Driver for low volumes

[TechnoMage]

Is there anything special I should be looking for in a driver to be used at low volume? I'm building a sub for the office at work so I need to keep the volume down.

Thanks,
-Ron

 

[Lothar34]

I would think something fairly rigid with good control. Big voice coil, high Vas, high Qms and a low Xmax.

What size were you thinking about and what's your price range?

 

[TechnoMage]

I'm looking to go for something small, probably in the 8" range. I did have one thread going here but low volume wasn't answered.

Right now I've been thinking about going with the Tang Band W8-740C since I can fit this in a 5 liter box.

My only concern would be that it doesn't work well at low volumes.

 

[Lothar34]

I thought you were gonna get that Dayton?

 

[TechnoMage]

I had thought about it, and the Dayton does go a little lower but while the TB fit's in a 5 liter space I'd need 23 liters for the Dayton. I think that's to big for the space.

 

[Lothar34]

Here you go:
http://www.madisound.com/cgi-bin/index.cgi?cart_id=1994868.421&pid=1959

EDIT:
Well they recommend 15L for this one. Is that still too big?

 

[Lothar34]

Well that one is out of stock.

Either of these will be good too:
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=290-042
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=296-175

Did you need shielded or not?

 

[TechnoMage]

I don't need shielded since it will sit under my desk. The Audax requires to much space, even in a sealed unit. The Pioneer is better but still needs around 15 liters.

Maybe I'll build a couple of them to test things out. 🙂

 

[Lothar34]

I believe that's 15L with no stuffing. You can probably get away with 10L and some polyfil.

 

[TechnoMage]

Lothar34, thanks for the advice. Couple of questions. Not that I doubt you but why do I want a high Vas, high Qms and a low Xmax?

The Pioneer definitly wins the Vas and Xmax
2.440 ft cubed vs 1.130 ft cubed
2.88 mm vs 12.0 mm

But the Tangband wins the Qms
10.530 vs 4.170

I know I keep coming back to the Tangand but I love the idea of a 5 liter sub assuming it plays well at low volumes.

 

[Lothar34]

This is the way I understand, it so someone correct me if I'm wrong please:

The Vas and Qms have to do with the rigidity of the speaker and motor. Those along with the big voice coil combine for more control over the cone movement and more accurate reproduction and less loss from the motor trying to control the cone.

The Xmax comment was more just because you don't need it. If they're not getting much power then they're not going to be moving a whole lot.

(somebody please correct this for me)

 

[Cal Weldon]

The TB 740 is a heck of a driver for a steel basket unit. I don't know what it sounds like in a 5 litre though. Mine are bigger and use PR's.

 

[Lothar34]

The TB 740 is a heck of a driver for a steel basket unit. I don't know what it sounds like in a 5 litre though. Mine are bigger and use PR's.

How big? And how much weight on the PRs?

 

[Cal Weldon]

Oops, missed this one. The cabinet is about 1.25 ft^3 with two 8" drones. These are the pioneer units and I painted them with white glue a few times so I can't tell you the moving mass. I liked the sound so I didn't add more.

 

[Lothar34]

Thanks.

 

[SpeakerBob]

Small sub, low volumes sounds an ideal candidate for a Linkwitz transform type sub. I'd try a 15" driver in a 17" cube.

Cheers,

Rob.

Edit: oops! looks like you want more of a desktop type system. Disregard my post😱