PrestonTom
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Posts posted by PrestonTom
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Hello Daedalus,
You are in for a wonderful surprise. The prices seem very reasonable, the biggest factor is the condition and finish on the cabinet. Although some vintages sound different than others, the bottom line is that they all sound good.
The corners are a requirement, the baseboard issue is not a problem (this will become clear once you install them). The are various threads concerning some techniques about the placement and the use of pipe foam to seal the corner (and even false corners, if required). None of these are expensive.
One caveat is that the K-Horns are quite efficient. Three consequences of this; 1) the sound will be quite detailed and amazing, 2) you do not need a large amp, 3) the source, pre-amp, amp or receiver must be very quiet (any hiss or hum will be quite noticeable).
Good luck on your new adventure and take good care of them because you may find that 30 years from now you will still own them,
-Tom
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A good question, and many folks get confused on this.
The simple answer is NO!
With a reasonable distance, 16 ga is fine. The cable should not cost more than 30-50 cents/foot and the connectors a few bucks.
If you insist on spending more money or energy (and some people do insist for some reason), it is better spent on fine-tuning the speaker placement, acoustic treatments in the room (including re-arranging furniture, drapes, carpets, and the listening chair), having an aedquately sized amplifier, and of course, obtaining well-recorded CDs. These will have a profound impact on the sound, speaker wire will not.
However, the sensible approach means you can not engage in esoteric discussions about cryo-treating cables, breaking them in, or the directionality of the cables. That really is not much of a loss however,
Good Luck,
-Tom
(I get grumpy because there is an industry out there that capitalizes on on confusing people)
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Hello AncientDude,
An alternative to a pre-amp is a "passive pre-amp". If you are not familiar with this, the name is a bit misleading. It is entirely passive, basically just a switch and a pad (or step attenuator). The one I use is a Adcom SLC505. They are not made anymore, but are available on e-bay for less than $100. Since they are passive, no noise or distortion will be introduced and no sound will bleed through between multiple sources. Also, a used one will not require any servicing (other than some contact cleaner).
There are some caveats:
1) line level only as a source (no phono), 2) no tone controls (not a major problem), the interconnect between the Passive preamp and the amp must be short (the impedance of the preamp output and cable capacitance in the interconnect - if it is long - will low-pass the signal in the audio range), 3)for some odd ball sources (esoteric cd players) the input impedance on the passive preamp may not be 10 times greater than the output impedance of the cd player's output.
However, given the above this is as close to a "piece of wire" as you can get. Pre-amps costing $1200 do not make sense to me (unless phono is an issue), since they may have some degree of distortion, hiss, and hum.
I have been using this with my K-Horns, since their efficiency will reveal any inadequacy in an active component. That had been a headache that lead me in this direction.
Good luck,
-Tom
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Ditto what Michael said .... calm down, everything will work out okay.
Since you have gone through the birch ply, forget about a light stain. However, you have all sorts of options especially if you disassmble them. Before you take them apart, you need to look in the mirror, and ask yourself, honestly, do you have the aptitude and patience for a wood working project....
First option would be the piano black finish. This has been documented on several threads. The main issues are are whether you want to do a good job or a great job. In either case there are many steps involved, priming, sanding, priming, sanding etc. The finish is high gloss so any imperfections show up. You will need to educate yourself and then decide whether to use home vs automotive products (the later are better, but more expensive and may require the use of equipment that you do have access to). The results can be fantastic, but keep in mind: there are no shortcuts (it is really NOT a case of picking up a couple cans of spray paint).
The second option is to veneer the cabinets. This is actually probably easier for the DIYer (especially if you practice on something else first). The veneer may not be all that expensive - there are a number of choices. First you need to fill any voids and make sure the edges are not sanded round (they must be square and crisp). After the veneering, the cabinets will need to be finished (oil perhaps, I like the Watco products - it depends how much sheen you want). Again, educate yourself first, follow the directions, and take your time since multiple steps are involved. The results can be spectacular. There are also many posts on this topic.
If you are disassembling the cabinets, be careful and methodical. You will be re-gluing the pieces. Take plenty of digital photos before hand. You will need clamps and a square.
Again, you may want to enlist some help from a friend or relative if you are uncertain about some of these steps. However, on the bright side, there is every reason to believe that the cabinets will look better than new.
Good luck and have a look at the various threads on this topic,
-Tom
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Rudy,
I went through this myself, so let me share some personal experience.
