Books on DIY

[HerbieHightower]

I did some searching here but turned up nothing. What books would you suggest a person get to learn about DIY speaker building? I’m not a novice at woodworking but I am about building speakers. Thanks for your suggestions.

Herbie

[avaserfi]

I did some searching here but turned up nothing. What books would you suggest a person get to learn about DIY speaker building? I’m not a novice at woodworking but I am about building speakers. Thanks for your suggestions.

Herbie

I would suggest looking up AES articles on Floyd Toole as he has done some great research in the field. Also, this trilogy (http://www.audioxpress.com/bksprods/products/bkaa67.htm)of books is a great place to get started.

I would also recommend reading this (http://www.amazon.com/Master-Handbook-Acoustics-Alton-Everest/dp/0071360972/ref=sr_1_2/103-1966872-4787002?ie=UTF8&s=books&qid=1191168669&sr=8-2)book as it will help you idealize your room for the speakers you build.

[HerbieHightower]

Thanks much. Now to get busy and read!

[Guiria]

I bought the "Loudspeaker Design Cookbook" 7th edition a few weeks ago, and while it has a LOT of good information, for me it's not a real easy read and I feel like I'm reading a math book half the time.

I was hoping that the book read more like an instruction manual instead of a theory lesson.

[avaserfi]

I bought the "Loudspeaker Design Cookbook" 7th edition a few weeks ago, and while it has a LOT of good information, for me it's not a real easy read and I feel like I'm reading a math book half the time.

I was hoping that the book read more like an instruction manual instead of a theory lesson.

If you are planning to build speakers and want to do it from scratch you need an understanding of theoretical design before being successful. That explains the nature of these books.

If you really want an instruction manual I would suggest going out and downloading already made plans rather than making your own as successfully modeling/designing and building a quality loudspeaker requires a strong knowledge of the subject that a simple instruction manual cannot give.

[Guiria]

successfully modeling/designing and building a quality loudspeaker requires a strong knowledge of the subject

This is for sure, I wanted to try the DIY route and originally I wanted to build a 2-way speaker but after getting into the LDC book I decided to keep my first project to a single driver enclosure with a small external sub to follow (2.1).

I'd rather build something small and easy with reasonable quality then try something way over my head and have it end up sounding like crap.

[HerbieHightower]

Well, I worked in the electronics field for about 15 years so I have a pretty good grasp on the theory but I don't have much knowledge on building enclosures to optimize sound transfer/minimize harmonics and such. Given the equipment I could probably make the bandpass filters or crossovers but at my age I'd rather just purchase that part. Tuning the enclosures is what I find interesting.

Herbie

[Guiria]

some history of electrical understanding would definitely be useful.

My background is economics and operations so it's all pretty new concepts for me.

[annunaki]

I have not modeled the woofer for enclosure size yet but I am wanting to try The following items as a DIY project:

Woofer (http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=296-412&scqty=2)

Tweeter (http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=264-555&scqty=2)

Crossover (http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=260-140&scqty=2)

The crossover would just be to get me by until I could design a better one myself (higher order roll off). The woofer and tweeter should be a great combo as there are no breakups at the crossover point or for at least a half octave or more on either side of it (crossover point). I would concentrate heavily on enclosure design using quality bracing and I believe I have come up with a way to isolate the woofer from the cabinet as well. All in all it would cost about $265.00 plus enclosure materials ($45.00 est.) and should easily equal anything comercially available around $1,000.00. The enclosure design would be much better than a commercial brand cabinet at that price to boot. What I love about this combo is that it keeps the crossover point nice and low which I have found to be desirable in other systems I have listened to. They are also very close in sensitivity so they should blend well in terms of level.

[annunaki]

Another reason I chose the above driver's is that it allows for a more simplistic crossover design. Hiogher quality drivers require a less complex crossover. The more simple the better in my opinion.

[Swerd]

Well, I worked in the electronics field for about 15 years so I have a pretty good grasp on the theory but I don't have much knowledge on building enclosures to optimize sound transfer/minimize harmonics and such. Given the equipment I could probably make the bandpass filters or crossovers but at my age I'd rather just purchase that part. Tuning the enclosures is what I find interesting.Speaker Building 201 (http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=500-044) by Ray Alden hasn't been mentioned yet. I personally think it is a better book to begin with than the Loudspeaker Design Cookbook. Ray Alden's book is written much more clearly and is easier to follow than the LDC. The first few chapters deal with designing sealed or ported cabinets for optimum bass response, and I think they are the best part of the book.

