Tuesday, January 19, 2010


Yeah, I know I should have been doing some work work today, even though the office was closed in observance of Martin Luther King Jr's birthday but instead I worked on a little project.

That DAC I blogged about the other day didn't come in a cabinet or case so I decided to put the two circuit boards and transformer into something I could keep in the audio rack. But what? Then I spied this nice cardboard accessory box that came with my blu ray player. It was such a nice box that I kept it, even though I had no use for it at the time.

Using some screws, washers, felt pads, a plastic food storage box from the 99 cent store and other odds and ends, I put all the pieces into one box. That was my project for the day. It actually looks pretty good, if I do say so myself. Here is a picture of it sitting on top of the blu ray player. The camera flash resulted in a not-so-flattering picture, as you can see. In indirect light when it is in the equipment rack, however, it looks just like the other black components sitting there and unless you look closely you can't tell it is a cardboard box.

Here's a picture of the innards.

After I finished putting it all together, I tested it out and it still worked, so I guess I hadn't accidentally severed any wires. And after doing more listening tests comparing this with what came with the CD player, I couldn't hear any difference. Someone suggested that it needs to have a break-in period, so that's what I will do - keep using it and see if the sound changes.

This was definitely more fun than doing work work today! (today being Monday)


donna said...

Good job! Very creative.

Anonymous said...

Very clean work. Looks pretty.

Electronics don't have bearing surfaces so don't expect a break in period.

Rickie Miyake said...

Thank you both.. it's about as good as I can do with a cardboard box, haha..

Now as for a break in period - there's very strong opinions going both ways but logically I don't see how something like that would sound any different after breaking in. I sure hope it does since I don't hear any difference now. One thing I really do not see are examples of when people compare something that is supposedly broken in versus something in new condition, side by side to see if there is a difference. Instead, they always talk about the same unit, how it sounds so much better after breaking in than it did when it was new - but how can you remember enough to do a valid comparison? I can't even remember anything from 2 minutes ago!

Anonymous said...

Interesting topic. I mentioned that I did sound reinforcement. Did I also mention that I taught A to D and D to A thirty years ago? I still have a ton of boards. In those days they were thermometer and then microprocessor controlled oversampling. Very slow microprocessors. Z80's at 2.8 Mhz and we programed the code. I moved on to direct applications of pulse width modulation in the early '90's. It looks like your D to A is PWM. Too cool. Very cutting edge for audio. Knowing you, you bought a very fine MASH or high end oversampling unit and will not hear a difference in a PWM D to A.

Break in? Infant mortality is what I experience. Which is again a very topical discussion. I went to the post office to return a flashlight that smoked on me today. I think its PWM D to A driver circuit fried. Yes, they have them too. So here's the deal. I gave my son a Surefire flashlight. It has a PWM D to A driver to ramp up the voltage to its lamp. Its the Aviator A2 with three green LED's for low light applications. It's rated at 55 lumens and cost $199 plus tax. Its not bad for the size as it fits in a pocket and a double D Maglight puts out 37 lumens. So what I returned was the Ninja knock off. Its PWM and uses the Cree R5 LED. Same size as the A2 but puts out 330 lumens. It uses its microprocessor to control its D to A converter to signal SOS and go low power. It was $22 delivered to the door. Unfortunately as I was ramping up the voltage, it died. But while it was going, man was it bright.

Rickie Miyake said...

What is "PWM?"

Anonymous said...

PWM is Pulse Width Modulation. Basic concept of how switching power supplies work in computers. That's how they are so darn cheap and light. In my world of programmable controllers a power supply putting out 450 watts at 5 volts goes for over a grand. Its just a transformer, regulator, and filters. A computer power supply will put out the same using PWM for thirty bucks delivered to your door.

BTW, on the same day the flashlight was delivered I received a laser I bought for the boy's .40 Sig Sauer P226. Even though it has tritium sights having a maximum legal power green laser is very cool. The one I received was low powered and red. When I complained, I was told to post my observation on the website and ask for advice how how to fix it. So I posted up both their response and my question. How do you change a weak red laser into a green laser?