Right!
Since building that "NVA Inside" amplifier with souped up power supply, I've had some great sounds in my room over the past week.
It got me asking a basic question about my room flooders: why are you persisting on using damping inside the cabinets?
Whilst visiting Hull with them a few weeks ago, myself and a speaker designing mate of mine, were trying to make our minds up as to what I had actually built, concerning the cabinet itself. Was it a transmission line or was it a horn? Up to that moment, I'd always thought I had built an expanding transmission line cabinet.
The conversation went something like this:
Transmission lines work on the progressive absorbtion of the rear radiation of a lousdpeaker cone and normally get narrower, the further away they get from the driver. You can have one that expands, or can you? Now a the horn gets wider, the further away from the driver it gets. Horns are not damped, transmission lines are, and need to be in order to work as they are supposed to.
Now my flooders get wider as they go towards the exit, which is blocked, except for a port that loads the driver, so are they horns? Not if the mouth is blocked. Yes but they expand like a horn does, so just because the mouth is blocked up, that doesn't make them "not" horns does it?
Well the driver is mounted half way along said horn, so they are quarter wave expanding resonators or something?
We went on for a while and eventually decided that a decision had to be made on what these bloody things actually are.
What a load of graph waving theoretical
![Bollocks :Bllocks:](./images/smilies/obscene/bollocks.gif)
I hear you say and feck all to do with music.
BUT..... deciding what I had got here was quite an important process, as to damp, or not to damp, depended on the outcome of the "transmission line or horn" question. We can all take the damping out of our boxes and steel line them, but transmission lines don't work like that; they need progressive damping, so in my case the distinction is important.
So....I decided to remove complexity and say that they are horns, but terminated by a port, because they expand towards the exit. Horns expand, transmission lines contract, simple as that, my lines expand, therefore horn...end of.
Transmission lines, you damp them, horns, you don't, so why do my cabinets have stuffing in them, now I've decided they are horns?
So let's go with the "they are some kind of horn" theory and un-damp the buggers then.
A quick session with screwdriver, remove the bass/mid unit and yank out the stuffing and......yep....they are definitely some kind of horn hybrid. Awesome!
What a difference! Combined with the "NVA Inside" amplifier, these flooders sing their little hearts out. Even more music, even less hi-fi
I love it when a question gets answered like this.
My Burhoe/Allison/Dunn/Steve/ omnis, are horn hybrids, not transmission line hybrids
![Dance :dance:](./images/smilies/eusa/dance.gif)
Somebody’s telling me the latest scandals.
Somebody’s stepping on my plastic sandals. Joe Jackson (1979)