Old School Horn vs Modern Vented Box

[winslow]

I always wanted a Cyclone and the other one they never brought out...what was the name of it? It had the 15" cones connected to a servo like you did for the Servodrive subs. Maybe Vortex?

 

[royalwe]

Was looking for a picture of the old tonka sound speakers...

Tonka Sound was well represented at the raves I used to go to in the 90s. Here's a pic of some of their cabinets, with their distinctive yellow paint.

I don't know if the Tonka boxes are DIY, or if they just bought someone else's cabinets and painted them. The tops are JBL, so the subs may be JBL too.



Here's the response of the Cerwin Vega EL-36c as a front loaded horn, *and* as a back loaded horn.
So we see that the Tonka setup - a back loaded horn - makes one big difference. It fills in the low frequency hole.

I know that Danley invented tapped horns based on a similar logic. Basically Danley noticed that you could fill in the low frequency hole on a horn that's too small by using the energy radiated from the back on the cone.


Here's the excursion of the CV, as a back loaded horn and as a front loaded horn. The curve is basically identical, but you absolutely positively have to use a high pass filter with a Tonka-type sub, because the woofer is basically flapping in the wind below 40hz.

So Tonka is doing something similar to the tapped horn here. Of course in 1995 we didn't have software to simulate this stuff, so it may have been trial and error, a happy accident. Or this might be a commercial sub that's painted yellow.

I can't tell what the answer is, but that arrangement looks quite awesome for an efficient low frequency sub that doesn't need much EQ. (You could probably flatten out the response on the Cerwin Vega, but that would require EQ and a mic, and a lot of these 90s raves were rushed affairs; no time to EQ the room really.)

Resurrecting this thread from the dead but if some of the older posters are around and interested, I used to set up speakers for Tonka as a side job while I was in college. All drivers were JBL. The tops were JBL pro sound and we ran them from around 120hz or so up.



Those scoops were based off some older JBL design but were built by someone else, they used JBL professional drivers. They really did best in the mid-bass and we would run doubled up earthquakes under each one crossed at 80 at the bigger events to handle the low end.