Comments for my PCM2702 DAC layout? - Page 10

Tom: are you going to offer a kit?

I sort of doubt it in the near term. There's very little price break in volume for most of the parts. Plus, we've geared the boards and selected the BOM to be as cheap as possible - $2 and less than $25, respectively. I would probably have to sell at higher than that $25, which would ruin our biggest bragging point.

Beezar will carry, starting this weekend:

• the low-ESR gel cap,
• the Box Enclosure, and
• the shielded, full-rated USB pigtail cables.

That's mostly because many of Beezar's international customers have trouble with Mouser's international shipping costs (evidence Joneeboi's post). In the case of the Box Enclosure, they're not even available at Mouser or DigiKey. I'm also trying to carry the Pana FM power cap for similar reasons if DigiKey would ever get more stock. (Most US customers would order from Mouser, leaving out the excellent Pana FM cap.) They'll be overdue from Panasonic by 10 days tomorrow.

I'm not really anticipating carrying any of the SMD parts - for the time being. The PCM2702 is phasing out at Texas Instruments, but there are still hundreds in the inventory at Mouser (781 with >2000 in 10 days), DigiKey (919), and elsewhere. The TPS chips number in the thousands, perhaps tens of thousands counting various differing part numbers.

Any of this could change if I start getting feedback to the contrary, however. If international customers start having difficulty with the PCM or TPS's, it would make sense to just start carrying kits at that point. That's not that I'm pre-disposed in any way to international vs. domestic customers, but as indicated, US customers can do the whole thing for less than $25 by ordering from Mouser directly.

yeah, but beezar isn't on the wife's radar like Mouser is good to know though. I for one wouldn't want to stock kits with SMD parts either... I've had lots of problems with Panasonic parts in general from Digikey, so good luck there. They're discontinuing all the Panasonic 1% polypro film caps, which is sorta annoying. The replacement part is a 5% tolerance SMD part...

Didn't realize the PCM2702 was NRND . Wonder how they managed to get it to spec so much better than the rest of the series. Anyone actually measured real-world comparisons between the different chips?

I guess amb and MisterX's gamma1 project becomes even more relevant in the not-so-distant future.

Golly, I sure have to be careful what I post in this thread.

Au contraire! - cetoole will modify the Bantam layout to accept the PCM2704 or PCM2705 when supplies of the PCM2702 run thin. We've already been planning for that - but again, with almost 1000 at DigiKey and almost a similar number at Mouser, that's not going to be happening anytime soon. I would expect that to be a year or two, at least - especially since we and the Alien may be one of the few applications with TI claiming NRND.

If you look at the TI page on the PCM2702, TI is stating they have 2051 in stock as of today with ">10K" in progress.

Hi, As far as suppliers go in Australia a lot of parts would be a problem. Farnells carry a PCM2702EG4(Is this the same?) but only 1 of the 2 TPS's. As to the SMD parts could not find most of these in the correct values. Gave up looking at the rest after that.

I would have no problem paying a premium(preferably a small one) for a kit from Beezar. My last Mouser order cost $45 for shipping, my Beezar order for Max parts only $9.40 for shipping.

So if it was $2 for board, $25 for BOM and $10 for shipping thats still less than Mouser shipping alone!

Put me down for the first kit if you change your mind!

Hmm ... I'll keep it in mind. Maybe after the MiniMAX Case Group Buy is over and done with, I might be able to consider it.

Tom:

Do you feel that an isolator for the crystal is in order? I've always used them, but did it because there very first project I built with one speced one out, so I just did it by habit after that.

Colin will have to answer that one, I don't really know.

There were crystal spacers included on a single Alien DAC BOM early in the Alien thread, but as far as I can remember, there was never a single reference to them from anyone, nor were they used in any of the builds. I actually still have a set from my first Alien DAC order, but never used them and still haven't. My guess is that they're probably needed for portable use where shocks are common or on a big board with other crystals, but I doubt their usefulness on something like the BantamDAC.

Most likely he will see this, but I'll send him an e-mail, anyway.

My order from Beezar.com has arrived. I must say that those BantamDAC boards look reaally small !!

Regards

My new tools from Spark Fun Electronics came in Thursday and my Digikey order Friday, but I don't have any boards to work with. I have midterms two and three Mondays from now, so the next two weekends are out of the question for me. Maybe I could crunch out the build in a morning before leaving for school...

My parts arrived over the past week. What with travelling and my kid's birthday and work (of all things), I only got to solder it all up today.

tomb's instructions are just great and it all went together without a hitch. Sounds great, too! Thanks cetoole and tomb for making this astonishing and cheap gem available!

__Roy

I just finished another Bantam DAC, this time as a BantamCableDAC ( BantamCableDAC ). I'm sure it sounds great, but my wife snatched it immediately and I haven't had a chance to listen for more than 20 seconds after making sure music came out. I'm letting her break it in for me -- yeah, that's it.

It's a great and minimalist companion to my Mini^3 amp. I'll probably figure out a way to build them together into the same chassis one day...

In any event, if I can make two of these anyone can do it. The first one I made still sounds just great. As I posted earlier, I have DACs that cost 20X that do sound better, but man, not 20X better.

Two slight differences from the BantamCableDAC as shown on the project site:

* I used a 3.5 mm Neutrik stereo plug instead of RCAs, so I can more simply connect it to my Mini^3 amp

* I cut a U rather than a hole in each end of the beezar.com supplied plastic box, which made it much simpler to fit the whole thing together. About 1% less professional looking if you really stare at it, but fine by me. I'll probably add some zip ties for strain relief in a day or two, also because I didn't bother to bolt the board to the box (my local hardware store didn't have nylon bolts smaller than 6 this afternoon).

Thanks once again to cetoole and tomb for making this delightful little project available to the DIY community.

__Roy