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Vintage


McIntosh XRT 22: The Quartet

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McIntosh XRT22

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It's one of those days in which you don't feel like working and you crave for  something different. So I gladly agree with Domenico Pizzamiglio, friend and "Hi-Fidelity colleague" to visit a shop in Gallarate - a shop we already spoke about: Pieffe Elettronica. The reason for  visiting is that he wanted  to listen to a couple of Audio Note loudspeakers. Once we get there, Domenico familiarizes with his future new loudspeakers and I look around the different listening rooms of this big shop. I listen to a couple of big Cerwin Vega! XLS215 in one room and  in another room I bump into one of my youth myths, a couple - well actually it's four of them - of McIntosh XRT22. 

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I'd love to listen to them and I start thinking how to ask it to Marco - the shop owner -. It's sooner done than said, his shop assistant brings into the room a big old McIntosh MC2500 amp to make them play, since these "big guys" need a powerful amplifier. Just a few seconds and we immediately understand that we are in front of two aces. They are put in a room that is not really fit for listening - as you can see from the picture -  but the bass is extremely powerful and extended. As for the high range it must  be re-listened and evaluated in a different setting. A Bach’s "Toccata and Fugue", a record that Marco suggested brings out an organ pedal that literally makes us jump up from the couch.

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McIntosh XRT22
Well, what else can I do then? Exactly what you are thinking. I have to test them in my own listening room so I agree to come back in a few days with a van to take them home with me for an accurate evaluation. The idea of buying them is slowly creeping in my mind. I read about their history and characteristics on the website where the designer, Roger Russell, explains all the details and the procedures that led to their construction and production in the McIntosh plant. We will examine all the details that you can easily find in the website and we want to thank Roger Russell for letting us publish his pictures and also for letting us quote his article.

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As I said before this set is composed of 4 pieces. The large and small cabinets contain both two 12" McIntosh woofers and a 8" McIntosh midrange. The crossover, whose prototype you can see in the picture, cuts at 150 Hz the first woofer, at 250 Hz the second and at 1500 Hz the midrange. For ranges over 1500 Hz there are the twenty-three 1" tweeters made by Philips on McIntosh specific design. The columns are linked to the bass unit with a proprietary cable. The declared frequency response is 20 - 20000 Hz and the applicable power is 250 w RMS with peaks of 500 W. Sensitivity is 87 dB. XRT22 have been produced from 1986 to 1993 and in the US their price was around 9.100 USD. Supports for the columns, that are provided with a hook to hang them, are sold separately. For further information I suggest to take a look at Roger Russell's website that is full of interesting suggestions on the speakers and much more.
Well, after a few moments of listening in the shop, Domenico and I started wondering why these loudspeakers had little or no success in Italy. One reason might have been their high retail price but there are vintage "monsters" that are still the object of desire for many - and I'm thinking of JBL Paragon, of the big Tannoys or Altecs - while XRT22 are lost in oblivion. McIntosh loudspeakers, despite electronics, have never had many followers here in Italy and I am sincerely surprised after having listened to them. The only reason I can figure out is that of their difficult positioning in a room. These two loudspeakers are really big and heavy. As I already said the bottom end of the XRT22 is buoyant and is almost a "massage to your guts". For this reason they need to be positioned in a room that minimizes all the resonances. I read in an online forum that a US owner positioned them in a very big room but had to buy an equalizer to "tame" its exuberant bottom end.

