Richard C. Heyser's Klipschorn review

[ClaudeJ1]

One thing's for sure, the Jubs with the 402 horn don't need a tweeter as the highs are as crisp and detailed as anything I've ever heard.

Claude, I presume you're aware of this, but the Jubes as we heard them in Indy was already using a tweeter driver, the K69 on the K402. It's the midrange driver they dropped.

Well, it would make sense to do that, since the Jub system is a 3-way for theater, mostly for power handling in it's theater application. For home use, the inverse square law and reverberant field of a small room is your friend, as opposed to filling a huge space with padded walls, seats, and lots of people, so most people listen to less than 1 watt on average.

Besides, the Jubilee bass bin goes way higher thant a Khorn bass bin, so they can cross it at 500 hz or higher. I think the K-69 was a good compromise over the 113x driver, which is for more power at the expense of the highs.

With it's 2-inch throat, and theater appllication (read "the big stuff"), I guess, technically, it could be called a "tweeter driver" although I don't know of any home tweeter drivers that are larger than a 1" throat. Of course this is just based on reading everything and only one listen. You own Jubilees, so you are more qualified that I am to post about it. I'm still tweaking my Khorn setup and I'm really spoiled by the JBL tweeters, although I hear that the Beymas are just as good or better for less money. So many options, so little time..................

[DrWho]

Heyser measured the tweeter/squawker offset to be 1.672ms. At 1.132ft/ms, that's 1.89ft. So basically, the tweeter needs to be pulled back so that it is 22.7 inches further away than it normally is when mounted on the baffle. At the same time, you need to make sure that you're not introducing new early reflections. And you will also need to undo the phase rotation built into the passive network that is compensating for the steady state phase offset introduced by the time-arrival differences.

[ZAKO]

I started experimenting with electronic xovers about 1970 and was interested in what Richard Burwen was doing with operational amplifier modules...I built a stero control system based on his design featured in Audio mag. Oct.1974 ...Time alignment circuits were part of my addition to the design....Over time other units were brought in sutch as Mark Levinsons designs on active xover units....also Pioneer,s D24 and D25 ,,,Nikko,s D23...I never liked the sound of the Rain units....But is a good cheap starter xover.....Sure the cost of going in with six mono block amps is a great hurdle for some.. But in a two way like the Jubilee it cuts the cost down some what....But I think biamp or triamp plus alignment serves a higher audio benefit and to me IS well worth it. I have never turned back....Sure ive tried some of the modern passive designs but some how they always fall short....You can try ALK super duper extreem slopes but i can dial in that same slope instantly with out tearing out all that passive garbage...I hear all the time OH THE COST !!!! THE COST hell...the bottom line its cheaper time wise for me to flip a switch rotate a slope than all the muss and fuss ...Time alignment is easy this way for me i dont have to calculate a new circuit and cut a new board of parts....No Ill never go back to passive,,,And be damn the cost. Roy,s approach to a active unit is a good start for the Jubille, but can be built on for better bi amping... I think Dean shot himself in the head for short changing that approach. I throw down the glove and challenge you to find me a better approach. AND DONT GIVE ME THAT HIGH COST CRAP. Your not building a mansion. Just a great audio system.

[ClaudeJ1]

I started experimenting with electronic xovers about 1970 and was interested in what Richard Burwen was doing with operational amplifier modules...I throw down the glove and challenge you to find me a better approach. AND DONT GIVE ME THAT HIGH COST CRAP. Your not building a mansion. Just a great audio system.

I never me Richard Burwen, but when I worked for Irwin International in 1980, doing all their PC board designs for a whopping 10 Megabyte hard drive, I worked with a mechanical engineer named Dave White. Dave and Walt Jung did a lot of cookbook audio and special projects back then. Dave had worked with Burwen and told me the guy was a friggin' GENIUS. He could tell jokes and design servo circuits in his head at the same time.

Dave's large home made electrostatics with trans-line sub and big tube amps was the ONLY time in my life I ever Electrostast play loud. They were amazing.

Maron I look forward to all your posts and it seems like you hold back a lot of good information until you get mad enough about something to post. Keep up the good words!! It's all good.

[ZAKO]

Yes I do get mad...sorry about that...But I see alot of talk but the " DO" part stops...and nothing gets done...I guess i just did it all when i was younger having some of the best guys lead the way. kicking me in the butt if I I slowed down.

[Groomlakearea51]

"Final crossover that I liked was a fairly extreme with bass simply ending at 450; mid starting at 400, ending at 9200, high starting at 8800."

The Klipschorn midrange driver/horn combination doesn't go a lick past 6kHz. So I guess what sounded good to you had almost 3000 cycles of suckout.

Dean: Tells me alot about my ears!!! LOLOLOL!!! Seriously though, I went back this morning and found that an "attention to detail" error had caught up with me.... [:$]

On the Klipschorns that I was playing with this weekend, I had left the Selenium D250X mid driver on the mid horn, and it "officially" dies at 9000, so that' why it sounded ok. Took it off and put 55's back on, and voila!!!, the missing cycles were instantly obvious. So I tried again with the mid/high set lower to around 5000, and it sounded better.

