Newb on speaker building, with questions

[Zinsky]

Never built a pair of speakers before, anyway, If I ever did this would be my plan for my ideal homebuilt speakers. Could you guys please inform me of what I'm doing wrong? You can get a good idea of my current knowledge from my "fantasy" speaker design. I have no reason for the peticular frequencies or number of drivers, just from owning lots of different speakers and knowing what I want out of the drivers.

maybe 7-8 drivers per speaker

(1) 18 inch for ultra low frequencies, like 15hz-30hz
(1) 12 inch for low frequencies 30hz-70hz
(1) 8 inch woofer for 70-140hz
(2) 4"-5" mids for 140hz-300hz
(2) another set of smaller mids for 300-1000hz
(1) tweeter for 1000hz-5000hz
(1) tweeter for 5000+hz

just have a crossover for each driver seems pretty simple to me as long as you seperate the bigger drivers so they dont share the air and build the correct volume enclosure. The mids/tweeters don't push much air so maybe I could have them all in the same enclosure. I have most of the drivers laying around. I figure the quality of the individual driver isn't to important if you seperate the frequencies like that. My big concern is having the amp run at 8ohms. How do the major companies with multiple drivers get their speakers to run off of 1 channel? could some one please take me to speaker school easy on the terms, I know you guys know a ton, try to make it easy for me to understand

[Zinsky]

ouch how do you make a paragraph, I'm cringing reading my own post

[Islander]

ouch how do you make a paragraph, I'm cringing reading my own post

You have to hit Shift-Enter instead of just Enter. It's one of the new "improvements".

Your idea of assembling a high-performance speaker out of whatever drivers you have lying around, some kind of box and some kind of crossover makes speaker design sound very easy. I don't believe it's easy at all. For starters, you may have noticed that there are very few, if any, 7-way speakers on the market. Breaking down the audio spectrum into 7 segments may seem logical, but it would introduce more complications than any experienced designer has so far wanted to deal with.

I'm sure some of the other forum members can point you to some informative reading that will be helpful for you.

[ZAKO]

If some of the very best speaker designers have stayed away from seven segment designs,,,What makes you think you can do any better?? As Paul Klipsch once said "" HO HUM " Another break through "

[Zinsky]

did you read what I said you illiterate ****?

despite the fact that I always think I can better then someone else, and that I am successful in everything I do

instead of making stupid comments like that, just answer my damn question. I clearly stated it was a "fantasy" speaker setup, and that I have little knowledge, and I wanted people to tell me what was wrong with it.

[michael hurd]

I am not trying to burst your bubble. There are a few things that would be difficult to address.

First of all, there will be overlap between the different elements ( woofer to mid, mid to tweeter etc ). Having such a small bandwith for each device sounds tempting, but without extremely steep slopes you will have multiple devices radiating at once, and you will have comb-filtering, wildly changing phase and amplitude.

You could address some of these issues with active crossovers, but you would require multiple units to accomplish that, along with multiple channels of amplification. Then there is the issue of matching ( time alignment ) between each device, so that there is a coherent wavefront without delay. ( and phase changes that go along with it )

You would also need to try and keep each device from beaming, so that the polar response does not change radically from one device to the next. This is a function of element size and frequency.

Without measurement equipment, and a lot of understanding of theory, I would keep the number of radiation elements to a minimum IE: 2 or 3 way. You may also want to build a textbook design that has been tested, and go from there.

[G.Kennedy]

did you read what I said you illiterate ***?

Wow 2nd post ... pretty bold. FYI, you may wanna lighten up ... maybe decafe' .... and calling peeps illiterate, while you are not using capitals in your sentence structure makes you look ..... well ... illiterate.

......... I am successful in everything I do

I am confused, if you are successful "in" (should be the word "at" ... you illiterate or what .....) everything you do, then you should be able to do it on you own with out asking questions ... just go to your shop and slap it together. It's guaranteed to be great ..... cuz your "successful ....in.... everything you do"

Your gonna make tons of friends here ... you seem real smart.

[DrWho]

Where are the horns?

As far as the nominal impedance, the crossovers take care of that for you.

[Guest " "]

The volume requirements for the first few drivers would be pretty large in order to operate in the range your targeting. There are certainly more compact designs that would perform as well or better.

There may be significant cost to finding a 12 inch woofer that can acutally deliver significat volume at 30hz.

Same for the 8 inch woofer at 70 hz.

