening to music vs the music/LFE in movies and on tv? Because with movies, the sub really cranks out a ton of output, but when I have a CD in, the driver is barely moving, it just seems weak. Is this a setup issue or receiver issue or am I crazy haha?

 

[bandphan]

if you wanna start tweaking, get a dcx2496 from behringer and start using rew and you can address all issues

 

[highfigh]

I would think so. Identical subs will have the same room modes, where two different subs will almost certainly have different ones.

You mean, the different woofers will excite some modes to a different extent, right? It's the room that has modes, not the speaker(s).

 

[Tungsten06GT]

Haha I probably wouldn't know what the heck I'm doing!

Maybe it's my source; should the PS3 be ok for CD playback?? Music just doesn't sound as clear and powerful as from movies/tv..

 

[shadyJ]

A lot of music doesn't put emphasis on the bass regions, unlike many movie soundtracks. There are exceptions, such as raggea, hip-hop, and drum'n'bass. Even a lot of hip hop doesn't have the bass that you would expect though. Throw in a Drum'n'bass CD to see what the bass truly sounds like, so at least you can rule out the recordings as a cause. Also the PS3 might be playing back the CD's at a different level than DVD's. The CD's you are putting in might not have the compression that movie soundtracks can have either.

As far as matching a ported and sealed subwoofer, that really depends on the situation. You would need to do it in a way that doesn't strain one sub or the other, and that would be tricky because the strength and weaknesses of each sub type is different.

 

[Tungsten06GT]

Those are some really good points thanks. That actually makes a lot of sense thinking about it. I'm pretty sure the PS3's level for CD playback is the same for movies...

But here's why I'm questioning.. I just put in one of those "maximum bass" CD's, with crazy amounts of bass. And, the output is loud, but it seems like I lose alot down at 40hz and below. Now, I don't have any way to really get a good frequency sweep analysis, but what I'm comparing to is what I have in my car, which may sound rediculous but stick with me here. I have a single 13w6v2 in a sealed box in the trunk of my Mustang (small cabin), so with the bass cd in there you feel like your eyes are going to bleed. The entire cabin shakes, and the bass, while not the smoothest, is just so prominant, it makes u vibrate all over.

Now, switch over to my A3-300 in my house, 13x20x8 room with an entrance going into a dining room and then into the kitchen. The sub is in a corner in the living room (not great I know), but it "feels" like I'm getting a small fraction of what I feel in my car. Obvious question, but is that because of the muuuuuch smaller volume of my car? Or, should I be able to feel 40hz and below like I do in my car, or does my positioning suck majorly in the room?

I'm still workin out my noobness I think...

 

[Tungsten06GT]

Also note, I am only referring to music (rap, bass cd)... Just pure tones basically.

Movies absolutely shake the house. I'm just so confused at this difference

 

[highfigh]

Those are some really good points thanks. That actually makes a lot of sense thinking about it. I'm pretty sure the PS3's level for CD playback is the same for movies...

But here's why I'm questioning.. I just put in one of those "maximum bass" CD's, with crazy amounts of bass. And, the output is loud, but it seems like I lose alot down at 40hz and below. Now, I don't have any way to really get a good frequency sweep analysis, but what I'm comparing to is what I have in my car, which may sound rediculous but stick with me here. I have a single 13w6v2 in a sealed box in the trunk of my Mustang (small cabin), so with the bass cd in there you feel like your eyes are going to bleed. The entire cabin shakes, and the bass, while not the smoothest, is just so prominant, it makes u vibrate all over.

Now, switch over to my A3-300 in my house, 13x20x8 room with an entrance going into a dining room and then into the kitchen. The sub is in a corner in the living room (not great I know), but it "feels" like I'm getting a small fraction of what I feel in my car. Obvious question, but is that because of the muuuuuch smaller volume of my car? Or, should I be able to feel 40hz and below like I do in my car, or does my positioning suck majorly in the room?

I'm still workin out my noobness I think...

The way a subwoofer couples with the car interior is completely different from the way it couples with a room. A car interior allows the sound from a woofer to compress the air to a greater extent that in a larger room and that means it moves your body as well as the car's interior panels and you're feeling it from three sources- the direct sound, the vibrations of the car and the vibrations that are radiated by the car. Another factor is that a room has modes, or specific standing waves that are directly related to its dimensions and depending on where you are in that room, you'll hear the bass to varying degrees because of where and how the standing waves intersect.

By being in the trunk, if the conditions are right, the trunk can act as a horn and certainly like a bandpass enclosure. This is why the sound changes so drastically when you open a window- the tuning has changed.

 

[skers_54]

Most music doesn't have much below 40 Hz, so that would explain why you feel the lowest lows are missing. Cars also have much more gain and a smaller area to pressurize, so it's difficult to get the same effect in a house.

 

[highfigh]

Most music doesn't have much below 40 Hz, so that would explain why you feel the lowest lows are missing. Cars also have much more gain and a smaller area to pressurize, so it's difficult to get the same effect in a house.

There's a lot below 40Hz, in a lot of music. A 5 string bass often has a B string below the normal E and the E is tuned to about 41Hz. IIRC, the B string is tuned to about 34Hz and that will make some speakers puke, especially ported woofers tuned above that frequency. Kick drum can be close to the same range and synths can go to 1Hz, if needed, so Techno and other music that's synth-heavy can really test speakers in a hurry.

 

[Tungsten06GT]

Ok thanks for the clarification. I just wanted to make sure my woofer wasn't damaged, or that I really messed up with room placement.

Perhaps I should have done some auditioning with HT subs before I placed judgement on my setup. This is just all so new to me so it's been quite the learning experience going from the car into the home.