Chris A

Interesting...Toole recommends placing subs all over the room...[:|] I think that Toole was trying to get relatively level low bass response all over the length and width of a potential listening area - something that I don't even try to do. The effect of putting them with your fronts so that the bands above ~50 Hz will coincide with the same location--due to directionality of human hearing--is something to consider also. Trades, trades, trades... Chris

From http://forums.klipsch.com/forums/t/22533.aspx?PageIndex=2:

http://en.wikipedia.org/wiki/Extra-tropical_cyclone#Historic_storm

Actually, there is a JAES paper that describes the performance of subs in various locations of the room, AND with different listening positions (1999, "Subwoofers in Small Listening Rooms" Tomas Salava, ETOS Acoustic Ltd.) The bottom line: "...This author...affirms that placing subwoofers...in corners is sonically advantageous especially in small rectangular rooms [i.e., home-theater-sized rooms]. The reason to place subwoofers in corners, especially in small listening rooms, seems quite simple: all the room modes are fully excited and can be transfer-active. The room gain (as some authors call it) obtained at lowest frequencies by this placement can be much [more] easily and conveniently equalized (if necessary at all)..." Chris

Linkwitz did the math for closed box woofers - and it's pretty high...too high for me to ignore the effects of microphonics, IMHO, without considering the discrete devices used (especially film caps). Chris

Actually, the problems that I have with reception are with channels 8.x and 4.x. IIRC, channel 8.1 is actually the lowest frequency that is broadcast. The higher frequencies are much easier to get. Chris

I used the highest gain in-room antennas that I could find - and they weren't enough. I finally broke down and got a Radio Shack Yagi antenna that did the job in the attic, but not after having to move it around a bit. Hope you don't have to do the same thing, but it's nice once it's done: no outages - no monthly bills. Chris

Here is the equivalent plot for the K-77 tweeter. Divisions on this plot are apparently 2 Khz. I don't see a lot of solid overlap between these two drivers/horns.

I just found the K-55/K-500 Horn FR.

I'd say that a direct radiating sub is probably your best bet, based on the size of room and type of speakers. A good direct radiator sub of fairly large diameter driver (12"+) will fit the bill. Obviously, you're looking for low frequency output below 20 Hz - and that is usually found with acoustic suspension speakers that are EQed to boost their low end. The larger the driver total area (including multiple drivers), the lower the distortion... The SVSs mentioned here will do, but also other sub manufacturers have good units.The key is that you can pressurize the room your size with low bass, especially if you shut the doors/windows. Placing the sub in a corner will couple it to the room better and increase/smooth it's low frequency performance. Chris

Horn-loaded subwoofers fit that bill nicely. However, they can be the size of a small refrigerator or of a large bookcase, depending on whether they are of conventional horn design or of tapped horn construction. Most can be do-it-yourself, but some are also available commercially, albeit at much higher price due to the labor spent building the horns (one reason why you usually don't find horn-loaded subs at hi-fi shops). What size room (dimensions) and what type of speakers are you planning on? Chris

[H]You'll get used to them...

My XTi's roll off by themselves, but Danley recommends a 15 Hz, 24 dB/Octave Butterworth high pass. I don't think that you'll have any issues not using the high pass - you'll hear the drivers bottoming out before other bad things start to happen... Chris

http://en.wikipedia.org/wiki/Microphonics I think that most passive crossovers are better outside the speaker box than inside...ever wonder what the SPL is inside an acoustic suspension speaker (like the Heresy)? The Khorn, La Scala, and Belle crossovers are effectively outside the box. Cornwall, Forte, Heresy, Chorus, and most of Reference line is inside... Chris

Most def...yes.

I think that this is very key - and many people have fallen into the thinking that they need a "music sub" and/or a "HT" sub - something that says to me that they aren't used to hearing good infrasonic bass speakers (i.e., horn-loaded subwoofers). I leave my subs on all the time - because it doesn't sound right when I turn them off... Chris

Sorry - insert "Tubas" for "IBs".

