[user18]

Quote:

Originally Posted by Jambo /img/forum/go_quote.gif 20 PCBs ordered yesterday I also have a tube of AD797s sitting beside a tube of WM8805s. I hope there's still plenty of interest in this as it is getting a bit expensive for me!!

I'm still interested. If you need a pre-deposit to offset some of your initial costs, let us know. I'm willing to pre-pay for a kit.

 

[error401]

Quote:

Originally Posted by Jambo /img/forum/go_quote.gif I just ordered the PCM2706s from Digikey, they're on back order and should ship on the 20th, I'm not sure if I trust that though. They're the only component that will be tricky to source that I haven't already got. I finished my degree this week so I've got plenty of time to spend on the manual and tidying up a few other things. I'm quite conscious of the fact that releasing 20 of these into the wild without adequate documentation could cause some real headaches!

Congrats!

I wouldn't count on getting those PCM2706, unfortunately. TI's site says they have 0 in stock and > 10,000 in progress, but not due until August. PCM2707 seems to be available though, so you might want to substitute, at least in the short term. I've had good success with DigiKey meeting the quoted dates on non-stocked TI parts in the past - provided TI has the parts in inventory. Ditto for ADI.

Packaging the little buggers has got to be one of the main reasons nobody seems to offer SMD kits. I just can't think of a labour efficient way to do it.

 

[BrianDonegan]

The PCM2707 (probably 2706) come in a tape package, much like smd caps and resistors. For those you could just cut up the tape.

For chips in a plastic rail, I just chop up the rail and use masking tape to cap the ends. Depending on the size of the rail, I use my bandsaw (not often) or a hot wire cutter. I picked one up for $2 at a craft store that runs on a couple D batteries.

For the R's and C's, just cut the tape and label them.

Of course, this is part of the reason I ended up pre-building modules.

 

[Jambo]

Brian - thanks for the advice. I had considered that but thought that perhaps the tape wouldn't give adequate ESD protection. I can only assume that you haven't had any problems.

Error401 - I'll see what happens on the 20th, if they don't ship then I'll change to the PCM2707. Chips are on their way to you btw

User18 - a great offer, thanks. I will probably take money between getting the boards and ordering the bulk of the parts for this reason - they'll all be on next day delivery anyway, but I think it would be foolish to take cash at this stage until I've checked that the new boards work.

 

[malldian]

Price point? I might have skimmed over it but I am interested in building something like this, and need to choose between alien or jambo

 

[Clutz]

This DAC should beat the pants off of the Alien DAC. If you can afford it, this is the way to go.

 

[holland]

Jambo, I'm interested. What is the final config (some parts went back and forth) you are putting together and the cost?

 

[CingKrab]

Just read this thread -- definitely put me down as interested as well.

 

[ziplock]

Mark me down. Looks good!

 

[Jambo]

Holland - I've just put together an updated block diagram which I hope answers all questions about the parts! USB receiver is undecided at the moment but will be PCM2707 or PCM2706, it is exactly the same chip (in this application) apart from that the PCM2707 doesn't allow control of the PC by simple switches that I have provided support for.

Other things that I either haven't pointed out before or have changed or may have been missed: Caps in the output filters are film caps - they're still 0805 SMDs though. The opamps are now in DIP packages rather than SOIC which allows for easy swapping especially when socketed (which they will be).

Now for the prices... In kit form, it will be £85 for the PCB and all parts (apart from power supply, switches and LEDs). Postage will be charged on top of this, but at no more than what it costs me. Apologies if this seems a lot, but it really has not been a cheap exercise to get this as far as it is!! Additionally, 20 is still low volume so parts/PCB discounts are not that great, and I've gone for domestically made PCBs this time as my last Malaysian ones weren't up to scratch. Not really price competitive with the Alien DAC I'm afraid but it couldn't be with these components!

Partially/fully built boards will be slightly more obviously, but I'm unsure how much more yet. I need to find out if I can solder SSOPs with lead-free solder and/or if I can legally post these out full of lead - I suspect that I shouldn't.

Listening to a bit of Ray Lamontagne through it right now, so clear!

 

[holland]

Thanks, that looks good. Did you switch to the torx142 or the totx142? If not, how hard is it to retrofit to handle 192Khz (possible external reclocker)? Cut the power trace, and lower voltage coming in, right?

I'm definitely in for 1 unless you're going to do another build with a reclocker inserted and pins to pull the differential signals out. If so, I'll wait for that one.

 

[rds]

That looks pretty sweet. I'll be ordering one soon.
Have you thought of doing a ps board?

 

[malldian]

Can you just purchase a board and give us a parts list?

 

[rds]

do you enjoy purchasing parts that much?

 

[00940]

Quote:

Originally Posted by rds /img/forum/go_quote.gif do you enjoy purchasing parts that much?

some people have plenty of leftover parts from other projects