OT: Jamo has new flagship speakers, check them out!!! (big wow)

[kenratboy]

http://www.jamo.com/Default.asp?ID=2250&M=Shop&PID=5792&ProductID=17723

Note the DUAL 15" WOOFERS - I guess they took a page from the Heritage line (Jamo is now fully owned by Klipsch)

I would LOVE to hear them - or even SEE them.

Very cool - not what I would expect from a Danish firm (these things are HUGE!)

[Jeff Matthews]

I like the yellow or red ones.

[el jopez]

wow, those look... different. I too would like to know how they sound. To me they look like a pair of Martin Logans with actual woofers on them

Joe

[Bill H.]

Here are the specs on the Jamo R 909.........

R 909

Dipolar loudspeakers have existed for many years, but most examples have been electrostatic-types. While the sonic quality of these designs is often very good the main problem with this type of speaker is bass frequency reproduction is often compromised - they aren´t able to produce the characteristic physical bass thwack´ in your midriff. To solve this problem, chief acoustic engineer Henrik Mortensen decided to use electrodynamic loudspeakers instead of electrostatic ones the results were amazing.

During the process we faced quite a few challenges, Henrik Mortensen admits. It was quite a task, to make an elegant and aesthetic design for a loudspeaker of this size. But I think we´ve succeeded with the Jamo Reference R 909 without compromising performance at all!

With the launch of the Jamo Reference R 909 we offer you the opportunity to experience music, as it should be heard - live! This revolutionary new floor-standing dipolar loudspeaker employs two massive 15in woofers, a Seas magnesium midrange driver and a customized Scan Speak Revelator tweeter, all mounted in a 43mm thick baffle made of a unique multi-ply construction... this is a speaker that is set to change the face of the high-end speaker market.

The R 909 is the perfect match for the highest quality amplifiers on the market. However, with a high sensitivity of 89dB and offering a very stable load at 4ohms it doesn´t need a power plant to drive it although it will handle more than 800 Watts of peak power if you really want to go there! The design and drivers used reproduce wonderfully transparent vocals and a response so dynamic that it´s hard to believe that you´re actually listening to a speaker. The exceptionally firm bass, blessed with immense transient speed, precision and fluidity throughout the frequency range (and absolutely no colouration or reverberation) simply puts you in the middle of the sound experience.

It may all be hard to believe it´s possible but a quick demonstration is all it takes to be convinced - sit down, take a listen to the R 909 and you´ll hear the proof.

Specifications:

system

3-way dipole

Woofer (inch/mm)

2 x 15 / 2 x 380

Midrange (inch/mm)

5½ / 150

Tweeter (inch/mm)

1 / 25

Sensitivity (dB - 2,8V / 1m)

89

Impedance (Ohm)

4

Weight (kg/lb)

63,1 / 139.1

Dimensions (HxWxD/mm/in)

1276 x 488 x 541 / 50.2 x 19.2 x 21.3

Frequency Range

25 - 30.000

Crossover Frequency

250 and 2.000

powerShortTerm

Min 800

Dipolar
Placing a cabinet speaker (pressure transducer) in a room creates its own unique challenges. So exactly how does a dipolar speaker (or velocity transducer) behave?
Due the dipolar radiation pattern, sound is distributed from the front and rear of the speaker in opposite phase. This is important because with a conventional loudspeaker, side wall (i.e. 1st order) reflections typically are in opposite phase with the direct transmitted sound from the drive units i.e. they sound annoying.

However, with a dipolar radiation pattern there is virtually no "sideways" sound transmission and so the critical 1st order sound reflections are practically eliminated.

But, you might ask, what about the sound transmitted from the rear of the speaker doesn´t that destroy imaging and the soundstage?

Actually, when placed correctly the laws of psycho acoustics come into play. The human ear uses the first sound received (the 1st wave-front) to determine the direction of the sound (i.e. where it´s coming from). That means that even if reflected sound is slightly delayed it doesn´t affect the brain´s ability to determine direction.

