garyrc

Well lets see (I happen to have a chart): If you want very realistic dynamics, and if your room has average liveness (I know, I know) and if you listen at about 13 feet away (or less), you should be able to get the THX/Dolby instantaneous (1/4 second or less) peak level of 105 db at your ears above 80 Hz at 16 watts RMS with a bit of headroom to spare. This assumes, that for bass below 80 Hz, you will have a powered subwoofer (although you may be too much of a purist, given your tastes as indicated in your post). Horn subwoofers may be cleaner and faster than the typical. The sub should be capable of 115 dB. If you don't use a sub, then you may want 10 dB more SPL available through the Chorus below 80 Hz -- although you may never use it -- requiring 160 watts. Now, a lot of people get away with 4 or 5 watts, or so, but I don't see how that can provide full dynamics. If you don't want full dynamics, 5 watts would give you something like 100 dB at the MLP. YMMV.

Timshel!

I'll have to give this a look. I just found out I'm more Scandinavian than anything else, based on DNA. A big surprise!

Back in the day we always used roach clips because a high roach is easier to deal with than a high alligator, and if they go to sleep the roach is easier to move.

@Curious George Since I have a Klipschorn AK4, I evidently have a polyswitch. In what ways are they better? Do you have any articles to recommend?

I'm curious about the dynamic range of cymbal crashes at the frequencies that reach the tweeter. In the case of Klipschorn AK 4 & 5, perhaps others, that would be Xover at 4,500 Hz rolling off below the Xover at 36 dB per octave.

Questions: Is 10 dB 10 times, when dealing in watts? I realize you were looking at volts at that point. On what speakers did you do these measurements? Khorns? The overall signal, up to maybe 2K Hz might hover around 1 watt (95 dB at 13 feet away, in my ~ 4,300 cu. ft. room with Khorns) but would even a cymbal crash produce a peak of 1 watt in tweeter range, above about 1 octave below crossover (2.25K Hz -- 36 dB down in the AK4 & AK5 crossovers) into my Khorns? The figure we often hear is that "the treble" is 20 dB down in orchestral music (electronic and other "non-acoustical" music excluded). Wouldn't that exactly offset the 20 dB dynamic headroom quoted above? Subjectively, when I disconnected the woofer in my old JBL 030 c.1960 CE, cymbal crashes through the tweeter only (Xover @ 2,500 Hz) sounded like someone emphatically making a "sheeeesch" sound with their mouth (but a little more sfz). I measured it at about 92 dB @ 3 feet. O.K., is "the treble" a full 20 dB down? Maybe, maybe not. Let's look at some possibilities: If the treble above tweeter crossover is 20 dB below the overall level of 95 dB =1 watt (Khorn in my room) overall level for the full orchestra, that would be somewhere around 0.0052 watts into the tweeter, when the orchestra is churning out additive and interactive combined fundamentals and lower and medium harmonics (below tweeter Xover) of 1 watt, or 95 dB. To play with the big kids, at THX/Dolby full scale for peaks (20 dB dynamic headroom over their arbitrary "typical" or "nominal" SPL of 85 dB) of 105 dB at the listening position for the full orchestral sound (not counting frequencies that would go to a subwoofer), this would be 10 watts (105 dB peaks) for the music as a whole, and still only 95 dB (1 watt) for the tweeter. If the treble above tweeter crossover is only 10 dB below the overall level, the tweeter might get 10 watts, the zener diode would clamp down, and distortion would result. 5. Can we substitute another component for the zener diode that would protect the tweeter, but not introduce distortion?

I assume Boltzmann and Ehrenfest each died passing a perfect gas, and that the presence of a human observer would have made no difference whatsoever in their state.

True, originally stardust. But some do chase the dust in the wind. "I have seen all the things that are done under the sun; all of them are meaningless, a chasing after the wind ... I applied myself to the understanding of wisdom, and also of madness and folly, but I learned that this, too, is a chasing after the wind ... " [Attributed to Solomon c. 940-ish BCE] And so it goes, until he gets to: "To every thing there is a season, and a time to every purpose under the heaven: · A time to be born, and a time to die ..." Etc. And, as we might say today, "Go with the Flow," and "Play it as it Lays."

The Dawn of Everything: A New History of Humanity Graeber, David (& some other guy -- the book is not in front of me) I started with H.G. Wells Outline of History in elementary school, loved the line drawings showing the relative sizes of Brontosaurus and man, and the treatment by Wells of the "penniless preacher from Nazareth who was the center of history" [quote is approximate], dabbled in Will Durant and Toynbee, and now it is time to look at one more take. From another angle, I read several books on cosmology, most recently The Grand Design by Hawking and Mlodinow, but I still don't really know why there is something rather than nothing. What are we, and what makes the other great apes avoid murder, war and politics more than we do? And, by the way, what is all this?

