PrestonTom

Congratulations on your K-Horns. You have certainly received quite a bit of advice. Enjoy your speakers, they really are special. I will note however, that Cal Blacksmith has given some very reasonable advice. You have some very efficient speakers and their impedance does not go very low (won't drain current from the amp). I would not worry about getting a large amp, however I would worry about an amp that provides very clean power. Otherwise, any distortion, hiss, or hum will be revealed. Also, believe me a 65 watt amp will not clip when driving K-Horns. The HK amp should do fine As Cal implied, at this point your biggest gains will definitely come from properly placing them in the room. Good luck, -Tom

I agree with Tom Mobley. However, in either case I think it will be difficult to get a clean edge (even and with no chipping). Also you do not want to do anything dangerous on the table saw. The work must be fully supported at all times. An alternative would be NOT to mimic the 60deg cuts. Use an easier joint if the cabinet is going to be veneered. Or use a "1 by" strip as a vertical member and placed in front. This can be done with a bit of design to look pleasing and will cover up whatever joint you have now hidden. Good Luck, -Tom

Joe, This is an interesting point. A 4th order would get about 24 dB/octave (this is an approximation, of course), as you mentioned the phase shift is now comparable. With the correct CF and overlap, there would be many advantages and at a reasonable cost. As you point out the levels would need adjustment because of the insertion loss. This all seems very attractive. Good Luck, -Tom

Two comments. First, the of 6dB per doubling of distance is only true in a free-field environment. That is in the absence of reflecting surfaces. In a living room, the drop off will be much less and it will also be frequency dependent. Second, the issue of symphonic music being well-over 100 dB is misleading. It is certainly not at this level for a sustained period. Additionally, a dB number by itself is not very informative. It is a function of the bandwidth (and if or how it was weighted) and also if was integrated. That is why these measurements should not be take to seriously. The details that went in to the measure are critical and are typically not well understood by the reader. Good Luck, -Tom

I will confess that I did not get past page 7. I thought much of the thinking was muddled. I also thought much of the "evidence" was nonsense. When performance is dismissed (either electrical or perceptual discrimination), then the flood gates open up for snake oil. The reason I get disturbed by this is that there are a great number of folks who truly would enjoy great music reproduction. Unfortunately they get burden down in some very trivial, but very expensive, aspects of sound reproduction. This is great for Stereophile (and their like) and for the boutique manufacturers. Now they can sell stuff that is outrageously priced and of dubious value (where value is function of both performance and price) . I am spoiled, I was able to get some K-Horns for a great price and I have complemented them with reasonable equipment. I get turned on every time I turn on the music. I wish others could have the same or a comparable experience. Sure, I will continue upgrading, but it will always be done in a sensible way. Believe me, the audio voodoo will not be driving the decision making. I wish others could also enjoy well-recorded and well-reproduced music. However, there is a legion of detractors who will continue to confuse every issue and to exploit and misinform. In part it is driven by ignorance, in part by the placebo effect and other expectations. But this biggest part is profit. Make no mistake, it is simple greed behind so many of these audiophile myths. Gee, what is the latest in cryogenically treating speaker cable ....? The logic from sterophile would be that a simple ABX-performance test in order to dismiss the nonsense is just somehow not right since it takes away from the "subtler experience". Enough of my ranting for now. Good luck, -Tom

I appreciate your problem in trying to decide. Let me point out a few things that are probably obvious anyway. People get very used to the sound of their own speakers. They then judge other speakers in reference to their own. I am from the old school and believe that you should compare them to live music. My next point is that "words" are not very good at describing the percepts. As an example, what is the frequency range of "deep bass"? I suspect that if you actually asked 5 people you would get 5 different answers. Further, if you gave those same 5 people a frequency generator, they would be surprised how far off their numerical estimates actually are compared to the sound that they thought was "80Hz". Next point, a speaker is actually a part of a system, that is the "speaker-room system". All these speakers will sound better or worse depending how they are located in the room, the size of the room, and the geometry of the room and how it is furnished. You will notice that most of the comments that have been offered concern sonics occurring from about 400Hz and below, usually well below. Well these frequencies have wavelenghts exceeding 2.5 feet, (below 100Hz, then it is in excess of 10ft). With these long wavelengths, the room and the speaker position are absolutely critical. As such, one must take all these comments with a grain of salt. I believe the folks are truthful about what they are hearing; however, many of their comments may reflect the speaker-room system rather than the speaker itself. Not all is lost, you have been made an offer to hear K-Horns. Go ahead and listen. See for yourself. Good Luck, -Tom

