WMcD

You did the right thing. We're proud of you. Now you're gonna be an authority in the community. Congrats, Gil

Symphonic Star Trek and Great Fantesy Adventure Album, on Telarc. When Telarc has low bass, there is a warning on the label. Seek it out. I also like The Songs of West Side Story on RCA, but it is just music. Gil

The question is poorly phrased in some ways. It implies some conditions which do not exist. Thus tough to answer. And, below, I'm telling some things you are touching upon by implication, or accident, without knowing it. Still, technical accuracy counts for something. The Klipschorn, strictly speaking, is the the big corner horn assembly. I suppose some would narrow that to the bass unit alone. Still, when you speak of the Klipschorn, it is only the big corner unit having a bass horn, a mid, and a tweeter. (The Klipsch organization has always maked a lot of speakers with individual horns. But the Klipschorn name should be restricted, in my mind.) The expansion of the Klipschorn bass unit is essentially exponential. In it, this means the area doubles every 16 inches in length. This is a shorthand, but accurate, way of explaining the more complicated exponential equation. The K-400 midrange is also exponential in expansion. It double in area every 2.25 inches. The tweeter in the K-Horn, I'm not so sure about regarding expansion. It is an EV unit. My guess is that it is not strictly exponential. The tractrix design is incorporated in more recent units. The design is too complicated to explain, here. However, in the Klipsch line up, there are no tratrix bass units. The tratrix midrange started to be used with the Forte II and Chorus II, now out of production. At least that is my understanding. In the more recent series, a single "tractrix" horn is used for the treble. Direct radiators are used for bass. The tractrix horn was originated in the 20s and 30s by Voight. It makes an assumption about how the sound wave will be propagated down the horn as an arc of a circle, or sphereoid, and this implies an expansion which is not exponential. None the less, it has its own advantages. I believe you're wading into some good natured, but serious debates on the forum. Q: Can I find new Heritage for sale on the internet? A: No. The factory does not have them in production but promises them "soon". Q: What is all this "tractrix" about. A: It is a newer design for the treble. Q: Which is better? A: It is all very good stuff. - - - - Let me go out on a limb here from a technical point. The K-5 by PWK was an effort at a constant directivity horn. The tractrix treble horn follows that. In a hazy way of thinking, the recent Reference series are a bit like the Cornwall or Heresy in the low end. They are optimized direct bass radiators. They are mated with a tractrix treble which seeks the same goal as the K-5. It is like we have an updated and downsized K-5 with a better bass direct driver system. Others may well disagee. However, that is how I see it. Gil This message has been edited by William F. Gil McDermott on 07-30-2001 at 11:28 PM

So Stu, What is the cross over problem. Is this accidentally misfiled in this thread. Gil

It is a good point. Klipsch did advise of update on the cross overs to the K-Horn and I suppose by implication, the Belle and LaScala. This was generally replacing the A type with AA, etc. I've not heard of other manufacturers doing this with any line of speakers. One justification for not doing this with non-Heritage speakers might be the nature of the construction. The crossover is easy to get at in the Heritage. With others, there is a bit more work to it. Finally, is there a market for it? We live in a pretty small world in this bbs. Gil

I posted a tale about a similar problem. My brother-in-law had bought some new interconnects. The sleave on the RCA connector was so tight that it was difficult to get it plugged in. Further, pulling it out was, I think, challenging the physical integrity of the connection on the amp. Ray G. reported a similar problem. If you get new interconnects, there may be no way of telling whether they'll have the same problem. If I have to fool with the system again, I'm going to widen the sleave with a pair of pliers. It is frightening to think that the expensive interconnects can physically damage the equipment they're attached to. Gil

John, Okay, I would't doubt you. Gil

I speak a bit from ignorance. However, I wouldn't expect that all products are going to switch over to a new material immediately, even if it is better, or cheaper. I'd think that the woofer manufacturers may have a big stock of cast or stamped frames, or long term commitments to purchase from parts suppliers. A switchover is costly in itself and that would have to be justified by a significant savings in the short run. Therefore, it is probably inaccurate to conclude that "plastic" is not a good development, simply because all product lines, and producers, haven't jumped on the bandwagon right away. Gil This message has been edited by William F. Gil McDermott on 07-26-2001 at 08:49 PM

I saw a tip years ago that nail polish remover might do it. Maybe that was from the days of rewinding slot car motors. Yeah, that long ago. I don't recall if I tried it. Gil