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McIntosh XRT22
My room, on the other hand, is strange and debunks all theories about the ambience response. It's a small room, only 20 square meters but due to its plan, it does not have resonances in the bottom end and it absorbs a lot of energy. At first I positioned  the XRT22 in the place that I thought might enhance the bottom end in this room: the two corners on the front wall. But to my big surprise no bass, nothing at all. This is not all, the preamp volume knob was turned at "3 o'clock", while working with the two 400 W Brystons, but the sound pressure was not what I expected. I don't give up easily so I pulled forward the bass unit of about 1,5 meters and the bottom end listened in the shop shows up again. From that moment on it's been a matter of fine tuning work what I have done moving the components from the sides and the front wall. It took almost half a day of hard work but I succeeded in finding the ... right low range position. I still had to place the tweeter towers and I was a little bit worried for two main reasons: one is that it's not  easy to set up two different components and the other one is the relatively small dimension of my room. I begin with the position that Roger Russell suggests, the towers positioned on the inner side. I immediately realize that this position is not right, the image is too flat in the middle. The project probably envisaged a bigger space so I move them on the outer side and the effect is that of an immediate enlargement of the scene and of the "listening line" that almost blows away the walls ... unbelievable, but not enough yet. At what distance from the front wall should I put them considering the bass units? Russell's website does not give instruction and I don't have the owner's manual. I ponder on the fact that if the two columns can be hang on the walls and the bass units can be positioned close to the same wall,  so the correct set up must be with the column in line with the bottom of the cabinet ... but it does not work. Maybe it's because the two columns are positioned on the outer line. I try to toe them in, I move also the bass unit towards the listening point but I don't get the desired result. The sound is not in phase, there's something "detached" in it. I listen to "Amused to Death" by Roger Waters and I hear the famous dog barking in front of me and not on my side. No, it's not correct yet. After another day of movements and tests I find the best position for the tweeters at about 20 cm from the woofers and not too much in front of them in order not to cover the midrange output. The dog now barks closer to the right side, it's not perfect but we are not that keen on special effects and the global sound we obtain is really very good. Many times I have wondered if these last twenty years have passed in vane in the electroacoustics field. I will describe the sound of these McIntosh and make a comparison between them and my JBL 4350B that are well known. Let's start with the bottom end: XRT22 defeats JBL both for deepness and quantity. They have nothing to envy to the Californian loudspeakers as for sharpness, even if their sound is more mellow and less close to reality. No matter how loud you make them play, the sound of the voices and the medium range in general remains clear and clean. I have never heard something like this. The medium range cannot compete with the super performing JBL compression drivers. But this was an easy guess. I think that at the moment there is no midrange that can get close to the sharpness and speed of the 2240 drivers, loaded with the small horns. About the high range we can say that it's not as good as that of JBLs (but it's not that far from them) and the fact that it comes from high columns creates an extraordinary wide and big soundstage. Records recorded in churches or theatres touch from the very first minute of listening. The XRT22 take you instantly to the place where music comes from. It's not only the front wall that plays, it's the whole room that's playing ... well no, it's the whole room that plays so loud that it disappears. It's an incredible effect that makes you think of a multichannel system, but sound is coming from one direction and not from the back. Dynamics is good but the loudspeakers have to be pushed a lot. They need 250W if you want them to play as in a live event or close enough to it. They have a fascinating sound, more tamed than that of the "wild" JBL monitors, but I do not recognize them as an alternative. The ideal would be to have them both and use them alternatively according to the mood of the day. To keep them both one should have a room with a 5 meters wall. I do not have this much space so I am a forced to choose. It has not been easy.
The McIntosh speakers left my room one week ago and I still miss their presence. I chose to stick with my JBL because they have a peculiar sound I cannot do without. What I really miss of the XRT22 is their beautiful and impressive bass. I'm trying to compensate to this lack with a subwoofer, let's see if I will find a solution. For a moment I have considered the possibility of keeping both loudspeaker and use them alternatively. I have given up because moving them in and out of the room would be very hard and, while not in use,  one of the two would have had to stay in the dust and get damaged. I let the XRT22 go with a sad heart, but I feel good thinking that they will be welcomed in the room of a music lover that will make them play every day.
Well, the reason to tell you this story is to remind to fifty-year old persons and let young people know about a loudspeaker that is not as famous as it deserves. And if someone tells you that McIntosh did not produce good loudspeakers, well tell them they are right. These loudspeakers are simply wonderful. A big thanks to Marco Pavan of Pieffe Elettronica that made this experience possible.

