This is an article from the first issue of THE AMERICAN AUDIOMANIAC, a magazine available free of charge from TGI by faxing (604) 925 1354. It will also appear appear in Positive Feedback Magazine (503) 254-3866
EXPLORING THE JAPANESE Nth DIMENSION
OF HYPER-SPACE: PART III
IT IS BETTER TO DO IT IN THE FRONT THAN THE REAR
The Love Making Secrets of Japanese Audiomaniacs Revealed
Dr. Harvey "Gizmo" Rosenberg Mdh.
We audiomaniacs by nature are restless, curious and insatiable; ever-horny for more musical wonder in our homes. Just as we think we have crested, the next peak appears in the mist, beckoning.......
"It is better to do it in the front than the rear", is not a moral inflamation about the dangers of kinky sex, but a ancient bromide of loudspeaker crossover designers, which reveals the optimal way for a loudspeaker and an amplifier to make love. This wisdom is completely ignored by the American high end audio community, but cherished by Japanese audiomaniacs. This notion has been around since the dawn of audiotime. If it helps you to grasp the benefits of active tube crossovers versus passive crossovers, think of your passive crossover as one of those thick latex condoms. It is safe, reliable, it will never get you in trouble....but you use it at a very large sacrifice of ultimate pleasure. As my job is to capture your attention for this brief article, let me suggest that the difference between using a tube crossover and a passive crossover is the same as the difference of doing it with or without a radial rubber....which is why the Japanese who relish the subtle are so gah-gah over tube crossovers. Did everyone understand this completely radical way of explaining the experiential benefits of tube crossovers?
May I suggest that those American audiomaniacs who are raving and ranting over the benefits of various incarnation of tip-toes, stands and cables are farting around with low-level tweaking, which is important, but only after the high level tweaking is finished. High level tweaking, according to the Japanese audiomaniac, is getting the interaction of the amplifiers and the individual drivers right, meaning the tuning of the drivers to the amplifiers. Without a tube crossover this high level of refinement in tuning is impossible.
For those suffering with a triode addiction and attend Triode Anonymous meetings, like myself, a tube crossover is a categorical, ontological, epistemological, biological, gizmological imperative, because without it we will never know, and I mean in the biblical sense of knowing, the mystery of triodes.
Obviously, I am championing a triode metacontext, which includes: real triodes power tubes, horns or studio monitors and tube crossovers. These are the three essential elements that are the foundation of the triode ultra-aesthetic.
For those who would risk all for the ultimate musical eroticism...let me reveal t the love making secrets of Japanese audiomaniacs, and how you to can experience the tippy-tippy tip of musical concresence.
Secret One: You must do all filtering at the front end of your amplifier with a tube crossover, or have an input filter built into the input circuit of your amp, thereby eliminating all of the inductors, capacitors, and resistors between the output stage of your amplifiers and the drivers. The inductors in your passive crossovers are the longest pieces of wire in your entire system, and what are their quality?
Secret Two: Use the smallest amplifier possible (power) that will get the job done, and design it so that it is optimal for the driver it is powering. Sooner or latter triodians embrace tube crossovers because they solve problems, liberate and create unlimited expressive possibilities. You probably need nothing more than a one watt amp for your tweeter, a five watt amp for your midrange, and with a big woofer...maybe 25 watts. Personally I believe that after you hit the 20 watt wall in amplifier design it is downhill in terms of refinement.
The Japanese audiomaniac has no trouble creating a four way loudspeaker with four different micro-powered amplifiers specifically designed for each driver. A system that has a combination of push/pull, single-ended, and OTL amplifiers are common...all made possible by using a tube crossover. But the most common system is the simplest : a very refined two way system using an optimal amplifier on each driver.
This will help you understand why there are hundreds of variants of single-ended triodes available in Japan..mostly in kit form. One of the reasons that the 2A3 is loved is because there are at least a dozen variants of this tube which permits the home brewer to select the 2A3 variant that is perfectly harmonious with his beloved tweeter or midrange or woofer. There are legions of rare, arcane, and extinct directly heated triodes to satisfy the most subtle needs, and there is a well developed folklore about which tube and which drivers work best together to guide the novice audiomaniac. Again this high level tuning would be impossible without a tube crossover.
