Anyway to make Klipsch look-a-likes? (1 Viewer)

[Jeffrey Noel]

Ron, what would you recommend for the crossover? I am absolutely "crossover illiterate" if that makes sense. I have never soldered or done anything like that with electronics.

The 10" Klipsch driver, on PE's website, states that its frequency response is 32hz-4000hz, and the specs say that the recommended crossover for the Selenium D205TI is 1200hz to 2000hz.

So what would you do?

 

[Mike_A]

so ron, if you cut sensitivity by 6db, then aren't you going to have to attenuate the horn like crazy as well? And you won't end up with one of Klipsch's major advantages - high sensitivity, hence low power requirements. if i remember things correctly from my engineering days, a 6db drop in sensitivity is going to require a 4x increase in power to achieve equal volume levels?

 

[Jeffrey Noel]

Hmmm....the lower sensitivity thing is kind of disappointing, yet it will still be >91dB, which is MUCH better than my Technics towers which are rated at ~86dB. I still see it as a vast improvement!
Also, I've submitted the info for the Klipsch 10" woofer into WinISD, and here's what it shows:
Volume: 9.1 L
Tuning Frequency: 67.24 Hz
Port: 3" diameter/10.66" long (vent mach=.15)
SPL @ Hz
~93dB @ 116Hz-1000Hz
91.64dB @ 100HZ
90dB @ 90Hz
88dB @ 80Hz
86dB @ 70Hz
82dB @ 60Hz
As you can tell, the graph begins to drop at approx. 116Hz.
Remember, this is with only 1 Klipsch 10" woofer.
Ron, or anyone, would you recommend something any better to try, or does this look alright. I will be using this with either the 85L or 95L Shiva+PR off of Adire's website.
Oh yeah, any adive what crossover frequency you feel would be best?
Thanks again for your time and effort! It's GREATLY appreciated!

 

[Ron Shaw]

Yes, if you reduce woofer efficiency by 6db, you will need to attenuate the horn by that much, as well. You would still have the advantage of low (IM) distortion in the range covered by the horn, however. And yes, a 6db reduction means 4 times the power for the same SPL. This does go against Paul Klipsch's original idea of high efficiency = low distortion, but if one chooses a single bass driver (and not a high efficiency one, at that), then there isnt much you can do. What can you do to increase efficiency?

1. Use multiple bass drivers, as the original design did (every time you double radiating area, you increase efficiency by 6db), but this requires a larger box size.

2. Use a high efficiency driver. This means more expensive, as high efficiency costs money, and will probably also require a larger box size, as well.

3. Sacrifice bass extension. By reducing moving mass, a driver will have higher efficiency (and usually a higher F3).

What would I do? I would probably use a high efficiency woofer (or two standard ones) to up the overall system efficiency, and cross them over to a horn in the 500-800 Hz range (to get the benefits of horn loading in the critical midrange region.) The resulting box size will probably be at least 5 ft3, but it will hold no punches.

I have not run the parameters for the Klipsch drivers, but if you are correct, I personally would pass on this driver, as a 67 hz tuning frequency would not give me a low enough F3. I want at least a 30 Hz F3. For affordable drivers, I would off hand recommend using the Pioneer W25GR40-51F, available from Martin Sound for $51.20 ea. These are well made cast frame 10" drivers which give a 25Hz F3 in a 2.2 ft3 box! 90db at 1 watt. Two of these in a 4.4 ft3 usable box size will give you 25hz at 96db. The choice of drivers for low and high frequencies is almost limitless, just run the numbers until you find a suitable candidate.

I wouldn't necessarily try to copy the Klipsch unit, as the qualities you admire in it are probably just the sound of high efficiency (=low distortion), so if you just keep that goal in mind, there becomes many possible drivers to choose from.

Get the catalog from Martin Sound (or any other vendor you favor), and compare features/prices until you find something you like. The reason I keep mentioning Martin Sound is because they have a good selection of drivers, both dynamic types and compression types, and everything else you need to build a pair of speakers. Good luck. I will be leaving the 20th for the holidays, and will not respond to e-mail until about the 7th of Jan., so have a nice Christmas and a happy New Year.

 

[Ron Shaw]

Ooops! I should have checked the specs before my last post. The Pioneer W25GR40-51F I mentioned in my last post gives 25Hz in a 3.44 ft3 box, not 2.2, howver, its response in a 2.2 ft3 is still a very respectable 31 Hz. Soory for the mis-information.

 

[Jeffrey Noel]

Thanks a lot Ron, and Happy Holidays!

 

[Ron Shaw]

I should have read a bit closer. I see you intend to use a subwoofer. That being the case, it makes it a bit easier (and cheaper) to build the horn systems. The Klipsch woofer will do OK in that case, as the higher tuning frequency is still adequite, however, you may still want to get a driver with higher efficiency. A couple of good choices are the Eminence Alpha 8, with a sensitivity of 97 db, which is only $24.83 from Martin Sound. It is an 8" unit, which will have better transient response than a larger driver, and has an F3 of 54Hz in a 1.08 ft3 box. It is a stamped frame driver. If you want to spend a bit more and get a higher quality cast frame unit, the Eminence Kappa Pro-10 would be a good choice. A 10" driver, it also has a sensitivity of 97 db. It is $67.69 from Martin Sound. It would also work fine in a box of about 1 ft3. Either of these drivers, coupled to a decent horn/compression driver, would give high efficiency, low distortion performance. Both would require a subwoofer crossed over at 60 Hz or higher to fill in the last octave. A simple series capacitor at the input of the amplifier would give an easy 1st order rolloff to these units, and would eliminate the need for an active crossover on the top side.

