Initial Thoughts

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The purpose of this section is to inform the first time speaker builder about my first project so that he/she might make a more informed decision concerning a possible course of action.

I leave out some specific details for three reasons. First, because my writing doesnít approach that of Vance Dickasonís (The Loudspeaker Design Cookbook) or F. Alton Everest (The Master Handbook of Acoustics). Second, repeating what they already wrote would be very time consuming. Third, a first timer desiring an education about loudspeaker construction absolutely must purchase The Loudspeaker Design Cookbook, and would do well to purchase The Master Handbook of Acoustics. Hence, if you are a first time builder and need reification on some issues you will find them in these two texts Ė (mostly Vanceís).

In 1987 I looked into speaker building loudspeakers before purchasing a set of JBL studio monitor speakers. Given the available information available at the time, I didnít think building was a good idea. After all, building my own speaker would NOT approach the sound of a good factory designed speaker.  Things have changed very much since then. The availability of the information is fantastic, and the cost of drivers is very low when compared to a high quality commercial loudspeaker's final cost.

In 1998 I ventured into the realm of good sound thanks to a wife who has very good ears. She played in an orchestra and could easily pick out those components striving to recreate live music. After all, the intent of recorded music is to recreate the live event. The unfortunate part is that many of us (including me) had long forgotten about the sound of live music, so we settle for the sound of a good "recording". My wife hadnít forgotten live music. Based on her advice, we purchased some B&W DM602s1 speakers for $550. After taking them home I was amazed at the improvement in sound quality (accurate musical reproduction) of the little B&W DM602s1ís. They easily bettered the bigger JBL studio monitors purchased 12 years earlier for $600. Music came alive with the new B&Wís. It sounded good (live/accurate) and I wanted more.

I then replaced my Kenwood 125wpc receiver (that clipped at about 35-40 watts), and my Pioneer PDM 205 CD player with a Bryston 3B-ST (a true and good 120wpc), Creek OBH-12, and an Anthem CD-1 CD player. This electronics produced improvements in sound quality very similar to the B&W 602 speakers. At this point my electronics outclassed my speakers.

I read an article about the Hales Revelation 3ís in Stereophile magazine.  Stereophile gave the Hales Rev 3 Loudspeaker pretty good reviews.  This article also indicated what kind of drivers Hales used for the midrange and tweeter. The drivers were some strange company named Vifa. I, like most folks, never heard of Vifa. After doing some internet surfing I found that the midrange driver cost somewhere between $35 and $50. The tweeter driver cost somewhere between $20 and $30. I was astounded. I thought it was almost criminal for a speaker manufacturer to use cheap vifa drivers in a speaker retailing for $2200. The Rev 3's generally cost about $2000+ in stores and about $1400 used.. The reason for this is that they sound very good.  It also takes a great deal of time to build a good cabinet, and a good crossover. The retail markup on this product is 100%.  After some discussion with my wife (CPA) concerning typical markup on any product, and some examination of other speakers available that use drivers available to ordinary folks, I realized that this practice is typical and necessary.  Paying the overhead and wages for a storefront isn't cheap.  I estimate that anything in a consumer retail such as Best Buy, SAMís etc. uses drivers costing between $5 and $20. The huge markup is necessary to keep retailers in storefronts, skilled labor in shops, and income tax paid. However, I was willing to invest the time into researching and educating myself about speaker building.  So the endeavor began.

My initial goal was to build a high quality speaker that would be as good or better than anything in existence. I figured that if the Hales Revelation 3ís used Vifa drivers then I could surely use more expensive drivers and come out with a better sounding speaker. I had aspirations of a three way WMTMW (Woofer Midrange Tweeter Midrange Woofer) design such as Dunlavy. I then decided that I really didnít need to move this much air in my average size living room, so I relegated my idea to a TMW concept. I spent about two months surfing the web and then came across a guy by the name of Rick Craig. I sent Rick an email describing my aspirations, and he suggested that I call him. We chatted for about 10 minutes about what I thought I wanted. The conversation was great.  Rick was, and is, a fine individual through whom I have been richly blessed.

Rick and I cordially discussed a three-way design. He said he would be happy do design me a speaker around two 8" SEAS aluminum woofers, a Vifa Dome Midrange, and a HiVi planar tweeter. The cost would be about $850. We chatted more. He realized my level of knowledge (low) and then he suggested that I buy the Loudspeaker Design Cookbook by Vance Dickason. I told him that I would consider the book and we left the conversation.

