The mistake armchair speaker snobs make too often

@fleschler 

Activated charcoal bass filtering? Exactly how are you implementing this?  

@kota1 ,

I think my definition of imaging is different than Mr Clearmountain's. With what he is trying to achieve he is correct. A center channel will improve the results. It will provide the best two dimensional image for the largest number of people (locations), a wide "sweet Spot." I am looking (listening) for something different. A center channel interferes with the formation of the third dimension. People talk about the third dimension even though systems that will produce it are rare, very rare. In my own experience since the early 60's only four systems have achieved this level of performance. The first one was the system of a high school music teacher in an apartment in Coral Gables just South of Miami, FL in 1978. It was based on Sequerra Metronome 2+2W loudspeakers and Threshold electronics in an irregularly shaped room with blankets and bean bag chairs tossed haphazardly throughout. To say I was in awe is an understatement. The second was an HQD system at Sound Components in Miami shortly thereafter. Peter McGrath ended the listening session by frying a Quad with an organ piece trying to impress a customer with the bass performance. Not me! I was not qualified for such a system.  I was in awe nonetheless. It took me another 15 years to get my own system to perform at that level and another 10 years to fully understand what I was doing. #4 is the system of a friend that is relatively modest it relies 75% on DSP to achieve these results. I am working with another friend on a 5th system based on Magico S7 loudspeakers. 

I have said this in other posts, experience is king. You have to hear this to understand it.  It is one thing to get a system to sound good. It is another issue to get it to image properly. You can get a fine two dimensional image out of a poor sounding system but you can not get a good three dimensional image out of a poor sounding system. You can get a wide sweet spot with a two dimensional system, but there is only one sweet spot for the third dimension and you can hear this by simply shifting your head side to side. Certain issues like a bad crossover design will permanently preclude  a system from getting that third dimension. Variances in frequency response between the two channels is another common factor that prevents a system from achieving that third dimension. This is why measuring a systems amplitude response is so important, but you also have to have the ability to alter amplitude response without adding distortion, DSP again. Group delay is  another issue. Then there is room acoustics. That third dimension is the most fragile of all audio characteristics. All this is a great argument for active loudspeakers and we have had the capability to make any loudspeaker "active" since around 1995 with the foundation of TacT Audio. TacT is now Lyngdorf and other companies have entered the market such as Trinnov, Anthem, Legacy and my personal favorite, DEQX.

@erik_squires .

The single most expensive part of speaker manufacture is the laber by a huge margin. As an example my subwoofers use about $1000 worth of parts, drivers, and materials. One subwoofer enclosure has 168 hours of labor start to finish. Shop time is now $200/hour. This comes to $33,600! Retail is around 3 X parts and labor = $103,800 for one passive subwoofer! With modern tech in a shop set up specifically to make these subs will find efficiencies that could cut these figures in half. The best you could do would be $50,000 MSRP. This is why with rare exceptions you can not find a well built subwoofer in the commercial market. The entire construction process will be cataloged on Imgur when I am finished. 

As for regular loudspeakers, the secret of fantastic audiophile speakers is not in the drivers. They are a dime a dozen. The secret is in the enclosure and crossover design. The DIYer has limited access to the kinds of test equipment needed to design SOTA loudspeakers but even now, advancements in computer and digital technology are making the speaker designer obsolete. You can have a preamplifier with a full 4 way digital crossover, room control and EQ. All the computer has to do is measure the system via a microphone and in 10 seconds you can have a perfectly designed loudspeaker for your room. You still have to build an enclosure that is functional  and hopefully attractive, so there is work for the DIYer to do and be proud of. 

JBL made a bunch of clinkers, they all did including Klipsch. Paul Klipsch came up with the center channel because his K horns had to go in corners which in many rooms were to far apart creating the famous "Hole in the Middle" WIth a center channel you could close the hole and make even more money. The center channel then spread to systems that did not need it just to make more money. A properly set up system does not need a center channel, even for movies. 

Todays loudspeakers are way superior to any of the older units due to modern enclosure design concepts and test equipment. 

@erik_squires 

Exactly. I am trying to put it into the perspective of a commercial operation where the cost of doing business is inflated by Insurance, employee benefits, wear and tear on equipment and tooling etc. Since I own my own shop and I am the only employee I just have to worry about wear and tear on the machinery and tooling. I could make the subwoofers in small quantities for considerably less which I am not going to do. I am publishing the process in case someone else wants to try making a similar enclosure.  See enclosures here https://imgur.com/gallery/Q4uR1s3

All this backs up your thesis that an individual with skills, modern drivers and digital technology can make a very competitive loudspeaker. 

