horns - diyAudio
Go Back   Home > Forums > Loudspeakers > Multi-Way

Multi-Way Conventional loudspeakers with crossovers

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 24th July 2004, 12:18 AM   #1
Shpoop is offline Shpoop  United States
diyAudio Member
 
Join Date: Jul 2004
Location: Florida
Default horns

ok...so first off, what frequencies are horns generally effective at? like if i attached one to a full range driver, would that pretty much kill it as a full range?

also, can you put curves in between the speaker and the horn?...and on the same idea, can you but pipes or something inbetween the horn and teh speaker, if they arent curved? my intuition says no, but id rather ask the experts. If my wording was difficult to understand, just tell me and ill try again
  Reply With Quote
Old 24th July 2004, 06:22 AM   #2
diyAudio Member
 
Nappylady's Avatar
 
Join Date: Feb 2003
Location: Salt Lake City
Send a message via ICQ to Nappylady Send a message via AIM to Nappylady Send a message via MSN to Nappylady Send a message via Yahoo to Nappylady
Read about horns. Read about horn theory. It's really not that complicated.

A horn is an acoustical impedance matching transformer.

Speaker cones have very high acoustical impedance compared with the air; it's very easy for the speaker to push on the air, but not vice versa. When the cone does push on the air, huge amounts of energy are wasted because the cone has so little mass to push against.

A horn works because (basically) all the air inside the horn becomes coupled directly to the speaker cone--the cone, then, is acting on a much larger amount of air, so the impedance mismatch is greatly, greatly reduced.

As with ordinary boxes, Hoffman's iron law rules: you can have a box that is small, loud, deep. Choose any two, at the expense of the third.

While most horns are designed and used for treble reproduction, the theory can be applied to any scale--there are basshorns out there that play down to 10hz. The one that comes to mind is actually someone's basement. (No, I did not mean to type "in someone's basement". The horn *is* their basement.)

What have you got in mind? Let's build something :-)
  Reply With Quote
Old 24th July 2004, 06:55 AM   #3
TheoM is offline TheoM  United States
diyAudio Member
 
Join Date: Mar 2003
Location: Ohio
Default The Horn *is*....

This is the sort of thing that gets my deepest respect. I'm really interested in the "out there" ideas.

********he guy who made a sealed cab from a huge concrete casting. (wish I had the link).

The 25 driver per side line array

10 foot high sonotube subs

the servo subs that according to urban legend killed a guy.

Are there more? Its my ambition to do something like this.

Could I make a horn from a geological formation like a cave entrance?

There's art here... somewhere.... Any ideas out there?
  Reply With Quote
Old 24th July 2004, 03:50 PM   #4
diyAudio Member
 
paulspencer's Avatar
 
Join Date: Sep 2003
Location: Melbourne, Australia
Shpoop,

Horns can cover the full audio bandwidth BUT each horn has a limited bandwidth. Some use something like an Oris horn with a full range driver which will go down to about 300 Hz I think. Below this approx range the horn gets quick large and it becomes necessary usually to change strategy. You might add a bass horn. You might use some very large high efficiency PA drivers to cover the midbass up to 300 Hz. A good horn system is likely to be 3 way or 4 way.

Have a look around at some horn systems before you build anything to get an idea ...

Adrian Mack horns

architectural horns example

Oris horns

Some comercial horn examples

John Sheerin's horn website

Lab Horn

Royal devices huge basement horn

Ultra fi horns page

There's some food for thought

You might also search this forum a little, you willl find quite a few horn projects. Magnetar has done a lot of horns ...
  Reply With Quote
Old 24th July 2004, 05:52 PM   #5
Shpoop is offline Shpoop  United States
diyAudio Member
 
Join Date: Jul 2004
Location: Florida
well attached is what i originally had in mind for a full range unit...so perhaps my most important question still stands...can u lengthen the pipe between teh horn and speaker with minimal negative effects?

beautiful art, eh?
Attached Images
File Type: jpg untitled1.jpg (20.9 KB, 169 views)
  Reply With Quote
Old 24th July 2004, 06:16 PM   #6
diyAudio Member
 
paulspencer's Avatar
 
Join Date: Sep 2003
Location: Melbourne, Australia
I don't understand that pic and what it shows!

