Klipsch Efficiency

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I have been looking at the current reference line of speakers from klipsch and been wondering how they get them to be so efficient. Thier numbers stated are 97 db 1w/1m or greater. Anyone have any ideas how this is achieved or have any measurments to prove that it is not real?
 
My experience with Klipsch speakers revolves around the Heritage range, eg Klipschorn, La Scala etc. Yes their efficiencies are pretty accurate. Hornloaded speakers are as much as 9dB or so more efficient than an equivalent direct radiator, within their passband. For instance, the mid-horn on a Khorn is about 110dB/1W/m, between 400Hz and about 6kHz. My new mid horn looks like being 117dB/w/m from 400Hz to 22kHz. Thats what a near identical design measured with the same flare and different compression drivers which were spec'd at the same efficiency.

The direct radiators Klipsch use are just well developed and refined drivers whose engineering compromises have been chosen with an eye on efficiency. This is nothing new or magical: just take a look at what happens in the Pro-audio world, where DR efficiencies in the high 90's are commonplace and have been for 50 years. Read some of the driver spec sheets here
http://www.jblpro.com/pages/components/componts.htm
or at Pioneer-TAD, Fostex, EV, CV, Beyma, PD etc.

The late Paul W. Klipsch was an Engineer and a reputable man. Based on what I have seen published elsewhere, Klipsch specs should be pretty accurate. He hated "********" engineering.

Below is a quite exhaustive test of a Klipsch Cornwall.
http://www.belgaudio.com/kcmap.htm

Cheers
 
I have not listened to any of the new mass produced Klipsch speakers, though I have heard most of the earlier ones. I even owned a pair of the Heresy's. I don't know who made the 12" drivers but the tweeter horns were made by EV. From what I have picked up listening to guys that have owned some of the old gear Paul Klipsch did not make any of the drivers that were used in the speakers. High efficiency was the only way to go when your amp only put 20 watts and you didn't want to push it into too much distortion. Most all the speaker brands were efficiant before SS and acoustic suspension speakers. Now I think most of the small driver satallite type speakers are recessed (especially the tweeters) to gain a db or 2 out of the performance of the drivers and the below 80 to 100 hz is usually taken care of by a sub. Take the lows out of the equasion and it is easier to get higher SPLs. I did see some woofers that were rescently closed out by Klipsch that had some pretty heavy duty magnets, which usually points towards better efficiancy. These were copper colored alum coned and were made for some of the top of the line towers I think. If I was looking at new Klipsch I sure would drag a tube amp out to a store that sells them for a good listen first. Could be they are very good for what you want. Could you make better for the same money. You bet!
 
David or Anyone Else,

I am not trying to be a smart *** or anything but the last sentence of your post was, "Could you make better for the same money. You bet!". How exactly could I make a better speaker. I have been doing a lot of looking around for diffrent drivers and modeling them in a box on my computer. I have been unable to produce a box that is anything like the klipsch speakers. My boxes are either far too large but have good efficiency and bass extension, or lack one of these but are a reasonable size. The only way I have been able to achieve resonable efficiency is to use pro drivers but as stated above they require large enclosures to get any kind of decent bass. The klipsch speakers are both compact in size relatively speaking (around 3.5 cubic feet), have excellent bass extension (down to 40 hz or so), and high efficiency (97 db 1w/1m or greater). Any thoughts as to how I could achieve such results.

Mark
 
Mark,
I just took a look at the RF 3IIs. The two main drivers were the ones that ended up in a local electronic closeout shop and as a super buy ot Parts express.(Could have been end of run or slightly flawed?) First of all you probably could build something with the Eminence coax 10" 35-20K Hz at 97 db in the same size box at less than half the price unless you have to buy tools. High Q is good for Transmission Lines but this might be too high. The trouble is to me that it is a compression driver tweeter wich would work a lot like the metal dome in a horn the Klipsch has. I just find them a bit harsh, but that is personal prefference. I am going to be doing some junking at auctions to find some ESS speakers with the Heil AMTs to try out for tweeters before I make up my mind(I don't know the SPLs of the Heils) but I want to try a TL using the full range Eminence Beta( 40 to 10K hz) and a tweeter in a two way. It will end up a bit wider and probably quite a bit deeper that the Klipsch 3IIs but visually close in size. A pair of the 12" are going to run me around $150. I am hoping the cabs less than $100. The Heils who knows. Xover, BPs, wire etc.$75 for Vampire OFC and good caps. Then the Shahinians will go into the bedroom, the Altecs into the computer room and the Stromberg Carlson Coax into the garage. Lots of ways to do things but I am kind of focused on these TLs so if you want ported boxes I can't help you. I don't have any software, just a calculator.
David
 
does anyone knows how to calculate the overall efficiency of a speaker with following units:

tweeter: 117db
mid-range compressor: 108db
woofer: 98db

the measurement with db-meter showed 108.3 ... what's the deal?

