PrestonTom

Robble, Not to add more headaches to your decision, but..... Some of the cabinets you are considering have a passive radiator in the back. As such, they would need to moved away from the rear wall. All cabinets are sensitive to room placement but this is a consideration above and beyond. Good Luck, -Tom

Merkin, You are asking all the right questions. Please search some of the earlier threads. There has been much discussion on this topic (although some of it is hidden in some vitriolic attacks as I recall). In terms of conditioners for dealing with transient drops in voltage you are quite correct, a battery will do this. To a certain extent a huge capacitor will do this also. This is what they used in the computer industry where the issues were critical. Not all is lost. Remember the power supplies on your amp etc also have a transformer followed by a large capacitor - this will also help with momnetary drops in voltage from the wall. Unfortunately, not unlike the voodoo surrounding cables & wire, some have seized upon this as a way of confusing folks ( I am referring to line conditioners not surge protectors - which should be used). Consequently you can pay quite a bit for fancy line conditioners that are dubious regarding their impact on the sound. And as we have all seen before, there are folks out there who will swear to their virtues. Usually the comments will include: "revealing, detailed, opens up the sound" etc. Save your money. If there is an actual problem, such as a pop or click when the refrigerator or air conditioner comes on, then some remedy may be required. Forgive my cynical nature. Issues regarding sound reproduction are usually matters of physics, room acoustics and engineering. They are not matters of voodoo. I hate seeing folks waste their time and money on the dumb stuff. Good Luck, -Tom

Alkemyst, Sorry about your misfortune Back to your original question.... As I understand it your cabinets are oiled oak. The ring may have come from water; however, you usually need the dampness to be sustained over a longer period (eg, potted plant). Sometimes, a cleaning solution that contains ammonia might do this (it reacts with the tannins that are natural in oak). Anyhow, short of a great deal of work, there is no simple solution. If you do get advice, make sure it is from someone who has actually done this on a similar finish (do not rely on second hand opinions - " my neighbor knew someone who .....") Havng said that, the labor intensive option (and it assumes some expereince) is to lightly strip the finsh from the top only (chemically not mechanically). Then very lightly sand the top (very fine-grit) being careful not to round the edges. This is only to smooth the surface since the grain will have been raised from using the stripper. Once it is dry, put a few drops of paint thinner on. The color that you now see will be the color if you simply oil it without any using any pigments in the oil. The match will no be perfect, however, if you only do the top surface your eye is forgiving since the other cabinet surfaces are not parallel and adjacent. Otherwise, you will need to use a pigmented oil. Matching the color requires experiementation. The experiment can be done neatly on the cabinet bottom I assume (this will be hidden anyway). I recommend Watco danish oil finishes (although the sheen may differ - so only use it on the one surface & do not try to "blend" in the other surfaces). The common trip ups will be to try and sand the stain away (do not do that) and to treat more than just the single surface (stay confined to the one surface). There are some who think the Formby products may work. I have not tried them - I do not know. If you do that (and it would be easier, if it works) make sure you hear it from someone who has actually used it to fix a dark ring on a oiled hardwood veneer. Good Luck, -Tom

JJ, First of all, enjoy your speakers. My thoughts: Do not worry about speaker cable. The room you are in is smallish. I believe the biggest effects will come from experimenting with speaker location, placement (you already have gotten a good start) and room treatment. Next is treating the room and others are giving good advice. However, I will add that part of the treatment can include things like an area rug (or not), or carpet pad (or not), or rearranging furniture, moving your chair away from a rear wall or decorative items on the wall. This is fun thing to tweak. It is best to get some good recordings and listening to them with different configurations. Do this to the point where you have various (revealing) passages fully memorized. You will be listening for the clarirty, imaging, the accuracy in reproduction in various instruments & voices, and whether you hear new things that were formerly hidden in the background. You need to get an accurate description of what aspects are good and which ones need improvement. It gets especially complicated when you then try to communicate this to others. For the low frequencies, the solutions are more complicated. Certainly bass traps are a viable option. Although pulling the cabinets away (or toward) the rear and side walls should also be tried first. This will not eliminate standing waves but it may shift them either in frequency or location so it is not as bothersome. As far as the Adcom amp. That is a good unit and can deliver lots of power and current (although this will be less of an issue in your case). These are good first steps (my opinion) and should be exhausted before you start swapping amps (you already have a good one) etc. Good Luck, -Tom

