Scoop Icons - RX18 & S118

Tony, obviously you're not gonna publish the plans for these, but these are iconic boxes, with nothing quite as good before or after them.

Was wondering how you arrived at the designs in terms of prototyping, and acheived pretty much perfect compression ratio/horn length for PD1850?

Bet it wasn't a computer

What A question. Nick, your right about the computer, I didn't own one in those days, did anyone?
I don't mind spilling the beans on this one because I have spoken about it before.
My Introduction to the "Scoop" back in the '70's was via the JBL 4530 and the 4520. JBL plans have always been available for these, and I had already started to build them for the early Discos. One day, I came across a cab that seemed to have had an 18 squeezed into it. I remember it being a very shallow cab, and I knew straight away that this wasn't the way forward. So I had a think about it and decided to set about building a new one in the only logical way I could think of at the time. Because there is three inches difference between the 15 an 18, I decided to scale everything up by the same amount. ( high Tech ). I have always drawn horn cabs full size on a board, so that I can the see the expansion rates. I have always had this vision of wave form and defraction stuck in my head since the beginning, so it's the only way I can work.
So, basically, that was the cab, except all the panels were now bigger. More power was also being used than would have been used to power the JBL's back in old days of film. 40 watts probably covered it in those days.
The first cabs I ever made in my Garage were 2x12 and 4x12 guitar cabs. Because I had no machinery, these were put together using 2"x2" frame work. These were heavy cabs, but produced a very strong solid sound. I soon discovered that mass played an important part in good sound.
I wasn't the first to make an 18"scoop, but those that had been made were flimsy with no bracing in the lower horn mouth. The top part of the scoop is self bracing, but the exposed panels at the end of the horn were left to flap about in the breeze.
I still maintain that within reason, most scoop bins should sound very similar, but differ because of the type of build. Single 18mm braces are not enough to stop panel resonance, thats why all my braces are 36mm. I also notice that a lot of holes are creeping into braces these days. For me this is a no no. I can't see the point of trying to strengthen something with a brace and then remove material which make thinner sections which would help the brace to resonate. I understand why people do this, and I do like to see a pretty box, but form over function is not the way when it comes to sound.
Getting back to the 1850 situation. The good combination is purely coincidental, because the S118 was alive and kicking long before the birth of the 1850. I remember seeing the PD speakers for the first time on the Turbo stand one year and knew then that I must have them. Before these came along it was Gauss.
So there it is, no smoke, no mirrors just lots of plywood.
As a matter of interest, my new 4 way system is almost complete now, details will follow shortly. The only light features are the components which are all Neo. I've even designed a new hf horn for the system.
I hope I've been clear regarding the "scoop"

Interesting...so about the mouth braces... it's better one thicker braces then 2 braces? I mean instead of a thick cross something like this # ?

levyte357 wrote: Tony, obviously you're not gonna publish the plans for these, but these are iconic boxes, with nothing quite as good before or after them.

Was wondering how you arrived at the designs in terms of prototyping, and achieved pretty much perfect compression ratio/horn length for PD1850?

you been taking 'E' tablets Lev? smiley36
listen out for a clash that's happening tonight smiley2
a young SP member is about to upset a few people

Bitzo, I'm not saying that one thick brace is better than two thin ones. I'm saying two thick braces are better than two thin ones.

mykey- wrote:

levyte357 wrote: Tony, obviously you're not gonna publish the plans for these, but these are iconic boxes, with nothing quite as good before or after them.

Was wondering how you arrived at the designs in terms of prototyping, and achieved pretty much perfect compression ratio/horn length for PD1850?

you been taking 'E' tablets Lev? smiley36
listen out for a clash that's happening tonight smiley2
a young SP member is about to upset a few people

Proof is in the pudding...

S118+PD1850 has been weapon of choice for many soundsystems for over a decade..

Closest scoop in SPL I have heard is SteveB scoop.

When systems clash with Cows vs S11850s, occurs, then we can talk.

Don't really see the point of Scoop shootouts anymore, as people want the scoops tested & measured, in a way that is nothing like a real clash.

not had any good feedback about steve b's scoops I'm afraid, and I've heard the JBL ASS scoops many times

mykey- wrote: not had any good feedback about steve b's scoops I'm afraid, and I've heard the JBL ASS scoops many times

You have, you just didn't know it... :lol:

Who do you think built the scoops for Rensaab (APS System), Paulus (Trendsetter), I-Spy, Word Sound Power (WSP), and scoops for many other systems in the UK? smiley20

Don't forget it was Ren's System that Robert Newsham said sounded fantastic, and he couldn't believe how much sub he was getting from only 8x cabs.

There is another sound system from High Wycombe called "Justified Love", who you will also be hearing about soon with SteveB scoops. One of Ren's mates...

Lots of scoop talk then, must be coming up to carnival. I still think the main difference in performance is due more to build quality than anything else. I say this because I can't believe that an inch here and an inch there in a change of design will make a difference to wave lengths that are 20-30 feet long. In general you will find that most of the good sounding scoops are the heaviest and the most solid. As time goes on, more and more scoops are looking like mine in terms of build.
I've never mentioned performance or how the RX18 compares to anything else, mainly because I'm not really bothered one way or the other. My intension is always to make the best cab. Whether I achieve this is another matter, but this should be everybody's intention. If things are done on the cheap, and a lot of times they are, it will result with question marks hanging over the cabs.
It takes three and a half sheets of 8x4 with no meaningful off cuts to do an RX18. How does this compare with anyone else's cutting sheet?