If a dipolar speaker is placed a minimum of 3ft/1 m away from the rear wall and angled in slightly (as a serious listener with cabinet speakers would probably do anyway), the reflected sound will be delayed (due to physical distance and the fact it will be bouncing off two boundaries before reaching the listener´s ears) but it still gives directional cues. Now the 2nd order reflections add ambience and give the listener the impression of a much larger room.

Front baffle
The 1.7in/43mm thick front baffle is made from no less than seven layers of MDF board, glued together and shaped under high pressure. The rounded shape provides optimum working conditions for the drivers as it prevents diffraction and improves rigidity even further.

The baffle itself is attached to a 60lb/26kg cast-iron base housing the cross-over network and the bi-wiring XL binding posts, they connect directly to the crossover network placed inside the base, so securing the best possible signal path. A solid double 5x60mm stainless steel brace with a special damper ensures a rock solid connection between the baffle and the base.

Midrange
In order to fulfill the R 909 brief we also had to use state-of-the-art technology for the midrange driver. Employing a patented Neodymium magnet arrangement, the Seas unit uses a magnesium cone for its stiffness and low weight, both vital qualities for dynamic response. Thanks to the HCC (Hard Conical Cone) technology the driver is able to reach all the way to 9kHz before any significant cone break-ups occur. This makes for extremely low distortion throughout the range plus a very open and detailed midrange for optimum voice reproduction. Turned from solid brass the centre-plug has a cooling effect on the voice-coil, providing greater power-handling capability and most importantly, extra sonic stability when playing at high volume levels.

Tweeter
There was only one choice when it came to choosing a tweeter to reproduce the delicate treble frequencies the legendary Revelator from Scan Speak. However, since this model features a relatively large face-plate, it would have needed to have been placed further away from the midrange than would be ideal. So, in order to obtain a seamless transition with the midrange driver, we chose to fit a smaller cast-alloy face plate.

The tweeter features a 1in textile dome which is coated several times to obtain a unique combination of dynamic linearity and resonance damping, the result being an incredibly smooth, linear, dynamic and incredibly transparent sound.

The driver´s Symmetric Drive Technology - a copper ring on the pole that extends past the voice coil, curving into the dome chamber - practically eliminates electrical phase shift. And, just as it does with the midrange, it also lowers distortion significantly.

To eliminate turbulence the double-damped, optimized chamber behind the magnet system is also equipped with an anti-resonator-plug. And the specially designed chamber under the cloth surround minimizes air noise and compression. Actually this tweeter is so carefully manufactured that damping unwanted resonances using ferro-fluid - the usual way - is rendered unnecessary!

Woofers
Most woofers are developed to work in a cabinet, and as a woofer constructed for a dipole application is very different from a traditional boxed one we had to develop a special woofer for this open-baffle application.

These huge bass drivers employ high quality magnesium baskets plus lightweight, air-dried paper cones with a rubber suspension. The time-consuming process of letting the cones air-dry instead of just pressing out the water in the former - has resulted in a thicker, and thus more rigid, material for the same low weight. Although paper cones might be out of fashion in some circles they have the ability to start/stop moving incredibly quickly, can reach very, very deep and they endow the drive unit with great sonic precision and musicality.

X-over
As should be apparent from the drive unit descriptions, we wanted to start out with drivers of immense fundamental quality, precisely so that we would only need minimal assistance from the cross-over!

Consequently, the cross-over in the Jamo R 909 is of a relatively simple in the most positive sense of the word low-order configuration. The advantages of using the 2nd order filters that are in the R 909 is that both electrical and phase angles are kept at very small values, something that´s of great importance both in terms of sound quality and the eventual load on the amplifier. The use of quality Solen foil-capacitors and air-coils in the crossover further ensures sound quality.

[Duke Spinner]

better buy a 1000 watt amp , too ......

[Daddy Dee]

The specs look very good. I'd sure like to hear some.

