View Full Version : Paragon XXL
08-20-2006, 07:26 AM
Now they are ready.
It is a three way full horn assembly. It consists of 4 horns with a 15 inch woofers each, two tractrix horns with a 6 inch cone driver combined with a HF horn. The deviding frequencies are 500 Hz and 4000 Hz, overall efficiency is more than 100dB/1watt/1m. The width is more than 4 meters, the height 1,56 meters and the weight more than 400 kg.
Hope you like to see it.
08-20-2006, 07:28 AM
There are two bass horns left and right each, because one horn with a 15 inch speaker - which would have been sufficient - would have been too long and too heavy. The horn mouth is calculated for standing close to a wall, but not in a corner. For bass and medium band there are used low Q cone drivers. Closely compared with the Paragon you need only two of the bass horns, because the above system was planned for left-right usage. Nevertheless the horn mouth is much bigger. The woofer works on a compression chamber, which helps flattening frequency response. Although there is no phase plug, the horn guide is in such a way that as much as possible higher tones are reflected to the mouth, which helps to get the desired upper frequency limit of 500 Hz. A simulation with HORNRESP by David McBean showed to reduce the back chamber. A 35 liter chamber has given the predicted smoothened frequency response and a slightly deeper bass limit.
The tractrix form has only ben chosen for educational reasons which gives the desired directivity. It is equipped with an 6 inch low Q driver. The tractrix horn and (one) bass horn have the same width, which helps smoothening frequency response regardless of direction.
It sounds great! Yes I know, all builders have the best speakers of all ;-) Detailed measurement are intended for the future.
This high efficiency system distributes the sound with ease. There is no horny sound and I detected no obvious resonances or dips so far. - There was played some music from CD and a real drummer accompanied - the drumset was not too loud, really. - We had a live band at school, they made good music. But with the standard equipment their music sounded just as preserved. A CD track with Glenn Millers music recorded by the BBC played by the horn system sounded like live music. - The Who "Live at Leeds" made fun as well, the Who seemed to be present :-)
On the picture you see the ParagonXXL on the right of the stage. The stage itself was occupied by musicians. For better sound distribution I made a reflector like that of the paragon - I had tried it out at home with two small boxes - it worked. It was amazing to hear the sound all over the room independend of possition. Nomally large areas of glass and concrete make sound reinforcement difficulty in this audience, but for the sound reflector they did well.
08-20-2006, 07:35 AM
The above photo is not really good, some drawings will help for a better overview. The design of the bass horn is originally from E.G.Beck: http://www.egbeck.de/15bhorn0.htm
You are quite mad of course!
In the immortal words of Henry Frankenstein:
"Crazy, am I? We'll see whether I'm crazy or not."
"Look! It's moving. It's alive. It's alive... It's alive, it's moving, it's alive, it's alive, it's alive, it's alive, IT'S ALIVE!"
Don't let it get out of control!
08-27-2006, 01:42 PM
your writing made me laugh.
"You are quite mad of course"
may be ..., first it was not planned in this way but after some sponsoring I made a kick down for the project, the pupils liked it.
"Look! It's moving. It's alive ... it's moving"
I wonder wether the pupils were always confident, there was a lot of work, but finally they heard the result which convinced them. Glen, I do not want to follow your comparison too closely, I feel neither like Frankenstein nor Fritz . I take it with a smile and put the questions for body and brain.
08-27-2006, 01:53 PM
A full horn system must be big, the laws of physics can't be bent. In Germany there was a great time of cinema before WWII. The picture shows a horn combination "Euronor" by the company KLANGFILM, established by AEG and SIEMENS. The photo was taken around 1943 - 45 in the cinema "Röda Kvarn" in Stockholm, Sweden.
I wonder how many listend to Zarah Leander with this combination at that time?
But for us this old "dinosaur" was impractical. It had to be smaller.
08-27-2006, 02:01 PM
One of the first horn systems which delivered sufficient bass and low distortion was the Fletcher System by Bell Labs in 1934. A detailed description you can find here
Although it never came into production, it was a milestone for cinema sound reproduction. You can regard it as a predecessor of the Shearer horn system. Details are close here http://audioheritage.org/html/profiles/lmco/shearer.htm
08-27-2006, 02:07 PM
The Paragon seems to be comparable small. It might be desirable to smoothen bass frequency response, to overcome the problematic 500 Hz region and find a better tweeter solution.
An important aspect for me was to show the pupils that good craftmanship comes to a design which fullfills its goal for many years.
To come to a synthesis I was not willing to do any restauration or resuscitation. Details I've discussed above.
08-27-2006, 04:31 PM
How many (if any) of those Klangfilm "Euronor" speakers have survived ?
Wonder what it sounded like.........
Thanks for the great pictures !
08-28-2006, 01:21 AM
I just love this Historical stuff!!! That is one class project that I would like to have taken a part in. Looks dreamy. Thank you for taking the time to share all the info with us. I'll bet it sounds great.
04-26-2009, 03:39 PM
The horn California fits with a variety of speakers.
Frequency range shown for 0,5Pi and 2Pi (corner placement and free on the ground).
04-26-2009, 04:27 PM
I enjoyed the reading!
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