DIY Speaker Design - Resources

DSK · « **on:** 29 Mar 2005, 01:42 am »

Hi all,
I'm interested in learning about speaker and crossover design. I don't have the time or funds to build a series of speakers, each hopefully better than the last, in order to get to one I am happy with and can live with for a long time. I would rather study everything available on this science/art and then use well-proven concepts to build a high-end speaker. Obviously crossover tweaking may be required to optimise the design, but I imagine that by using high-end and well matched drivers (that are known to work well together) and well designed boxes to match the drivers, that a very good speaker could be built on the first attempt. Initially I'd probably use passive crossovers, perhaps later moving to something like the DEQX (when funds permitted).

However, although there are numerous DIY speaker kit websites with snippets of useful info, there doesn't seem to be any websites or design books that cover all of the concepts and principles of speaker and crossover design. Vance Dickason's "Cookbook" seems to be the most often quoted reference but seems widely criticised as not being sufficient to enable someone to go out and design and build a pair of speakers. Apparently, it doesn't give any real info on how to select and match optimal drivers, or optimise box design to match the drivers, etc etc.

I'd love to hear your thoughts on this book and others, and any other sources of relevant info you can point me to. How did you experts out there get up to speed?

I figure there are probably a lot of others in the same boat as me that would find this information extremely useful.

_scotty_ · « **Reply #1 on:** 29 Mar 2005, 02:43 am »

Unless you make the necessary investment in measuring tools,[ie LMS, CLIO,
etc.} you are better off building a pre-exisiting design off the web or a kit.
If you are rolling your own you have to have the ability to measure the results of your efforts.when it comes to driver matching,crossover design, and complete system behavior. Without the ability to measure what is happening you stand a real good chance of building a bad sounding piece of crap and not knowing why it doesn't work like you thought would. Scotty

DSK · « **Reply #2 on:** 29 Mar 2005, 02:48 am »

Quote from: _scotty_

Unless you make the necessary investment in measuring tools,[ie LMS, CLIO,
etc.} you are better off building a pre-exisiting design off the web or a kit.
If you are rolling your own you have to have the ability to measure the results of your efforts.when it comes to driver matching,crossover design, and complete system behavior. Without the ability to measure what is happening you stand a real good chance of building a bad sounding piece of crap and not knowing why it doesn't work like you thought would. Scotty

Thanks Scotty. I currently have ETF5 but would consider investing in additional measurement s/w if it meant that I could build a pair of speakers for say $5k that outperformed most speakers up to say $10k.

Kevin P · « **Reply #3 on:** 29 Mar 2005, 03:02 am »

Dan Wiggins is going to offer a design course within the next couple months. We are going to document the information on our web site as a resource for those who want to learn more. You do have to invest some money in measurement gear & design software to get serious though. A good measurement set-up and some design software opens up the door to have a lot of fun.

It is pretty much imposible to consider trying to design something without these tools. I don't know how they did it in the "old days". The DIYer can purchase a first class measurement/modeling system that would have made most large companies drool 10 years ago. Knowledge of the tools as well as some acoustics and electronics is necessary to take advantage of it though.

_scotty_ · « **Reply #4 on:** 29 Mar 2005, 07:25 am »

DSK, If you haven't already already purchased the companion mic/preamp
and the IMD/THD/Multitone distortion component you should do so, you will need these items. A great place to start learning how to build a loudspeaker
would be to design and build a inexpensive 2-way loudspeaker. As a design exercise you could try out different filter types and crossover frequencies
and measure the results. This would tell you what effect a given decision about crossover frequency and slope has on the frequency response. It will also tell you something about how accurate any crossover and box response software you might using is at predicting realworld results. The ETF5 software overview does not say that it is intended as a loudspeaker
design and measurement tool. Others on this forum who design loudspeakers professionally may be able to suggest more appropiate software for your application than the ETF5.
Scotty

Harry P · « **Reply #5 on:** 14 Apr 2005, 01:54 pm »

Home Theater Forum has very busy sections for DIY. The Madisound bulletin board is also a great resource.

mcgsxr · « **Reply #6 on:** 14 Apr 2005, 04:00 pm »

All mentioned so far are great, but I would also recommend reading Steve Deckert's musings on DIY speaker design on his site - an excellent read, and a good gut check.

I still build speakers, and they still please the owners (some are for me, others for friends) but it was well worth reading.

I would personally recommend any of the kits from Dennis Murphy, and came really close to building his Usher 2 way last year.

Then I discovered the fun of full range drivers - now I am saving for a set of Visatons B200's, for an open baffle experiment.