I'm not a prospective customer, so I won't fuss about the cosmetics. They look better (to me) than I expected and could be an acquired taste.

[rockbobmel]

Very interesting... I bet they cost a lot..... No cats allowed!

[jdm56]

Very interesting. I've been intrigued by the "dynamic" dipole concept since Audio Artistry did their thing with them a few years ago. Also, the Legacy Whisper is an impressive take on the design. They do all seem to require huge, multiple woofers to make good bass, though.

[damonrpayne]

Isn't there some form of relationship between Klipsch and Jamo?

[kenratboy]

Isn't there some form of relationship between Klipsch and Jamo?

Read my post and you will know [] - Klipsch owns Jamo.

[SteelerFan]

Very interesting... I bet they cost a lot..... No cats allowed!

I'm also curious how much they list for. I thought most Jamo's were priced moderately.?

[3dzapper]

"better buy a 1000 watt amp , too ......"

They should be around 90DB efficient duke.

Here is another view:

List is said to be 10,000 Euros (12,500USD)

Rick

[sfogg]

Be cheaper to build a pair of Linkwitz Orions... which look to be the inspiration of the Jamo's.

http://linkwitzlab.com/orion_us.htm

Shawn

[Scp53]

Those look nice.

But how does that "open back" design work? Wouldn't the woofers have little output(especially on the really low notes) because of canceling? I know that is true in free air and this design is pretty close to free air. Or does that "open back" tune the speakers in some way? hmm....

scp53

[pauln]

My instincts tell me these Jamo are junk. The big woofers are too large to be out in the open. No box? They will flap-out trying to play the low notes. Will they cancel/comb as well? 89dB? Maybe they are really a kit - when you get home you cut huge ironing-board sized holes in the wall and install them?

[boom3]

I'm thinking the woofers are of the hi-Q type (Qts of about 1.2) also called fre-air. Carver used six (I think) of them in one of his speaker projects. The high Q means the bass is actually quiote acceptable without an effective baffle, but a high pass filter is a must to keep infrasonics from destroying the woofers or causing distortion.

Anybody know the MSRP of these?

[sfogg]

"Wouldn't the woofers have little output(especially on the really low

notes) because of canceling? I know that is true in free air and this

design is pretty close to free air."

Yes, there will be signifigant EQ in the crossovers for these to boost the output down low to keep them flat with the canceling.

One of the benefits of dipole bass is because of the canceling less

total energy gets put into the room in the bass region. I think

Linkwitzs says it is around 4-5dB. That helps lower room effects in the

bass too.

Check out Linkwitz site. He has a huge amount of information on dipolar

speakers and how they interact with the room. He Orion's get raves from

just about everyone that has heard them. They need to right room to

work in though.

Shawn

[jt1stcav]

Couple of years ago my brother built a pair of open baffle dipole subs consisting of two efficient 15" Pyle Pro drivers per "H" shaped cabinet (one driver facing out, the other towards the back). He refered to the Linkwitz site for his research, and once they were powered up by my old Carver M-400t power amp and an AudioControl Richter Scale Series III bass equalizer/crossover, they actually produced a considerable amount of bass (with a bass management program and calibration mic from his laptop, frequency response was rated at least 18Hz before it dropped off the chart at a decent dB rating that I can't recall). I never would have guessed that these open baffle dipole subs could generate sizable bass that could equally be felt as well as heard (no lie)!

The only disadvantage are their size (a little taller and deeper than Cornwalls)...once he got an InFocus rear projector and a 100"+ screen tacked to the wall (the AV rack was moved to the left wall), the dipoles were just in the way. He even bought a massive SVS PD12-ISD2 sub that sounded awesome but was also too big and got in the way of the screen (the room is small and there's no room for subs placed behind or beside the couch). So now for the time being he's using his fullrange Definitive Technology BP10 towers (20Hz-22kHz)...there's bass but no punch, and DVD movies are left lacking...