@kota1 ,

This was a topic of much debate back in the 70s. Those of us in the minimalist camp (the no tone controls crowd) were convinced that with the really good systems the center channel was detrimental. From the purist perspective it is. The center channel disrupts a systems potential for forming a proper image from the ideal listening position. It steals the magic. What the center channel does do is help a system form a satisfactory (no where near ideal) image from positions off center. The term many people use incorrectly is " a wider sweet spot." The end result is that it corrupts the actual sweet spot. There is no such thing as ideal imaging away from the actual sweet spot. However a system with controlled dispersion using linear arrays can provide a satisfactory image up to about 15 degrees off center while preserving the very best image dead center. This would include three listeners ( a 3 person sofa's worth) at the distance of the sweet spot, satisfactory for theater. This is the reason I have two rows of seating in my media room enough for 6 people to enjoy a movie. As far as audio is concerned three channel recordings are of no consequence as so few are and will be available. Analog R to R machines are a total waste of time and money. All you have to do is buy the 24/ 96 or 192 digital file and you will have spent eons less on a superior program source. 

We just watched the movie "Tar" starring Cate Blanchett. A very strange movie. The acting was wonderful but not a movie I would recommend to friends. 

@kota1 

Quadraphonic died rapidly because the technology at the time could not do it without marked compromise in 2 channel performance. To the serious audiophiles of the day it was a seriously bad joke. In the end it's sole purpose for being was to sell more equipment. Even now that the technology exists to do "surround sound" well, people interested in the highest levels of performance regard it strictly as a theater stunt. There might be a method of using two rear channels to enhance realism that I plan on exploring once I have the necessary equipment. The size of a venue from a sonic perspective is indicated by the delay of "late" reflections. The longer the delay the larger the venue. Two rear channels playing 40 to 50 dB down can be digitally delayed any period required to reproduce venue size from a jazz bar to a large indoor stadium. This could be used to increase the realism of live recordings without hurting image formation at least theoretically. 

If you have decent ears I can prove to you in a very short period of time that a center channel detracts from 2 channel image formation at its highest level. 

While I think it is totally unnecessary to spend the ridiculous money some people spend to get the highest levels of performance, you still have to spend quite a bit more than most people are willing to spend. I think there are very viable short cuts one can take such as building your own loudspeakers as long as you are willing to invest in the appropriate measuring devices and digital signal programming of crossovers and EQ. Avoid Vinyl if you can and put the money into a computer and large SS hard drive. This is a seriously more cost effective approach to collecting music. Hi Res streaming has also come a long way and is excellent for discovering new music.

Forget about Sony. My old TacT processor finally died a permanent death and my new DEQX Pre 8 is still at least a month away. Living without music is not an option so for $1500 I got a MiniDSP SHD preamp and UMIK-2. My old Tact in todays money would cost $8,000 -$10,000.  The SHD is not quite as transparent, but it does Room Control and subwoofer crossover every bit as well. With LS3 5As an amp like the Benchmark AHB2 and two subwoofers you can make a seriously high performance system. Higher than anything you could do 40, even 30 years ago.

@kota1 

I guess you are very much like me. We never sleep:-)

First of all we need better definitions. I am referring to 2 channel systems. I have a 2 channel system , but it is comprised of 6 individual loudspeakers forming a full bandwidth line array. 

When I refer to "good hearing" it is not just the measured performance of the ears themselves, but also the training and interpretive powers of the lump connected to them. Not a problem. Once exposed to such a system you will never forget it. I still have vivid recollections of the High school teacher's apartment and system. 

I must be a fool then. With your eyes closed playing a 24/192 version of a great live recording like Arctic Monkeys Royal Albert Hall or the perennial Waiting for Columbus, the only audio clues that you are not at the real performance is the crowd noise coming only from in front of you and an image that is much too good for a concert of this nature. Playing music this way is for demonstration purposes only. Running at such a volume on a continual basis is not good for your ears or your marriage. My house is an open design with very few doors. The media room essentially exits into a large cavity. There are enough late reflections to convince the brain that you are in a larger venue or not necessarily in a small one.   Playing classical music or acoustic jazz is probably a better, safer indicator and will produce the same results. 

Immersive sound? Do you sit in the center of a band or orchestra?  Immersive sound is for theater use. My system does double for theater use but I am not willing to compromise it's 2 channel performance 

@tvrgeek 

I build speakers also and relative to the enclosure, drivers are inexpensive. The driver market is huge and there is lots of competition. Take a Big Wilson. All The drivers might cost say $10,000, probably a lot less. However, the speaker pair retails for $350,000. For the sake of argument let's break this into 3rds, the actual cost of the speaker including labor and associated costs, Wilson's profit and lastly dealer's profit. That would be 117,000 each. The actual cost of the speaker minus drivers would be $107, 000 

My point is that relative to making a speaker enclosure the cost of drivers is minimal even with a very inflated figure. It is difficult to spend more than $2000.00 for the drivers of a two way system. The best subwoofer driver for my purposes cost $256.00 each. After all the work on those enclosure I am not about to put a second rate drivers in them and I  investigated the entire market before putting pencil to paper..

As for crossovers Eric is correct that the active approach is superior in every respect and easy to implement. The active part need not be in the speaker itself. Outboard equipment is seriously superior and electronics companies are starting to get the message. DEQX has a preamp coming out that has a complete 4 way digital crossover which is extremely flexible giving you a choice of filters from 1st to 10th orders, butterworth or L-R. in 1 Hz increments.