EA: How So Small With Extended Low End

[Depth Charge]

Hi everyone!

There's something which has been puzzling me for many years. Euphonic Audio make bass guitar amplifiers and speaker cabs. Their cabs are transmission line designs which are small, efficient and produce deep, extended bass (I once had a shot of their 1x10" coaxial bass combo and can attest to their bass extension).

http://www.eaamps.com/2005/products/cxl112l.htm

For example, here are some of the specs for the CXL112:
19"H x 17"W x 15"D
103dB @ 1m
38Hz to 14kHz

My question is; how do they do it? I'm not sure if the fact that they use TLs helps explain this or make it even more inconceivable. Anyone up for discussing this?

[sreten]

Hmmm........

Transmission line cabinets can be designed to have a smoother and more extended low
frequency output than a corresponding vented enclosure given the same internal volume.

Only true if the box is too big for proper vented in the first place......

/sreten.

[Depth Charge]

Wow!....

Did I miss a post? Where did that quote come from Sreten?

[pinkmouse]

They are probably tuned to about 60-80Hz, to give you that "punch in the chest" feeling, rather than real low extension.

[Depth Charge]

Hi Pinkmouse.

I have to say that I really don't think that's it. I played my bass through the 1x10" combo with a 1x10" extension cab attached and it sounded way deeper and more solid than (probably) any other cab I'd ever heard. Certainly more so than my previous amp witch had a 15" driver tuned to 40Hz. It wasn't boomy in the slightest.

[sreten]

Originally posted by Depth Charge
Wow!....
Did I miss a post? Where did that quote come from Sreten?

http://www.eaamps.com/2005/technolog...ssion_line.htm

/sreten.

[Depth Charge]

Ah....of course. You've got to love the guy with the beard!

Now maybe I got the wrong end of the stick, but I was always under the impression that once you started using 8" and 10" drivers and beyond for your transmission lines, the cabinets started to get really really big and that was true for low efficiency hi-fi drivers as well as pro drivers. If that's true, how do they make them so small?

Maybe I should just buy one, measure it and take it apart to see how it's made. Although it would defeat the purpose of figuring out how they're made so that I can make something similar but cheaper because I can't afford their products in the first place.....

[sreten]

Hi,

You cannot break the laws of physics in an enclosure.

19"H x 17"W x 15"D.......... large for a 1x12" cabinet
103dB @ 1m...................... yeah right......
38Hz to 14kHz................... possibly

/sreten.

[planet10]

That box is almost for sure an aperiodic box, with a partition in it to create a short heavily tapered line... anyone seen a picture of the back?

dave

[Depth Charge]

Hey Dave,

If you're talking about the back of the CXL112, no I haven't. There is a 'vent' at the bottom on the front and I'm reasonably sure that the back just has the connection terminals and L-pad and nothing else.

I'm interested that you think it may be an aperiodic enclosure, mostly because I know so little about them. Can they be modeled in Martin King's Mathcad sheets by increasing the stuffing density and so fourth?

Cheers,

Steve.