Guy Landau Posted November 11, 2003 Share Posted November 11, 2003 I would like to clarify that I do think that the ALK networks are fine. I have bought a pair of networks from Al K. even before I've joined this forum, and had been listening to them for nearly 2 years (or more) and was quite happy with the way my Khorns sounded. I have decided to build the type A's, out of couriosity and they sounded better to MY EARS. I don't run any test equipment and only counted on my earing and the fact that I was living with the SAME system for a very long time and was familiar with its sound. I have tried both Multicaps/Hovlands for a few weeks and the Oil caps and have prefered the oils soundwise. I had no way to test them and was running them with a 20 Watts, triode connected, Marantz model 2 monoblocks. I know that there's no tweeter protection but that is, IMO, one of the reasons that it sounds so open and reveiling, And I didn't found it to be such a flaw. Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted November 12, 2003 Share Posted November 12, 2003 With quality amplification, tweeter protection is a moot point. The only time I have EVER seen tweeters blow is from POOR amplification run over its limit. Drop in a cheap high power amp and problems might result if pushed beyond the limits. Like Guy, I too find the better oil caps to be VERY good, sounding big in naturalness and lack of artificial sibilance. To me, this "crisp" sound that Al refers to is not natural. I have not heard the ALKs in my Cornwalls but offered to audition them and write a review. This didnt pan out. Now the ALK CW is no longer made but Allan Songer has discussed the option of an audition. If you havent seen this before, here is the Type A that Guy built. Quote Link to comment Share on other sites More sharing options...
UncleRobb Posted November 12, 2003 Share Posted November 12, 2003 The type A Xover doesn't work for me... Here is what I did: After work, I visited the local Radio Shack to buy some switches and other material for my new project. This is a modification of my type AA Xover such that I can: i) switch off the Zener diode protection; and ii) switch between type A and type AA. The latter is done by a 2-pole switch that: i) removes the 245uH inductor from the network; and ii) deactivates one of the 2uF caps. Additionally, I removed the screw that holds the top board of the 245uH inductor. Both don't seem to be necessary. In type A mode, a 1kHz tone generates a very significant distortion in form of overtone(s). I double-checked my wiring. Everything seems to be OK. It seems to me that for some reason, my amp doesn't like the type A network. Any explanations? Thanks, Robert Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted November 12, 2003 Share Posted November 12, 2003 Robert, I like your A / AA switch idea. That would really be a good way to compare the two networks. I did some computer analysis on the A and AA tweeter filters. At 1000 Hz, the type "A" will be down -20 dB. The type "AA" will be down about 53 dB. The only sound a T-35 will make at 1000 Hz is distortion! I would think 20 dB should be enought to quiet it though. 20 dB attenuation represents 1W to the tweeter with 100W into the speaker. Al K. Quote Link to comment Share on other sites More sharing options...
UncleRobb Posted November 12, 2003 Share Posted November 12, 2003 That is great Al! I plan to do some measurement with my 2-channel scope this night after work on the amplitudes of the tweeter and squawker signals. I would not be surprised if one could indeed clearly hear distortions mixed with a pure sine tone that is 20dB louder. With music, this might be more difficult. However, I believe that I hear some distortions here too. Robert Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted November 12, 2003 Share Posted November 12, 2003 Somehow, mounting a series of switches in the mod does not strike me as the best solution for comparing. Think of the improvements by removing the various spurious components in the Type AA for the sonic improvement. Now drop in some switching to compare the Type A. Most that prefer the Type A have VERY revealing systems. I have never heard this complaint from any. kh Quote Link to comment Share on other sites More sharing options...
UncleRobb Posted November 12, 2003 Share Posted November 12, 2003 Al, I just did some measurements to find out what signals are output to the squawker and tweeter when a 1kHz harmonic wave is fed into the Xcover network. In type A mode, the tweeter gets a signal that is indeed attenuated by 20dBV. When I remove one tweeter connection, the distortion disappears. In type AA mode, I cannot measure any 1kHz signal coming to the tweeter. By the way, I discovered that my amp generates a 1MHz signal that is also fed to the tweeter. Thus it appears as if the A type Xover lets too low frequencies to the tweeter which, in turn, creates the distortions that I hear. I would not call this high fidelity... Robert Quote Link to comment Share on other sites More sharing options...
artto Posted November 13, 2003 Share Posted November 13, 2003 ---------------- On 10/17/2003 4:33:23 PM Al Klappenberger wrote: Shawn, Sorry I missed the light bulb and resistor in the tweeter circuit. This is supposed to be a tweeter protection circuit. I do not like it! A light bulb gets higher resistance when it heats up, but a tweeter will blow long before a light bulb will heat up! What's needed here is the Polyswitch used in the later Klipsch networks. The best thing is to forget the protection circuit and just keep a lid on the volume control! Al K. ---------------- I have to agree with all that Al. I even cut the light bulb protection circut on my 67' Standel bass amp (sounded way better). And the best thing is to just keep a lid on things, be reasonable. Have a question for you though. You keep mentioning 'constant impedence'. The impedence curves I've seen of the Khorn is anything but 'constant'. If my memory serves me correct, Richard Heyser in his very thorough technical review of the Klipschorn showed the impedence varying from well below 8 ohms & over 40 ohms. Doesn't the impedence vary with regards to frequency? And if so, how is it 'constant'? Quote Link to comment Share on other sites More sharing options...