Angelo Jasparro



Domenico's comment

There are experiences and sensations that are unforgettable.
It's 1979, almost the end of the year. I visit a shop in Torino that is located in Cernaia street, to collect my brand new Magneplanar, and I see two big and long items that stare at me from the bottom of the room. Their logo identifies them as music reproduction items. I remember being a bit impressed by that long line of tweeters. The MG that I was taking home are not small but those other loudspeakers were really big. During that day they were promoting Threshold, American amps that had very good reviews. That name was at the time an emergent brand but now it's part of the recent history of audio. 
I remember that I was with a fellow soldier that became a friend of mine, and we were listening to a piano concert. Suddenly my friend Alberto said: " too bad that the piano player has dandruff, look, it's there, on his shoulders ..." I stared at him with a quizzical look at first but then I understood that he was referring to the realism of reproduction. As a matter of fact those components were really impressive for the time and for the recording techniques of that time. While they were loading my Maggies, Alberto and I remained there, motionless, to listen to the music that the McIntosh XRT22 were playing. 
I have lived again this experience with Angelo Jasparro when we played Vivaldi's "Four Seasons", performed by  Drottningholm Ensemble (BIS) and I have heard Niels-Erik Sparf violin play in front of me, just few meters away; loud, with a realistic timbre, dinamically free and with the environment resonances that created a very realistic situation. A sensation that gave me goosebumps. I cast a glance to Angelo and then, off we go listening to a lot of records. Well, we must keep in mind that JBLs have a bigger ability in managing dynamics and that are preferable if listening to rock or frenzied rhythms, but the McIntosh loudspeakers have the rare ability to create a realistic soundstage and have a great timbric fidelity. It's impossible to recreate in a house the greatness of a pipe organ but the powerful bass of the XRT22 is able to deceive very well. Moreover it has a very high top range and a tall soundstage, all these characteristics together create a realistic effect that not many other systems are able to create. It manages also ample dynamics effortlessly and can recreate easily either the orchestra soundstage and the voice of the Boss Bruce Springsteen. I must say that with small ensembles, this is the most realistic experience that I have had. 
To carry them into the listening room it's been a hard work but it 's been worth it. 

“Oldies but goldies” it's a saying that turned out to be true. What I experienced is a flashback that has not erased the nice sensations felt in 1979 but has enhanced them. When something is of good quality it remains so also during the years.  


Domenico Pizzamiglio  
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Domenico
Translation: Francesca Rubino

Six questions to Wolf von Langa: Audio between past and future
by Alessando Costanzia di C.

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A cycle of exclusive interviews to famous people in the most extreme Hi-Fidelity starts here. This is the Hi-Fidelity that is stranger to the commonest commercial logics, the Hi Fidelity that has as its flag the purest research on new materials and technologies and often has as a starting point the golden age of electroacoustics and projects itself with strength into the present and also into the future of audio reproduction. Our guest today is Wolf von Langa, a renowned name for high efficiency and high performances components fans. He is one of the famous names that champion the field coils loudspeakers.




 
1) Good morning Wolf, watching your beautiful home page - www.hqspeaker.com - we find out straight away that your passion for music reproduction is an old passion. Introduce yourself to our readers and tell us
about your experience of being first a user and then a famous manufacturer.
 
 
WvL: I remember my first tin soldering, I held it when I was 8 yo. At 9 I had already finished my first working model of a steam machine. That same year I went along with my father to the transformers' plant where a family friend prepared for me all the pieces that were necessary to build a " Detektor" a sort of radio that worked without electricity. With this radio I started to search in the air sounds and harmonies that came from far away Countries and this really put a spell on me. When I was 14 yo I started to build my first speakers with Siemens and Isophon components. At 16 yo I completed my first horn system  with experimental technologies and calculation. When I was 20 yo my first job kept me busy for over a year in designing the first digital studio in Germany with a monitoring room with UREI systems, a director's room following the ideas of Andy Munroe and 4 studios with different acoustic performances. After this I had the opportunity to master my abilities designing important monitoring and directing studios. After this I followed closely the opening of shops in the field of High-end in French Swiss and in Erlangen, and my interest in this matter together with my curiosity made me explore better all the best of the world production going from the movie systems of the 40's up to the most modern and ambitious systems. This apprenticeship lasted several years during which I gathered a vast personal collection of historical professional material and of cinema material. The opportunity to mach continuously technical and music characteristics with the best historical components made me think that the technology applied to music reproduction stopped in the 60's. So I decided to make a change and from sales person I became a developer and manufacturer. A decision that I don't regret. continuously technical and music characteristics with the best historical components made me think that the technology applied to musical reproduction stopped in the 60's. So I decided to make a change and from sales person to developer and manufacturer. A decision that I don't regret. 

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2) Your research tries hard to put together music emotion and applied high  technology. How are your present products compared to the great past achievement such as Altec or Western Electric? 

