Forums - Will the Imperial SQ work outside?

Getafix

Ex Member

Will the Imperial SQ work outside?
08/03/06 at 11:42:28

A quick background in what I'm trying to achieve. I looking to build a small high quality mobile PA that will run of alternative energy (probably solar/wind stored in a battery) to use at festivals. So to maximise power efficiency I want to use high efficiency speaker. Hence a horn is the only way forward in my opinion. I looked at many designs but the Imperial SQ is appealing. So I was thinking of doing was using two of the imperial SQ with a compression driver mounted on the top of each cabinet. I know the standard imperial is more recommended for PA but I not interested in the extreme SPL. I want the low bass with the authority only a horn can deliver.

From my understanding from reading the text the horn is acting more like a variable frequency resonator. Upon reading some text about a Velocity coupled resonators the conclusion was that resonators don't work well out side. What I want to know is does this apply to the Imperial SQ?

Thanks

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JimP

Ex Member

Re: Will the Imperial SQ work outside?
Reply #1 - 08/03/06 at 17:54:41

GetaFix,

I can't answer your question about the Imperial SO, but I think your assumption about the standard Imperial not having authority in the bass is off. Check out my post "Imperial PA". I highly doubt you would miss the 20-35 Hz range that the standard Imperial doesn't hit hard (there is output down there though!), especially in an open-air situation.

If effieciency is needed, the standard Imperial has a higher spl than the SO version also from what I read. You'll need 2-4x the power to reach the same spl, and the SO is only designed to go up to 100Hz (I think, maybe lower) so you would need essentially a full-range speaker to handle the rest. Not many mid-horns go that low.

Two imperials, each with a horn-mid/Tweeter is all you need. Hell, depending on how big a crowd you are playing to, one might be enough!

Of course this is my opinion based on my experience with the standard Imperial. I have no experience with the SO model so hopefully someone else can chime in and help with your question.

Good Luck,

Jim P

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Getafix

Ex Member

Re: Will the Imperial SQ work outside?
Reply #2 - 08/03/06 at 19:28:23

Thanks for the reply Jim. I think you might have miss read my previous post. I wasn't saying the imperial was not authoritive, quite the opposite, I imageion a horn of that size would make bass of great power. What I was stating is that i would like an enclosure that generate bass like a horn. The reason i was thinking about the SQ is because in my experiance, back loaded horns suffer a dip in response between 70-90 hertz where the horn is out of phase with the driver. Also PA back loaded hoens that i've herd don't seem to have the tightness and control that a front loaded horn has. May be the imperials don't act like this. Are you using your imperials as sub cabs if so what frequency are you crossing them over at. Any more input from your experiance with the imperials will be greatfully recieved.

You mention the SQ can only act as a sub cabinet but in steve's text about SQ he mention that with the right drive it can be used a full range cabinet. Higher frequencies emitting from the slot infront of the driver. I was looking at crossing it over at about 400-500hz to a mid compression driver, then crossing over to a high compression driver at 5-6Khz.

Thanks

Mark

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Valiant_ap6

Ex Member

Re: Will the Imperial SQ work outside?
Reply #3 - 08/14/06 at 00:41:26

Hiya Mark,
There seems to be alot of misunderstanding in regards to the Imperials when they are described as being a PA speaker, people immeadiately get visions (aural visions maybe?) of the abysmal sound quality thrown out by the flimsy boxes with the 'massive' 12" woofer and companion compression driver that predominate at sports halls and clubs.

The Imperial is not that kind of speaker.

I constructed two Imperials with twin 15" drivers. All the testing and playing was conducted outdoors. Partly because they are massive and location would be problematic, and also because I recognised that these beasts could and would cause damage to the house and its contents.

20 and 30 Htz test tones where hardly audible, but windows and steel roofs vibrated harshly in sympathy, and these tests where conducted with low power levels ie: <50 watts. The vibrations where felt in neighbouring houses.

My Imperials where built to a price and are limited by driver response, materials and workmanship, but still deliver rock hard bass, and acceptable midrange. Apparently proper driver selection can extend the mids and highs, deleting the need for add on mid/high range drivers.

I have no experience with SO Imperial, it is a specialised machine. Small? Imperials are not small. They are a whole lotta fun.