If you already understand electronics, building a crossover should be easy for you. Crossovers should always be custom designed after a given set of drivers is mounted in a particular cabinet. This requires computer software and a measuring rig. Commercially available pre-made crossovers are almost never a good solution.

There are many tried and tested DIY designs available on the internet. They are essentially in recipe form. You buy the parts, build (or buy) the cabinet, and assemble the crossover. The DIY 2-way speakers in my signature line are my personal favorites, click on the CAOW1 link. I could name others if you want.

[Swerd]

I have not modeled the woofer for enclosure size yet but I am wanting to try The following items as a DIY project:

Woofer (http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=296-412&scqty=2)

Tweeter (http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=264-555&scqty=2)

Crossover (http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=260-140&scqty=2)

The crossover would just be to get me by until I could design a better one myself (higher order roll off). The woofer and tweeter should be a great combo as there are no breakups at the crossover point or for at least a half octave or more on either side of it (crossover point). I would concentrate heavily on enclosure design using quality bracing and I believe I have come up with a way to isolate the woofer from the cabinet as well. All in all it would cost about $265.00 plus enclosure materials ($45.00 est.) and should easily equal anything comercially available around $1,000.00. The enclosure design would be much better than a commercial brand cabinet at that price to boot. What I love about this combo is that it keeps the crossover point nice and low which I have found to be desirable in other systems I have listened to. They are also very close in sensitivity so they should blend well in terms of level.Before you commit to that combination of drivers, you might want to read this article (http://www.speakerbuilder.net/web_files/Articles/xover%20article/xpointmain.htm) that discusses the importance of a woofer's off-axis response when choosing a crossover frequency. I noticed that Aurum Cantus's specs for this woofer don't show any off axis response info. Aurum Cantus is well known for excellent ribbon tweeters, but I have never heard anything, good or bad, about their woofers.

You might also want to look over the John Krutke's excellent web site (Zaph Audio (http://www.zaphaudio.com/)) where he rates many individual drivers available for DIY builders based on his own direct tests. Unfortunately he hasn't tested the Aurum Cantus 7" woofer, but he has this to say about the Vifa XT25 tweeter:Smoothest and most extended response curve in the group, and resulting CSD is excellent. Good tall order harmonic distortion (HD) above 2 kHz, but average 2nd order HD. Poor HD levels of all types below 2 kHz, even considering the extended low end. It may have a 500 Hz Fs, but don't think about crossing it below 2 kHz LR4 (4th order) or 2.5 kHz LR2 (2nd order).Based on that, I would avoid using a 2nd order crossover at 2 kHz with that tweeter.

[Guiria]

Speaker Building 201 (http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=500-044) by Ray Alden hasn't been mentioned yet. I personally think it is a better book to begin with than the Loudspeaker Design Cookbook. Ray Alden's book is written much more clearly and is easier to follow than the LDC. The first few chapters deal with designing sealed or ported cabinets for optimum bass response, and I think they are the best part of the book.

This would have been good to know a couple weeks ago. I was choosing between 201 and LDC and went for LDC for no specific reason.

I might go buy 201 :)

[avaserfi]

Speaker Building 201 (http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=500-044) by Ray Alden hasn't been mentioned yet. I personally think it is a better book to begin with than the Loudspeaker Design Cookbook. Ray Alden's book is written much more clearly and is easier to follow than the LDC. The first few chapters deal with designing sealed or ported cabinets for optimum bass response, and I think they are the best part of the book.


201 is actually part of the trilogy I originally recommended as I see all books invaluable to someone who wants to start building and designing speakers. Although, I will agree with you if one wants to spend just 30 bucks I would recommend 201 first.

Before you commit to that combination of drivers, you might want to read this article (http://www.speakerbuilder.net/web_files/Articles/xover%20article/xpointmain.htm) that discusses the importance of a woofer's off-axis response when choosing a crossover frequency. I noticed that Aurum Cantus's specs for this woofer don't show any off axis response info. Aurum Cantus is well known for excellent ribbon tweeters, but I have never heard anything, good or bad, about their woofers.

You might also want to look over the John Krutke's excellent web site (Zaph Audio (http://www.zaphaudio.com/)) where he rates many individual drivers available for DIY builders based on his own direct tests. Unfortunately he hasn't test the Aurum Cantus 7" woofer, but he has this to say about the Vifa XT25 tweeter:Based on that, I would avoid using a 2nd order crossover at 2 kHz with that tweeter.


I was going to make the same reply, but was trying to find some off axis measurements for the speakers elsewhere online. I just didn't have a chance. With far field listening off-axis response is the most commonly forgotten spec that makes a huge difference in speaker performance.

