DIY DAC with mostly through hole components?

gamma1

With work, you could probably build and design something totally through hole, but it would be work. There are through-hole DAC chips out there.

After soldering a gamma1 today I can understand the quest for DAC without SMD, I didn't really enjoy it (although made my appreciate the through-hole stuff alot more :P). And next time there is SMD involved I'll definitely be tempted to outsource it!

I've finally gotten ok at SMD soldering, but what are these through-hole DAC chips? I'd be interested in messing with one.

PCM56
AD1865
AD1866 (HeadWize - Project: A Portable DAC with Headphone Amplifier by Andrija Ifkovic although still some SMD for the receiver)

not common today so you have large minimum to order just to get some.

Once you get the hang of placing SMD R & C, I find it goes much quicker than through hole (as you are not constantly turning over the board).

I personally like SMD soldering too.

Heck, through hole is too much work.

WAIT, I'll buy a hot air station and get those done in minutes without me doing it.

SMD does get a good bit easier. Look at the SMD on the gamma2, those chips have seriously small pitch. Trick that makes that easier is to use lots of flux and not worry about creating bridges and just go back and use solder wick to clear the bridges. Makes for quick and easy work of it. However if you are good with using lots of flux and get the swipe technique down it is pretty easy. My hardest part with SMD is the first joint and lining every thing up.

For SMD, do yourself a favor and buy a syringe of solder paste. A dab on each pad, place the part and heat. You can do the whole board at once on a hot plate, or even melt the paste with your soldering iron tip if you want.

Electronic Grade Solder Paste > Main Section > Stan Rubinstein Assoc., Inc.

It's not even expensive. Remember to get a tip for the syringe. I use the NoClean 63/37.

(I have no ties to the above company, but I do buy paste from them)

SMD DOES get much easier with practice. I started out like many of you: "rough" soldering followed by de-solder braid ("spiked" with a bit of extra flux) to eliminate bridges. With a little practice, I found it easier and easier to accurately solder the larger stuff (passives,discrete transistors, and SOIC) without bridges. I've not been able to do this with most QFP devices thus far due to the fine pitch.

Solder formulation is also important here. It's much, MUCH harder to use SAC or other Pb-free formulations than good ole' 63/37. My favorite is Kester #44 0.025 63/37; Radio Shack sells 62/36/2 in both 0.015 and 0.022 (probably made by AIM or Kester) and is of noticably higher quality than the other solder formulations they carry (plus the Ag content makes solder joints REALLY pretty!)

Lots of people swear by solder paste followed by "baking"/hot-plates (as suggested above), but I've not tried that technique yet.

The biggest drawback of SMD that I've encountered is in breadboarding. (I don't care how good simulation software gets, I'll always breadboard because it's a lot more fun!)

I think now is the time for hobbyists to warm up to SMD because it is only going to get more prevalent. There WILL be companies making through-hole stuff long into the future, but it will mainly be for purposes of repairing old equipment. It won't be long until commercially-made equipment uses exclusively SMD parts (lots of stuff is already) except perhaps in the power supply or for high-power applications.

Perhaps this?

Silicon Chip DAC Kit

DIYAudio Thread on the DAC

The DAC chip is PCM1796. This and the DIR9001 SMD chips come pre-soldered according to the people I know who have bought.

It promises good performance, but also a lot of scope to modify and have a good play.

I'll probably buy one in the New Year to play with, although I'm not expecting it to better my Buffalo32!

Something to look forward too!

Thanks for the tips and hopefully it does get a bit easier this time.

Might even try hot-plating.

I've used a old pot and the stove to do the hotplate technique. Worked out very well for a single sided board. Just don't use the pot to cook in afterwards (and you want a fan that vents to the outside running while you do it).

How sensitive are the Gamma1's parts to heat? How well and how do I need to sink the ICs when working on them?

I'm deciding between building the Gamma1 (cheaper, SMD) or a CK2III/M3 (more expensive, less SMD) first. No soldering experience... but in the words of Clarksonius, how hard can it be (given that I've read a couple guides on general soldering, and I've watched the video linked on the AMB website about SMD work)?

That's not really needed. The fumes are no different than normal soldering fumes.

If you consider that if you are doing it on the stove, you are in an area where you normally cook (which is not the place I normally do my soldering) I want venting. As well, the fumes from the paste that I have seemed more intense than the fumes from wire solder.