StephenM

I'd guess the Icon & Synergy lines aren't as popular around these parts simply because its mostly the hardcore Klipschites that tend to stick around these forums for an extended period of time, and before long they've moved on to RF-7s, the Heritage line, Jubs, and so on. FWIW though, if you own Klipsch speakers, you're OK in my book!!!

A bit of light reading on that topic: http://billfitzmaurice.info/forum/viewtopic.php?t=1886

SVS typically maintains there won't be much audible difference between the cubes and their corresponding uprights. However, I think I've read that the cube has slightly more internal volume, and slightly deeper tuning.

Indeed. Here's a chart of some outputs including the JL F113 and the older PB13U with the Bash amp. http://www.hometheatershack.com/forums/subwoofer-tests-archived/5748-cea-2010-standard-compilation.html

Yes; that is the THX guideline in any case. It's not out of the realm of possibility. Just depends on on how the Denon wants to process it.

What is the crossover on the Sunfire set to? That could cause such a problem. If it sounds good to you, that's all that matters. Just be mindful of the volume so that you don't damage your KLF-20s with a high power, very low frequency transient. Could be a few issues, although phase immediately comes to mind; it isn't uncommon to have a difficult time integrating a subwoofer with floorstanding speakers set to large. If you tried to send LFE to both the SVS and your KLFs, that could produce too much bass as well. When your mains/center are set to large, they will receive a full range signal and the bass content of those channels will not be rerouted to your sub.

PB13U, 15Hz Tune http://www.audioholics.com/reviews/speakers/subwoofers/svs-pb13/PB13ULTRA15HZCEA2010CHARTPASS.png/image_view_fullscreen DD18+ http://www.audioholics.com/reviews/speakers/subwoofers/digital-drive-plus-18/LDD18SERVOGAIN8CEA2010CHART.PNG/image_view_fullscreen DD15+ http://www.audioholics.com/reviews/speakers/subwoofers/velodyne-dd15/velodyne-dd-15-measurements-analysis At 20Hz, the PB13U dominates even the DD18+, with 109.2dB and 11.26% distortion versus 103.6dB and 26.78% distortion. The DD15+ is pushing 97dB with an unspecified amount of distortion. With a 12dB advantage at this point, it would take a quad stack of DD15+'s to meet the output of a single PB13U. From 32Hz to 80Hz, the PB13U averages 115.5dB output and 7.1% distortion; the DD18+ isn't far behind with 114.6dB and 8.3% distortion. The DD15 averages about 109dB, again with unspecified distortion.

I don't know that you'd want to base the decision entirely on the scorecards as I'm unsure how consistent they are between reviews; however, in no uncertain terms, the PB13U is a significantly more powerful sub than the DD15+.

In terms of raw output capability vs distortion, you'd need to look towards the bigger and even costlier 18+ for something approaching a fair fight against the PB13U; this comparison simply highlights the advantage a large vented sub has over a smaller sealed model. About the only thing the Velo 15+ offers over the SVS is on the electronics side.

I always like the story of the SMS Emden. http://en.wikipedia.org/wiki/SMS_Emden_(1908) An impressive record both of fighting/raiding and chivalry. In WWII, the German pocket-battleship Admiral Graf Spee was commanded by a similar gentleman. http://en.wikipedia.org/wiki/German_cruiser_Admiral_Graf_Spee

The RF-7 II is definitely US made. AFAIK the rule of thumb on the Reference line is that if it was wood veneered, it was US made. The THX Ultra 2 line is also US made, as is the Pro Cinema line, the Heritage line, and the flagship floorstander of the Palladium line.

For me, made in the USA (and other "first world" countries such as Germany, Japan, England, Italy, etc) invokes a sense of pride in workmanship, fair labor practices, and equitable trade practices. Made in China invokes just the opposite with their human rights record, labor practices, currency manipulation, trade practices (including a blatant disregard of intellectual property rights), etc.