Moon, Very nice!!! Good Luck, -Tom

Jeff, I had the same experience last night in Connecticut. Admittedly, this is the holiday rush with many inexperienced staff running around, but Klipsch is not shown to its best advantage. Perhaps Klipsch is best experienced in conventional stereo store, rather than a warehouse setting. Or perhaps I am just a old guy remembering how things used to be ... Good Luck, -Tom

John, This is almost an urban legend: picking up a pair of K-Horns for next to nothing. I agree with Jeff about removing the formica and applying some veneer. There are a number of choices and finishes that will make them look absolutely beautiful. If you have never done this before, it is not that difficult. Practice on something else first. There will some effort involved in getting the surface smooth and the corners & edges to have nice square & crisp surfaces. But it would be a fun project. You will surely get advice about updating the crossovers. This can be as simple as a straight replacement of the capacitors, which is not that expensive. Additionally, and I am not sure about the vintage or how to test, sometimes the magnets may need to be re-charged. This seems to be especially true for the Alnico magnets on the tweeters. There are places who can do perform this. Others can chime in on this issue also. But I am being pessimistic and I don't mean to be. These are a fantastic find, enjoy them. Imagine, something that is over 45 years old and all the excitement it is generating. Good Luck, -Tom Forgot to mention - corners are critical (they will sound even better). If none are available, then building a false corner (or a half corner) is a good option. There are various plans/designs available that range from the simple to the more complex.

That has a very cool effect! Good Luck, -Tom

Certainly the topic has drifted. But this issue of how much should we rely on measurement, especially as the first step, is of a personal interest to me. It is probably best considered as a continuum. Clearly there are some folks who are toward one extreme and discount many of the advantages afforded by physical & performance measurement. Dr Who tends toward to the other end of the continuum, where measurement is the key. Similar to Dr Who, I also favor the measurement approach. Quite a bit can be learned from this approach. Quite a bit of nonsense can also be avoided (the typical audiophile voodoo etc). When the argument sinks to the level of name calling, then the Dr Who's of the world seem even more reasonable in their reliance on measurement rather than notions from the "black art". Good Luck, -Tom

Jim, I will respectfully temper (disagree with) my colleagues opinions. Careful on the sanding, the outside ply is not very thick. Even if you do sand as much as possible, just short of going through the ply, the stain may still not come out (and you run the risk of sanding through the top ply). Regarding the bleaching: my experience has been with hardwoods (esp oak). My bad luck has been that if you use bleach you run the risk of getting a purple discoloration. If you use oxalic acid (preferred method) then the course of events is that there is no bleaching then all of the sudden it becomes bleached far too much. The stuff is tricky to work with (at least for me). Good luck, -Tom

Jim, Sorry to hear the bad news about the cabinet. Things happen .... Before you do anything. Please be very careful. The birch ply will not take much sanding - be very careful and do it very slowly. Are the cabinets otherwise unstained, was the birch raw? I am not optimistic that you can make this problem disappear. Some judicious staining might do it if you are lucky Good Luck, -Tom

Saltyhook, It's an interesting issue. First, a false corner (or half a corner) is not all that difficult to build. With a bit of creativity, you can actually get it to look acceptable (WAF ....). I have both K-Horns (early 80s) and Cornwall 2s (mid 80s). My perspective concerns mostly with the low end response (the mids and highs will sound more similar rather than dis-similar between the K-Horn & Cornwalls). It is the lows that really differ (although I find the mids to sound a bit more nasal on the Cornwall). The K-horns have a better, more accurate, and cleaner bass response. I believe this is a reflection of the greater efficiency that the corner loaded horn provides. While the Cornwall does not go as low (the very low end), it does have plenty of bass, but I do not consider it to be as clean sounding or as dynamic. It is difficult to describe the sound with words. Before anyone jumps on me, the Cornwalls do sound good, very good. However, the K-Horns are something special. They also cost more. Typically, the Cornwalls will sell for about 600-800 and the k-Horns for about 1600-2400. Much of the variation is due to finish and condition (these prices do NOT include shipping, which is not trivial). There is also a great deal of variability in cost due to location. These are not easy to ship, and if you are the only guy nearby who is willing to pick them up, then you can frequently get a deal (in my case about half the normal used price - but you must be patient). Incidentally the top section of the K-Horn is easily removed (wing nuts) but the total weight per overall cabinet is about 160-170 lbs. You are quite correct about the issue of placing the K-Horns in corners. It is critical. However, many folks ignore that proper positioning of a Cornwall is also important. It really is more than tossing them in the room and leaving space for whatever else.... Good Luck, -Tom