Randy Bey Posted November 13, 2003 Share Posted November 13, 2003 Constant impedance (to me) is a phony argument. From what I understand at the same time that the driver's impedance makes it hard to drive, it simultaneously is at it's most efficient, which balances everything out in the "big picture". If not the case, virtually every amp/speaker combo would be very uneven in response and unlistenable. Al's crossover (and I shouldn't be speaking for Al, although I am) was based upon a concept of constant impedance when presented with a virtual speaker load as opposed to a real reactive speaker load. The results, when measured by Klipsch, were not as flat as Al's careful design would have shown. Probably flatter than with no such attention, but I think Al didn't bother to publish the test results. As well, Al was intrigued by the concept of "designer" parts improving the sound. This continues to be his motto, that good parts make a good crossover. I however am using "motor caps" as mentioned above in a type AA crossover changed to a type A by a couple of wire clips, etc. The results are fantastic. IMHO. In my stereo. In my house. In the city I live in, in the state I live in. Doubtless no one else would have the same results. So don't try. PWK liked the A best. I think there was a good reason. But I'm probably wrong. Quote Link to comment Share on other sites More sharing options...
Guy Landau Posted November 13, 2003 Share Posted November 13, 2003 You are not wrong. Quote Link to comment Share on other sites More sharing options...
Cut-Throat Posted November 13, 2003 Share Posted November 13, 2003 "I however am using "motor caps" as mentioned above in a type AA crossover changed to a type A by a couple of wire clips, etc." Randy, did I hear your system with the type 'A's ? As you may know type 'A's are what I am running in my Belles. I am a Believer! Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted November 13, 2003 Share Posted November 13, 2003 Guys, The drastic impedance variation that you see in the impedance of the Khorn (Belle and LaScala) is a function of the autotransformer. When you attenuate the level with a transformer the impedance seen across the primary is equal to the square of the turns (tap) ratio times the impedance of the driver. This comes to 13 Ohms times the square of 1.414 (tap setting 4-0) or 26 ohms. In my design this impedance is swamped back down to 8 ohms by a 10 Ohm resistor in parallel. That combination comes to 7.22 Ohms. Because I am using taps 2-5 and X-4, the combination is closer to 8 Ohms. The fact is that I have measured (and posted) the complex impedance of the Belle woofer and have measured the impedance of the K55V squawker. The K55v has a nearly resistive 13 Ohms. The woofer is also a fairly resistive load. I will measure and post it also if there are any arguments about the fact. When applied to a crossover designed to be constant impedance the impedance presented to the amp will, and is, also very flat. Randy, I have here the impedance plot done on my prototype network in a Khorn by Trey Cannon in the Klipsch anechoic chamber several year ago. I had it posted on my web site for a time and was asked to take it down by Trey. Which I did. If you would like to see it, I will be happy to email a scan of it to you if you will have Trey give me permission to do so. You will see that it is quite flat. Please refrain from repeating rumors that are quite definitely false! Please also, do not try to speak for me. This is one thing that makes me quite unhappy! Al K. Quote Link to comment Share on other sites More sharing options...
John Warren Posted November 13, 2003 Share Posted November 13, 2003 (edited) jw Edited December 17, 2013 by John Warren Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted November 13, 2003 Share Posted November 13, 2003 John, To translate what you said into English, a poor driver makes a poor speaker. The network is just one link in the chain. A constant impedance network is simply one of links in the chain. It will not compensate for a bad driver. Any driver will operate better if it is driven properly and any amp is better off seeing a good load. Sime more than others. As with all the links in the chain, it's the total that counts. Al K. Quote Link to comment Share on other sites More sharing options...
John Warren Posted November 14, 2003 Share Posted November 14, 2003 Al- This arguement would hold if I was dealing with high quality drivers, but the Heritage stuff is junk level. Chain is only good as the weakest link and, in the case of the Heritage line, the drivers are a "broken link". Just my opinion, of course. jw Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted November 14, 2003 Share Posted November 14, 2003 John, Well, I agree that the drivers are not the last word in anything, but I point at the squawker horn as the weakest link. Replacing mine with an Altec 811b really made me a believer about that. Even with a K55 driving it. You have to think 3-way of course. The K55V was designed to go DOWN and handle gobs of power, not up! Al K. Quote Link to comment Share on other sites More sharing options...
cwm Posted November 15, 2003 Share Posted November 15, 2003 Good Lord! So, $6000 a pair for "junk" drivers? I guess it proves the point that even "junk" if properly implimented can sound good............ Quote Link to comment Share on other sites More sharing options...
3dzapper Posted November 15, 2003 Share Posted November 15, 2003 I think I will change my handle to Fred Sanford for I've got "junk" in my Khorns and Heresys. "Here I come Elizabeth. This is the big one!" Rick er I mean Fred Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted November 15, 2003 Share Posted November 15, 2003 cwm, This was the genious of PWK. He was able to get more bang for the buck than anybody I know of out of what was available. Back in 1950 and 1960 the materials available were nothing like they are today. Anyhow, "junk" is a relitive term! Al K. Quote Link to comment Share on other sites More sharing options...
Randy Bey Posted November 16, 2003 Share Posted November 16, 2003 and what I understand is that PWK instituted very high QC on the parts he sourced. I am reminded of Grado cartridges, where they make a big batch of carts, and then measure them. By chance, some are better than others, and a few are better than all the rest. They sort them out and price them accordingly. PWK knew this type of thing happened and took advantage of it. Ah, but I forget that MD prefers the sounds of low distortion cone speakers. That nasty horn mouth distortion plays on his mind. Quote Link to comment Share on other sites More sharing options...
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