Welcome, Guest. Please Login or Register
Decware Audio Forums
12/18/14 at 07:23:38


Pages: 1
Send Topic Print
Imperial Hyperbolic Folded Horn (free standing (Read 4717 times)
gexter
Ex Member



Imperial Hyperbolic Folded Horn (free standing
08/25/05 at 06:08:45
 
Does anyone know anything about or built the Imperial free standing Hyperbolic Folded Horn?

It is described as jensen Imperial low-frequncy folded horn.
Does that mean it goes lower than the standard imperial or the decware Imperial?

Anyone have any specs on it? I found this design interesting.
I am pretty sure you hardcore Imperialists know about it but has anyone tried it?

thanks, Gex
Back to top
 
« Last Edit: 08/26/05 at 12:39:08 by gexter »  
  IP Logged
JohnF
Ex Member



Re: Imperial Hyperbolic Folded Horn (free standing
Reply #1 - 08/26/05 at 15:15:11
 
Gex,

I'm not sure which cab you are talking about.  I know of 2 cabs that Jensen called the imperial.  The one usually discussed here was designed for in wall installation.  The other cab was smaller, but designed for a corner, so probably about the same response.
Back to top
 
 
  IP Logged
gexter
Ex Member



Re: Imperial Hyperbolic Folded Horn (free standing
Reply #2 - 08/26/05 at 15:57:46
 
Sorry John, I did not mention that is was a corner cab. thanks for the reply!
Read your post in the speaker thread on what would you buy.
Interesting! Went to look up some of that stuff.
Back to top
 
 
  IP Logged
footstony
Ex Member



Re: Imperial Hyperbolic Folded Horn (free standing
Reply #3 - 08/29/05 at 03:20:03
 
HI Gexter,

some articles here you may have already seen.

1954 Audio magazine has some info re. the design of the both types. I think both types should sound similar. just different horn mouth.

1952 Technical Bulletin No.1 is the older design.

Jensen DIY designs show both new(er) designs

the geocities site has download limits so try the next day if you have problems

Regards Philip
Back to top
 
 
  IP Logged
footstony
Ex Member



Re: Imperial Hyperbolic Folded Horn (free standing
Reply #4 - 09/01/05 at 00:26:01
 
WHOOPS
maybe I should have put the link in for the above articles!

http://au.geocities.com/footstony/

Regards Philip
Back to top
 
 
  IP Logged
gexter
Ex Member



Re: Imperial Hyperbolic Folded Horn (free standing
Reply #5 - 09/01/05 at 04:51:35
 
thanks footstony, been there before and found it again through a search because the forum takes so long to go through.
This time I saved the info.
I think My Imperial data is bigger than any of my other single sub or speaker folder.
Now I am talking about a bigger house which my wife has been wanting for a long time because the kids need more room. I need it so I can build a fullrange Imperial.
two months ago I would have thought I was nuts. Now I know I am Cry

I wanna have a crack at a build in or a corner cab in a SO design.
Back to top
 
« Last Edit: 09/02/05 at 06:23:00 by gexter »  
  IP Logged
gexter
Ex Member



Re: Imperial Hyperbolic Folded Horn (free standing
Reply #6 - 09/03/05 at 06:38:21
 
DirtDawg as far as "Black Cloud" - ish no worries I understand, life is very interesting at times to put it mildly. Thanks for identifying, you know, the" you are not alone thing". Anyway enough of that.

The Imp sub corner cab will have MDF internals w/ bracing not found in the jensen design, it will resemble the bracing behind the driver in the decware built in Imperial.
the rough triangle enclosure that holds the driver will be one complete unit that will fit into the corner cab enclosure, so it will also be an 1 1/2 narrower inside. Access will be from the front, a removable faceplate will cover the driver.