Be aware that there is a distinction between efficiency and sensitivity. The first is acoustic watts out for acoustic watts in and the other is SPL on axis for a given voltage. They can be converted but only if you know directivity or polar pattern.

1 acoustic watt is 109dB in full space at 1m. If your radiation is hemispheric then this becomes 112dB at 1 m for half space radiation. Most units are even more directional so you need a number for d.i. (directivity index in dB).

With a typical high frequency d.i. of 10dB then a 50% efficient horn (the maximum possible) would be 109 + 10 - 3 = 116.

Scale from there.

David S.
 
Did you measure them indoors? outdoors? How did you measure the input power - are those numbers you give per watt or at 2.83V? What frequency? What distance? Is the woofer horn loaded? Bass reflex? Passive x-over or multi-amp?

Ideally, the overall efficiency (in this case) would be limited by the woofer, but in reality there are so many factors that come into play that there is no one great formula to use.

-bill
 
I've been interested in understanding how Klipsch comes up with their efficiency ratings only to determine they simply estimate high. I remember seeing measurements in magazines where their 97db per watt rated speakers really were 92db. Still higher than many but not as high as specified.

>>> but I want to try a TL using the full range Eminence Beta( 40 to 10K hz) and a tweeter in a two way...

I love the Beta 12 wide range driver! It's really a high efficiency driver (rated at 97 i believe) and actually sounds more efficient than all of the other drivers i have used over the years. For example, some Fostex drivers rated at 95 and 97db per watt sound no more efficient to me than other drivers rated at 91 and 92db... but the larger Eminence clearly goes louder with less power.

My current open baffle speaker using the Beta 12... very efficient and sounds great with tubes or T-amp.
 

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Be aware that there is a distinction between efficiency and sensitivity. The first is acoustic watts out for acoustic watts in and the other is SPL on axis for a given voltage. They can be converted but only if you know directivity or polar pattern.

1 acoustic watt is 109dB in full space at 1m. If your radiation is hemispheric then this becomes 112dB at 1 m for half space radiation. Most units are even more directional so you need a number for d.i. (directivity index in dB).

With a typical high frequency d.i. of 10dB then a 50% efficient horn (the maximum possible) would be 109 + 10 - 3 = 116.

Scale from there.

David S.
many thanks dude...
the first measurement at 2.83V at 1 meter distance was 108.3... I have no idea how measuer max SPL but at 165W@8ohm they rated 124db

Did you measure them indoors? outdoors? How did you measure the input power - are those numbers you give per watt or at 2.83V? What frequency? What distance? Is the woofer horn loaded? Bass reflex? Passive x-over or multi-amp?

Ideally, the overall efficiency (in this case) would be limited by the woofer, but in reality there are so many factors that come into play that there is no one great formula to use.

-bill
as I said we did measuring at 2.83V with frequency swipe... ideally the units (woofer,mid-range and tweets) will show their maximum efficiency when frequency swipe reachs to the frequency range which units are specified ... but the best thing is that testing the speaker with all 3 unites installed showed overall 108.3 db @ 2.83 ~ 1 meter distance... I think they are so efficient ... after all I think ear is the best tool to measure a speaker...

I've been interested in understanding how Klipsch comes up with their efficiency ratings only to determine they simply estimate high. I remember seeing measurements in magazines where their 97db per watt rated speakers really were 92db. Still higher than many but not as high as specified.

>>> but I want to try a TL using the full range Eminence Beta( 40 to 10K hz) and a tweeter in a two way...

I love the Beta 12 wide range driver! It's really a high efficiency driver (rated at 97 i believe) and actually sounds more efficient than all of the other drivers i have used over the years. For example, some Fostex drivers rated at 95 and 97db per watt sound no more efficient to me than other drivers rated at 91 and 92db... but the larger Eminence clearly goes louder with less power.

My current open baffle speaker using the Beta 12... very efficient and sounds great with tubes or T-amp.

thanks for the input... idea about Fostex is so remarkable... I used to think they are efficient as specified... what's you opinion about Audio Nirvana?

the speaker mentioned above is a Klipsch Cornscala (modified)... sound very good to my ear... never heard something better... like the way they sound... the overall look is fascinating to me... the budget was something about 2000 boxes... do you think there is something more efficient than these considering the money? if so I like to know what is the idea... the cheapest speakers rated above 105db that I saw is some horn-maker brands like avantgard etc... which are all above 30-40 grands up to 100grands!!
many thanks
 
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