Home Theater, Library, Music Room. 2 Klipschorns with K-401 mid horn upgrade, and AK-4 Klipschorn upgrade. Modified Belle Klipsch center channel with K401 horn in an enlarged hi hat, flush mounted, behind AT wall fabric, buried in the wall between the Khorns, 2 NAD 150 wpc stereo power amps, Marantz AV7005 AV processor, Heresy II surround speakers driven by 1/2 NAD C-272 and a Yamaha 135 wt amp, OPPO BDP-93 CD Universal player, Klipsch RSW-15 subwoofer, Panasonic projector, 130" true width 2.35:1 projection screen (141.3" diagonal). musicc room pics & text.pdf Some pages have large blank areas -- keep scrolling down until you see my signature, Gary. Thanks. music room PDF.docx

Since he is mentally "pretty good," I think he should decide what equipment is to be sold -- unless he already has. Will whoever sees him give him our regards and thank him for his years of wisdom on the forum?

Yes, it works, but PWK underwent a slight mind change. He felt that it is a little better to have a fully horn loaded center channel, i.e., a La Scala or a Belle Klipsch, rather than a Heresy or a Cornwall, because the perception of a whole array tends to sound like it has almost as much modulation distortion as the speaker with the most modulation (Doppler) distortion, i.e. the highest number of harmonically unrelated sidebands. So in a three speaker array, the center speaker should have just about as low modulation distortion as the flanking speakers. This is in one of the Dope from Hope bulletins. I agree with you, @Tom05, on simulated or derived multichannel. I really like Dolby PL II Music (didn't think I would) for two channel recordings. The 5 channel simulation helps "open up" the sound, more so on some recordings than others. But, even better is SACD multichannel (mostly classical and jazz). Obviously, your player has to be able to decode SACDs. Contrary to the continuous requiem for SACD we hear in the audio press, there are still many classical and jazz SACDs out there. Although we stream movies, we haven't selected a music streaming service yet ... a big project. N.B. for anyone considering a projector and screen: our 130" (true width, not diagonal) "acoustically transparent" Seymour roll down 'scope (2.35:1) screen is immersive, sometimes thrilling, especially with Blu-rays of 70mm films, meant for huge screens in cinemas (Lawrence of Arabia, the original Around the World in 80 Days (1956) in Todd-AO, with a few shots using their 128 degree camera lens, How the West Was Won in Cinerama's 145 degree view (available in Smile Box), films in D150, etc., can't wait to try The Hateful Eight). I know it's expensive -- it took us about 15 years of planning, saving up, building, etc. -- but it is a joy! We eschewed a cinema-like home theater, in favor of multi-purpose. It's a sort of library-projection room-music room. We use the same Khorn system for our music and our movies. Wish I could attach pics of the whole room, but the 2 MB limit ... if you'd like to see the whole room, see my post responding to @jebartist of December 6 -- the attachment on that post actually worked without being truncated. What Cinerama looks like in our home theater.docx