So, Mr. B, For the benefit of others, what do think the problem was. Do you think that lack of aiming the horns to the listening position gave the impression of too much bass, but it was actually too little treble? Maybe a bit of both, and the return to the orginal position cut the bass enchancement? I'm sure the question will come up again. Your thoughts would be enlightening to all. Nice call, Kevin S. Gil

It is a cheap experiment. So there is no reason not try it. OTOH, the series resistance will definitely make a difference to the sound. First, there will be some loss of level. There is also reason to believe there will be boomier bass. This because modern box based bass system design assumes the speaker is fed with a source having a zero, or near zero impedance. Short runs of big gauge wire helps keep that true. However, the resistance of the thin wire will increase the Q. That leads to a peaked bass driver movement at resonance. I remember an article in Speaker Builder, the back page. It was about a lad who gained the unfortunate moniker of "Chrome Dome". This was because his dad forced a radical, short haircut. Not the rage then, as it is now. In any event, the article described a "bass booster switch". All it did was insert an 8 ohm resister in the circuit. Because of lack of damping, the bass was peaky and boomy. Less informed people thought it was an improvement. Edit and PS: If this is a K-Horn, LaScala or Belle, the bass might still boom. One reason for a bit of doubt is that the horn is already contributing to the damping of the driver. So it might not be so pronounced. But at resonance, the amp still should have some effect. Additionally, the series resistance does alter a recognized design parameter for optimum throat size of a horn. PWK cites to a Bell Lab paper for setting throat size based on driver parameters. There is a complicate equation in there. There is a factor of "n" in the equation which takes into account the internal impedance of the driving amplifier. Don Keele used the same equation in a paper which converts the Bell Lab equation into one using T-S parameters. He recognized the "n" and assumes the internal impedance of the amp will be zero. PWK and Delgato uses the Keele equation in the Jubilee design AES paper. The bottom line is that if you add series resistance via wire, the throat size is no longer optimum. Designers of the midrange and tweeter may have made the same assumption. Gil This message has been edited by William F. Gil McDermott on 07-25-2001 at 09:50 PM

This adds to our advice base. Most questions go to whether a given type of wire will sound better. Now advice we give should take into consideration the ease of working with a given type. I've found that black rubbery lamp cord is easy to strip. On the the other hand, the clear plastic stuff is a bit more of a challenge. It is not something I ever gave much thought to. But obviously ease of stripping is a consideration. Gil

I'd point out that most of the "hostility" is comments by people favoring Heritage speakers over the recent vintage. Most of that is just an effort to keep Klipsch up to the highest, or oldest, standards. I like MP too. Gil

One of my systems has barrier terminals on the amp and speaker. I use the u shaped spade lugs which I solder to the wire. This makes changing things around much easier. I'm not a fan of high priced interconnects. Cheap stuff from RS is often gold plated and that is enough, in my book. There is something to be said against connectors where the wire is just held in place, and the electrical connection is made, just by a screw down device. Now you've got a potentially cranky mechanical connection to the wire, and other potentially cranky mechanical connection between the plug and receptical. None the less, it is probably a better set up if you're doing any moving around. It may also be easier to take care of polarity. So a reasonably priced connector system is a good investment. On the other system, I just use bare wire. I don't fool with it much and things are just fine. Gil

