. . .Oh, and can't forget Schmartboard, without which it might be almost impossible to use a lot of the small surface mount IC packages such as the TSSOP for the WM8524 DACs or TQFP for the ADAU1442 audio processor.
X2Dude, that's badass! Congrats!
Can we get screenshots?
x2 I don't know a whole lot but, I can tell you that I've been reading all the posts about processors for the past few days and rarely are people satisfied. Well, except those that use 1 or more Mini DSPs. Nice looking work, 24th.We're in need of more processor options.
I am VERY intrigued by this (not to build, but certainly to buy)
Initially I did not intend to build this box for sale. Nonetheless I looked into it. But alas the answer is no, because without the flexibility afforded by software, the box doesn't seem very useful, and according to Analog Devices, their software is not licensed for use outside of design. (And I have no intention of learning how to write software to use the box; moreover I think a major strength of the box is the SigmaStudio software it uses -- I wouldn't want to change that!) A thread about ADI's software licensing is here. (And perhaps of interest, in the thread they mention programmable car audio amps that use their SigmaDSP products (like a miniDSP embedded in an amp); here's the link).Building to sell or just personal use?
One of the main things miniDSP provides is software that allows us to use the ADAU1701. But IMO their software takes away from the full potential of the IC. Nothing against miniDSP, it's just a necessary trade-off. Actually, their prices seem very competitive, and they bring value in that their device does not require assembly. Furthermore they appear to offer easy-to-use software for operating the IC. A good product IMO.I can tell you that I've been reading all the posts about processors for the past few days and rarely are people satisfied. Well, except those that use 1 or more Mini DSPs
Can we get screenshots?
I'll provide a screenshot, but it doesn't do much justice. To see just the "tip of the iceberg" of what this stuff can do, check out these two ADI videos with the girl in the pink shirt here.Got any screen shots of the interface
It gets warm but not hot. I chose linear IC voltage regulators, so with the car at 13.3-14.4 V and the ADAU1442 core running at 1.8V, there is over 10V to burn at ~300 mA -- not including other components. I just stuffed some resistors in there so the regulators wouldn't get too hot. Heat was a concern initially but it hasn't become an issue. Nevertheless, just in case there were heat problems I had a switching power supply available: a 8-42V DC input, 3.3 or 5V DC output breakout by Sparkfun. (The breakout was cheaper than I could get the part (LMZ14203) when I bought it).Does it get warm? Looks kinda cramped in there?
Good question for a DIY setting. I'm glad the question was asked because I ended up learning something. But first, a components "recipe" with costs:What was the total cost of the parts if you don't mind me asking.
Elegant yes, but credit Analog Devices. All I did was solder some IC's. For $699 a person could buy the evaluation board for the ADAU1442 (several years ago I received something comparable for the ADAU1701 for free; it's in the pic above). No assembly required and a lot of powerful software right out of the box -- and no DSP assembly programming needed.I stayed away from this option due to a severe lack of knowledge on coding DSPs. It looks like you have created a very elegant solution to a problem experienced by many.
Actually, when I first started using SigmaDSP ICs and SigmaStudio software (with an ADAU1701), I emailed Sir Siegfried to tell him about it. In addition to active crossovers for speakers, I think the real-time control capability would have been of interest to him; for example, it could be used to conveniently A/B test whether a person can hear distortions due to phase such as is discussed in his Group Delay and Transient Response section (see especially the last two plots in section F). He was polite and emailed me back, which I thought was nice, but he didn't seem overly interested in what the ADAU1701 and SigmStudio has to offer. An oversight by him IMO -- but I should say that his site is hands down, far and away, the best audio resource I've ever encountered on the internet.looks like the evolutionary step for the Linkwitz Pluto's analog filtering replacement
I'd be happy to charge a lot of money, but I made neither schematics nor even drawings for this project. The reason is that they're all already available online for free. Just about everything you would need to know is in the links in the bullet points of the "components recipe" I posted above. Take the ADAU1442 for example. The link to its data sheet (a PDF file) is here. Look at figure 64 on page 89, "Self-Boot Application Schematic". The ADAU1442 should work if wired as shown in that figure, except for two misprints that I'm aware of: (1) supposedly, there should be a 10k resistor between pin 21 (CLATCH) and ground (I haven't tried it without); and (2) on the "self-boot switch" at the bottom of the page, "DVDD" should actually read "IOVDD". If a person were unsure of whether I'm right, you could go straight to the source and post in the help section for SigmaDSP's in Analog Devices' help forum here. Now, suppose you didn't know what that three-lead symbol is next to "REGULATOR" in the schematic. Searching "regulator" in the PDF would lead to a nice explanation on page 25: Analog recommends the NJT4030P from ON semiconductor. Google NJT4030P and so on. This, along with looking at the evaluation board schematics for various ICs, has basically been my approach, and after googling a few things I didn't understand, it all ended up working. Another good resource if a person got stumped by something would probably be diyAudio. I don't really go there but I think they build a lot of IC's and would be happy to help. (Relatedly, they might be interested in a build such as this but I posted here b/c I use it for car audio).If I order a ADAU1442, and get a software key, how much would you charge for plans to build my own?