Chris A

KB = Klipschorn - Model Type B, "collared" BB = Birch Black 17-993700 = (Can't decode this - try looking closer at the serial numbers - then use this to decode: http://forums.klipsch.com/forums/p/103886/1048788.aspx#1048788) Chris

I'm sure that many here will encourage you to invest in them for that room. If it were me - I'd invest in the La Scalas and an active crossover so that I could tri-amp them. Why? There is something known as "minimum convergence distance" and it is on the order of 7-10 feet for the non-time-aligned La Scala. In order to correct for the time misalignment of the La Scala drivers (tweeter needs to be delayed relative to the midrange, but with different delays to each other to time align with the bass bin). This would significantly reduce that minimum convergence distance. What would it sound like? Extremely good, even with the low ceiling and the 7' listening distance. The clean horn-loaded bass will be a step up from the Chorus, IMHO. Chris

The linked reference makes several points - one of which is the issue at that time(1984) with digital recording techniques using the then-new CD format. I believe PWK was talking about recordings made at too low level that was suppressing the background noise level at threshold conditions.But also note that he was talking about relative peak-noise level for real environments - his answer was something more like 50-60 dB as that which exceeds any typical recording environment. That comment was right on the mark for the conversation about Dx38 noise floor, IMHO. Chris

Actually, that comment was meant to imply that the SPUDs could simply be placed in the corners and the Klipschorns (Khorns) placed up against the SPUDs along the front wall.The advantage of this arrangement is that the SPUDs and Khorns mutually benefit: 1) The Khorns benefit in being moved slightly out of their corner into the room in order to have "clear air" between the left and right speakers for superb imaging performance. The SPUDs act as one half of a false corner to close the gap between the Khorn and the front wall, and the SPUD cabinet very rigid (a good thing for the Khorn bass performance). 2) SPUD performance is significantly increased by being placed in the corner with the mouth of the SPUD next to the floor and the side walls - fully in the corner. The space between the Khorn and the SPUD forms a partial extension to the SPUD's horn length and gives you flat bass performance to a very low frequency (~17-18 Hz depending on the stiffness of the outside walls). It's easiest to use a HT AV processor to provide a subwoofer output signal to the SPUDs (simply split the AVP's sub out signal to two or four amplifier channels - to power the two SPUDs). I find that this works also for 2-channel operation, but audiophile purists that want to use separate preamps for HT at two-channel operation could simply use an active crossover like a EV Dx38, DC-One, or other unit downstream of their preamps to provide full-time SPUD performance.It really makes a difference in both HT and two-channel operation with the Jubs in my room (see profile). Chris

The Belle is a prettier and wider/shallower La Scala (the Belle only 18 5/8" deep instead of the La Scala's 24 1/2 " deep) . It fits the room between Khorns a little nicer because of that, but otherwise the bass cutoff frequency (Fc) is essentially the same as the La Scala's. However, the La Scala apparently has slightly better bass performance other than Fc. Both designs were developed to be used either in a corner or along a wall, just like the Cornwall.Chris

http://www.diyaudio.com/forums/showthread.php?postid=1698483

Well Mike - I guess that I don't know anything... Chris

Actually, I'd recommend using the SPUD in a corner, not as a riser. And note that the total cost of materials for the SPUD is about $200 as a DIY, even using Baltic Birch ply. If you can build it, than I'd recommend building two - they really don't take a lot to drive them in terms of Watts/channel. The SPUDS have a nice form factor to fit behind your Khorns, thus allowing you to move the Khorns forward about a foot and in the process potentially getting much better stereo imaging from them. Direct radiator subs typically take a lot more amp Watts to drive properly. Chris

I agree with Richard (Coytee) - a horn-loaded sub like the DTS-10 (Danley - and check Audiogon for a pre-owned listing), TH-SPUD (DIY or Danley), or perhaps a Tuba design (Bill Fitzmaurice's DIY design) would probably be your best bet in a room of the size that you quoted. The problem is that most direct-radiating subs just cannot produce the quality and quantity of low bass that you will need to complement your Khorns in a room that size. How high is your ceiling? Chris