Michael, Good question! I have always been hooked on the Blue Note & Impulse recordings from late 50s through early 70s. Some great music and some excellent engineering. You mentioned the Jimmy Smith - that's a must. Another one that blew me away recently was a recording by Roland Kirk. I am stumbing trying to remember who was on the Hammond B3 (Ira somethng-or-other). The very first cut, Roland Kirk simultaneously plays a sax and one of his inventions (sort of as a drone). That is the set up. This is followed by the Hammond just cutting loose. Ahhhh, it was wonderful. The only detraction is that on a revealing system, the tape hiss from the original recording can be annoying. Such is life Good Luck, -Tom

Dr Bill, Quite perceptive! Normally I would not mention an electronic instrument since part of the reproduction includes the various distortions in the original production. K-Horns certainy shine without any of that. However, there is something about the tone from the B3 and the vibrato produced by the Leslie cabinet with the spinning horn. I love the sound. As a youth, I spent a good deal of time listening live to a B3 (I was in a garage band). Last year after doing some room tweaking with my K-Horns, I put on Jimmy Smith (Blue Note or Impulse recordings) and I was "there". I was transported back in time to a garage back in Calif where we practiced ... A wonderful experience. Perhaps this reflects my bias. Good Luck, -TOm

Just a thought. Why not use a Cornwall cabinet placed on its side. If you are more adeventurous, then replicate the Cornwall (and place it on the side), but realign the mid and high for a preferred orientation of the horns. The advantage is that much of the tweaking has already been done for you, courtesy of klipsch. I would suggest using the same drivers, horns, damping material & crossovers. The voicing should be identical (perhaps differing slightly due to altered peaks & dips due to floor bounce & placement of the ports). If you are trying to get something more akin to a subwoofer incorporated into this, then certainly ignore my comments. Good luck, -Tom

That's easy: A well-recorded Hammond B3 organ -Tom

Yes, I have a PAS3 driving a Dynaco 120. It is nothing special and also has some hiss and hum that you will hear over efficient speakers. Honestly, I think you would do a better if you got something else. Good Luck, Tom

Hello Mike, Since you seem to like the sound of the Krell, why is it that you are changing?. The Krell is a very good amplifier. Going to tubes will give a very different sound (a sound that some prefer). I would suggest visiting a local stereo store that has used/consignment equipment and demo'ing some tube equipment on your speakers first. Good Luck, -Tom

This is very sad news indeed. My thoughts and prayers go out to his family and loved ones -Tom

I agree with Bill: It is a shame. It does not take that much to move from a medicore system to a good sounding one. It takes 1) a goal and a path, 2) a bit of research to sort out the terminology, 3) a bit of experience/listening to enjoy the different aspects of sound that is available, 4) a bit of digging to get a sense of price & value, and 5) some energy on setting up the system and some modest treatment of the room's acoustics. To graduate from medicore to "pretty good" really requires planning but not necessarily a great deal of money. Nonsense like this is simply corrupting and distracting. I feel sorry for all the folks who are not able to enjoy the wonderful sound because of all the snake oil salesmen. My thoughts, -Tom

CAS, Interesting question. The sound is quite a bit different than a Klipsch. On the positive side ( and I am generalizing across a number of models). The mids & highs are clear &superb. The imaging can be incredible. The downside: they need a big amp capable of providing high current. They are difficult to position in a room (lots of tweaking - but is critical for the imaging and clarity). The bass can be weak. They do not always sound great (dynamic) when played loud (varies across models). These last two problems are magnified if the amp is not adequate. In spite of this I keep a pair of Maggies & Marti-Logans around the house. The do very well on small ensemble classical music, esp choral, baroque and early music. Some day I will get rid of them, but I have been saying that for a few years now. Good Luck, -Tom

Cultrain, Go slow on this. First, please do not assume that the fuse is reliable and will always blow quickly enough to protect the speaker. I think it is irresponsible for anyone to suggest keeping the K-Horn (esp with the drivers hooked up) in the circuit while you do your initial trouble shooting. Substitute a cheap speaker or a 10ohm 10watt power resistor ($1 at radio shack). Be systematic. Start at the amp and then work your way to up crossover (which is probably not the problem unless a wire/lead got loose). By no means leave the the K-Horn in the circuit for the initial testing! Good luck, -Tom

HF, Welcome to the journey. You commented that there was a perceived "bias" toward the Cornwalls. Well they are a good speaker, however.......... In my humble opinion the K-Horns are something special. Yes, there is a difference in price and the placement issues are critical for the K-Horns (although careful placement is important for all speakers). Take your time to find the the right deal. I was able to get my K-Horns for about $1000 used. This is about half of what they usually retail for (edit: I mean that used ones sell for). The price is mostly determined by finish & condition (model year to a much lesser extent). However, once you get away from e-Bay and instead scour local shops & classifieds you can find a deal (in part because they are so difficult to transport). The Cornwalls are typically around $600-800. Again, a deal can be found. In fact, thanks to a forum member I was able to get a pair of oiled oak CW 2's for $400 (I am still happy about this one). If you are patient, have the money, have the corners, then a K-Horn is the ticket. Otherwise, Cornwalls can also sound very nice. I am not objective, my opinion is very biased - hold out for the K-Horns..... Good Luck, -Tom