WvL: in the 30's electroacoustics, that is to say the science of transforming the electric signal into an acoustic signal was just at the beginning. The first dynamic loudspeaker was developed by Siemens but there was no amplifier able to make it work. The big commercial interests that surrounded the movie industry were the financial trigger for the manufacturing houses together with the many people that were attracted by this new kind of entertainment . All this brought to electroacoustic industry a continuous flow of money that led to a period of technological research and development in the material used with a new intellectual richness. But a first hindrance is to be found in the low electric power available. There was a strong need for high efficiency power transformers. The sound had to be directed and sent into one direction, towards the public with horn or dipole systems. (The classic example is Siemens Klangfilm Bionor). The result was the realization of transducers with a high magnetic power and a light and rigid membrane that today manufacturers are no more able to build. Creative people such as James B. Lansing developed very exclusive loudspeakers and technologies and some revolutionary engineer achievements. The availability of materials was limited; among the available materials there were paper, copper, aluminum, iron that remain, in my opinion, unsurpassed also nowadays in the construction of loudspeakers. The materials I use today in my manufacturing house are still the same but employed together with brand new materials and very advanced techniques of simulation that were unthinkable in those years. The best of both worlds all in all.
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3) As an architect I cannot help noticing a technical approach that is also attentive to the aesthetic and formal aspects. Materials, shapes compositions and a formal language in your products tell us a strong tie and a worship of the golden years of electroacoustics but also a futuristic aesthetic vision inspired by the charm of these components.

WvL: I have developed in the course of the years a personal vision that unites without contradictions aesthetics aspect and technical performance. This is applicable to all the objects I produce. As for the research of music performances I've been inspired by the great achievements of the past. But now I can affirm with a certain pride that my latest loudspeakers have a music maturity that has nothing to envy to the models that inspired them. 
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4) Field coil technology: is it only nostalgia or is this the expression of technology in its highest form? There is a saying in electroacoustics that goes like this: if ferrite is water from a glass, alnico is tap water and  field coil reel is  pure spring water. Is this saying still valid? even today that there are big and powerful neodimium magnets? Tell us something about it.

WvL: The shape and type of the magnetic engine of a loudspeaker are a simple and fundamental component for the acoustic performance of the same loudspeaker. A Kevlar cone has a different sound from a carbon one or from a foamy material. The same principle applies to the reel material, the circular suspension and the spider. Let's say that the magnet is like the fuel in a car - hard to think that its performance on the road doesn't depend on the propulsion. A diesel engine expresses itself differently from one that uses gasoline. For loudspeakers the magnetic force can be generated in different ways but its speed or smoothness generates very different dynamic reactions in the in the membrane. Very important is also the choice of the material that rests close to the magnet. The audio industry employs common iron or in the best cases low oxygen iron and only the best and most expensive loudspeakers systems can afford permendur. For the industry the use of a rare earth magnet or a neodimium magnet means a big gain in weight and costs if compared to a ferrite or ALNICO magnets (that is to say Aluminum, Nickel and Cobalt just like in the most famous historical loudspeakers). The best solution is the electromagnet but this has very high costs that modern audio industry can rarely afford. The electric power necessary for it to function makes the loudspeaker dependent on a electric power source and the high content in pure iron makes it very expensive, very heavy and big. But for the lovers and for those that want the best I see no alternative and I dedicate to them my production to which I am completely devoted.
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5) Another important chapter is the technology of the cabinet. In your production is evident your preference for the open baffle. But how is it possible that in our hyper technologic era the design of a cabinet free from bad echoes is still a chimera? As audiophiles we are literally bombarded with advertisements of manufacturers that boast their personal secret recipe for a solid cabinet, solid as an aircraft bunker. I want to know if you are like the other manufacturers, like Norbert Guette or the designers of the French school that use natural materials such as wood with different thickness that vibrate as a music instrument.
I personally think that the music quality of a material is not only a physical matter, or technical matter, but also a more subtle and undefined matter. 