It looks like a tweeter attached to a vent then a tiny horn in the middle of a W frame dipole woofer!!!!!

I'm also not sure what it is you are trying to achieve, which makes it hard to give a reply! When you say "can I do X?" the question remains "what are you trying to achieve?"
  Reply With Quote
Old 24th July 2004, 06:56 PM   #7
Shpoop is offline Shpoop  United States
diyAudio Member
 
Join Date: Jul 2004
Location: Florida
haha excuse my crappy paint skills...but you are right, its a horn in the middle of a W frame dipole sub...the first pic is simply a front view, the second is an overhead

the speaker for the horn would need to be further back, so that the sub has some room to breathe, hence the extension

im just toying with full range designs is all, wondering what can be done
  Reply With Quote
Old 24th July 2004, 07:16 PM   #8
GM is offline GM  United States
diyAudio Member
 
GM's Avatar
 
Join Date: Jun 2003
Location: Chamblee, Ga.
>can u lengthen the pipe between teh horn and speaker with minimal negative effects?
====
The answer is a resounding NO for what's depicted. With FR drivers you want to limit the compression ratio to < ~2:1, with little/no reactance annulling section since a FR driver's flexible diaphragm construction doesn't lend itself to doing much in the way of annulling.

WRT to putting curves between the horn/driver, if you mean have different flare rates at different points along the horn's expansion, such as starting off with a 50Hz flare for some distance then switching to a 100Hz, etc.; then , yes, you can do it, but unless you know what you're doing I don't recommend it. Indeed, some of the better FR backhorn designs have multiple flare rates.

Front horn versions are CD type horns, trading pattern control for flat response/HF extension, so some EQ is required. For FR drivers it's best to use just one or two low gain flare rate(s) to keep distortion low/HF attenuation minimal.

GM
__________________
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
  Reply With Quote
Old 24th July 2004, 07:17 PM   #9
diyAudio Member
 
Join Date: May 2004
Location: San Francisco
Send a message via AIM to joe carrow
Quote:
Originally posted by Shpoop
haha excuse my crappy paint skills...but you are right, its a horn in the middle of a W frame dipole sub...the first pic is simply a front view, the second is an overhead

the speaker for the horn would need to be further back, so that the sub has some room to breathe, hence the extension

im just toying with full range designs is all, wondering what can be done

I don't think that it will work as you have drawn it, not the way I understand your description. Are you proposing to run a pipe as an extension from the horn mouth to the driver? In a full range configuration, I would expect all sorts of coloration of the sound from pipe resonances and stuff. Like yelling through a tube.

If you use the links above, you'll probably learn about how a horn has to be shaped, and how some horns would have a long section that's nearly straight before it flares out- and you'll see that there are trade-offs. I think that a long tubelike section like that could work for a bass horn, but probably not for higher frequencies.
  Reply With Quote
Old 24th July 2004, 07:57 PM   #10
diyAudio Member
 
paulspencer's Avatar
 
Join Date: Sep 2003
Location: Melbourne, Australia
It pays to understand firstly what you want to achieve and the strengths and weaknesses of different designs.

To put a dipole woofer with a front loaded full range driver horn - this would make it difficult for the dipole to keep up - a lot of displacement would be needed. There is no reason to try to interweave them together. The horn can sit on top, and it wouldn't fit inside the dipole.

Nothing wrong with this approach, but it might help to look first at what people conventionally do and to understand it. Innovation usually comes from those who understand convention, then push the envelope one step further ...

You might look into rear loaded full range horns. ie use a full range driver that doesn't have much bass. You then horn load the rear of the driver to bring the efficiency of the bass to match the rest and then you get a full range response. The bass will normally only go down to 50 Hz but some like this approach.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
smith horns and using compression horns for a Karlson party speaker project bikehorn Multi-Way 14 30th January 2013 06:20 PM
horns jzeleznik Multi-Way 2 5th March 2009 08:25 PM
T-Horns layertone Full Range 21 28th October 2005 09:17 PM
SPL of Horns Kofi Annan Multi-Way 12 2nd August 2004 03:20 AM
Horns: Vibrations and resonances in metal horns Rocky Multi-Way 10 28th July 2004 02:38 AM


New To Site? Need Help?

All times are GMT. The time now is 02:22 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2