I tend to overbuild when I build stuff. PC's to framing, but thanks for letting me know that the corner cabs have vibration issues, that changes things a little.
I wanted to go light in the design but  is not turning out that way.
After playing around, you can't do a decware Imperial SO hack all with heavy cardboard and I can't afford to do my styro panels so hybrid it is.

thanks to stvcmty for some of the tips in carboard bonding.  I also put all the steel plates from my dusty weight set to good use. I am sure they are heavier than when I was in my thirties.


My wife noticed all the carboard in my car on my way to work this weekend and is starting to put things together, but I worked like a dog this week to get her projects done so not a word was said.
When I go home from work on monday morning for a couple hours I hope to have all the cardboard sections done in rough dimensions.
the Mdf part will take much longer to pull off

Later, Gex
Back to top
 
« Last Edit: 09/05/05 at 05:43:35 by gexter »  
  IP Logged
serenechaos
Ex Member



Re: Imperial Hyperbolic Folded Horn (free standing
Reply #7 - 09/03/05 at 13:38:48
 
Gex,
So what will the low frequency cut off be?  
(Mouth size).  
Are you changing the compression chamber volume?
or the flare rate?
length?  

Expiring minds want to know...
Robert  :)
Back to top
 
 
  IP Logged
gexter
Ex Member



Re: Imperial Hyperbolic Folded Horn (free standing
Reply #8 - 09/03/05 at 15:29:38
 
So far it is an exact copy in size. The only sustantial Mod is going to be the compression chamber and the added slot.
If you know what the corner horn looks like, my mod has one big chamber

I would like to lower the horn frequency from around 35 to 20 but I still don't know the effects the altered chamber, horn entry and slot will do.
The horn could be changed later because it is going to be cardboard at this point.


Another Question--- Sometimes I have used the sum of two channels in a car stereo to create a single channel. The pos of one and the neg of the other and a resister to adjust the Ohms.
Has anyone tried this with a reciever? At the moment that is how I am going to power the sub while I play with it in my garage. The receiver can drive four Ohms.
my speakers will be 8 and the sub 4 Ohms (about)



Later ,gex
Back to top
 
« Last Edit: 09/08/05 at 04:08:37 by gexter »  
  IP Logged
gexter
Ex Member



Re: Imperial Hyperbolic Folded Horn (free standing
Reply #9 - 09/08/05 at 04:08:59
 
Anyone?
Back to top
 
 
  IP Logged
DirtDawg
Ex Member



Re: Imperial Hyperbolic Folded Horn (free standing
Reply #10 - 09/08/05 at 10:50:03
 
gexter,
I have only goofed around with a "home" unit once and it really got hot trying to run it mono. With most of the Pro stuff I have it's simple because they are designed to use balanced lines or 3 wire connections. 1 wire is (+) signal, another is (-) return (or reference) signal, and the third is a ground/shield. To get Mono you simply put the (+) signal in one channel, the (-) reference signal in the other and connect your speakers between the red (+) outs. One thing to keep in mind is that the output impedance is doubled so that an 8ohm amplifier in mono mode becomes a 16ohm amplifier.

One of my older amps has 300W/channel @ 8ohms, but at 2.5ohms it has circuitry to limit current to protect the output transistors. When used in mono with an 8ohm load you get (optimistically)1200W, but with 4ohm load you get 100W, because the amp is protecting itself from high current overload. Point is you may not gain anything by using mono.
Back to top
 
« Last Edit: 09/08/05 at 10:52:11 by DirtDawg »  
  IP Logged
gexter
Ex Member



Re: Imperial Hyperbolic Folded Horn (free standing
Reply #11 - 10/01/05 at 11:04:29
 
Modified corner cab done.
Not really a corner cab anymore. Redesigned to fit under my workbench in my garage. it will fire into the space where my air compressor is.
See " Imperial corner  So kinda so" for details and a Pic.

Gex
Back to top
 
« Last Edit: 10/01/05 at 11:12:35 by gexter »  
  IP Logged
Pages: 1
Send Topic Print