WvL: once Paul Klipsch defined his horn loudspeaker a Stradivari violin. No lutist in the world would ever fill the inside of his instrument with straw to deafen its sonority. Despite all this his transducer had a very high performance. The man has a inner desire to listen to music in the best and most natural way. There are million ways of measuring but the human ear and brain are a mistery to us. When our friends or relatives go to a concert we technicians cannot foresee the effect that the performance will have on them on their minds and on their souls. So we measure all that we can measure, the answer in frequency and width, the phase, the static distortions and the distortions provoqued by the cabinet. BBC and Martin Colloms published a chart that measured the residual energy conveyed by a panel of the same dimension but made with different materials: the most different type of woods and also metals, lead and aluminum. If we analyze the cabinets and the material they are made of, we can find light cabinets - just like fruit crates - or those made with the most exotic and strange materials, from stones to composite materials with resin or aluminum. Most of the times though the material used is very cheap, like the always present MDF; If we want to listen to the loudspeaker itself, going over the diatribe muffled cabinet or sounding board - we have to reconsider the old dipole. No matter what it seems an open baffle is a complex and bulky system and it's also expensive. And then we need the mass, not a mass to record and dim the vibrational energy, but a real static mass, a silent counterpoint to the vibrational energy emitted by the loudspeaker. The baffle in my system A100i, is designed as a sound screen and together with electro excited transducers Kilimanjaro it simply fills music with life.
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6) The greatest part of your products is made for evolved audio-builders that  are technically prepared and are very demanding as for performances. Tell us about your offer both for ready products and building kit items.

WvL: The electro excited components production is very demanding, limited and expensive. It cannot be available for a wide public. Furthermore there is the cost of the continuous research effort that is a cost that rests only on  the manufacturer. The commercial space is very limited. For the classic hi fi shops this product is not profitable so they are not interested in it regardless to its qualitative level. I am really proud of the quality of my products and right now I'm trying to distribute it myself. As for the foreign market I can foresee a profitable cooperation with cherry picked distributors. My output has right now 15 models of field coil loudspeakers, 2 building kits and the 2 ways open baffle system named A100i "Black & White" ( recently shown in Munich with a great public success).
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Thank you for this interview.  

Alessandro Costanzia di C. 

Exclusive interview with Wolf von Langa
(All the images are copyright © Wolf von Langa )

German language version of this interview is available in the italian page

English Translation: Francesca Rubino

Altec Duplex 604 - the return of the Giants

It's a strange world, our perfect world ... with its technological adrift.
iPod, iPad, Minitablet, Earplugs and Minibox are a nightmare for an entire generation, my generation, lost in the memory of shining audio amplifier front panels, dancing pointers of vu-meters and 15" woofers that had the power to remove dust from all the small knick-knacks our parents displayed on the living-room furniture. 
The cold, hyper-designed white appliance, dematerialized, miniaturized - with a sensorial pressurization similar to that of an airplane cockpit - is king and accepts everything provided that the emotional impact remains limited. The small world of the home Hi-Fi makes no exception. The loudspeakers become smaller and smaller, stylish, wife or mother in law apt and endangered by the risk of looking too feminine or domestic. Oscar Wilde would ask what's left to us, poor men, to have fun with, that's not evidently illegal?

Fortunately there is an antidote! Available In the Hi-fi sector and not too expensive. I'm talking about the mythic concentric Altec 604 Duplex transducer, born in the 40's in Hollywood, Ca. and still in production. Its last version is the 604-8H-III and it is, together with the Tannoy Super Gold, the most famous audio transducer in history. It's a real American icon, the Harley Davidson of the loudspeakers. It was born more than 70 years ago but is still alive and kicking and adored by connoisseur all over the world.  
It's a product that belongs to Jurassic but still à la page. It has the capacity to amaze with its features the smartest listener. It is accustomed to cutting edge materials like beryllium, titanium, ceramic and artificial diamond. Materials ensuing aerospace industry that now belong to our listening rooms too. 
Its look tells us about a lost world. It has a wonderful polished body with a charcoal black, emerald green or grey/white colour that scares a bit. It weights 18 kilos and has modeled forms. The forged steel basket, the 15" paper cone, the heavy Alnico made magnets, the concentric pressure tweeter with bakelite horn in the central cone are all features that tell us about a world that is poles-apart from our world that refuses the manly show-off of technology and hides it with fake coyness in a shiny body. We won't linger on describing the differencies in the production of the first "A" down to the "K" series, these are all pieces of information that can be easily found on line. I just want to point out the fact that while the first Hollywood production with the blue mark is very high-priced, the most loved - for their sound- are in ascending order "C", the rare "D" and "E".  
(fig. 1, 604D and 604E compared)