The structure needs to have mass and stiffness in order to minimize vibration. The thickness of the plywood will not matter as much as the construction. The more bracing the better. Also using both glue and nails is better. If you want, you can get away with MDF rather than plywood. As far as sand to fill the voids, this will add quite a bit of weight, and I am not convinced that the results will be that much better with the added mass. These will certainly weigh quite a bit without the sand and you may have problems moving them. In my case, I used some insulation in the voids. However, to minimize and transmission of vibration from the cabinet to the corner, I did use pipe foam to seal the cabinet to the false corner, and the structure itself was on a rubber mat. This helped dampen vibration and prevented scratching the wood floor. As far as the height goes, I agree with the others: it is a design issue (as long as it reaches the top of the bass bin
It is worth spending some time considering the design aspect. In my case I dressed it up with paint & some wood trim to compliment the room (and hide a number of sins). Consider the WAF.
Good luck & the corners do make a difference,
-Tom
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Folks,
I am trying to understand the possible physics behind such claims.
I will buy the "possible" microphonic explanation (however I suspect that if you ran the numbers the effect may not be audible). I am stretching things, but is there any possibility that heat dissapation might be changed (again, running the numbers may show trivial differences).
I guess it boils down to physically meauring the differences (with and without) and then an old fashioned AB comparison.
This may be a false alarm, since my experience has shown that many people at Audio Asylum claim to "hear" lots of things.
I hate to sound grumpy; however, I beleive the biggest gains are made by concentrating your efforts on known quantities (i.e., well-recorded source material, room acoustics & speaker placement, using adequately sized amplifiers etc).
-Tom
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Hello No Disc,
The short answer is simply: NO
I am not sure what you are concerned about. If you are worried that the cabinet vibration will snap a solder connection, that is unlikely.
good luck
-Tom
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Mark, Thanks for for helping me out on the link (My brain was not engaged)
I'll try again.....
Hello Raptorman and Mick
re: use of pipe foam
Try this link. It shows an alternative false corner (that was heavily copied from others) and also has pics on how to attach the pipe foam. I hope it is helpful.
http://forums.klipsch.com/idealbb/view.asp?topicID=63165
By the way, simply screwing wood panels to the sides is not sufficient. At first glance it seems like a good idea; however, there will be problems. 1) attaching it to the cabinets will cause some irreversible damage, 2) it needs to be fairly sturdy and massive so that it does not vibrate. An approximation of that strategy had been done (I believe) for some theater systems. However for audio at home you really do need some version of a false corner.
Good Luck,
-Tom
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Hello Raptorman and Mick
re: use of pipe foam
Try this link. It shows an alternative false corner (that was heavily copied from others) and also has pics on how to attach the pipe foam. I hope it is helpful.
Good Luck,
-Tom
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David,
I forgot to mention (in case you were not aware) the top portion of the K-Horn will detach from the bottom (bass bin). It is held with a few wing nuts. That will certainly help when moving them. That is why GARYMD mentioned that they can be transported in a minivan.
-Tom
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Peter,
You are on the right track.
Sealing the horizontal portions to the walls/corners probably has the more noticeable impact on the bass. The effect of sealing the tailpiece was less noticeable.
Unfortunately at these lower frequencies, the room acoustics will dominate so trying to modify one cabinet and comparing it against the other will not give an adequate comparison (I will assume the room, furniture, carpets, drapes, doorways etc are not perfectly symmetric).
Good luck,
Tom
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Hello David,
So you are about to start the journey.... Good for you!
Actually K-Horns do come up on eBay on a regular basis. But there is little you can do about the shipping problem. Each cabinet weighs about 160lbs and, as you saw, they are big! You may need to rent/borrow a truck. The price you mentioned is certainly realistic. However you might be pleasantly surprised and find some much cheaper. I know I was able to get mine for about half price due to the size and also since the market is rather limited (not everyone can put these in their home or have an accomodating girl friend). As such, deals do happen.
One strategy is to place a "want to buy" in Audiogon in hopes that someone wants to sell theirs but has been put off by the hassle. It is worth a shot. The biggest issue on determining the value is their CONDITION (cosmetic predominatly, since the drivers are fairly robust) and also LOCATION (once you factor in the cost & effort for deleivery). Some will quibble about the version of the mid range driver (K-55 V vs M) and the crossover (A vs AA for the older models). However, those issues can be remedied and are not major problems (given the big picture: you are about to get a fantastic system).
Also, in my opinion, do not spend a great deal of worry about which amp and pre-amp etc to use - with one caveat, they need to be quiet components since the cabinets WILL reveal any hiss and distortion. However, they do not require much power. What you would need to worry about is whether your room is sufficiently large and has a pair of corners to place the cabinets into. If two corners are not available, then you would need to construct a "false corner". These are not always unattractive and can be simple to construct. There are many threads about this issue.