The only item you are even close on is keeping the 1000hz - 5000hz range on one driver.

Your going to put yourself in the nut house trying to match the SPL ratings of 7 drivers.

Aside from all the alignment issues.

[DizRotus]

This thread reminds me of callers to Dr. Laura's radio program (or similar call-in shows) who are surprised when Dr. Laura (or similar hosts) reams them a new one. Don't the caller's listen to the programs and hear what is said to other callers with similar problems?

G. Kennedy's comments are spot on.

[Daddy Dee]

Zinsky,

Welcome to the forum.

I remember a buddy in college who purchased a used diy project similar to what you are imagining. The builder had done an excellent job on cabinet construction and the speaker was neatly executed, but the sound was disappointing. I'm a really non technical person and don't completely understand the issues involved, but they are many. From visiting with a few Klipsch engineers, I have come to understand that speaker phase changes with crossover slopes and this is a problem in speaker design. More drivers means more phase issues. It's a significant problem for engineering types. For casual diy types, it's nearly insurmountable.

Some possible alternatives, which I think would be enjoyable, 1.) build from a kit which has had engineering considerations thought through.

2.) Build a single full range driver speaker. Check out threads on Fostex and full range driver. These things sound amazingly good. There are several forum members and engineering types who swear by these simple designs.

3. Pick up a pair of Klipsch Heresy on Ebay. It's a nice three way design and a great platform to learn from. Sort of the audio version of a shade tree mechanic's dream. Vintage Klipsch needs some TLC to get back to spec and they are fun to work on, too. I have lovingly restored a number of these sweethearts.

[Coytee]

maybe 7-8 drivers per speaker

Maybe just buy some bose 901's and call it even?

[]

[Daddy Dee]

Coytee,

You are a funny man!

[djk]

Here's exactly what he is looking for, and it will sound good too.

Bass

http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=5,602,367.PN.&OS=PN/5,602,367&RS=PN/5,602,367

Mids and Highs

http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=6,411,718.PN.&OS=PN/6,411,718&RS=PN/6,411,718

Ten, count 'em, ten drivers to cover the full audio spectrum.

[Professor Thump]

Zinsky,

I appreciate your enthusiasm on an ambitious “Do It Yourself”. The beauty of audio design is that there is no one correct answer but generally speaking there are logical directions to designs. Everyone hears differently thus if it works for that individual, more power to him or her. Some of these loyal Klipsch forum debaters have been on this forum for a long time. I suspect that they would prefer that you read some of the dialogue already printed because there is a lot of good information in the previous threads. None the less don’t let them discourage your ambition for excellence whether it is correct for others or not.

Designing a system with 8 sources is analogous to walking eight dogs with eight leashes. It is hard to keep them from tangling lines with one another or fighting. The same thing occurs with multiple sources that do not share a specific bandwidth…all the drivers do not get along well since each driver has a specific phase angle with reference to a given point. When you have a 10 foot array of speakers for near field this is a mess. The outside drivers are farther away thus delayed in phase. Please don’t underestimate the significant of this.

It would take me a bit of time to count how many speaker systems I have designed, in my 20 plus years of work, but the number might be approaching 100 designs that came to fruition. So I have been around the audio block a bit. I have guidelines that I use in addition to Paul Klipsch’s. Most of you probably know that Paul Klipsch had 4 rules of optimization that he followed when designing a speaker:

1. Efficiency

2. Directivity

3. Distortion

4. Response

There is one rule that I have added to the list.

One source is best…

Every design has its limitations… so do single sources. But in general one good source is better than two moderate quality sources. Before you judge consider this. If you had a perfect system it would be a point source, i.e. no size and it would be full range with no distortion and optimum dispersion characteristics. Wow! Great! Sign me up. Unfortunately the laws of physics kick in and limitation do occur with this concept. I have heard a single 6” speaker that did sound very good and was relatively full range. It was designed by Keith Yamagishi who is one of my most respected engineering friends from Panasonic. It had two limitations:

1. Power – the voicecoil was small and the cone light so it had limited power capacity.

2. Directivity – Being a 6 “ driver it beamed above 1 kHz so the sweet spot was limited. More laws of physics. 2Ka is where the dimensions are bigger than the wavelength thus the dispersion narrows.

So now you have the first two problems with my rule. It won’t get loud and there is only one seat in the house. Most manufacturers ignore the second issue for dispersion and sometimes the first one for efficiency. Both are important.