For those whose loins burn with desire for lower distortion, better transient response, harmonic purity, and profound immediacy there is no other choice....and you don't have to buy new speakers , though you need to own more than one amplifier.
Tube crossovers have the capacity to enable a "large scale Stax Headphone type immediacy" that is usually the unique domain (on the small scale) of electrostatic headphones. When the output stage of your amplifier is directly connected to the drivers, layer upon layer of experiential haze is removed.... because your passive crossovers are inhibiting the relationship between amp and speaker.
With both my Tannoy D-15 Mk II studio monitors (96 db efficient), and my Westminster Royals (99 db efficient) I am having an intense love affair; I mean I am hot for 300Bs on the tweeters and woofers, and with four channels of single-ended power I am doing wheelies and burning rubber with a gigantic 4x8 watts. But by using a tube crossover it sounds like I have double or triple the power. If you think I am being hyperbolic, I have often times reconnected the passive crossovers and used one of my hyper-hot rod 500 watt per channel Moscode hybrid tube/fet amplifiers to prove that I am not insane. I am not.
Over the last two decades I have owned and used many different types of electronic crossovers, but it wasn't until the early days of New York Audio that I finally located a LUX tube crossover in Audiomart, which I have used and tweaked for two decades. This crossover hasn't been available since the 1970s. This crossover has been so tweaked that it wags its tail every time I walk into my listening room. But what is today's American audiomaniac to do because there are no high quality tube crossover on the market............until....
Phil Marchand to the rescue. To say that Phil is a Crossovermeister is an understatement. Judging by his catalog he was probably killed in his last previous lifetime by an evil passive crossover and has reincarnated to take revenge on loudspeaker inductors and capacitors. And while Phil makes an extraordinary range of solid state crossovers, it is his tube unit that is the key to unlocking the mysteries of the new breed of triode amps and higher efficiency loudspeakers ....or any loudspeaker for that matter. No let me say that better...a tube crossover will dramatically improve any loudspeaker system that can be modified by removing its internal passive crossover.
And goodness gracious, great balls of fire his tube crossover is a megabargain at $1500, and will never go out of style or be obsolete.
The Crossovermeister has created a brilliant gizmo (and he can quote me), because this is the first tube crossover, to my knowledge, that gives you the option of using Linkwitz/Riley filters, which are 24 db per octave, 12 db slopes, or 6 db slopes. You can only order it as a two way unit. These 24 db slope filters when done with passive parts takes lots and lots of passive parts, and that is where they go wrong: too many parts in the signal path; to many inductors, and capacitors for micro-powered triode glory. These passive 24 db crossovers give coherence but a muddled sound..at least to my years.
What if you have a three way system? Some experimentation will give you the answer, but you want to keep your woofer and midrange/tweeter amps separate, so divide your system where your woofer and midrange cross-over, and let the internal passive crossover for the midrange/tweeter stay in place. A good compromise in a less than perfect audio world. I strongly suggest that you replace what ever inductors are in your midrange/tweeter crossover with either the Solo or Solen speaker inductors. It takes five minutes to swap your stock inductors for these super-duper inductors and they make a big difference in soundosity.
Why is the Marchand tube crossover such an important breakthrough in the audio arts? Because it permits us triode audiomaniacs optimally blend our chosen tweeter triode amps with the woofer triode amps. For example if you are using two 300Bs amps on each speaker you will find a higher level of magic in the seamless transparency of the sound. If you are using a combination of 300B on the tweeter and a 211 or 845 amp on the woofer, you will be amazed at how well they commingle. Or why not blend a 2A3 single-ended amp on the tweeter, and one of those new 20 watt 300 B push pull interstage transformer coupled push pull amplifiers on the woofers (that Gizmo is working on)? Or for those who have a low efficiency speaker and are frustrated because they can't use the Audionote or Cary Audio 300B kit amplifier, now you can use these hyperbargains on your midrange/tweeter.