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fig. 1

Please note that these transducers, born as monitors for the most important recording and broadcast studios, were sold without cabinet whose measures and forms were only suggested. Among the others the best known for its sound quality is the "620". More than 300 liters proudly shown and with the features dangerously resembling to those of an industrial washing machine. 
(see fig. 2, assembled cabinet 620)
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fig. 2

What should we expect from these giants once built its cabinet? First of all a very low rate of feminine approval, near the zero point, with the counterpart of a very high sound enjoyment, full, long and slow, quoting the words of a famous Italian song. The decision is up to you. These object have a dimension that requires a collocation in a secure no-fly-zone, far from the sight of wives or fiancées that might spot in you hidden maniacal tendencies.
Well, it's about time to let you know how these "big boys" sound. Two simple words: wonderfully well. 
It's important to say now that I have my personal scale of values. I am a passionate of musical reproduction and I prefer to avoid the classical Hi-Fi reviewer music and the audiophile nostalgia tout-court.
I don't like the actual stream that tries to imitate the old slow sounds of past days. To define this trend I have coined this expression: "performing vintage", that is to say a line that divides yesterday's objects into two categories: the oozy and the aces. This last category includes: Garrard 301, Thorens 124, Emt, Quad Esl 57, Marantz Model 9 just to mention few well known equipments. 
From a pair of 604, correctly used, you can obtain an emotional and provocative voice, that can be highly defined, transparent, vivacious, dynamic. A perfectly sculpted image that only concentric or wideband speaker can do. Coherence is incredible if we consider the high crossover frequency for a 15" at around 1500 Hz and a bass not too deep but fast and timbric with a wonderful performance of woods, double-bass and piano of course. The 604 is one of the preferred monitors of big names such as Doug Sax of Mastering Labs especially for its performance with keyboards. Listening to classical jazz authors such as Armstrong or Bill Evans, Ella Fitzgerald or Elizabeth Schwarzkopf and the famous tenor Hermann Prey is a unique experience, fascinating like no others. Like all good loudspeakers it prefers a close and angled listening and loves LP's, CD's or high quality master tapes. If you use modern multi microphone compressed recordings the result is very poor; garbage in- garbage out the old rule is still in force. 

Here is a list of precautions that must be strictly followed. The 604, despite its age, it's a pureblood and thus must be treated to avoid disappointment and respective curses sent to the undersigned.

A) As a general precaution avoid buying equipments that come from recording studios that don't have a perfect condition and appearance. 

B) Check the integrity of the tweeter membrane. Original materials are far better than the spare parts. 

C) The measurement of the resistance of the two voice coils is fundamental, the closer the values the better they work in couple. Matched pair with consecutive serial numbers are ideal. 

D) Avoid special offers and budget an expense of 1500,00/2000,00 USD for each pair of C and D series (all at 16 Ohm) plus shipping and custom duties.

E) Original crossovers are not up to the product and other 500,00/1000,00 USD must be budgeted to buy better crossovers. Iconic Audio offers a high quality serie.
 
F) the project of the 620 cabinet is highly performing and has a good sound rendering. The best materials are the multilayer birch wood and the correct thickness is 3/4 inch. Cabinets too muffled, MDF or cheap chip-board must be avoided to keep the sound harmonic. 

G) Interface: efficiency exceeds 100d and the accepted power – 30W – impose triode single-ended tube amplifiers of good quality, using 300B or 845 vacuum tubes. I use Vaic Valve triodes with VV52 tubes, a tube with explosive dynamics and very “opened” on high frequencies, with a result really convincing. As for the cables, I recommend thin silver-good quality cables, such as Kondo SpZ or similar.
 
My exploration in the fantastic and still up to date world of these transducer ends here. There is still a lot to say on fine-tuning for example or on the recent thematic achievements of some big-names such as Jean Hiraga, Jeff Markwart, Jean-Marie Piel and Wolf Von Langa. The latter proposes a change into field-coil  that is to say with electro-wired coil, the Graal of audio mythology.
For those that want to delve into the subject there is a lot on line in dedicated web pages that we signal here:
www.audioheritage.org, www.alteclansingunofficial.nlenet.net and www.jblpro.com. 
More can be found in the writings of the many lovers and connoisseurs that live in the different countries.

Alessandro Costanzia
 
 Translation: Francesca Rubino
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