This is a can of many worms; more like bucket of snakes. If you don't mind a lecture.... At least it is free of charge. = = = = = The switching of transmission and reception points relies on reciprocity. I.e. switching the locations of sub speaker and ears yields the same result regarding room reflections. The polarity switch should not alter results. In case this hasn't been stated, the polarity switch just means the diaphragm is moving out and in, rather than in and out. Just like hooking up the wires wrong, black to red and vice versa. With a mono source of sound, i.e. one sub, you can't hear it. At least in the bass. (Perhaps we can in the treble, when things are right. A subject of debate.) = = = = = The polarity does come in to play when there are two or more sources. Which is what we were talking about. One instance where there ARE two or more sources of bass is when the mains (two sources) and the sub (the third source) are both generating bass. However, that should occur only in the cross over band of frequencies. This is where, in a perfect world, the mains are not quite fully shut off, and the sub is not quite turned on. Roughly, each system is putting out half power at the cross over point. This is at about 80 to 120 Hz. This is called "constructive interference". However, if the distance difference is one half wavelength, you get destructive interference. And flipping polarity solves the problem. At least it causes constructive interference. (Perhaps an oximoron.) Please note that once we move the subject musical note above the cross over frequency band, the sub is not working. When we move below the cross over frequency band, the mains are not working. Therefore, the polarity switch usually only addresses an issue which exists in frequencies near the cross over point. I.e. can we turn destructive interference into constructive interference, with a flip of the switch. = = = = = = = Of course, with two subs, we've got another problem. Now the two subs are working from the cross over frequency, and down to their lower limit; a wider band. I'd agree keeping them both the same, or normal polarity, is a good bet. = = = = = = = = I depart a bit from the original subject. You'll see how it all fits in. "Phase" is a very tricky term. As the Tappet Brothers point out, explaining things is difficult. One must balance between being accurate and incomprehensible - - - or comprehensible and inaccurate. Maybe all four at once. Phase is used to discuss phenomenona which can arise from several causes. Consider a sine wave. (We need diagrams. Imagination may suffice.) If you look at the second half of the cycle, it is the same as the first half, but inverted. Therefore, if you can delay the arrival time of a sine wave by a time for half a cycle to occur, it is the same as inverting the sine wave. Reversing polarity accomplishes the same thing, you invert it. If you've got the same delayed sine wave, inverting the polarity restores it to the original form. Now, you say, this is simple, and Gil has been saying the same thing over and over. However, it is not quite so simple in real time at different frequencies. A sine wave in air with a frequency of 100 Hz has a wavelength of 10 feet. It takes 10 milliseconds to go through a full cycle. 5 milliseconds delay is equavalent to 180 degree phase shift or reverse polarity overall. But consider that a 50 Hz sine wave has a wavelength of 20 feet. A 5 millisecond delay is only 90 degrees of phase shift. Flipping the phase switch doesn't restore things (if we have a 5 mS offset). It becomes equivalent to just adding 180 degrees, and you wind up with a 270 degree phase problem instead of the 90 degree; and they're similar. You can't win. I'm getting in deep water here, which is the goal. How do phase, time delay, and polarity all fit together? This is the deep water. We see from the above that a uniform delay (5 milliseconds) causes different amounts of "phase shift" depending on the frequency of the sine wave. If the bass guitar player moves down the scale, the 5 mS delay now has caused a different amount of phase shift, actually reducing it! Nothing has changed except the note. Specifically, at 100 Hz, 5 mS is worth 180 degrees (half a wavelength), at 50 Hz, it is worth 90 degrees (quarter of a wavelength). Therefore we see that if time delay is uniform, it causes a different phase shift depending on the frequency. A uniform delay seems to cause an increase in phase shift with frequency. Is polarity the same as delay? In our primary example of 100 Hz, a 5 mS delay has caused a 180 degree phase shift, and we correct it with "polarity". Big, big, peripetetic (Sp?) question. Does that mean that the polarity switch, which "inverts phase" causes a time delay? Think a while. No, it is just a simple switch which effectively wires the sub backwards. In fact, since it alters phase by 180 degrees, it is always worth half a wavelenght. But at high frequencies, half a wavelength is equivalent to less absolute time delay. This is because the sine wave wavelength changes according to frequency. = = = Now you can see how the subject gets so confused. We know that the switch is not a delay at all. However, it acts in a way similar to a delay. Yet the delay it is eqivalent to is related to frequency / wavelength. Quite clever for a mechanical switch. = = = = = To close the loop, let's apply the concepts to two subs, near to each other. Flipping the polarity switch on one sub causes a 180 degree phase shift at ALL frequencies in that one relative to the other. (The same is true of one main speaker being wired "out of phase" with the other.) We see that we have destructive interference. Here, at all relevant frequencies there is no difference in arrival time (no delay). So we have polarity equal to phase shift, but no time delay. In other cases, we had time delay equal to phase shift, depending on the frequency! = = = = Err. Does that help or just create confusion? Best I can do tonight. Gil

If the question is "delay" because of a long cable, I wouldn't worry. Two rules of thumb. Sound at sea level travels at 1000 feet per second. Light in a vacuum travels at 1000 feet per microsecond. That being 1 / 1,000,000 of a second. Cables have a "velocity factor" which is the factor by which the electrical signal is slower. I think one approximation we can make is that the cable has a velocity factor of 0.1. So it is travelling at 1/10th the speed of light. We just can't hear the delay. Loses are another matter. 2 dB (mentioned) is a more than I'd expect. Still, it is something that can be adjusted at the HT amp. Keith, what gauge wire is that? Do I understand that an extra 16 feet of wire caused a 2 dB loss. That is odd. But going back to the original question. If you are getting a loss in the run to the surrounds, so be it. I'd say it makes little sense to cause the same problem with the mains by duplicating the long run to them. I can't see that having the same problem (even if a small one) all around is "better" than just having it in the surrounds. Of course, this is just a opinion and some experimentation might well show I'm wrong. Gil