Words can not describe the sound of Nobu Shishido's WAVAC 805 amp on the woofers and his 300B on the tweeter. What fun listening to $60,000 worth of amp art. Do you sense the fun of experimenting with different amplifiers; searching for the optimal combination that expresses your unique vision of musical oneness?
If this wasn't enough excitement to make your 211 throb with joy, you can adjust the levels of each amp with the individual gain controls so you have complete control over the tonal balance in your system. You sensitive solder slingers know what a gigundo difference in your aural matrix a few db of tonal balance can make. Now that I have you panting, let me use the coup de grace: if you want, you can order your frequency crossover points with 6, 12 or 24 db slopes, and they are interchangeable in about 15 seconds, by popping out little cards that hold tiny little capacitors and resistors.
Let me give you a concrete example of why I gave up whips, chains and dog collars: The stated crossover point for the Royals is 1000 hz. In my Marchand collection of filter cards I have 1000 hz, 1200 and 1400 hz cards in 6, 12, and 24 db slopes. Gentlemen, we are talking about multi-orgasmic tweaking long into the night. This capacity to fine tune a speaker system is essential my evolving audio artification process. The possibilities are endless in terms of tuning your system...sorry I said that wrong...the possibility are endless in refining your tune.
I believe that nothing yet beats 300Bs for harmonic righteousness, yet as I am writing this I am exploring a tweaked version of Ralph Karsten's Atma-Sphere's M-60 OTL amplifiers on the woofers, and 300 Bs on the tweeters, which is giving me the most exciting dynamic, wide sound stage I ever heard on the Royals, with a transparency that is so challenging I am having to see my shrink again. Have you ever heard a combination of single-ended triodes and OTLs on a horn? You better be wearing your audio pampers when you do. This combination may be the le plus ultra of rock and roll epiphany. Every time I change amplifier combination I fiddle with crossover points and slopes...because that is what the audio artification process is all about.
The Marchand circuit uses 12AX7s, and you know what fun it is to play with them. Have you got any 1950s smooth plate Telefunkens in your safe deposit box? Or do those rare RCAs get you off? Get my drift hombre? You can subtly tweak this little joyous mother, by selecting tubes. I discovered a cache of 12AX7s that are twenty years old Tungrsrams and immediately put them in my unit.
Do you own a bi-wired loudspeaker and don't have the courage to go all the way? You could use the Marchand crossover in a non-optimal, though vastly exciting way, by setting the crossover points to where your speakers bi-wire and then using two amplifiers per speaker. This means you could use a small powered triode tube amp on the top section and a more powerful amp on the woofer section....even a solid state one. Voila! because of the gain controls you can match the levels of these two different amps
If you have tweaker DNA in you do the following: remove the passive crossover networks, which is an easy task. I suggest you use the best wire you can afford for rewiring your drivers to the rear terminals. I use AlphaCore Flat Cables. I also strongly recommend the use of Edison Price berrylium copper speaker posts available from Eminent Technology. Loudspeakers manufacturers will usually tell you the crossover points and the slopes, but they will not encourage you to use the tube crossover because, well because, they will be embarrassed. And as you know the most important thing in life is never to get embarrassed.
I would gladly put all of my integrity behind this product. It is the key to unlocking the mysteries of single-ended triode amps and expanding the home aural matrix. Again, our Japanese audiomaniac brothers have been using tube crossover for decades, and it is time for us American audiomaniacs to catch up. I feel so passionately about the value of this product that I have, with great diplomatic persuasion, convinced Tannoy to offer the Marchand tube crossover as a part of new Tannoy speaker concept. All of my friends now own one. Get one and go crazy.
My next article will be about the 10 inch Tannoy Sterlings, which is at the foundation of the Japanese Tannoy cult, which is now available in America..and how to modify it for use with the Marchand crossover, and further speculations on a new direction for OTL amplifiers, and the Futterman Spirit.
Let us now bow our head for a moment of silent prayer for all of our brothers who do not use a Marchand tube crossover. Amen and pass the 12AX7s. Contact Phil the Crossovermeister at 585 872 0982 Fax 585 872 1960. Savvy dealers who want to put on a really great show for their customers will get one.
Copyright 1996, Harvey Gizmo Rosenberg.