JJ, Congratulations on re-viving your Klipsh system! Dragonfyr has made some good points, think about them. You are absolutely correct in addressing the room issues first. Placement and room treatment (even if it's informal stuff like drapes, carpets & furniture) will have a far greater impact than components (Adcom is nothing to sneeze at) and cables (probably no impact anyway). The on-axis response is probably the the flatest, so do not worry too much about toeing the cabinets inward. Beside this will also swing the ratio of reveberant vs direct sound back toward the direct path. Depending on the room geometry, try systematically varying the distances from the rear & side walls. Use a CD that is well-recorded and that you are quite familar with. Go ahead and experiment and tweak. It is well worth the effort. Good Luck, -Tom

Jeff, My suggestion is that you first check e-bay under completed listings to get an idea what the NAD has actually been selling for. Sending the unit to get serviced can be expensive. The expense can sometimes catch people by surprise. Good Luck, -Tom

Bill, Congratualations on your success story. You raised many interesting issues. 1. frequently white spots can also be the result of alcohol on a wax finish 2. good point about the tannins in oak. They also react to any ammonia that might be in a cleaning solution 3. You had much better success with Oxaic acid then I have had. In my limited experience the solution was either too weak or way too strong. In which case it would do nothing at first and then whammo - too much bleaching. 4. I am also a fan of the Watco danish oil. Would love to see some pictures. Good Luck, -Tom

TPG, Congratulations on your new amp. 1. re: changing the bias - unless you really know what you are doing (and frankly, most folks would not), I would receommend NOT changing the bias - leave it at the factory spec. 2. re: "Passive" pre-amps - these are certainly an option if you are not using a phono. Please keep in mind two issues. The first is the relative input & output impedances of the various devices. The output of the CD should be relatively low and the input of the amp should be relatively high. If this is the case, then a well designed passive pre-amp will do fine. Second, the interconnect cable from the passive to the amp should be as short as possible. There will be a small capacitance in the interconnect. This capacitance increases with length. If there is too much capacitance, then you will inadvertantly create a low pass filter (1 / 2*pi*r*c) that may roll into the audio spectrum. This is simple physics and not "cable voodoo". Many are unaware of the problem however. 3. Possibility for a passive pre-amp: You can either build one yourself using an audio pot, or stepped attenuator, or transformer (some careful thinking is required about the impedance issues however). My suggestion would be to go check e-bay for an Adcom SLC 505 (they called it a straight line controller). They are no longer made, but you can get them for $50-100. They are well-built. IMHO its criminal how much some of these high-end audio companies charge for equivalent circuit. Good luck, -Tom

Dragonfyr, I appreciate your plan and I look forward to the fruits of your labor. Let me point out a few things which are meant to be helpful, although I suspect you have already thought about them anyway. For the case of simple frequency domain descriptions. Sure you can put in a boad band signal and get a transfer function of the unit. But there is so much contamination. If it is in an anechoic chamber, you get rid of room effects. But if it is a K-Horn you want some of the room effects, i.e., you want the corners. If it is a time domain description (and will I lump a number of techniques in here) then folks will have difficulty in interpretting the results ( I am not being snide, I am being realistic - in fact even a frequency domain based transfer function can be confusing to people. I have actually heard misguided people mention the "degradation" they heard with a phase shift at 17kHz...... another story). Measuring a speaker is interesting; however, the speaker is part of a system. The system includes the amp driving it, but more importantly, it includes the room that the cabinet is in. All speaker charactersistics are convolved with these two other components of the system. How does one communicate that and how does one give an idea about which effects are actually perceptible. I guess my concern is how to communicate the results to others (although perhaps this is not your prime consideration). Basically, how does an individual recognize which attributes/anomalies (transfer function, coherence etc) are important). Again, I will refer to my anecdote about the individual troubled by the phase shift at 17kHz. I am intrigued by your endeavor. If it is any help, although I no longer have access to an anechoic chamber, I might in the next year or so (with a 2 channel recording set up: analyzer with Bruel & Kajer mics etc). I do have K-Horns, Corwall 2, and a Hersey. If I do some digging I also have some software for both transfer measures (frequency domain) and Golay code -based measures. I am interested in what you are up to. Good Luck, -Tom

This really is an important question, seriously. I have many fond memories, where the action started with either Al Green or Marvin Gaye playing in the background. Ahh, to be young again...... -Tom