KAiN64, Congrats. I see this is your decision. Does this mean you don't have the hardware yet? No matter. You'll like the set up, very much. I got my first enlightenment just by setting up the TV audio output to my stereo system. It was not "Home Theater" yet made a big improvement. I recently a problem where my main Sony TV failed. Before taking it out to the dumpster I took it apart to look at the speakers. Gee wizz, they are very small; similar to what is found in a computer set up. This is not your situation. But let me comment. If anyone out there wants to get into "Home Theater" the first thing they should do is to find the output plugs from the TV or VCR and hook them up to whatever stereo system they have. Big improvement. The best use of equipment on hand. Gil

There is a nice publication by the Audio Engineering Society at: http://www.aes.org/technical/documents/AESTD1001.pdf The technical jargon may be too much for some (I had to chew on it). It is problematic that "5.1" is used to describe both the number of speakers (this is a speaker hardware issue) and the number of channels of transmission and storage (this is a different issue). We have to be careful. I harp on this only out of the belief that it has lead to confusion, and deserves careful articulation. Forgive me for stating the obvious if you know all this. OTOH, we have people browsing the forum and this is part of the learning curve. In any event, there are two nice diagrams. The first sets out the ITU recommendation for speaker placement for 5.0 (without sub) and/or 5.1 (with sub) sound speaker set ups. Note, "surrounds" are not in back, but just a bit to the rear of 90 degrees left and right. This would apply to systems using either Dolby Pro Logic (2 channel storage and transmission) or Dolby Digital and DTS (5.1 channel storage and transmission). The diagram just goes to speaker placement. The AES and ITU are not saying this is the only way, just a recommedation. The second sets out a block diagram for the combination of LFE channel and additional redirection of the bass from the main channels. This assumes a 5.1 storage / transmission system as in Dolby Digital and DTS. I.e. 5 channels plus an LFE channel (0.1). But this should be taken with a grain of salt in consideration of settings of "Small" and "Large" on the processor / HTS receiver. It shows that the LFE (Low Frequency Effects) storage / transmission channel is sent to the sub. (It fails to show that if you don't have a sub, LFE is sent to whatever speaker is set to "Large"; or that your setting should be that.) The 10 dB amplification is just there to say that the gain is pumped up. room". Don't worry. It also shows that bass below 120 Hz in the 5 other channels is sent to the sub. Note the use of L and L' (etc.) in the input and output of the processor, indicating that L' output means the bass has been redirected to the sub, or at least filtered out. Of course this assumes that any speaker with a prime (') has been set to "Small" in the set up of the receiver. You might be setting only surround, e.g. LS and RS, to small. In which case your L, C, R, is still getting whatever is in the feed channel. The .pdf document is well worth printing out and studying if you have questions about (1) a starting point for speaker placement and (2) LFE channel and redirection of bass from the other channels to the sub. Please note this does not address a situation where the sub is getting its input from the speaker output wires. Regards, Gil

This is a bit of a simplification. But consider what happens when the sub and the rest of the bass system cross over at 100 Hz. The wavelength there is about 10 feet. Half a wavelength is 5 feet. Therefore, if the sub is 5 feet more distant than the woofers from the listening position, it is half a wavelength different in phase, at that frequency. This means the 100 Hz acoustic outputs are cancelling. If you reverse polarity with the switch, they are back "in phase". This is simplistic because it only addresses that exact frequency and that exact difference in distance. Room acoustics, the roll off rate, crossover point, actual spacing all conspire to make it a more complex set of interactions. Therefore, it is important to experiment with "phase" (actually polarity) and placement of the sub. If you've got exactly the right problem, the switch of polarity might solve the problem. Otherwise, you might have close to the right problem, and it is an improvement, or maybe makes things worse overall. In short, it gives you an extra tool to work with, without being a universal cure. This shouldn't be specific to any type of music. However it is possible that a given combination of factors (polarity, cross over point, speaker locations) produce a good result at one point (say 100 Hz plus) in the bass response, and a bad one in another (say below 100 Hz). Therefore, music heavy in bass in one point might sound better or worse. Klipsch FAQs point out that one way of reseaching the placement of the sub is to put the sub at your listening position, and then walk around the room to find a place where the bass sounds optimum (whatever that is for you). Then put the sub at that location. In theory, this can't take into account the effect of bass from the mains, and the interaction which the polarity switch is supposed to address. It seems like you're using two subs. That injects another level of complexity for which there are single guidelines. I'd definitely say to keep them both set to the same polarity. As an experiment you might try putting them next to each other and switch one to the inverted mode. You should recognize a marked reduction in bass. You might find that putting both subs in the same corner gives lots of bass, maybe too much. Putting them in different corners might be too much too, but worth trying. Moving them to a central position on adjacent walls (e.g. left and back) might be a good choice too. No one can tell without experimenting. The final issue with two subs is that common wisdom is that people can not locate bass below 120 or 80 Hz, meaning there is no "stereo" effect for bass. To get stereo bass it would have to be in the mix to begin with and you have to have the subs feeding off left and right outputs of the amp. Wendy Carlos claims to be able to detect it. But that assumes it's in the mix to begin with. Given Carlos's credentials and experience, who am I to argue. Gil This message has been edited by William F. Gil McDermott on 07-20-2001 at 07:18 PM

