Active speaker DSP test bed -- enough interest?

[neildavis]

There is a somewhat old version at: http://www.audiodevelopers.com/Software/ASD/setup.exe. You can play with that version to get a feel for what it does.

I need to post a new version that has a lot of changes, but I've been waiting until I'm done updating the USB interface code. The original software was dedicated to the FTDI USB chip that was the defacto standard several years ago, and it was before Arduino boards were around. There is a newer version of the software that I could post that will work with Arduino boards that use the FTDI chip. But now most of the Arduino boards are using the Atmel chip, so I want to change the USB interface code to be more flexible and not dependent on the FTDI driver. I'm working on it...

[Kornbread]

Wasn't there a download of ASD available somewhere?

[Jonathan Anspach]

I'm very interested.

[evilskillit]

I just finished reading the PowerPoint and the whole thing is very interesting. I can't wait to see where it goes.

[bjaurelio]

I just took a cursory look at your website and am extremely excited. I've been mulling over an active design in my head for awhile now. We just moved half way across the country and are now in the process of buying a house that we hope to be in before the new year. Hopefully I can convince my wife that I should build an active stereo system next year to have a good music system outside the h/t room.

[TN Allen]

Thank you for doing this, I appreciate the clarity you provide, and plan to follow along and do the project. I have a little experience with Arduino and look forward to learning to do more using your project.

[neildavis]

I was doing ok till step 5. Krap, I was hoping to understand enough to use this.

Yep--article 5 is where it gets complicated, but it's just a draft. I need to point out that there are two ways to control the DSP. One is using C code in the Arduino, and that is what that article currently focuses on. The other is to use ASD, which is my version of the miniDSP GUI. ASD will hide all of that tedious microprocessor code. ASD uses that Arduino code, but the user doesn't need to understand any of that bit-banging going on under the hood--they just need to load the Arduino with the right code. So I need to point out that the microcontroller article is only applicable if you want to take control of the ADAU1701 yourself with a local user interface.

I'm at a resting point on the articles because I need to update ASD. I need to fix some things that got broken recently, and I need to get it to work with all Arduino boards. Right now it only works with Arduino boards that have the FTDI USB chip, and there aren't that many of them. And I don't want to write the next article on ASD until I've got the code updated.

Hmmm...maybe I'll split 5 into two articles: one if you plan to use ASD and the other for those determined geeks who want to write their own code.

[Kornbread]

I was doing ok till step 5. Krap, I was hoping to understand enough to use this.

[neildavis]

I've got drafts of the first 4 articles posted at www.audiodevelopers.com. I haven't gone back and edited, so there are probably lots of dumb errors and maybe some big ones. But it's a start.

[ernperkins]

Great start with the first article Neil. Rod Elliot isn't the only one convinced of the advantages of active crossovers; this is from SL's website: "Crossovers may be implemented either as passive RLC networks, as active filters with operational amplifier circuits or with DSP engines and software. The only excuse for passive crossovers is their low cost. Their behavior changes with the signal level dependent dynamics of the drivers. They block the power amplifier from taking maximum control over the voice coil motion. They are a waste of time, if accuracy of reproduction is the goal."

[Sydney]

... I don't think I'll ever be "done" with any of the articles--I always go back and rewrite things, especially if someone provides comments....

With that in mind in the book "The Design of Active Crossovers" By Douglas Self has some good reference material in chapter1: Crossover Basics on the advantages/disadvantages of Active Crossovers ( p 8 - 16 )

[jclin4]

I liked the intro article as well. It draws you in and makes you want to explore active speakers. I look forward to subsequent articles.

[neildavis]

The first article is fantastic Neil. Very informative and easy to read.

Will you post notices here in the thread when you complete articles on the site? I'm subscribing to this thread in hopes that you do so I can read the new stuff as soon as it comes out.

Thanks. I don't think I'll ever be "done" with any of the articles--I always go back and rewrite things, especially if someone provides comments. But I'll post when the first 4 or so are in readable shape (drafts). In the meantime, I'll keep working on the outlines and you can watch the articles unfold. I think I've got a useable first draft of article 1 posted, but the others are going to come more slowly.

Anyone should be able to add comments to the Wordpress page and I believe that anyone can subscribe to the RSS feed. I'll read up on RSS--I haven't used that feature before.

I'm not sure how useful these articles will be unless you have the DSP test bed to play with. I've got about 7 or 8 boards I can send out, but I want to finish off some of the software before making them available, as I get tired of apologizing for stuff that isn't working. And then I've got to get working on those case studies. It might take me a while to work through all of this.

[Kevin K.]

The first article is fantastic Neil. Very informative and easy to read.

Will you post notices here in the thread when you complete articles on the site? I'm subscribing to this thread in hopes that you do so I can read the new stuff as soon as it comes out.

[neildavis]

It's taken some effort to rework the Audiodevelopers.com website, but I finally got Wordpress installed and made a simple introductory page. I've got a start on the first article. I'll have an "official opening" when there is more content to share, but if you want to follow along and offer advice, please feel free to add comments.

Note: you might need to refresh your browser fairly often, because the content is changing quickly