Just how the relationships work out between power, voltage, impedance, and current. Power = Voltage * Current. Voltage=Current * Impedance. Power = Impedance*(Current^2). So if you've got 2 watts at 4 ohms, you're looking at 2=4*(X^2) or 0.5=X^2, or roughly 0.7 for current. If you've got 2 watts at 8 ohms, you're looking at 2=8*(X^2) or 0.25=X^2 or 0.5 for current. Yes, although one would expect that your amplifiers do have additional headroom for momentary peaks (NAD especially being particularly well known for this), so even 115dB may well be attainable if that is your goal (presuming the speakers are physically capable of those output levels). Even my mid-line receiver can technically swing a peak of 12.5 amperes (part of the THX Select 2 spec) into a 4 ohm load, equating to 625 watts. If I didn't want to be conservative with my figures, and just ran with a 99dB w/ 2.83V input @ 1m sensitivity for my RF-5s, I could say that adjusting for 4 ohms down to 96dB w/ 1 watt, I could theoretically reach 116.2dB at the listening position. Of course, I'd expect my RF-5s do not have that kind of output capability either, but it's not something I plan to worry about. 6dB is definitely a theoretical figure for a full space environment (anechoic), and real world should see less of a decline. However, I'd expect the actual magnitude of the decline would be fairly dependent upon the room.

Hi Gary, Power will of course depend on the speakers (sensitivity, impedance), distance, and of course volume requirements. Starting with the speaker, you'll find that the rated voltage sensitivity is typically rated as XdB w/ 2.83 volts at 1 meter. Enter impedance. At 8 ohms, 2.83 volts equates to 1 watt and 0.3534 amperes; at 4 ohms, 2.83 volts equates to 2 watts and 0.7067 amperes; at 2 ohms, 2.83 volts equates to 4 watts and 1.413 amperes. So while a speaker could be rated at 98dB w/ 2.83 volts @ 1 meter, it could be demanding as little as half a watt (16 ohms) to more than 4 watts (2 ohms) depending on impedance. If you were to rate by 1 watt, the 8 ohm speaker would be 98dB sensitive with 1 watt, whereas the 2 ohm speaker would be 92dB sensitive with 1 watt. Staying with a speaker for the moment, you'll notice that the current demand doubles when the impedance halves. This is not the case if you simply double power into the same impedance: 2 watts into 8 ohms calls for 0.5 amperes; 2 watts into 4 ohms as noted above calls for 0.7 amperes. Hopefully this helps to explain why lower impedance loads are so demanding. Moving on to distance, going from 1 to 2 meters reduces output by 6dB; going from 2 meters to 4 meters subtracts another 6dB. This corresponds to 4x the power for each doubling of distance. Even moving from 9 feet to 12 feet is a difference of 2.5dB, which is nearly doubles your power requirements. Finally there is the matter of volume/listener preference. Me, I don't have a use for 115dB peaks. I don't even really have a use for 105dB peaks. When watching movies, my volume doesn't exceed -20dB from reference, which equates to peak levels of 85dB from the satellite channels. I don't listen to music any louder either as verified with an SPL meter. So for me, the numbers in question are: 99dB sensitivity (96dB to be conservative), 8 foot distance, impedance of 4 ohms (per Klipsch support), and 95dB of volume (just to give myself some margin for error/headroom). Under those conditions, worst case, I need ~9.4 watts per channel from my mains into a 4 ohm load. For my rears the numbers are: 90dB sensitive (87dB to be conservative), 6 foot distance, and an impedance again of 4 ohms (conservative guess). Again, worst case, this calls for 42 watts per channel from the rears into 4 ohms. So all 4 channels driven, and assuming a worst case of 4 ohms, I need ~103 watts total, comfortably within the limits of my receiver.

To the best of my knowledge, Klipsch tests sensitivity in their anechoic chamber and adds 4dB for room gain. From the third party measurements I've seen of some of their speakers, including several in the RF line, they seem to be reasonably accurate. Heh if you think they're not efficient, I'd hate to hear what you think of the bookshelves I've got in my bedroom. Per Audyssey and my SPL meter, they need about a 15dB boost relative to my RF-5s. That's inefficient.