Cheers

Gary

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jj420 Ex Member	Re: Will the Imperial SQ work outside? Reply #4 - 08/15/06 at 20:43:28 The Imperial SO will perform as advertised in the great outdoors, its when you take it indoors that you run into problems, too small a room, and all they do is flap because the waves from the horn cant propagate. Build 'em
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morpheous85 Ex Member	Re: Will the Imperial SQ work outside? Reply #5 - 08/21/06 at 04:25:53 Ok, I believe he's talking about the full range Imperial, which he is referring to as the SQ (Es Que). Not the SO (Es Oh). Jason
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jj420 Ex Member	Re: Will the Imperial SQ work outside? Reply #6 - 08/21/06 at 20:16:05 [quote author=Getafix link=1154605348/0#0 date=1154601748] I know the standard imperial is more recommended for PA but I not interested in the extreme SPL. I want the low bass with the authority only a horn can deliver. [/quote] pretty sure he has SO confused with SQ besides, both variations have high SQ LOL!
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footstony Ex Member	Re: Will the Imperial SQ work outside? Reply #7 - 08/22/06 at 07:19:46 Hi getafix, For maximum efficiency you should go for (massive) front loaded horns. see here http://www.audioasylum.com/scripts/etv.pl?forum=hug A back loaded or SO type configuration is ultimately limited by the efficiency of the driver. Regards Philip
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Adrian D. Ex Member	Re: Will the Imperial SQ work outside? Reply #8 - 08/22/06 at 08:41:38 the imp so IS a front loaded horn.
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jj420 Ex Member	Re: Will the Imperial SQ work outside? Reply #9 - 08/23/06 at 17:27:55 the SO is "front loaded", as Adrian says, while the Standard Imp is a back-loaded variant. The K-slot makes it tread into resonator tewrritory, but not by a lot... Correct me please if I am wrong, but isnt the overall efficiency of ANY system determined by the efficiency of its driver complement?
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Adrian D. Ex Member	Re: Will the Imperial SQ work outside? Reply #10 - 08/23/06 at 19:46:26 you're right about efficiency. the box only boosts up the efficiency.
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footstony

Ex Member

Re: Will the Imperial SQ work outside?
Reply #11 - 08/24/06 at 03:15:20

Hi Guys,

In terms of efficiency I was speaking about the standard imperial.
The standard imperial being a back loaded horn would have an efficiency in the mid bass region equivialent to the same driver/s on a very large/infinite baffle limited to around 100dB for one watt. The compression chamber forms a low pass filter for the horn output which could be up to 106dB for one watt in the bass region depending on the driver alignment and etc. The imperial is a great design combining a direct radiator with the potential for freak show bass!

You are right, the SO is not really loaded in the same way. I would be very interested if anyone has measured the efficiency of the SO and how does it compare to the efficiency of the same driver mounted on a very large baffle.

Regards Philip

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Getafix

Ex Member

Re: Will the Imperial SQ work outside?
Reply #12 - 08/31/06 at 08:43:53

Hi all, I did mean the imperial SO in my first post. As it is a variation in of a front loaded horn I was hopping it had the same sort of efficiency as a larger front loaded horn ( 105db+ @ 1w) but with even better sound quality and bass extension. Also Steve mentioned that the slot would extened the upper frequency by allowing upper frequencies to pass through.

Does anyone have a SPL plot for the SO yet?

Thanks for all the help

Getfix

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serenechaos

Ex Member

Re: Will the Imperial SQ work outside?
Reply #13 - 09/03/06 at 01:14:54

[quote author=Getafix link=1154605348/0#12 date=1157010233]
Does anyone have a SPL plot for the SO yet?
[/quote]
There were quite a few on this thread, but most of them are gone now:
Imperial SO has problems, need help
https://www.decware.com/cgi-bin/yabb/YaBB.cgi?board=Imperial;action=display;num=...
One’s still here:
http://www.mninter.net/~kuechle/graph1.jpg
dismal looking…

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Steve_Mac

Ex Member

Re: Will the Imperial SQ work outside?
Reply #14 - 10/21/06 at 22:26:01

I'm pretty sure the Who used the Imperials for outdoor concerts back in the good old days. No problem there at all. Currently I'm using BassMaxx horns with 18" JBLs and I'm sure they would be great candidates too. www.bassmaxx.com
Here's some links to the "cleaning" up and mods for home use I did with a set of these horns. I love em.
These are front loaded...
http://www.steevee.com/subwoofer/subs1.jpg
http://www.steevee.com/subwoofer/subs14.jpg
http://www.steevee.com/subwoofer/subs16.jpg

Additionally, check out www.soundphysics.com and www.danleysoundlabs.com ...I think they make some mac daddy subs... great for outdoor use.

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