OMG!!!! []

I agree with the statement in principle but note that many people who have been associated with this forum do not qualify as "average public". My concern is that someone here might misunderstand the statement to mean "too hard for me" and nothing could be further from the truth, IMHO.If speaker manufacturers started to sell their mid- and high-end speakers with outboard active crossovers (or recommending third-party units) in the consumer marketplace, then I think people would use them. I believe the real issue that stops most manufacturers is "...we've never done it that way before...", and a buying public that hasn't been educated on the advantages. High-quality passive crossovers for high quality loudspeakers probably cost a lot more than matching-quality digital crossovers, and the digital crossovers are much more immune to drift over time. Why don't most consumer manufacturers use balanced cables and XLR connectors (which are superior RCA cables) - is it only cost? I doubt it. Space constraints? Well, no, not really. "We've never done it that way before?" Probably, yes. I think many people on this forum miss this point - and they're not looking at the Klipsch Professional line of products. Too bad - "there's no accounting for taste". [] Chris

I asked a related question last year on another forum about that exact subject. I didn't get a very good answer, IMHO. Chris P.S. see the following -- http://www.sweetwater.com/store/detail/ODL312/

Wow - you must have a really big room...[] Enjoy! Chris

(With pre-apologies to Mike B. if I appear to be unrepentant on this subject): I will here note that I've never seen noise figures on turntable/record inputs that exceeded 70 dB(A) of noise floor. The inherent EV Dx38 figures that are being bandied about here (90 dB- what scale?) are at least 20 dB better than records and significantly better than analog reel-to-reel tape (w/o noise reduction techniques). Why wouldn't we be talking about vinyl/turntable noise figures here for those folks that still use those devices on a regular basis. I'd hazard a guess that one of the least objectionable forms of distortion is noise floor--if it is very low as it is here--even if that noise floor is modulated at very high SPL. PWK once commented on the unnaturally "ghost-like quiet" in digital recordings of the 80s. By way of analog comparison, flat screen TVs and digital camera contrast ratios cannot begin to approach the ~13.5 f-stops of human vision dynamic range. They're more like 8.5 f-stops. I believe 90 dB noise floor (linear scale) is good enough. The DSP noise in the Crown XTi-1000 was really objectionable when quiescent, but that noise perception disappeared when anything was playing. If it is only the noise floor that increases when the dynamic range rarely exceeds 90 dB, then I'm comfortable with that, and I believe that I can work around it in gain programming. However, if someone wants to hand me a Yamaha digital crossover at a fall-off-the-truck price, I'd probably consider it seriously. I find that it's the other distortion types/sources that are objectionable - such as that in passive crossover networks undergoing Ohmic heating, cooking inside of closed or nearly-closed boxes, and other forms of electro-magnetic distortion. In fact, I'd probably start to examine/invest in solutions for magnetic distortion dynamics of acoustic drivers, time misalignment of drivers in all my loudspeakers, and diffraction of dual-mouth corner horns before I'd get excited about dealing with 90 dB electronics noise floor. For me, it's all about system-level trades. My $0.02. Chris [:#]

So--you're saying, don't use the Dx38 at high input gain and you won't hear "noise floor huffing". Do you remember the relative input setting of the Dx38 at that time. I don't remember the exact Adcom preamp model number during that time. You can hear noise floor changes at only the signal peaks? Interesting.Chris

Mike,Did you hear any differences when we heard the Yamaha unit last year vs. the Dx38? I remember the difference between the JM Peach and the other preamp we heard. Interesting.Chris