Double J , It looks like you have all the pieces. A pair of amps (a stereo amp or a pair of monos) and third amp (either a mono or one channel of a stereo amp) A pair of K-Horns and a Belle for a center. Or use the 3 Cornwalls A passive summing box (cheap and easily constructed). A nice big room I hope the above discussion has not dissuaded you. It really is quite simple to set up. After this, a few evenings for tweaking levels etc. Give it a try...... Good Luck, -Tom

Danny: The Cornwall works pretty well as a center between 2 K-Horns. I got a sweetheart deal on the Cornwalls - I could not resist..... The voicing is somewhat comparable and I did not have the money or space for full horn system (LS or Belle). The objection is that the radiating woofer (rather than loaded horn) is less efficient. It is this loss of efficiency that translates to increased distortion. PWK was concerned that mixing a Cornwall with K-Horns would corrupt the sound. The difference in efficiency (inversely proportional to distortion) is about 4.5 to 1. So the Cornwall, in terms of distortion, would be the weak link of the system. Although remember that the center is also turned down in level, so it is not as bad as first appears. Shawn: Perhaps we are talking about different things. I am referring to a center channel that is a summation of the L & R channels. There are schemes of using a difference signal (which I consider to be more of a gimmick to give a "lively" sound) or the steering methods that require a more elaborate circuit. I beleive this is what most of the other folks were talking about also. Given that, my comments hold true. My comments about the "tone" of these disscussions does not merely pertain to the current discussion. It is rampant across many of these threads. It is unfortunate since there is some real talent here and we could all learn a great deal about cabinet refinishing, crossovers, measurement, physics, history, trouble-shooting and recording etc. My comment is actually a tribute to folks like Al and others who continue to share their knowledge. Given the direction and exchange in some of these threads, I am surprised that they bother. Incidentally, the phasor analysis holds true (for a summed center) even when the listener is at the side. Such a phasor analysis was nicely derived and presented at an Acoustical Society of America conference several years ago (I don't think it was ever published however). Good Luck, -Tom

I amazed by the tolerance that Al is showing. It must be very frustrating. There are three points that have been made that I must comment on since this topic is near and dear to my heart (and at that the risk of me becoming frustrated). First is the simple fact that if I add two identical signals (same phase, amplitude, frequency - or from an identical noise generator) they will now add up to +6 dB more (SPL or voltage). If they are not identical in frequency or uncorrelated in phase or from another noise generator, they will add up +3 dB. There is no debate about this and please do not bring up some arcane example. Second is that the center channel should not be at an equal level to the L & R speakers. This is best understood by considering the phasors (I realize not all are familar with this, sorry). This is standard view used by folks like Ben Bauer and others when "stereophony" was first conceived and understood. If the level of the Center and Left speaker were identical in level then the resultant would be mid-position (half way between Center and left, or "halfway to the left"). . Importantly, this resultant is indistinguisable from the signal you would get by a single speaker placed halfway to the left (if measuring & using a 2-channel scope etc). Please notice that, this is essentially the same thing as a "phantom". A comparable statement can be made about the Center and Right speaker. Let me make the leap. If the center were at a comparable level as the L & R, then the sterophonic spread would be reduced. It would no loner extend from L to R, but rather from " half way left to halfway right". You have decreased the percieved angle in half. Yes, it would be the same as moving the 2 speakers inward. At a great distance, then the angle would become smaller (with a constant distance between the speakers) then the phantom center would be fine and no derived center would be necessary. At closer distances (larger angles) a derived center is helpful (it is difficult to explain why this is so). Regarding the possibility of excessive bass. Please see the first comment and also remember that these are very large wavelengths. There are standing waves and you will be exciting room modes. This also is a simple fact and not subject to debate or arcane examples that will get us off track. Personally, I would not use a high pass filter on the center channel. If there are problems in room acoustics that you are trying to clean up, filters are not the first weapon of choice and it would not be limited to only using them on just the Center channel. I am sorry if I am being pendantic. Over the last couple of years I have seen so many topics that have plenty of engineering, physics and psychoacoustics behind. Unfortunately, they are being discussed so poorly. I would love to to jump in and correct some of the confusions. Perhaps even doing so without a great deal of math. But I look at these antagonistic discussions where simple issues like phase delay, group delay, Haas effect, Fletcher-Munson curves, impedance etc can not be discussed without folks attacking one another in some weird pissing contest. I am done ranting now. Good Luck, -Tom

Interesting question. Some of my colleagues, looked into this one. The conclusion: No they do not work, but there are some interesting reasons why folks think that they do work. Good Luck, -Tom