Klipschorn Original Specs

[boom3]

Okay, who is boom3 that he was on a first name basis with The Man?

Love the plots in that article Gil -- very close to what I have. Nice "dirty curves".

Actually I called him "kuhnel"-I think he liked that

I think we've all seen the Belgian review of the CW II. Their curves are quite unsmoothed and yet are pretty darn good for a speaker in a real room. I tell people, if you can get that kind of response in a real room, at your listening position, you are doing very, very well.

Peaks hurt worse than valleys because the ear/brain system will "fill in" valleys (the Kuhnel called them 'troughs") to an extent, but peaky speakers can be very irritating. I think it's the overall shape of the curve that makes the consistent difference. As Floyd Toole points out, below 300 Hz, the room is in charge; above that, the speaker is in charge.

This is probably a good time/place to point out an interesting experience. A few days ago I was experimenting with an old JVC ribbon tweeer, that averred (another favorite word of Paul's) flat response well beyond 20 KHz. Hooking it up to my trusty HP oscillator, I found that my hearing fades out above 13 Khz. I'm 58 years old. A friend who is 9 years younger can hear up to 13.7 KHz. When I was 19 I borrowed an oscilator from school and hooked it to my Koss headphones. I could hear up to 17 KHz, and my 5 year old nephew said he could hear up to 19 KHz. When CRT TVs were the norm, I could hear the 15.75 KHz tone of the flyback, especially if it was an older set. I worked in a TV shop when I was about 24 and I could find which set was powered up in a room ful of cabinet TVs just by that sound.

We've all been conditioned (brainwashed?) to think that 20Hz-20KHz is the "best' or "only acceptable" response for a speaker, yet real music, real listening environments and real ears (especially middle-aged ones) don't bear that out. I hope nobody ever dismissed Klipschorns because they "only" went up to 17 KHz (I think the current K-77 averrs to go up to 19 KHz).

[WMcD]

As I recall, PWK had technique for making room measurements for the K-Horn. I may have posted the learned article from which he was working.

He'd run a curve on the typical chart recorder with the microphone in one location. This might have been his own Klipsch Logerator (which gave a logarithmic vertical scale. Naturally the test tone would have to sweep up in freq at a predetermined rate to match the horizontal scale which would be logarithmic too.

Then he would move the microphone to another location and move the pen on the chart recorder to the beginning again. And run the new curve over the first one. This would be done several times with the microphone moved around the room.

Then he would trace the top of the combined overlaid graphs and take the result as the actual result -- at least for the bass. This might be why people say he drew the response by hand. But it was a structured methodology and not wishful thinking..

We know that room reflections cause destructive interference dips at the ear and measuring microphone and they shift as the ear or microphone is moved. If you shift the frequency a bit, the locations of the dips move.

If you use one microphone position there are some work arounds. In one case, a warble tone centered on one freq is used. Say it warbles over 1/6rd octave at 60 Hz (or band limited noise these days). Then you're recording the range of the freqs in the warble, an calling it 60 Hz. Then you move on to other freqs.

The other way these days is to gather all the data in a pure sweep. Then average over 1/6 octaves.

My guess is that PWK's multi position of the measurement microphone is as valid as anything else. This is because the single location measurements give a result for that location. It may be that his technique is closer to the power response of the speaker in at least that room. Granted, you room may vary. Smile.

WMcD

[djk]

PWK used multiple mics each with its own preamp. The outputs were fed into precision rectifiers, and then the voltages were summed for a composite response. This is a very good way to do things, even today.

[Dr Morbius]

Thanks for those vintage spec sheets - Super!

[sunnysal]

so we see again that 35-15 response is about right for a k-horn....sounds good to me!!!! warm regards, tony