Phase Coherence or Time Alignment: Which More Imp?

Though my own sensibilities lie with Roy, and the very cogent points he put forth, I want to make it clear that as Jeff Joseph basically said, there's more than one way to skin a cat. Jeff's speakers have established themselves as fine a loudspeaker as one can find in this hobby. I admire and respect both he and his products.

I'm really having a great time watching the discourse in this thread!

Larry, I am happy to hear you were a friend of Bud's. I really do feel an emptyness in his absence. I am honored by all of which is being written about him here.

What I personally feel is Bud's greatest gift to us is his lifetime of continually improving the craft that so many of us (Jim Thiel, Jeff Joseph, Larry Staples, Richard Moddafieri, Ray Kimber) have immersed ourselves in with all of our hearts.

It is true that Bud was outspoken, opinionated, and could be downright ornery. However, for those capable of seeing the truth, he dedicated his life into laying the foundation which we all could build upon. He knew that life was finite, but also knew that the art/science would never cease. His hope was for us to learn from his life experience - all of the work, successes, mistakes, etc. to build upon his lessons learned so that we did not have to reivent the wheel. Seeing people ripped off by shamanism or BS would enrage him. If that ruffled feathers along the way, I can think of no higher compliment to pay the man. For those who he came to become fond of, there was boundless fun, humor, respect, generosity, and love.

While I believe and am invested in first order series crossovers, low Q drivers, transmission line loading of the bass and midrange drivers, and time alignment, who am I to say that another approach is not without merit? Again, there are so many fine sounding speakers, in many different flavors, that we can respect those who have faithfully dedicated themselves to the craft.

As Larry alluded to, Bud Fried did produce time aligned speakers. He sure was a proponent.

Skrivis' C/3L speakers are time aligned, along with the simple first order crossover he stated. They also use true transmission line midbass loading - which is actually MORE important that loading the woofer that way. I'm sure he'll agree that the notes just flat out fly out of the speakers, with no smearing whatsoever. I really like my pair...

Larry, I am certain your speaker venture will be a successful one. Best of luck! Please let me know if I can be of any assistance at all,
Joe

Hi, Tom.

Please forgive me for not fully understanding your question. From what sense do you mean, "a true series crossover has to to pass all the information sent to it by the amplifier, unlike most every other crossover design?"

To be honest, I really have no idea why the series crossover is not used more. Despite the "black magic" that surrounds crossovers, this one even being on another plane, it is no more complex or difficult to understand than a parallel network. Though, I would allow that the most simple first order parallel network (cap inline with the tweeter, plus coil inline with the mid/woofer) is probably the most easy for folks to envision.

What I think sometimes scares people is when they see the schematic of a series network. It looks all wrong on paper, as our minds have grown accustomed to seeing the cap go with the tweeter, and the coil go with the mid/woofer. With a series network, the same is true, but it took a very simple parable that talked about what was actually happening before it clicked for this dunderhead. Of course, I sound ridiculous in this post, because I cannot draw out a parallel and a series network, and I wish I could. Suffice it to say that it looks odd, with the coil in parallel to the tweeter, and the cap in parallel to the woofer.

Bud got started down the series crossover road while at one of his visits to Dynaudio. In talking to someone, he noticed two crossovers on their desk. Bud being Bud, he asked about them. The employee mentioned, "Oh, they're different. These are the series crossovers and these are the parallel." Bud asked what was different about them, to which the reply was, "Well the series crossovers are just better. Both from a sonic and measurement standpoint." Of course at that point, Bud's question was, "Well then why the hell do you even offer the parallel crossover?!?" The answer was, "Nobody wants the series crossover because they've never seen them before, and whenever we send them a diagram, they run away."

Again, Bud being Bud, he didn't run away. He built them, tested them (and saw their much superior dynamic range), listened to them (musicality plus cohesion - less sense of listening to individual drivers), and soon after never built another parallel network outside of to have something to show as a comparison for testing or at shows for dealers, customers, friends.

What was even a surprise to Bud was when I used to discuss them with him last year. He never heard of Zeta, which is the means to alter the rolloff and sonics of a series crossover. The traditional first order Butterworth (6 db/octave) values of the parallel network yield the same 6 db/octave rolloff have a Zeta value of 1.0. By altering the cap/coil values in relation to each other, one can lower the Zeta (for example - 0.7, slower rolloff - more laid back sound) or raise it (1.2 faster rolloff - more upfront sound). He never heard of this before, and nothing made him more happy than discourse he found interesting. It was something that he wanted us to experiment with together. Alas, he fell ill before we got to play...

I hear in the series crossover a sense of cohesiveness that I instantly noticed each time I listened to the Roman Audio Centurions. The Centurions use Ray Kimber's patented DiAural Crossover, which is just a simple series crossover - though I have never looked at the patent. As Ray was another one of us Bud Fried proteges, I consider it a homage to Bud. Anyway, the sound of these speakers just knocked my socks off. They were creamy, smooth, yet detailed and dynamic. Musical, and I realize that is a vastly overused term. The cohesiveness in the sound haunted me. I could not stop thinking about them. I later understood why, it was the series crossover, the drivers act in unison, as opposed to working on their own.

Nice post, Larry!

Only one thing, I'm sure that Bud is turning over in his grave right now regarding your feeling that he went to Princeton. As you will well remember via this prodding, it was "Fair Haaaaaaaaavud".

All I will add is that he was truly a member of The Greatest Generation. During his time there, he received every degree they offered, medicine and dentistry excepted. Though he was frail later in life, his energy, enthusiasm, and confidence, and wit would put any 23 year old to shame.

I am a better person because he befriended me. He and football great Johnny Sample have both made indelible marks on my life.

Nice post, Tom!

I think one can argue from a lot of different perspectives, it makes for interesting conversation and enhances everyone's experience here. However, when one tries to say that something that has been to be viable (and over an extended period) "cannot work", one sure puts themselves in a difficult position.

As I reread through this thread, I am more than embarrassed to have noticed that I was flat out backwards in my Zeta description. Zeta of 0.7 is more forward, and 1.2 is more laid back. Can't believe I actually made that mistake in the morning! Surprised no one crucified me on this. Mea culpa, mea culpa...

Again, for anyone who doesn't know, I am a part of the current Fried loudspeaker operation. I needed to get involved because of my feelings for Bud.

Suits_me, I was also thirsting for the information you are seeking at one point. I could not read enough about the Frieds. Thankfully, a significant amount of this can be found at http://imf-electronics.com/Fried/index.html, including the C series of pyramidal, time aligned minimonitors. There are a lot of pdfs of old sales literature. Amazing how quickly and profoundly the computer has impacted this area, most everything here was typewritten and mimeographed.

I have Bud's personal pair, and sure enough, they have been tweaked and tweaked, but think that the pair Skrivis owns are probably not all that different sounding. They have an uncanny ability to produce music without so much of the resonances that we never notice until we have a pair of loudspeakers that don't produce them. Also, as someone who has been around enough audio equipment as I have, to find a pair of speakers that image as these do really leaves one impressed. I also have the matching O subwoofers that they sit on, but don't look anything like that on the website, as they switched to a design that was narrow and deep ala what is currently in vogue.

I think you'll agree with me when I first perused the site that the description of the man literally being a generation ahead of his time was accurate. Alas, there will NEVER be another...