[Swerd]

This would have been good to know a couple weeks ago. I was choosing between 201 and LDC and went for LDC for no specific reason.

I might go buy 201 :)I'm sorry I didn't speak up sooner.

Before you buy this book, ask yourself if you want to understand the principles involved in cabinet design, or do you just want to make some cabinets that work well. If you want to understand the principles, buy the book. If you just want to make properly designed cabinets, there are several free online calculators, or downloadable spredsheets that do all the math and allow you to easily model several different solutions. Even if you understand all the theory involved, the calculators are probably better than doing the math by hand.

Have a look at these:
http://www.mhsoft.nl/default1.asp
http://www.pvconsultants.com/audio/eq/boxcircuit.htm
http://home20.inet.tele.dk/kou/ubmodel.html

If you have no idea what they are talking about, then get the book.

[Swerd]

201 is actually part of the trilogy I originally recommended as I see all books invaluable to someone who wants to start building and designing speakers...You sure did, and I missed that.

I was going to make the same reply, but was trying to find some off axis measurements for the speakers elsewhere online. I just didn't have a chance. With far field listening off-axis response is the most commonly forgotten spec that makes a huge difference in speaker performance.Amen to that :D.

[annunaki]

Before you commit to that combination of drivers, you might want to read this article (http://www.speakerbuilder.net/web_files/Articles/xover%20article/xpointmain.htm) that discusses the importance of a woofer's off-axis response when choosing a crossover frequency. I noticed that Aurum Cantus's specs for this woofer don't show any off axis response info. Aurum Cantus is well known for excellent ribbon tweeters, but I have never heard anything, good or bad, about their woofers.

You might also want to look over the John Krutke's excellent web site (Zaph Audio (http://www.zaphaudio.com/)) where he rates many individual drivers available for DIY builders based on his own direct tests. Unfortunately he hasn't tested the Aurum Cantus 7" woofer, but he has this to say about the Vifa XT25 tweeter:Based on that, I would avoid using a 2nd order crossover at 2 kHz with that tweeter.

Thanks for the info on the tweeter. I will probably just adjust the crossover point on the basic "fill in" x-over.

As for the woofer, I have not found the off axis reponse charts as well. My choices are not set in stone, it will be more heavily researched by the time I purchase. I am sure I can get some from Aurum Cantus, somwhere.

[Swerd]

Thanks for the info on the tweeter. I will probably just adjust the crossover point on the basic "fill in" x-over.

As for the woofer, I have not found the off axis reponse charts as well. My choices are not set in stone, it will be more heavily researched by the time I purchase. I am sure I can get some from Aurum Cantus, somwhere.John Krutke did look at the smaller 5.5" Aurum Cantus AC0-130. He gave it high ratings, and said this:This mineral filled poly cone driver from Aurum Cantus has an extremely smooth response curve. While there is a breakup around 5 kHz, it is smooth on both sides and easily controlled with a notch filter. Build quality is excellent. The voice coil has venting under the spider, something not quite common at this price point. There is a 3rd order peak in HD at 1.8 kHz which will be audible on some content but probably not noticable most of the time. One negative for many DIY'ers is the squared off frame, near impossible to countersink with normal tools.His general comments about the filled poly cone and build quality ought to apply to the model you are interested in.

While I on the soapbox, my other pet peeve is small speakers that ignore the baffle step problem inherent with narrower cabinets. Commercially available crossovers NEVER deal with this. At one time I was ignorant as to what baffle step was and what it sounded like, but now I find I can easily hear those speakers that don't have compensation (usually in the crossover) for this. I am surprised at how many commercially made speakers fail to fix this.

Read this article (http://www.quarter-wave.com/General/BSC_Sizing.pdf). It does a good job describing the problem and a simple fix for it.

[Guiria]

While I on the soapbox, my other pet peeve is small speakers that ignore the baffle step problem inherent with narrower cabinets. Commercially available crossovers NEVER deal with this. At one time I was ignorant as to what baffle step was and what it sounded like, but now I find I can easily hear those speakers that don't have compensation (usually in the crossover) for this. I am surprised at how many commercially made speakers fail to fix this.

Read this article (http://www.quarter-wave.com/General/BSC_Sizing.pdf). It does a good job describing the problem and a simple fix for it.

So I take it programs like winISD don't take into account the baffle step problem?

Would I benefit from adding the crossover circuit to adjust for baffle step correction even though I'm building a single driver enclosure?

[Swerd]

So I take it programs like winISD don't take into account the baffle step problem?I'm not sure about that and I don't have winISD in front of me now. Probably not, unless it is clearly labled baffle step compensation or BSC.Would I benefit from adding the crossover circuit to adjust for baffle step correction even though I'm building a single driver enclosure?Yes, but it depends on how wide your cabinet is.

