I was given the advice that the CS4397 might suit my needs for PC audio. That is, very detailed, good soundstage (use the PC mainly for gaming and hearing what’s going on around me helps alot) and a tiny bit on the bright side as my Philips Fidelio X2’s are just a tad on the warm side.
I etched the board today and it is the best etch I’ve gotten to date using the toner transfer method.
I will use an USB to I²S board based on the XU208 and using Sitime oscillators. This board is on it’s way to me to be reviewed.
For PSU I was thinking of either the TPS7A4700 or the LT1963A. One regulator for digital supply and one for analog supply.
The output from the DAC will be a transformer based one using a pair of Edcor WSM 600:2K4 (IIRC), the transformers and the DAC IC is being gifted to me by my dear friend David from Minnesota. Thanks my friend!
Is the reason for this blogg not being updated as much as I would like. It’s also the reason for some projects not being done that could be done as I have all the parts.
Even with strong painkillers, I have rather severe pain all day every day. I am waiting on an appointment to get my back from the neck down looked at in an MRI.
For now, I take care of my daughter first, and if there’s any energy left in me, I do DIY.
Yesterday I got the PCM1794 expansion boards for the main-/expansion board DAC project.
4-layer boards that came out quite nice. As the last time I used elecrow, I got twice the number of boards expected.
It’s time to put together another order from mouser. I only send an order off when I have reached the free shipping limit. If I didn’t do that, shipping cost would be half the order total.
I do order small quantities from time to time from micro-kit (great to get Elfa disrelec and Farnell stock at one place) or electrokit.
Mouser was the only source I found for the large size SMD resistor nets I used on the DAC mainboard.
I got some Vishay thin-film .1% resistors for the same board (these are for the LT1963’s and the LT3042IMSE).
As luck would have it, they (mouser) also had the big size SMD oscillator, 22.5792Mhz I still needed to source for the Audio-widget/FreeDSP classic SMD.
Funny thing about that board (Audio-widget/FreeDSP board), it’s the first time I’ve got all parts, but in too small sizes.
I mainly use SMD’s to keep boardspace down, so I mainly use 0805’s with the occasional 0603, 0402 and sometimes 1206 resistors for the extra power handling.
If a TH part lets me do a better layout/smaller board, I’ll use it so I’m not biased one way or the other.
Anyway, I noticed that mouser has lifted the free shipping limit from 40eur to 50eur since I last ordered from them.
These arrived today 🙂
For more info look on the DAC/Mainboard-page.
Pics(bad cellphone pics I’m afraid).
These I had made at elecrow, soon after having ordered these and the 4-layer PCM1794 expansion boards, I noticed the “Premium PCB Service”. It’s only $1, if it’s for the lot or per board I don’t know.
It is a visual inspection of the boards in addition to the electrical test. It also allows for thicker copper, thinner traces, smaller vias etc.
The board has gotten some more parts populated.
There are still some parts that I don’t have in the right size or of good enough quality. For capacitors I use C0G/NP0 or PPS where possible and X7R where there’s not enough room for better capacitors.
Resistors are ordinary 1% metalfilm.
Some of the values are yet to be derived from audio-widget and FreeDSP classic schematics.