I don't see any reason to stay with one amp type, other than it is more compact in the amp rack to use stereo amps to bi-amp your two-way speakers-one stereo amp per speaker (...see how I slipped that one in? [6]...)In fact, it is the reason why you might want to invest in excellent-but-low-power amps for your hf while using something more forgiving (economically) for your low-efficiency woofers. Roger that. Note that it's been my experience that high quality pre-amps are usually cheaper to build than high quality (read: class "A" SS or tube) power amps. I find that a lot of folks here ignore the effects of passive crossover component issues [Ohmic heating on device properties, heating of components inside the box, part stability over time (particularly, but not limited to caps), parasitic losses on the power amp(s), and weird net impedance loads that some power amps have trouble driving]. All that is simplified when using active multi-amping--you use one amp channel per driver with nothing in between. Chris

This may surprise you but every question that I proposed is on the level - nothing emotive or rhetorical was intended (as is usual for my posts, since irony and other forms of rhetoric are much too easily misunderstood and can lead to flame wars). I would still welcome real answers to any of my questions. The questions are on the level. I only hope any proposed answers might be also. I was so severely disappointed with my 300Bs that I could not believe that anyone would buy them. The interesting thing was that I found no negative posts on these units before investing in them. Only one argument that could make any sense as to a cause: output impedance of the Dx38 is too low to couple properly to the 300Bs, but I've got some real issues with that if true. Chris

Circuit theory, anyone? Thévenin? [8-|]

Are you referring to "bi-amplification"? Like the guard at the gate said--"...well...that's a horse of a different color..." []

See the following...controversial for some--but worth the read if you seriously want to save your shekels for the things that will make a real difference in the sound that you're listening to...[]

Is there a pecking order? [8-)]

Klipsch Academy Klipsch Heresy IFREQUENCY RESPONSE 65Hz-20kHz(+-)3dB 50Hz-17kHz(+-)5dB POWER HANDLING 100 watts maximum continuous 105 watts maximum continuous (500 watts peak) SENSITIVITY 96dB @ 1watt/1meter 96dB @ 1watt/1meter NOMINAL IMPEDANCE 8 ohms 8 ohms HIGH FREQ CROSSOVER 2,200 Hz TWEETER K-76-KV 1" (2.54cm) Polymer dome compression driver K-77-M 1" (2.54cm) Phenolic diaphragm compression driver HIGH FREQUENCY HORN 90(o)x40(o) Exponential Horn 90(o)x40(o) Exponential Horn MIDRANGE K-55-V 2" (5.08cm) Phenolic diaphragm compression driver MID FREQUENCY HORN 80(o)x30(o) Exponential Horn WOOFER Two K-1011-KV 8" (20.32cm) Poly cone K-22 12" (30.48cm) Fiber-composite cone ENCLOSURE MATERIAL Medium density fiberboard construction (MDF) Birch Plywood or Veneered Lumbercore ENCLOSURE TYPE Sealed Sealed DIMENSIONS23.25" (59.06cm) x 11" (27.94cm) x 10" (25.4cm) 21.4" (54.36cm) x 15.5" (39.37cm) x 13.2" (33.53cm) WEIGHT23 lbs. (14.95kg) 55 lbs. (24.97kg) FINISHES Walnut Oil, Oak Oil, Oak Clear, Finished Black Walnut, Rosewood, Teak Oil, Walnut, Oak, Cherry Lacquer, Raw, Black Birch BUILT FROM 19921957BUILT UNTIL 19941985

I am bi-amping Crown D-75As (same topology as mdeneen's D-45 amp), using a Dx38 to time-align, and TADs on the top end of my two-way mains. I used Bottlehead Paramount 300Bs (they're now sitting in my equipment room gathering dust) - these were the worst-sounding amps that I have ever used. These two monoblocks were built by the Bottlehead folks. After about a month, one 300B tube bit the dust on its own. Saved me the excuse to excise them both from my system. Why do these SET amps sound so poor? Chris

I believe that I was referring to Mike's "crest factor" discussion, not average SPL. Yes...it does...considerably.Chris