Being somewhat cheap, I was reluctant to buy a $35 book, but figured that it would be good education if nothing else. I did purchase the book and poured over it for about three months. It was a good education and more. Vance has performed copious research and testing in this bookís development. This book is truly excellent. It will explain all of the elementary issues of building very good speakers. You could build a speaker without reading this book, but if you are a first timer and want to learn something this text is truly a "must read". The only other must read book in my repertoire is the Bible. Vance Dickasonís book is that good.

I also decided to purchase another book titled. " The Theory and Design of Loudspeaker Enclosures". This book looked similar to the Calculus II textbook I used twice. Unless you are an engineer or mathematician, donít buy this book. I spent about two hours with the book and gave up. It goes through various proofs involved in the box design process.  Argh!

I quickly returned to Vanceís book. During the three months with Vanceís book I contacted Madisound in Wisconsin and requested a paper copy of their product line. The folks at Madisound were very decent, and their catalog had everything necessary to build a good speaker. I then deliberated about what to build. It was really difficult, and I didnít have any sonic reference other than my B&W DM602ís.  I had listened to other speakers, both better and worse, but the B&W 602 was in my living room and I was very familiar with it. I still thought I wanted to build a big three way speaker. After all, to get good sound a three way speaker is neededÖwell?

At this point in my exploration I still hadnít listened to a pair of home built speakers. So before I went on vacation to visit my family in Minneapolis, MN I posted a "help needed" advertisement on the Madisound discussion page concerning my doubts about homemade speakers. Akin to Thomas - I had to hear it before I would believe it. I was again blessed with some willing respondents. A couple of fine gentlemen by the names of Mike Bengfort and Brian Studer (formerly my boss in the National Guard Ė small world) responded. They had built some speakers and said they would be happy for me to audition their speakers in Minneapolis while on vacation. I took one of them up on their offer Ė Mike Bengfort.

A few weeks later my wife and I visited Mike Bengfort back in MN. But before going to Mikeís house in the afternoon my wife and I listened to some Dynaudio 1.8ís($3500 retail) and Monitor Audio 9ís(2,000 retail) in the morning. We listened to these factory speakers in Andover, MN through very good amps ($2500-$4000 retail, Bryston, Sim, and ???), and a Toshiba CD player (not so good). In our opinion the Dynaudio speakers sounded very good, but too polite, and the Monitor Audio speakers sounded colored and bright. They were nonetheless very good sounding speakers, and worthy of their price in the retail market.

Upon reaching Mikeís home in Minneapolis I was increasingly eager to hear what he had built. I was still skeptical that a Vifa/Seas two way could sound very good. My skepticism was soon put to rest. But before I get to the description of the sound, a little background is in order. Mikeís Vifa/SEAS crossover was designed by the folks at Madisound using LEAP and he used North Creek Crossover products in most of it. Since this project involved only a 2nd order crossover the cost of the North Creek components wasnít very prohibitive. My guesstimate is that Mike had about $350 in this project. The astounding thing is that Mikeís $350 speakers sonically equaled the Dynaudio 1.8 ($3500), and bettered the M.A. 9 ($2000) I had listened to earlier that day. I initially figured that the Vifa/Seas drivers in Mike's project would give up substantial ground to the "better" Dynaudio and M.A. 9 (aluminum) drivers, but I was sorely mistaken. Mike B's Vifa/Seas combo produced vocals that were smooth and natural. The bass was accurate and neutral. And the saxophone sounded very rich and clear. My wife and I were both very impressed with the excellent sound that came from a very inexpensive set of speakers. Mike's electronic's consisted of a VanAlstine amp and a Marantz CD player.

Mike also showed me something else of interest. He had a Radio Shack sound pressure level (spl) meter, and a test disk with warble tones on it. He played a 40hz warble tone through his speakers. The spl meter indicated the 40hz frequency was fully  present, but I could barely hear it. I was amazed. Surely 20 hz is the lower boundary of human hearing?? Right?? Hmmmm. I concluded that 40hz was plenty low for any music, and that 20hz is felt, but not heard. I have since learned that 40hz is the bottom end for most instruments, and that a speaker that rolls off somewhere between 40hz and 50hz will provide a very pleasing quantity of musical bass. I learned that a good two way is all that is needed to create good musical sound.

24 Jun 02:  I re-read the above comments and think it is important to emphasize a few things.  Over the last 3-4 years my wife estimates that I have spent 4000+ hours in his hobby.  There are a few reasons for this.  One, the educational aspect seems bottomless.  Two, It is a wonderful feeling to sonically better mega $ speakers at a fraction of the cost.  Three, it is mentally healthy.  This education isn't necessary though.  Building a successful first time speaker doesn't take much time, or require huge education.  There are several viable kit avenues to pursue.  These are listed here.