Unfortunately, it's just not really possible to have a sub that is significantly smaller while retaining the powerful low end output and not seeing the cost jump accordingly. A large vented box is a very efficient animal as you approach its tuning point. To overcome that, you need lots of power and a very robust driver.In terms of raw SPL, to give you some idea, it would take something like a JL Fathom F113 ($3700) to match the output of the older PB12-NSD at 16-25Hz.

The woofers are likely to be as sensitive, but not necessarily as efficient as the horn tweeter. IOW, with 2.83 volts, they probably do approach the rated sensitivity, but they are also likely drawing much more than 1 watt to do so. How much more of course depends on the impedance curve.

FWIW, you just can't expect a small sealed subwoofer to keep up with a much larger vented subwoofer for deep bass. Even SVS's own SB13+ is handily outperformed in total output capability by the less costly PB12-NSD when you're talking deep bass (20Hz-32Hz). As far as the HRS10, I don't have much data, but what I do know is that for output capability, even the much costlier Sunfire True EQ 10 is outgunned by your PB12 in terms of output capability. SVS PB12-NSD http://www.avtalk.co.uk/showthread.php?s=a4612bfc6ac3c0dd9f6d8cc583168598&t=20780 Sunfire True Sub EQ 10" http://www.avtalk.co.uk/showthread.php?t=18483

http://en.wikipedia.org/wiki/White_van_speaker_scam See:Brands Associated With The Scam

Hey dtel, I've got a china cabinet in my basement listening room; it only holds glassware (beer, wine, margarita, shots...you know, the essentials). I don't notice much significant vibration out of it, although glasses sitting on an adjacent bar are another story. All I use there is a clear rubberish shelf liner. Can't really offer any big insights for the glass doors vibrating; I'd maybe try some neoprene pads between the shelves and the door. Won't stop the vibration, but presuming the glass vibrating causes the whole door to vibrate against the rest of the cabinet, it might reduce the volume a little. Other than that, as you mentioned, silicone could help as it would give something better than wood to vibrate against. I'm not sure that re-orienting the sub would do a whole lot of good. It's worth a try, but I'd expect something to isolate it from the floor would be a bit more effective (be it a purpose built pad or a DIY job), and maybe some blu-tak behind your wall mounted picture frames.

IIRC, if you've got a corner loaded sub, the point of maximum node excitement would be the corner diagonal to the sub. If that's where your cabinet is placed, it would be no great wonder that it's rattling.

FWIW, I got an eD isolation platform a little while back for my sub. My situation was a little different: my room is in the basement, so its a tile floor over concrete. I wanted the platform because the base of my PC12 would buzz against the floor at high volume, in spite of the neoprene pads on the bottom, and as such it was prone to move around a little. Suffice it to say, that problem is fixed. However, the sub still has enough kick to cause buzzing at higher volumes, most noticeably on my stairwell itself. Obviously while decoupling the subwoofer from a floor can help to reduce vibrations transmitted through the floor and to the walls, you'll still have the vibrations transmitted by air that can cause induce resonance.

FWIW, both the SVS PB12+ and the aforementioned Rythmik outperform the VTF-15H down low (25Hz and below). The Rythmik was the standout in the Audioholics comparison with a fair output advantage through most of the range, although the updated PB12+ will offer a bit more output down low (20Hz mark). The only thing I have against them is that there is nothing in the way of objective data on either and precious little in the way of subjective reviews. They do look menacing though.

There's always the PB12+, which is no slouch either. I assume you're talking about the ULS-15, not the VTF-15H. The ULS won't have the same kind of deep bass response as a much larger ported sub obviously; however, a pair of them combined with room gain in a smaller room may well give a pretty good account of themselves. There's also the VTF-15H to consider. No question in my mind that they do offer a compelling product. On the other hand, I've seen nothing to indicate that they're offering the bargain of the century either. I'd also offer up Rythmik as a potential candidate, specifically the FV15HP. I'd also recommend reading the Audioholics reviews of the Hsu VTF-15H, SVS PB12+ (older model, but they've got some updated numbers on there last I checked), and Rythmik FV15HP.

FWIW, EQ isn't going to make those Paradigm subs deliver the same impact of your old eD subs. That said, there are plenty of other good quality makes to consider since eD left a bad taste in your mouth.