Kriton, How do you know the finish was lacquer? If it was a homemade finish, who knows what they may have used (urethane or who knows what). You are probably correct in assuming the bumpiness was due to dust while it was drying (although, they may have done something to raise the grain - e.g., some water based product). I am only guessing at this point. One way to spot lacquer is to see if it disolves in lacquer thinner (urethane will not). It looks like there are a number of challenges with the drips, brown color and what not. You are very correct in being careful not to sand too much. If the surfaces are not marred, are you comfortable in applying a veneer? This would open up a number of options for you. My experience with veneer is that the second time you do it, the results are quite abit better. So go ahead an practice on something else first. Good Luck, -Tom

I would wait a few months. The cabinets appear to be in good condition. However I agree with the above comments about holidays and heating prices. When I got my Cornwalls (2s in oiled oak & pretty good condition) several months ago, I had been following the prices on eBay etc. Your asking price of $825 is a bit on the high end but certainly not unheard of. Why not wait a bit. Good Luck, -Tom

Just a few thoughts on the open cell foam treatment. My experience is with the stuff distributed by Sonex. First, there is an out gassing. So when it first installed, you will smell the organic compounds. Some are sensitive to this, others are not and it will not last forever. Second, some of it is paintable. It will slightly change the absorbtion coefficient (but not drastically). Third, some of this stuff will release some nasty stuff if a flame is held to it - it smolders. Different brands may have different properties. This last point raises another issue with room treatment. If you suspend stuff from the ceiling or on the wall. It will usually work better (absorb more sound and down to lower frequencies). But let me caution, that this also raises the red flag on fire issues. Suspended flammable material is not always and leaving an air gap behind it makes it even worse. It is something to keep in mind. Good Luck, -Tom

Artson, That is a very clever way to access the different taps. will be upgrading to an ALK universal this coming year. I know I will want to go back and forth testing the different squawker settings. You have just saved me a bunch of time. Good Luck, -Tom

Dr Who, Thanks for your thoughts. You are absolutely correct regarding the conundrum: On a continuum where the endpoints are either an anechoic chamber (no echoes or reverberation) or conversely to a reverberant room (where echoes are maximixed, yet the SPL is relatively uniform thought out the space): where do you want to be? That is a good question. There are certainly answers when it comes to concert hall acoustical design. But I am not trying to impose an additional concert hall on to what was originally recorded. On your other thought on the time-alignment. Yes this is a tangent to the question, but there is an interesting relation to room setup issue. Basically, and simplistically, the bass bin effectively needs both to be in a corner yet at the same time about 6ft "in front" of the top section. This difference in propagation delay, would effectively re-align the drivers having different path lengths. I am ignoring the comparably slight difference in path length between the mid and the tweeter. How to solve this. Well I can't have a corner "in front" of the top section. However, one could have the bass bin on the floor and position the top section in the corner but substantially elevated toward the ceiling (and angled downward). My rough calculation, to create an extra 6ft (or about 6ms), would require the top section to be elevated by about 17 ft above the floor. No, I only have an 8ft ceiling. So I can not do this trick. But consider this for a moment. It does not require any outboard equipment (no added distortion in the signal path), no extra amplifiers. What could be simpler! Does anyone have barn? Good Luck, Tom

Zealot, You are posing a rather tough question actually. The choice of microphone is not as important since ultimately you will be making repeated measures throughout the space. If there were no boundaries, then the SPL would drop off at a rate of -6dB per doubling of distance. This in fact is part of the ANSI standard for measuring the low frequency cut off of an anechoic chamber. One can play this trick also to get a sense (spectrally) of the standing waves in a room. The problem with using Freq domain approach (i.e., Fourier) is that it does not really tell you about echoes, only their results via standing waves and room modes. Inverting the FFT to go back to the time domain is tricky, since the algorithm assumes that the signal started a very long time ago and will contnue for a very long time. So the time information you get is the ongoing phase of the constituent cosines - if they were continuous. With a transient signal, the algorithm, in effect, asumes the transient is simply repeated indefinitely. There will be various nobs" of the machine to apply various windows or filters; however, these must be used with some underlying knowledge of what is being done inernally. In this regard, many folks using an FFT & applying various windows are unintentionally filtering or smearing the signal. Basically, with a many approaches (including FFT), you are either going to get spectral precision or temporal precision, but not both. In fact this headache is why waveform analysis using wavelets is so attractive, since you can get around some of this uncertainity. Alas, I am about to go off on a very different tangent .... I'll stop. You really need the time-domain measures. Even a simple one like looking at the output on a scope (with the right test signal) will give some very solid clues about where the dominant reflections are coming from and also a ore macro vies of decay times etc. Although this can be a tedius process. Good Luck, -Tom

