Amplifier for subwoofer

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Hi,

I built a system stereo subwoofer where the woofer function as both a subwoofer and a woofer. I used a 7" wavecor subwoofer driver (sealed enclosure) and crossed it at about 100~ 200 Hz. However there is no punch to the bass. It goes low but it doen't do the normal bass job well.

I drove it with a sure electronics tripath amp class t. I suspect it has something to do with me just using a normal type of amp. Subwoofers such as Velodyne used some sort of sensing circuit etc that helps it perform better.

So my question is, are there special amps (non conventional) out there that can drive subwoofers a bit better. For example maybe a transimpedance amplifier ( to counter act the inductance at fs), any thoughts or experience on this matter will be greatly appreciated.

Oon
 
How are you using it? Did you hook up the rest of the speakers as well? If you only use the sub, you won't get any punch. I discovered this one time when I was testing a sub. I didn't feel any punch. Then I hooked up a mid and a tweeter and all the "punch" was there.

Keep in mind that there are sub woofers, woofers, midbass, midranges, and tweeters for a reason. A true sub is always less than 100Hz and it's hard for it to go higher than that. Woofers on the other hand go a little higher, and it's hard to make them go below, say, 80Hz. Even harder if you're using 7 inch drivers.

Finally, a sealed enclosure makes things even harder. That's why folks here build exotic things like infinite baffles and tapped horns.
 
I used this model.

SW178WA01

Since it has a frequency response way above 3KHz, I think it should be okay.

The other factor is the possibly the sub woofers are designed in a different way than woofers (maybe damping), and hence they don't give that punchy sound.

I let it cross at about somewhere between 100~ 200 Hz, was planning on using it as a normal woofer. I have a fullranger to cover between 200Hz onwards...

Oon
 
The other factor is the possibly the sub woofers are designed in a different way than woofers (maybe damping), and hence they don't give that punchy sound.

Could be, but keep in mind that a sealed box will usually give you a flat response (that's why "sound quality" fans prefer them). "Punchy" boxes, like the ones in cars, are tuned at a high frequency. Car audio is all about punch, because you don't need sub ("room gain" in a car is huge for sub-bass so it makes it easy to go really low, you just worry about the punch).

I guess you already tried different room placements, right? My sub gives an interesting amount of "punch" (not really punch, but more like "tighter" bass) in some areas of my room. Of course that means it sounds great away from my favorite listening position: my bed.

Finally, don't forget equalization. Sometimes a speaker can sound "weird" because it's not well EQ'd. Sometimes you can turn down a specific frequency that's making it appear loud (room modes), and crank the volume up a bit.

This also depends on what kind of material you're listening to. My last sub goes from 35 to 75Hz. It sounds AWFUL with techno music, but it's great for movies and video games.
 
Hi HJF,

I am intrigue by this topic because I notice many subwoofer manufactureres claim some special design for their amp. I suspect that one of the reasons my sub lacks punch when I used it as a woofer is the the charateristic of the driver itself.

For example, these two wavecors speakers one is a mid woofer, one is a subwoofer (aboutt he same size).

The sub has a impedance that goes to 300ohms at Fs,

SW178WA01

Whereas the mid woofer only goes to 100 ohms at Fs,

WF168WA01_02

High inductance may prevent current from flowing, and hence creates the slow feeling....

I will start another thread called transconductance amplifier for subwoofers, see if it makes a difference...

Oon
 
However there is no punch to the bass. It goes low but it doen't do the normal bass job well.

........
Oon

Hi,

I found these statements contradictory. A subwoofer is designed to go low.

What size sealed cabinet did you use?
When you say there's no punch, do you mean you can't physically feel it, or just in terms of the sound?

What's it crossed over to, and have you tried reversing the phase to ensure it's integrated properly?
 
Sorry for the late reply. Life has been busy.

I am familiar with class d, already using it. What I meant was, if you looked up velodyne, related etc they always claimed some proprietary amplifier system. There was even a subwoofer system that has a accelerator meter built into the speaker.

One thing I might not have very clear is I am using it with satellites, so the crossover point is quite high, about 200hz.

The sub dooesn't seem to do a good job of drums (normal woofer stuff) etc, but the ground shaking stuff, it is okay ( home theater stuff)

Oon
 
Not sure if this has been mentioned, Just wanted to help. The problem might be the enclosure you have it in. Sealed enclosures are meant for people who want a clean sound with good quality from their Subs. If you want more punch, you could probably use an amp to give it some more kick, or build a new box that is ported. Ported boxes give the driver more air intake, alowing it to get the "Punch" That your looking for.
I hope this was helpful.
 
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