 

[Jeffrey Noel]

Ron, I looked at these speakers on Martin Sound's website, but the price listed is about double what you say. Are these prices wrong? Or are they different in the catalog?

And do you know of any pre-made 500-800 hz crossover like you recommend? I found a 500hz one at partsexpress, but it was around $50 for one, which may be a little out of my range.

 

[Ron Shaw]

Hummm...you're right. The price on the net is higher. I got the price from the price sheet that comes with the catalog. It says '2001-02 Dealer price list', although Im not a dealer, these are the prices I always pay. Maybe I had better keep my mouth shut! I have talked to them on the phone several times. They are always friendly, and the prices I get are the same as in the catalog price sheet. Give them a call at 800-321-6306 and ask. If the price is really the price on the net, then maybe a bit more research is in order.

They also list a 2 way 800 Hz crossover (12db slope) for $19.19 ea., and a 500Hz 2 way for $23.87 ea.

 

[Jeffrey Noel]

Well Ron, I finally decided to go with one Eminence Alpha 8 in each tower, along with a horn tweeter.
Here's the specs for it from WinISD:
Driver : EMINENCE ALPHA - 8
Vas : 19.0
Qts : 0.56
Fs : 72.73
SPL : 97.00
--
Project by : Jeffrey Noel
--
Number of drivers : 1
Box type : Vented
Box size : 2.000 ft^3
Tuning frequency : 52.00 Hz
Vent : 1 vent(s)
3.26 in length for each
4.02 in round
Freq SPL
[Hz] [dB]
40.00 88.47
42.00 90.72
44.00 92.73
46.00 94.39
48.00 95.61
50.00 96.38
52.00 96.81
54.00 96.99
56.00 97.05
58.00 97.03
60.00 96.99
62.00 96.95
64.00 96.92
66.00 96.89
68.00 96.87
70.00 96.87
72.00 96.87
74.00 96.88
76.00 96.89
78.00 96.91
80.00 96.93
82.00 96.95
84.00 96.97
86.00 96.99
88.00 97.02
90.00 97.04
92.00 97.06
94.00 97.08
96.00 97.10
98.00 97.11
100.00 97.13
That's one hell of an 8" speaker!
Much more efficient than my 86dB/1m Technics towers.
Thank you so much for all of your time and effort. If I could I'd give you an award, or a pat-on-the-back!
Thanks for the Alpha 8 recommendation also!
Happy Holidays!

 

[Ron Shaw]

The Alpha 8 does pack a lot into a small size. This should give you a very fine sounding system. Couple a pair of these to a good sub, and you will have a good, high efficiency, low distortion system. If you need crossover info, let me know. I will try to help out. How are your soldering skills?

 

[Scott Simonian]

I saw one on the Martin webpage, it was a compression mid-range(D250/order#1866). It said it was phenolic. Does that mean that it is a piezo horn? Im looking into horns myself but I want it specificly for the midrange. Would this be good?

 

[Eric Kahn]

phenolic is a type of plastic, it is what the horn itself is made of

 

[Ron Shaw]

No, the horn isnt made of phenolic. It is refering to the diaphram material of the D250 driver. It isnt a piezo unit, but a standard dynamic unit, using a voice coil. This driver can be mated to a variety of horns. The D250 is a good driver, however, response starts to drop off at a lowish 3kHz, which means it will need to be coupled to a HF horn unit to carry the rest of the spectrum. Check out the Selenium site for curves on this driver. They spec it out to 9kHz, but response is down about 18db at 9kHz. I would use this unit from about 600Hz to 3kHz, and cross it over to a HF unit. Use the HC56-25 horn.

 

[Scott Simonian]

Yeah, I noticed that roll-off. Its ok cause that is what I am looking for, sort of. I was looking for a good horn mid-range. I guess it would be good to couple it with a good horn tweeter too.

But do these horn drivers that we've been talking about "really" sound good? Well, I guess anything would sound better than the frail, pos midrange and tweeter in my KLH speakers. UGH.

 

[Ron Shaw]

These drivers, when properly used, should sound very clean. Go to the Selenium site and look at the distortion curves. Typically 20db down for 5 to 10 watt drive levels (about 1%), and a good 30 bd down at a 1 watt level (.1%). Try to get this low distortion with a dynamic unit! In a typical residential enviornment, you will usually be feeding the horn drivers with a fraction of a watt average power. You will probably be getting more distortion from your amplifier at these levels than from your drivers. This also brings up another issue. Most (AB class) amplifiers produce more distortion at around 1 watt than at full rated power due to the output transistors going from class A to class AB operation (called crossover distortion). If you can find a good 5 to 10 watt amplifier, this would probably be cleaner than something that puts out higher power for a domestic application. A good 5-10 watt class A amp would be ideal, as there is no crossover distortion in these amplifiers, or better yet, a tube amplifier (now yer talkin). A good buy on an old Dynaco Stereo 70 would be killer for this setup!