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Does the 13 000$ big ones get you the speakers, and that giant violin?
Analog Sources: Linn Sondek LP12 turntable with Lingo power supply, Linn Ekos tonearm, Linn Arkiv B cartridge.
Digital Sources: Ayre Acoustics C-5xeMP universal player; Apple 2.7GHz i7 Mac mini running OS10.7, iTunes 10, Pure Music 1.89, Audirvana Plus 1.5.10; NAD M50 media player with NAD M52 and NetGear RAID arrays; Logitech Transporter media server; NAD M51, Auralic Vega, Musical Fidelity V90-DAC D/A converters; Arcam rBlink Bluetooth DAC; dCS Vivaldi SACD/CD playerD/A system; Ayre Acoustics QA-9 USB A/D converter.
Preamplification: Channel D Seta L phono preamplifier; Pass Labs XP-30 line preamplifier.
Power Amplifiers: MBL Corona C15 & Reference 9007, Pass Labs XA60.5 (all monoblocks).
Loudspeakers: Vivid Giya G3, Rogers BBC LS3/5A, EnigmAcoustics Sopranino supertweeter.
Cables: Digital: Kubala-Sosna Elation! AES/EBU, AudioQuest Coffee, Belkin Gold USB, Transparent USB (with dCS Vivaldi). FireWire: AudioQuest FireWire 400 (prototype). Interconnect (balanced): Kubala-Sosna Elation!, Transparent, AudioQuest Wild Blue. Speaker: Kubala-Sosna Elation! AC: Kubala-Sosna Elation!, manufacturers' own.
Accessories: Target TT-5 equipment racks; Ayre Acoustics Myrtle Blocks; ASC Tube Traps, RPG Abffusor panels; Shunyata Research Dark Field cable elevators; Audio Power Industries 116 Mk.II & PE-1, APC S-15 AC line conditioners (computers, hard drive). AC power comes from two dedicated 20A circuits, each just 6' from breaker box.John Atkinson
Does the 13 000$ big ones get you the speakers, and that giant violin?
JA wrote, "...in fig.3, the upper woofer crosses over to the tweeter at a slightly lower frequency than the specified 2kHz, with a steep rolloff broken by resonant modes at 6.2 and 9kHz. These are well suppressed by the crossover..."
What I think we are seeing at 6.2kHz in your measurement is not a modal breakup resonance of the diaphram, but rather is the low pass crossover response above the notch at ~3.8kHz. The peak you measured at ~9kHz is more characteristic of the modal breakup resonance of Seas' Excel W15 family of woofer diaphrams.
The low pass crossover displays characteristic effects of an elliptical filter that combines a notch and low pass, with the notch steepening the intial rolloff of the low pass. For a description of this take a look at Albert Neville Thiele's US patent 6854005.
http://www.google.com/patents/US6854005
The magnesium woofer without a filter has resonances as JA correctly noted at 6.2 and 9kHz, but the woofer's highest peak is actually at 4.9kHz! (about 5dB above the 6.2kHz resonance). JA's measurements confirm that the resonances are well-supressed.
I have not heard this particular JA speaker. I have heard the JA Pulsar at an audio exhibition. JA speakers are out of my price range, but it was a privilege to hear the Pulsar.
The diminutive Pulsar projects an enormous soundstage that simply belies its size, and exceeds that of some larger, dare I say floorstanding, speakers. The build quality of these speakers is something that you have to see in person to appreciate fully, though they look great in this article, too.
The top-end Seas drivers used in these speakers are heartily capable, and maintain their composure, even at the highest volumes. They ably handle powerful amplification (I heard them with Hegel integrated amplification).
JA Speakers are fine products. I hope those interested get a chance to hear these speakers.