So where does that leave me? Well I have no choice but to go to a two way design. So I have traded a seamless midrange with a single source for more SPL, lower distortion, and the potential for controlled directivity and flatter frequency response. All we need now is a perfect crossover and a perfect waveguide. Easy right? Not really.

So now I have to amend my rule of single sources. The new rule is:

Make each driver as good as possible.

If you don’t start with good drivers the rest of the design is useless. I can’t stress the importance of this enough. No crossover will weed out all the defects of a driver. That is why we spend so much time at Klipsch designing optimum drivers for each system.

Crossovers are great. They are the soul of the voice, the sonic personality of the design. I think they are the funnest part to design but they are a compromise to a single source because the speaker system is now more complicated thus the problems are more complex.

At Klipsch we can take weeks or months to design a crossover. Some we get lucky in do in one day, but complicated ones where we can afford a lot of components are very complex. Just ask Chris, who is working on the voicing for Palladium. You can do the fundamental designs and listen to it. Once you hear things that need improvement you go back to the anechoic chamber and consider the multitude of options you have in improving the voicing. Needless to say it is complicated.

The more sources you have the more complicated the problems. Now you have to phase align more sources. Every time the sources are 180 degrees out of phase you have a cancellation to the response. The sound is there but it is spread out in the room somewhere because it is shooting in another direction. This is why a voice may sound harsh or unintelligible. So in general I will minimize sources.

Now for those of you who know me, I love pro sound systems with horns and I like bass, which means I like woofers…lots of them. The more 18” drivers you have in a live sound PA the better the base is. The THD is lower and the attack is tighter. So this contradicts my first rule.

Here is why… Distortion

I love headroom. A lot of people have never really heard bass with clean headroom. Live sound with a PA is usually the only way you will. So to have a personal system that can give you that level of attack is special.

So to get back to your discussion… IMHO you are using too many crossover points. It will be too complicated. One or two is better. If you want more headroom focus more on multiple drivers in the throat of one horn. That way the multiple drivers look like one source and your power levels go up. Multiple subs will sum well but don’t go above 100 Hz or so. That way the wavelength is much bigger than the distance between drivers, so they look like one source.

[Mr. RF62]

Prof. Thump... Thanks for all that information, I revamp older speakers systems, and consider myself an amature, and always will. There is soo much to learn and remember that ... well... I love it. You have prolly forgotton more about speaker systems than I have learned but more information like this from you and I'll be happy. I like Pro Audio as well, and it was a very interesting read and the ending of not going over 100Hz, spaces between drivers and sounding as one source.

[Y]

SB

[ZAKO]

A journey begins with the first step,,,Unless your standing in front of a open manhole.

[Marvel]

A journey begins with the first step,,,Unless your standing in front of a open manhole.

It's still a journey, Maron, even if it goes down...

[Zinsky]

holy shit, I was not expecting such informative responses. Awesome forum guys! thank you very much for your posts, I will do some more research based on your posts, and get back to you with more questions. Hopefully I won't be too active, I fear I will end up spending too much on equipment if I kickstart my audio obsession from my younger days lol

[Guest macbeth]

Zinsky,

My two cents:

If you're really new to DIY audio, start with an open baffle full range driver stereo pair (google single driver speaker designs - there's a forum for this). From there play around with the location of the driver on the baffle (golden ratios, etc). It's a very cheap way to get started, and very cheap way to get the hang of listening for differences. Stick with this for a while - you'll learn alot with only a few variables (driver geometry, maybe one or two different drivers - use the cheapies for now!!!).

Once you get something good (good full range open baffle design and good room placement, etc). Next, get a couple of decent, but cheap tweeters and work on crossovers - make it easy to make quick changes. Compare different order 2-way filters with different topologies. This simple excersise will get you used to calculating, changing and listening to different components. Stick with this for quite a while.

At this point you have invested <$100 and a bunch of time, but you will have learned quite a bit about diffraction, drivers, crossovers, placement, etc. You'll also have an amazingly good sounding pair of speakers, that are only lacking low end.

This should take you a couple of months - after this you'll be ready to make a 3-way with a sealed woofer. You'll soon learn baffle step loss and 3-way crossovers. This second investment of $100 will get you down to a good 80Hz. This is where it gets REALLY good . . .

Start slow, take your time, and most importantly:

HAVE FUN!!!

Matt