Dear @wvuvt1, Welcome to the forum! The Yamaha really is only 100 watts per channel, RMS . It is safest to go by the RMS rating. According to Yamaha, Minimum RMS Output Power (8 ohms, 20 Hz-20 kHz) = 100 W + 100 W (0.019% THD). I don't see whether that is with both channels driven -- maybe it is specified somewhere else. It is preferable for the power spec to be with both channels driven, so the power supply is properly stressed during the test. Nearly all amplifiers will produce instantaneous peaks at a higher level (e.g. 1 to 3 dB higher) but only for a moment. The Emotiva, according to Emotiva, has Power output: 300 watts/channel RMS into 8 Ohms; two channels driven. I don't see whether that is the figure from 20 Hz - 20Khz. It should be, but I'd guess that it is, since manufacturers tend to fudge their specs less with separates, like power amps. Beware, though, if you find the power rating is at 1K only, as is occasionally done by some. You have a BIG room. You don't say how high the ceiling is, but, if it is 8 feet, you have a 4,800 cu. ft. room, 1.13 times as big as mine, so I'll take that into account. Dolby and THX, for a concert hall or theater, require the ability to produce instantaneous peaks of 105 dB above 80 Hz, and 115 dB below 80 Hz. Because of early room reflections in rooms our size, which make the sound seem louder than it really is, Dolby/THX says we can get along with peaks that are 5 dB less, so 100 dB, and 110 dB below 80 Hz. I assume you are not using a subwoofer. On Fanfare for the Common Man, The Great Gate of Kiev, the finale of most Beethoven or Mahler symphonies, I can measure 100 to 105 db, C wt., "fast" rather easily, a few times even more. Sometimes people don't hear very brief clipping, which, I assume might still blow a tweeter. The Klipsch RP 8000 F has a sensitivity ("efficiency") of 98 dB at 2.83v (1 watt into 8 ohms) at 1 meter, not at listening position! A Klipsch engineer (not Roy) told me that would be the sensitivity in the "typical" living room (rooms provide room gain and boundary gain). To make the sensitivity more like the AES standard, he advised subtracting 4 dB from most Klipsch sensitivity ratings. So, to be conservative, lets use 94 dB as the sensitivity. I happen to have a chart that lists dB produced and watts needed for that Sound Pressure Level at a listening position 13 feet away (instead of the sensitivity spec at 1 Meter), and I adjusted it for your room size. For medium level music, not peaks, you would need less than 1 watt. Let's say the Emotiva will produce peaks 3 dB over the RMS rating. To get 110 dB peaks, you might need peak power of 250 watts, or 125 watts RMS. The Emotiva is looking good right now. Read reviews of both amps. Ask @Shakeydeal what he means by "little finesse." Compared to what? The Yamaha? Listen to any amps you are considering, if you can. [my bolding, italics and underline] You may know this, but speakers don't produce electrical wattage (unless they are "powered" like a subwoofer, i.e., contain their own amplifier). The RP8000F is a good, but unpowered, speaker; most speakers are unpowered. Unscrupulous dealers -- often big box stores --may say a given speaker is a "150 watt speaker," or a "600 watt speaker," etc., but there is no such thing. Some sales people may be mistrained to (unknowingly?) speak this way to make people think a speaker is powerful. A speaker is a transducer that changes electricity into sound. The output of a speaker can be specified in acoustical watts but almost never is; just know these are not electrical watts, and these are not what dealerships, manufacturers, or big box stores mean. The Sound Pressure Level in decibels is talked about in two ways by manufacturers: Sensitivity ("efficiency")-- see above, and Power Handling (your speakers have a power handling of 150 watts/ 600 watts peak. Once Paul Klipsch was asked what manufacturers meant by "Power Handling." He said, "Probably not a lot."

Even I can't open them now. I'll work on it. Here, try this: Here is what the K77s in my Klipschorn AK4s above 4.5K (Xovers) look like after room treatment and Audyssey Flat. The main divisions are 5 dB. As you can see, the sweep crosses the 0 line at 12.27K, and the top of the curve is about - 4db at 17K Hz. If I want it (on certain recordings), adding 3 dB with a treble control, provides a slightly higher bulge below 12.27K and brings ~~ 15K to almost flat. For the below, I wish I had the original documentation -- maybe someone else does. Here are three K77/T35s. Look only above 4.5KHz, to match use in the Klipschorn AK4 or AK5 and the lower cut-off of the @Dave MacKaygraph. The RED plot is from a Klipschorn "of unknown history," IIRC, the others from separate, detached K77/T35s, all without EQ.

P.S. I listen mainly to classical music, jazz, folk, film music, etc; full orchestra sounds great on most CDs, SACDs, DVD-As, Blu-rays, etc., but when a friend brought over Springsteen, it sounded pretty terrible. Later I tried again, and it sounded bad on any speaker in the house, including, at the time, Khorns, Belle, Heresy II, ADC, JBL, etc. Maybe I just don't know what Springsteen is supposed to sound like.

PLEASE IGNORE AND MOVE FOUR POSTS AHEAD FOR ANOTHER TRY!

Sad news, just in Dec. 23: Joan Didion has died.

At the training studio at SFSU (in the 1970s) 3dB correction in the treble was way too much of a change to be a JND. In music with a lot of midrange and treble, through Khorns, I sometimes think I can notice a 1/2 dB change; I can definitely hear a 1 dB change. Google produced this: "A useful general reference is that the just noticeable difference in sound intensity for the human ear is about 1 decibel. ... The jnd is about 1 dB for soft sounds around 30-40 dB* at low and midrange frequencies. It may drop to 1/3 to 1/2 a decibel for loud sounds." http://physics.gmu.edu › ~dmaria › sound › DB *For music, moderate level is 75 to 85 dB, loud is 90 to 100 dB, with instantaneous peaks (perhaps 1/4 to 1/3 second, or less) up to 110 dB in a living room; the leading edges of some peaks have been measured as high as 120 dB in a concert hall, close up.