Westcott, I appreciate your comments about the floor. But I am stuck on this one. The house is already built. The floors are hardwood. Currently there is an area carpet with a pad underneath. I will have to work with this (also the floor can not be raised since I only have an 8ft ceiling). I also agree about the open floor plan being forgiving. I am banking on the various openings (to kitchen, hall, front entry) to alleviate some of the "building up" of the low frequencies. This also gives some nice asymmetries. I am also sympathetic to your comment about the about the uniqueness of horns. I do, and will continue to, have my horns positioned so the listening chair is at a 45 deg with each horn. Your right in pointing out the advantage of direct to reverberant energy in this configuration. It also has the advantage of a flatter freq response since the listener is on-axis with the speaker and minimizing any off-axis frequency response drop off (I think this is sometimes forgotten about by many folks). The other, and more obscure, advantage to the 45 deg placement, is that the listening sweetspot is enlarged (left-to-right). I won't go into here, but for anyone interested there is a nice pictorial description in one of the Dope from Hope issues. Good Luck, -Tom

Mark, I know of someone who actually did that. His reasoning, in part, was that it provided a rock solid image. It is interesting to note that when doing that, the room acoustics problems are actually increased. Having two speakers, packs the room modes (standing waves) more closely together. This gives a more even distribution of SPL as a function of both frequency and location. With a single speaker, you lose some of that advantage. Good Luck, -Tom

Gil, Thanks for your thoughts and I will certainly keep everyone posted (I think our solutions will be of interest to everyone). As a starting point RT-60 decay times (I remember them as the "Sabine decays") are probably a good starting point. Although trying to keep them uniform across frequency will be tricky (trivial at high frequencies and requiring heroic efforts at low frequencies). This will be a blast getting back into this topic again. A number of years ago I was the technical point of contact when our lab was renovating the anechoic chamber and reverberant rooms in our suite of laboratories. I am certainly familiar with Everest's Book. There was another more technical book by Kruttoff (?) on room acoustics. It was older but provided a solid technical background. My goal is toward some workable solutions that are flexible, visually pleasing (at least not annoying), appropriate for others to borrow, and will not entirely alienate my girlfriend. I will begin in earnest sometime in Jan (once my kitchen renovation is finished). Good Luck, -Tom

Folks, I am bit embarrassed to confess this since I actually work in audio. I will be finishing up a kitchen re-model, which of course has taken 3 times as long to complete then as I predicted. Which leaves me time for my next project: Serious (or semi-serious) sound treatments for my listening room. I live in a raised ranch and use the living room as my listening room (K-Horns with 2-channel music & no eye toward home theater). The room is limited by 8 ft ceilings but measures 12 ft deep by 19 ft wide. The width spills open to a front entry stairwell, and a hallway. The depth spills open to a wide kitchen entrance with a cutout (window) between the rooms. There are enough complications so that a simple geometric model will not work. But the good news is that the space is not terribly small. First question: When Artto and others first tackled their environments, what was the first step. As a scientist, I am inclined to do some subjective evaluation about what I like and don't like and then follow this up with some physical/acoustic measurements before starting My dilemma is the measurement issue. Naively, one could use some long-term signals (flat noise or warble-tones) and measure long-term frequency response. This could tell me about standing waves. This frequency domain approach is attractive since it is straight forward and easily implemented ( I can borrow some of the equipment from work). However, the disadvantage of a frequency domain approach is that a highly reverberant room can also generate a sound field with a uniform SPL (room modes are densely spaced). Such a reverberant room can sound terrible (believe me I used to work with these). What about the time domain? There are ways to measure this also but what about the treatment? One can diffuse, trap, and absorb much of the sound but then what are you left with? An anechoic chamber describes this extreme. Believe me you would not want this for your room. It is a rather dead environment (believe me again, I used to work in one). Again you would decrease the echoes and reverberation (at least at some parts of the spectrum), but the frequency response of the Speaker-Room system would not be flat. The other aspect is sound deadening (making the room quiet & decreasing room-to-room transmission). This is difficult to achieve since the room already exists (this is NOT new construction) and this is also an "open" floor plan (which allows it to be a "larger" room). Where does one start? I assume I will re-read my time domain measurement handbooks, borrow a microphone and spectrum analyzer and check out some DIY projects on fabricating sound absorbers, sound diffusers, and bass traps. And by the way, the treatments will require some aesthetic design criteria (you guys have girlfriends and wives so I don't need to explain this...). Your thoughts please (and this should be an ongoing dialog), -Tom

i have exactly the same room / same experience] Duke, It sounds like you live in a raised ranch also. Actually my Winter DIY projects will be to measure/listen/install some room treatments. I am going to make it even better .... Good Luck, -Tom