MARK LEVINSON HQD

12.000,00


Free Shipping!!!
Availability: yes
Shipping on: 25 Sep 2019
Product code USD0111
Category LOUDSPEAKERS
Brand MARK LEVINSON
Availability yes

Tip a friend

More questions ?

Conceived as a personal reference by Mark Levinson, a minimum production was then decided on the request. In the early 1980s it cost the stratospheric sum of $ 26,000 and was sold and installed all over the planet directly by Mark and his staff
Several artists and composers opted for this system (as the famous construction hanging on the ceiling expressly wanted by Faye Dunaway) that if well installed and calibrated is one of the most faithful and performing loudspeakers ever conceived.
There are countless "stacked" creations using the ESL57 Quad but this is the original
HQD stands for Hartley Quad Decca the whole in fact used a double pair of Quad ESL57, a pair of Decca ribbon tweeters and two 24 "Hartley woofer (not included in this proposal)
For the real thing I did several experiments with the gigantic Hartleys, moreover still available, but they didn't fully satisfy me, the best results I obtained at the moment with the pair of janis we have available, which maintain a greater homogeneity with the panels.
I personally did 3000 km to recover it in northern Europe and I do not regret even one of the km made.
A set of this kind before being put up for sale deserves an obsessive care of restoration-tuning both electrical and aesthetic. They are not simply four 57 and two Decca tweeters but they are 12 electrostatic panels that must work in a homogeneous way and perfectly identical to each other, compatibly with the frequencies they will reproduce.
Anyone familiar with the Quad 57 knows that it is rare to find two identical copies playing the same way for various reasons: factory couplings were left to chance (initially it started as a monophonic speaker, so the need to make the homogeneous pair was non-existent) is almost impossible to find pairs with neighboring serial numbers. The cells had an extremely artisanal construction, with wooden frames that, when assembled on the diffuser, were bowed a few degrees and then fixed in position. The external mylar was roughly stretched and after a few weeks of production the back of this (less tense than the front) tended to release and vibrate. Now imagine a situation that is not yet optimal after more than 50 years of use and change of hands.
There are pairs of 57 proposals on the used market for less than 1000 euros. For decades of experience, I can say that we are actually buying frames, protection grids and, if we are lucky, power transformers and audio transformers. The six cells in 99% of the cases must be completely restored.
There are four or five companies in the world that are able to do this, but in almost all cases they will offer you the new panels of their own production in exchange for the old faults. The reason is simple: none of these companies has succeeded in recreating the magic that historians can give you back when you use the new cells.
I made this long introduction to introduce the complete and expensive restoration work performed on the system in question.

 


CELLS: the most delicate part and at the same time the main responsible for the extraordinary sound quality of the system. Completely disassembling a 57 is a grueling job.
It was a project far from facilitating any future maintenance.
I will not list here the quantity of screws, staples, welds to be removed and put back there is ample documentation online, but the work is long and requires extreme care especially in the reassembly phase.
Once the 12 panels were separated from the rest, they were sent to the one I consider the most serious company and prepared for the purpose. Despite only three panels needing to rebuild the membrane, it was preferred to rebuild all the panels while maintaining the total originality of the stators, replacing the membrane and all the dust-proof mylar to obtain an absolute homogeneity of both efficiency and frequency response of the eight panels of the medium-low and of the four of the mid-high.

 


Once the panels had returned, these were put in place, after complete testing of the two transformers and replacement of the wiring with a new OFC copper conductor with insulation for high voltages.
A very important part concerns the tensioning of mylar dust cover surfaces, an operation that must absolutely be performed once the panels have been fixed to the frame and must be repeated several times after several days to be sure of absolute stability. The tensioning of the membranes is not complicated but it requires considerable experience and "cold blood" as it takes just a moment more to pierce the mylar irreparably and have to reconstruct everything.
The operation is carried out with a hot air gun which must be more powerful than a normal hair dryer but less than the classic equipment which is used for paint stripping or heat shrink wrapping. I solved it with an adjustable temperature heat gun. After many tests on cells to be reconstructed, I found the combination of the right temperature, the working distance and the most correct movement to achieve the purpose. the result can be seen from the images: "skins" stretched like drums and no imperfections.

Once the cells were put on the frame, the new cabling was reconditioned and the front and rear protective grids were re-installed, the ESL57 and the Decca ribbon tweeters were inserted again in the original Mark Levinson frames.

The frames in solid American oak are in excellent condition and required only an oiling to refresh the grain, the structure is very solid and allows the adjustment of the "tilt" that is the rotation of the entire pair of Quads on its axis so as to balance it perfectly with the listening position.

The assembled set is really colossal so it is necessary to have adequate spaces.

A peculiarity that afflicts the 57 is the delicacy of the front grids, they are in fact large and made of thin aluminum, terribly exposed and subject to dents. If these are large, it is necessary to remove the grid and work from the inside, if they are small scratches or incisions there is nothing to do.

The fact of being imprisoned two by two in the structure has perhaps helped to preserve them better the fact is that all four are just out of the original packaging, never happened to me with a 57 with the grid in these aesthetic conditions!

 

Listening:

I run the risk of starting biased because this system has been my impossible dream for decades, but the absolute sound performance is undeniable.

Imagine the marvelous clearness of the mid-range of the 57 assisted by a very high transparent extreme and, if desired, then we will see why I wrote "wanting", an extension in the low range with readiness and "almost" the same speed as the rest.

Now let's see the low range speech

As anticipated the best results were obtained with the two Janis, but a quick test gave excellent results with a B2-50 Audio Pro.

The particular type of operation of this excellent sub woofer makes it suitable for the purpose, the woofers are small in diameter and therefore have little mass to move and high speed, this is important to keep up with the lightning-fast attack-release times of the electrostatic panels and the belt Decca.

Unfortunately I was able to perform the test with a single sub while in my opinion the couple is absolutely necessary.

But if your listening preferences concern voices, both classical and jazz acoustic music with few instruments and the listening levels are not exuberant you might even think about doing without the sub and enjoying the amazing coherence of these electrostatics

Amplification:

the basic system (Quad and Decca) can be driven by a single amplifier unless you decide to actively cut the Decca, in this case a small valve with few watts is more than sufficient given the exuberant efficiency of the tweeter . In the event of a passive cut, the tw will be attenuated as it is more efficient than the double pair of 57.

It is known that the 57 have a very high impedance and almost always higher than 8 ohms but it drops sharply to the high up to 2.6 ohm above 16 kHz

it is true that it has these frequencies, the energy required is minimal but it is advisable to take this into account in the choice of the amplification that must be: not very powerful (the maximum voltage applicable before drilling the panel is 33 volts in this case, but split over two speakers per channel) stable because the argument of impedance is almost all of capacitive nature, able to work on low impedances given by the parallel of the pair on each channel. In practice, Mark Levinson had made the ML2 for this purpose.

In conclusion

I think I have a good experience in planar speakers. As I said several times in this shop the mid-range of the 57 I think is unattainable, the Stax are approaching and have a more extended image, the Quad 63 goes down lower and you are just less tied to the precise listening point, yes le Acoustat have powerful on the bass but ...., the Beveridge is a record-breaking stage .... but nothing to do, none of them reproduces the middle range with the absence of coloration, distortion and the naturalness of 57

Perhaps this system is the real squaring of the circle for electrostatic lovers.

many pictures will be add on the photo gallery soon

Registered users can share their experience with this product. Register to access all of the benefits reserved to registered users or click on login if you are already registered.