We just saw the Joan Didion documentary, so I'm reading her novel Play It As It Lays. Just started, but as interesting as always. As for her nonfiction, The Year of Magical Thinking may be the saddest book I've ever read, but strangely cathartic. The collection The White Album was excellent, also, but I think she was a little hard on Bishop Pike.

I use a Phantom channel center (no center channel) on our extra TV in the bedroom. While it works fine, the Left and Right channels are only about 40" apart, and we are 3 times as far away as they are apart. Just for ducks, we tried a 2 channel front array with no center in our home theater, with viewers an average of 13 feet away, with mains' tweeters about 17 inches from their respective side walls, in a room 16.75 feet wide. Someone sitting in the center seat, pretending to use the proverbial head clamp, got an acceptable center image with dialogue centered, but that was not true for any other seat. With a center channel and speaker, dialogue was well placed even from the side seats. When you say that most Center Channels don't sound as good as the mains, do you mean that the Center Channel speakers sound inferior to the mains, or that the audio signal fed to the Center is, itself, inferior? I certainly agree that many CC speakers are worse than the mains, in fact the Achilles Heel of Home Theater. My impression is that the CC signal is usually about as good as that sent to the mains, with exceptions occurring rarely. The OP has Klipschorns that look like they are even more widely spaced than mine, so I would predict that he needs a Center Channel.

Good. I stand corrected. That is another 5 inches saved.

It seems that the two that would blend best with the Khorns would be either the La Scala or a used Belle Klipsch. I don't think the timbre match could be any closer, short of cramming a Klipschorn in there (and changing what looks like might be your roof line). Both the Belle and some La Scalas (not the I) have a removable top hat, so the shorter bass-only section, perhaps, could be put below the TV screen, and the midrange and tweeter mounted above the screen. There would be a few ifs, ands, and buts. The K401 or K400 midrange horn and K55 driver are just under 28" long, I think. Perhaps it could be set back into the wall, thus gaining a few inches. The mouth of that horn needs to be firmly attached to a flange, normally the front baffle board of the top hat, to avoid vibration (ringing) of the horn. So, we might be looking at a custom, built-in, partial top hat above the TV. This might be too much of a wrench to deal with, but if done, I would predict that it would be worth it. All I can say is we have Khorns and a totally hidden, flush mounted, Belle center channel, with the shorter Belle midrange replaced by a K401, with the whole thing buried in the wall and beyond (see attachment), and it sounds great, and, partly because we crossover to a sub at 40Hz (after many experiments), we usually can't notice that the Belle sounds any different than the Khorns. musicc room pics & text.pdf Some pages have large blank areas -- keep scrolling down until you see my signature, Gary. Thanks.

Maybe Micallef and Reichert should have reviewed the Klipschorn A6 for Stereophile. At least they might have not raised up the Khorn on a dolly, outside in a driveway to measure it.

How loud is loud? Have you measured the SPL with a meter set on "fast," at "C" or "Z" weight (to measure the bass as well, instead of rolling it off the way "A" weight would)? On your record, one channel (the one the distortion stays with) could easily have much more bass than the other one. It's easy to assume that 20 watts is enough, given the high efficiency (sensitivity) of Klipsch speakers -- I make that assumption -- but you are turning both the volume and the bass up (I don't blame you!). So, lets go through the steps. The sensitivity of the Heresy IV is specified by Klipsch as 99 dB in an average living room [not in an anechoic chamber. (A Klipsch engineer -- not Roy -- said the sensitivity of Klipsch speakers in an anechoic chamber is about 4 dB less). Is your room average in liveness? How far away do you sit? How big is your room in cubic feet? In the USA, typical is about 3,000 cu.ft. Indoors, one loses about 3 dB for each doubling of distance (not the 6 dB one loses outdoors). So, if you sit 13 feet away (~~4 meters), that's 2 doublings, so you would get 93 dB at 1 watt. 1w - 93 dB 2w - 96 dB 4w - 99 dB 8w -102 dB 16w-105 dB 32w-108 dB (with a bit of dynamic headroom for instantaneous peaks). Dolby/THX figures peaks of 100 dB full scale in our reduced size rooms (compared to a big hall), but that is above about 80 Hz. Below 80 Hz, a separate subwoofer is allotted 110 dB in our rooms. If you are cranking it up that far, with no subwoofer, you might be needing about 53 watts on instantaneous peaks (an amp rated at 26.5 watts if it has truly excellent headroom)! So, could it be just barely clipping, or just barely overheating the tweeter or midrange voice coil, as clipping is wont to do? Addendum: One more thing to consider. Is your last name Winchester? In California there is the Winchester Mystery House. The place is full of ghosts.