Baffle step begins at wavelengths roughly equal to the cabinet width. For example, in an 8" wide cabinet, or 0.667 feet, that would be 1130 ft/sec ÷ 0.667 feet = about 1700 Hz. So the BSC circuit would lower all responses above roughly 1700 Hz by 3 to 6 dB. It really has nothing to do with a woofer-to-tweeter crossover circuit, but it is usually built into a crossover board.

What is the diameter of your driver, and what is the width of your cabinet? Our ears are more sensitive to baffle step in narrower cabinets because our hearing is better in that range. The baffle step caused by a 15" wide cabinet would be less easily noticed.

There is a downloadable baffle step compensation calculator available online at http://soundhobby.com/download.htm

[Swerd]

Baffle step begins at wavelengths roughly equal to the cabinet width. For example, in an 8" wide cabinet, or 0.667 feet, that would be 1130 ft/sec ÷ 0.667 feet = about 1700 Hz. So the BSC circuit would lower all responses above roughly 1700 Hz by 3 to 6 dB. It really has nothing to do with a woofer-to-tweeter crossover circuit, but it is usually built into a crossover board.Before anyone else corrects this, I'll do it. Ignore the above calculation. My number for the speed of sound in feet/sec must be wrong. 1700 Hz just seems too high.

The correct estimation of the frequency of baffle step in an 8" wide cabinet is as shown in Martin King's article 4560 ÷ 8" = 570 Hz.

[annunaki]

Before anyone else corrects this, I'll do it. Ignore the above calculation. My number for the speed of sound in feet/sec must be wrong. 1700 Hz just seems too high.

The correct estimation of the frequency of baffle step in an 8" wide cabinet is as shown in Martin King's article 4560 ÷ 8" = 570 Hz.


I believe it is fairly close. Speed of sound at sea level is 1,116.4 ft/s. You would have to adjust for altitude to be totally accurate. :D

[Guiria]

What is the diameter of your driver, and what is the width of your cabinet? Our ears are more sensitive to baffle step in narrower cabinets because our hearing is better in that range. The baffle step caused by a 15" wide cabinet would be less easily noticed.

There is a downloadable baffle step compensation calculator available online at http://soundhobby.com/download.htm

It is a 3 inch driver in a 9.5 in. tall x 7 in. wide

[Guiria]

Is BSC something that should be considered after listening to the speaker without it? Or should I go for it now while still in the construction phase?

The soundhobby calculator offers different steps of correction which leads me to believe that the speakers should be tested for the actual effects of baffle step before the network is made...which would be difficult to install inside a speaker with a 3 inch hole:)

[warnerwh]

If I were to try designing a speaker from scratch I'd ask the guys at Home Theater Shack and AVS DIY forum. HTGuide also has world class speaker designers and builders.

Designing a speaker, even a 2 way is tough to do right. Crossovers may work with the theoretical ideal if you're good at winning lotteries.

I'm not saying you're not capable but if it were me I'd get some help for sure. You could go through hundreds of dollars worth of crossover parts and still have a speaker that doesn't sound right. Those are good drivers and can conceivably sound excellent with the right box and crossover.

Another suggestion is to just copy a design that someone else did. HTGuide has an area call Mission Accomplished with pics and build threads. The mods there are experts on the subject and there's many who will help.

The one thing you can do though is design and build your own sub. You want a real kick *** sub try a couple of SoundSplinter RL-P 18's in a ported enclosure. Forget the commercial stuff if you want to have fun and save a bunch of money.

Best wishes on your speakers.

[Swerd]

Is BSC something that should be considered after listening to the speaker without it? Or should I go for it now while still in the construction phase?Yes, you should go for BSC in the construction phase. Often when people are designing their own crossover, they listen to the speaker mounted in its cabinet, while a mock-up crossover sits outside the cabinet with wires running inside to the speakers. Crossover parts are simply clipped together without soldering anything yet until a final design is made. Yes, it is necessary to make the crossover board small enough to fit inside the cabinet - not always easy ;).The soundhobby calculator offers different steps of correction which leads me to believe that the speakers should be tested for the actual effects of baffle step before the network is made...which would be difficult to install inside a speaker with a 3 inch hole:)If you already know where you will place your speakers, relative to the wall behind them, you can make an educated guess about how much BSC to use. If the speakers are going to be very close up against that wall, you can skip BSC. If that distance is going to be roughly 18" or more, use the full 6 dB compensation. If the speakers will be somewhere between 0" and 18", try using 3 or 4 dB compensation.