I bought some RCA brand wire at HD. The choice was only based on price for that gauge. The cardboard label said it was "high definition." To me it was just the run of the mill zip cord, here with a clear insulation. I can't believe there is anything especially "high definition" about it . . . not that I think it needs improved definition. Gil

I'll assume that John is serious. This might be an illustration that "great minds think alike." On the other hand, such is hardly inductive and deductive logic. Weak minds may think alike too. Gil

It seems that you're looking for a ranking between: 1999 LaScala, 1970 K-Horn, Current K-Horn, Maybe current LaScala, or anything else. As per your comments, my guess is that there are few outside the factory or a fully equipped dealer, with a good memory for sound, who can report first hand experience. Side by side tests of the range of choices are nearly impossible because of the cost and circumstances of time. I think it is fair to say that the 1970 K-Horn is a gold standard which can not be matched by any LaScala, or any other speaker in the world short of the new Jubilee. The home Jubilee has not come to market. People have some opinions on tweeks and upgrades to the K-Horn over the years. These mainly go to the midrange and tweeter. They can be implemented in the 1970 K-Horn, should you wish to tinker. I can give you info. My suggestion is that you should not hesitate at all to purchase the 1970 vintage K-Horn. It will be a remarkable improvement over the LaScala in bass. I certainly don't criticize the LaScala. However, the bass of the K-Horn gives a tremendous impression of authority and ease of reproduction overall. I'm not a member of the "subjective sound" camp. It is simply difficult to quantify in terms of frequency response. You can't go wrong with the 1970 K-Horn. I'm confident you'll be very happy. Gil

Yeah, I typed the word and knew, just knew, there were going to be comments. Us guys all think alike. My observation is that PWK went to steep cross overs and the tweeter protection after high power amps came on line and users had the means to blow out drivers. A close reading of the Dope From Hope did not actually say the new cross overs were superior in sonic performance to the old ones. Maybe they are, or maybe not. People like Al K. cross overs which have steep slopes. The point is that if the tweeter protection device is defective, it could be jumpered out. This would do no harm unless one is driving the system so hard that damage is a possiblity. Gil

I sent DLU the schematic for an AL-3. All I have of that family. I see it has a tweeter protection gadget which is something in parallel with a 100 ohm resistor. (This in series with the lead to the tweeter.) One thought is that the protection circuit opened up and DLU is hearing some signal thru put via the resistor. If this is in the AL, is it not self healing? I don't know. This is all guesswork. Al would know better. So, perhaps jumpering out the protection unit will solve the problem. Of course, then there is no protection. Gil

We're making progress. The scratching noise from the tweeter when being tested for continuity is normal. A small amount of current is being passed through them by the probe. Re cleaning. I'd try a vacuum cleaner hose first. Also maybe blowing things out with a product from RS. Liquid Air or the like. Why don't you tell us the model of the cross over. It might have a fuse for the bass and another for the tweeter and mid. But you should be missing the mid if that one has blown. There might also be a tweeter protection device. Experts can tell you. I'm a bit to hear the spade lugs on the woofer wire broke. You can just reattach the wires as you suggest. Or RS will sell you some spade lugs and a cripping tool. Observe polarity in any case. Hooking an audio source as a brief low level test was okay but I'd be real careful running anything to the tweeter without the cross over. It could well burn it out. Gil