Speaker placement is a big deal, a much bigger deal than the other components (if they are quiet).
Good luck and let us know how your journey goes
-Tom
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Another difference (and I am not sure when it was introduced) is the use of rubber "flanges and gaskets" to help seal the K-Horns into the corners. There are a number of posts describing some fairly simple homemade versions using pipe foam. I tried this on my 1982's and the result was noticeable and pleasing.
Good luck,
-Tom
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Okay, okay, okay ... I just got sucked into this argument also.
I am firm believer in the simple, additive three-channel approach. It does require some fine tuning however. The center channel sould not be turned up much. All you are trying to do is give a bit more "firmness" to the center of the image. When the left and right are far apart, then the stereophonic center (phantom image) can be a bit weak. It is difficult to describe so I need to resort to words like "firm and weak".
A second advantage is that it will widen the sweet spot so your chair does not need to be in the exact middle. A third advantage was perviously noted in the reference to Snow et al's demonstations (the Bell Lab work) in that the image has more depth. A fourth advantage is that the center channel can (but not always) smooth out some the ups & downs in the frequency respones due to room acoustics (delay and add, comb filtering). I think when folks are disatisfied with the setup, it may be because they have the center turned up too much. This is where the fine tuning comes in. Some adjustment may be required in placing the center speaker also.
Do give it a try, even it is with a mock up (cheap speaker and amp). This will at give an approximation of the effect. If it is appealing, then do a proper job of it with a better speaker cabinet.
Good Luck,
-Tom
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I have also listened to my K-Horns along a 12 ft wall. The sound was fine. Remember however that ideally you would want the listening chair to be only about 6-8ft from the wall so that the cabinets and listener form a 90 deg angle (you are at the tangent from the face of the cabinet). This is an ideal (since the response is flatest when you are on axis). It appears that most folks violate this placement, anyhow. The K-Horns really do sound wonderful.
Let us know how it goes.
-Tom
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Neil,
I have also been intrigued by the idea of single driver systems. I am glad to see that you are carrying through on this stuff. I assume that you already know that there are a bunch of websites with pertinent info. If not, try a google search. I know you will find it very helpful. Keep us informed. I agree that is amazing how a proper cabinet/design can bring out the best in a modestly priced transducer. I suspect you are having a blast learning about this stuff also.
Good luck,
-Tom
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I have to confess that I was confused not PAULN. Of course 50 watts to 5 watts is a 10 db drop and hence "half as loud". My mistake, my brain was elsewhere.
-Tom
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I am confused by what PAULN is trying to communicate with that table of values.
Watts are physical measure of power. Loudness is perceptual atrribute that is certainly a function of power. But the relation that is listed is not a good description of the function that relates loudness to power.
I must have missed what you were thinking on this.
-Tom
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Hello Bruce,
This is a difficult circumstance for Barbara and you. I suspect the both of you may become overwhelmed by this. Please try and stay positive. Melanoma can be beaten! My thoughts are certainly for a speedy and full reovery.
All my best,
-Tom
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Gene,
It sounds like a nice big room that you have for listening. Go for it!
Being on-axis is best, which in your case would be 14 ft back (give or take). However, there will be a "hole in the middle" in terms of imaging. Since there is a wood stove in the middle, I will suggest using a false corner and move one of the speakers toward the center and then add a center speaker to the side of the stove.
This is sounding like a lot of money & effort... However, the center speaker need not be as high in quality as the sides (the K-Horns). The center is additive (left plus right ch) and it does not need to be turned up much in volume. Since it does not need much gain, you do not need to go overboard and try to get a Belle or a La Scala (if it is not a problem then go overboard by all means). I have had success with a Heresy cabinet (yes, I would prefer a Belle but that is not feasible at this point in time). Remember that the lower octaves will have plenty of energy from the 2 K-Horns. The center cabinet is "just filling in the hole" and making the phantom center a bit more stable and anchored. It is difficult trying to define the percept with words.
In my case, before I built the modified false corner (which does need to be unattractive). I jury-rigged a bookcase and sheet of plywood to mimic the false corner and borrowed a Vandersteen 2c (not much bass output but a decent midrange)as a mock center channel (I used a second amp and constructed a center channel box with a variable pot - there are various diagrams available). This was followed by listening with and without the center (at various degrees of attentuation and with various recordings). It does make a difference in providing the sterophonic image with a more solid panaorama. There is also a bit of depth provided - why this happens is worth another conversation. Since the effect does not require much gain for the center, the center speaker does not have to be on par with the K-Horns (yes, it is a compromise).