Not me. Note that dtel and Rudy81 moved their driver access ports/connectors into an easier-to-build spot (i.e., just like the Danley DTS-10 access ports). Note that Hoffman's Iron Law applies to subwoofers as well. The use of conventional folded horns give you as much as 10 dB of increase in output over direct radiators (i.e., using the same driver and the same input power), or said another way, horn-loaded woofers will have -10dB the distortion of direct-radiating woofers, given the same driver/power (...a quote from PWK). Tapped horns have higher relative output over conventional folded horns by as much as 3 dB, i.e., twice the acoustic power output. The real issue is "how much room are you willing to fork over to your subs?" In my case, I'm not willing to give up the floor space and an available corner that is required for the IB Tuba horn geometry or other conventional horn-loaded sub. The SPUDs are very compact and their form factor is very easy to work with, in fact synergistic with, corner-loaded Jubs. My SPUDs also acoustically integrate seamlessly with the Jubs - a cannot tell when the subs take over from the Jub bass bins - they sound like Jub bass bins. That means: "...the subs are always on-- HT or music...". The SPUDs also fit into my room, and their cost is more than an order of magnitude lower than any commercially bought sub approaching the SPUD's output. Chris

Extract from "Dope from Hope", Vol. 2, No. 12, (10 November 1961) Most important, however, is the fit against the comer. Whenever there is a known performance loss in the 250-500 cps range, the flap seals are suggested. Back in 1948 we were aware of an interference effect from the right and left sides; a 40° off-axis microphone placement under anechoic conditions (such as an inside comer outdoors) results in a deep response dip at about 280 cps. Also under similar conditions with a hard floor or ground there is an interference between the horn radiation and its mirror image below ground, and a microphone at 4-foot height will show a dip at 350 cps. These are typical standing wave phenomena; in spite of such effects the system radiates power and does so smoothly if all precautions are observed. In fact our claim '10 dB peak-to-trough ratio' can be bettered by several decibels. We recommend attention to seal at the corner; the flexible gasket sheet or a felt pad or other sealing means will reduce the peak-to-trough ratio as much as 7 decibels Paul W. Klipsch, Editor KLIPSCH and ASSOCIATES Hope, Arkansas

I don't believe that this will be an issue: if there were to be any significant changes to this forum (e.g., new posting rules, user censuring, increased thread locking due to adverse information, etc.) with the intent to suppress user voices, I believe that there would be an independent forum that would crop up very rapidly, especially if forum changes happened too quickly. What do you think? Look at other forums for examples.

Netflix advertises many "HD" movies in their menus - and I've watched some of those. They're very good--and in 5.1. Chris

Mike, Perhaps it's appropriate to point out that active crossover setups, which couple drivers to amplifier outputs without the need of passive networks, make a lot of sense. Active crossovers avoid many of the issues discussed here that we see with passive crossovers and their balancing networks which shift impedance up or down to achieve relative balance of the speaker's drivers. Woofers (even horn-loaded ones) take the most power due to the fact that they're almost aways the least efficient acoustically - usually by 6-10 dB or more relative to midrange and tweeter compression drivers Active crossovers allow you to bypass essentially all of those problems, providing more available power to your drivers (i.e., power isn't soaked up by the passive crossover networks), providing better driver damping due to the direct coupling, and protecting your tweeters from woofer-power-induced amplifier clipping. There is usually a decrease in reproduced distortion due to the reduced band of operation for each amplifier channel and reduced heating of networks. I believe that the reason why many people use passive networks today in higher-end consumer speakers is due to buyer familiarity rather than performance. The pro-speaker market made the shift to actives some time ago especially with the appearance of quality affordable active crossovers. Just my $0.02 Chris

Dean, Are you basing that on first-hand experience? I don't hear anything out of my Dx38 in terms of noise.

Sorry about that - I couldn't resist... Seriously, PWK was pretty adamant about no gaps under his speakers, so they should be on the floor (for that matter, this applies to all Klipsch Heritage speakers). Secondly, the Khorn needs to be centered left-to-right in the corner such that the two horn mouths on each side are the same size. If they're not in the corners at 45 degrees, they don't sound right. I have mine in corners with the open-cell refrigeration pipe insulation on the tail piece and on the top of the bass bin to seal the tops from the bass bin. This helps quite a bit - and the most important seal is on the tailpiece. It also helps to keep marks off your walls... Chris

What a guy!!!! Richard, you're a gent... Chris