On that note, I like the D250x, but it's very, very bright "out of the box", so I use it with an 10w attenuator and with passive crossovers. It works best with the BEC's CT-1526 tweeter and the A/4500 crossover mod in the Klipschorn (and the LaScala). I use both the CT's, and 77's in the various Klipschorns, LaScalas, Corwalls, and Heresy's, and which sounds better really depends on the speaker/ crossover. I really like the CT's with the 4500 crossover mod, but also really like the 77's with the DX midrange. Go figure!!!

Oh well, carefully packed the Rane up and have to take it back not later than Tuesday "close of business". I wish I had more time to play with that type of system. Besides, my wife told me to clean up my "mess" of wires, amps, crossovers, etc. laying all over the place and make the place more presentable or else....[:-*]

Great thread, I'm really interested in the possibilities, and hope that some of the folks experimenting (and those who have) keep posting what they have found out. All in all, an "active" pre-amp with the ability to dial in delays would be a great idea. Hopefully, some "experimentals" will be further discussed here when they are tested.

[gaspr]

Truth be told, we're already building this product for one of my design
labs...but we're going a step further. We're designing an active
crossover preamp that also has digital amps built in (we're calling it
an active amplifier). The whole thing should cost under $500 to build -
and we're using the same Sharc DSP's that DEQX is using.

















Depending on how things turn out, the amps might be in a totally
different enclosure - in which case we'll essentially have a 6 Channel
amplifer and a 2x6 active crossover.

Sounds like a great idea Doc. Would your system have to interface with a PC as does the DEQX?

[ClaudeJ1]

Truth be told, we're already building this product for one of my design

labs...but we're going a step further. We're designing an active

crossover preamp that also has digital amps built in (we're calling it

an active amplifier). The whole thing should cost under $500 to build -

and we're using the same Sharc DSP's that DEQX is using.

Depending on how things turn out, the amps might be in a totally

different enclosure - in which case we'll essentially have a 6 Channel

amplifer and a 2x6 active crossover.

Sounds like a great idea Doc. Would your system have to interface with a PC as does the DEQX?

Seems to me that the price of admission for this kind of fun is the Behringer Unit, priced at $250-300. It's got time delays and such. Play with that and if you like it, buy the expensive stuff.

[ZAKO]

Sorry you have to take the Rane back...Its fun to get up in the middle of the night and try dialing in something different......My basement system looks like a rats nest also....A passive xover design bugged me so i Frankenstein rigged up a filter and time alignment for audition of a Marantz 19 reciever....That borrowed unit goes back to 1970.....still a great design though. I guess my wife will find me down stairs dead,,, hand on the volume control wide open some night, Mahler,s 2nd symphony (Ressurection) going full blast. Knowing her she,l peel my fingers off the control, turn it down..And go to bed...

[kev313]

Doc and Mas - Thoughful and insightful answers guys, thanks.  

[tigerwoodKhorns]

Doc and Mas - Thoughful and insightful answers guys, thanks.

I didn't know that Kelly (mobilehomeless) was back...

[kev313]

Doc and Mas - Thoughful and insightful answers guys, thanks.

I didn't know that Kelly (mobilehomeless) was back...

?

[tigerwoodKhorns]

Not you Kev.

Look at threads from about 2002 or so. Lots of pontification.

[pauln]

Based on Dr. Who's note, if the distance from the listener to the tweeter is pushed back 22.7 inches (line of sight using strings) relative to the midrange, and the tweeter leads reversed, and reflections from the top of the La Scala supressed... the tweeter mounting on the new La Scalas is easy to remove... the only variable that remains is how high an elevation of the tweeter above the top of the La Scala...

I'm tempted to try this. A wire frame made from coat hangers could be easily made to hold the tweeter in place above the La Scala. Would be simple to adjust the height - what would be a good height to begin with? Any other issues?

[DrWho]

Would your system have to interface with a PC as does the DEQX?

No, we plan to make it fully configurable from the front panel. However, we plan to implement a PC interface since it usually involves less keystrokes.

[DrWho]

Based on Dr. Who's note, if the distance from the

listener to the tweeter is pushed back 22.7 inches (line of sight using

strings) relative to the midrange, and the tweeter leads reversed, and

reflections from the top of the La Scala supressed... the tweeter

mounting on the new La Scalas is easy to remove... the only variable

that remains is how high an elevation of the tweeter above the top of

the La Scala...

I'm tempted to try this. A wire frame made from coat

hangers could be easily made to hold the tweeter in place above the La

Scala. Would be simple to adjust the height - what would be a good

height to begin with? Any other issues?

Assuming a perfect coverage pattern with the K77 (which I doubt to be

the case), you'll need to get the tweeter high enough to keep the 40

degree coverage off the top surface of the lascala. You should also be

aware of the fact that changing tweeter height also changes the

perception of the speaker. I think the height difference would

dramatically alter the sound (better or worse is up to you). Also,

there is phase rotation built into the crossover in addition to the

polarity on the tweeter being flipped - ultimately you would need to

remeasure in order to determine how much the phase needs to

adjust....well....I suppose you could try calculating it based on the

time-offset, but I wouldn't rely too heavily on that.

All that to say....I think there are issues outside the realm of time-alignment that might screw up the sound. "It's all about compromise"

[ZAKO]

K77 ....Remember the tweeter is a diffraction device...the dispersion is quite high...120 degrees .....Without a anechoic chamber your attempt would be futle......We have a chamber at the institute for the deaf made that test many years ago I.ll try to find the charts. Hmmmm what file cabinet?