Anyhow, I have now totally re-arraged your living room, upset your wife, manipulated you into getting another amp and spaeker. I guess my work is done.
Seriously, do try the mock up to see if it helps - even it is just a radio shack speaker for a temporary center. This will give you first hand experience with what "the hole in middle" sounds like and it will give you an approximate idea of how it can be cured. If you like the result then by all means go ahead and do a proper job of it. Please let us know how this adventure goes and what your impresions are.
Good Luck,
-Tom
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James,
Happy Birthday. Many good things can happen when you are 15 - enjoy!
Take care,
-Tom
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Triode, Congratulations on the K-Horns.
I believe that setting both of them into corners will improve the sound. This is based on various "experiments" that I have performed in my living room over the past years.
I appreciate your observations that a single one in the corner is sufficient in some respects, but there are some other attributes you might want to listen for also. Yes, you are correct to note that the lowest frequencies have a very very long wavelengths. As such, the directionality is not always well defined. As others have noted this is why a single sub-woofer can be sufficient. In addition to the directionality, the very low frequencies may (or may not) have a more uniform amplitude respsonse if both cabinets were in corners. The mids may also be affected.
Here is my thinking: at this end of the spectrum the amplitude response is dictated by not only what the cabinet can deleiver but ALSO the room acoustics (the amp etc are typically not the limiting factors). The contribution due to standing waves will be dominant. To remind yourself of this, simply play a continuous low frequency or very low frequency tone through the Kilpsch. Now walk around room. Depending on how low the frequency (in other words how long the wavelength) you will notice spots in the rom that may vary by as much as 10-15 dB at frequencies as high as 500 Hz (an ocatve above middle C on the piano or abour 4 times the voicing fundamental of a male voice). At lower frequencies, the variation can be around 20 dB. This is an approximation since I don't know the specifics of your enviroment. If you don't have a meter, you can ballpark the measure by remembering that 10 dB change in the physical measure is about a "doubling" in the subjective respose of "loudness" . That is, does it sound "twice as loud" or "half as loud".
I have digressed... My point is that the standing waves can be minimized by adding a second speaker (in the corner). Unless you are unlucky, the standing waves from each cabinet (source) will not cancel and add at the same locations. The net efect will be that the sound (amplitude) may be a bit more uniform across location and frequency. You will probably also notice that the mids are bit better in the stability of their imaging also. Since each cabinet will have a similar geometry in back and to the side, so the 2nd and 3rd reflections are more similar. Again I am making some assumptions about the geometry and environment. The imaging on the mids will also be driven by whether you are listneing on axis (at a 45 deg angle to each cabinet). Yes the position of the listneing chair is important also.
One partial solution is to build a false corner or a even "half" a false corner. Others (including me) have posted & commented on various designs. Some can be fairly simple and acceptible (although surprising my girlfriend with flowers also helped). You might even want to approximate the corner prior to actual construction. I did this with a spare bookcase and a sheet of plywood. This will approximate the result and give you a better idea if you want to pursue the construction.
I guess my point is that it is just not the punch at the lowest frequencies that will be improved.
Good luck and if you pursue the "experiments" let us know your observations.
-Tom
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A very very beautiful job! Enjoy
-Tom
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Congratualtions on the new speakers. Enjoy them!
Yeah, you should probably surprise your wife with flowers also - she is being very accomodating.
-Tom
Does reversing polarity change music?
in Technical/Restorations
Posted
The issue of absolute polarity comes up every few years or so. Some manufacturers have capitalized on this confusion and made some money.
There are a couple of comments (which Gil mentioned also). Recording and reproduction is a very long chain of events. It is quite improbable that the absolute polarity was maintained throughout. Second, there may be some subtle differences using some very specific waveforms - one of these is referred to as as the "Wood effect" (I would have to dig up a reference on that).
Unfortunately, the discussion on polarity effects gets smeared because folks confuse left & right channel polarity (a big effect) and phase or polarity reversals between sections of a crossover (sometimes necessary and it may or may not be a problem).
Although I am fairly negative about whether absolute polarity has an effect, I do sometimes wonder in a mechanical transducer (either a mic or speaker), would the distortion differ (either in degree or type) with regards to whether it was moving inwards or outwards. Again, if the transducer were in its linear range there would be no problem; however; since there is a mechanical suspension etc, the direction might make a difference. This of course it simply speculation. The real question is whether a listener can actually discriminate between the two in an AB comparision.
-Tom