[stellarelephant]

Wow these bits are tiny. At least I have a nice big blueprint!

 

[stellarelephant]

I have a wrist strap. I just noticed that the BOM calls for a 15k resistor for the LED and I bought 12k. Will this work ok?

Edit: I looked and I indeed have 15k, as that is included in the DK BOM. But I also have 12k that I believe I added myself because I thought you, X, recommended?

 

[xrk971]

12k or 15k can work just limits current through LED. 12k is brighter glow but 15k is visible enough.

 

[stellarelephant]

Thanks. Have to go to bed, but I think my first six resistors look alright. More tomorrow! Is it normal for my joints to have a little sharp point on them from where I lift up the iron when done?

 

[Lohb]

Just got all my parts today...by some great stroke of luck, FedEx delivered my Mouser and Digikey boxes simultaneously. Hope to have an amp together soon. I got some tiny .015 solder I think will work well. But I am slightly concerned that the 1.5 mm tip on my new iron is a bit bigger than Ideal size. Time will tell!

X, FYI it looks like you are somehow posting your replies within the quote boxes, which makes your reply harder to spot.

Will be looking out for your tweaked mousers parts results. I think you substituted out some parts for no low-end roll-off and better sweet-spot for 16 Ohms.
 
To the designer, mass produce these in a custom CNC'd case (bigger battery capacity space) , a bit lower on the price, and you'll own this price/niche. Well done !

 

[xrk971]

Not sure about lower price though

 

[stellarelephant]

X did you see my quick question about the appearance of my solder joints? I have my iron set to around 350c, though who knows how accurate the knob is. It is my first time using 63/37. I get a little point on the top of each joint when I pull the iron away.

 

[xrk971]

Are you using tin/lead solder? Your point is too small to transfer enough heat to melt solder and have it wet and make a meniscus. Maybe use bigger tip or increase heat. Should not leave a tip like that. Not just cosmetic but indicates solder is not really flowing like a thin less viscous liquid to wet underside of SMT part.

 

[stellarelephant]

BTW I think that a CNC case and big li-ion battery would raise the reasonable asking price, not lower it! It would be sweet to see though, that's for sure!

 

[stellarelephant]

Are you using tin/lead solder? Your point is too small to transfer enough heat to melt solder and have it wet and make a meniscus. Maybe use bigger tip or increase heat. Should not leave a tip like that. Not just cosmetic but indicates solder is not really flowing like a thin less viscous liquid to wet underside of SMT part.

I thought this might be the case, as I expected a smoother "bead" for each joint. Yes it's Kester 63/37 tin lead solder with rosin core. I'll crank the heat and see if that helps. Thanks.

 

[stellarelephant]

A bit more heat (looks like 375c) and a lot more practice, and my joints are looking better. All done with the SMT side!

 

[xrk971]

That looks good. You are halfway there. The through hole stuff is easy. Cutting holes in tin - if you don't have a paper hole punch is a pain.

Good luck!

 

[stellarelephant]

Getting close on the through hole side. Switched to bigger solder for this side so I don't have to feed a mile of the thin stuff for each joint. I'm working in spurts when my son is napping lol. Hopefully I'll get sound tonight after he's down for the count.

X, did you ever do a listening comparison with and without the WIMA output bypass caps? I think I'll try it. I am also planning to temporarily solder in some long wires so I can A/B different main output caps, by just attaching different caps with alligator clips. I have 3 to test...original 390uF Panasonic OSCON, 470uF Nichicon AK, and 1000uF OSCON. Should be fun to see if I can hear any differences.

 

[xrk971]

No I never compared without bypass Wima's. Wires with alligator clips is not best connection for sound quality. Maybe at least some header pin connector jacks for quick change.

 

[stellarelephant]

Its alive!  First impression listening to "Send it On" from Voodoo by D'Angelo: the bass is awesome!  Such ease...tons of power!  I'm feeding the Pocket Class A from the line out of my XDuoo X3, and it's driving my Sennheiser 598 cans quite loudly with the volume knob turned up probably less than a quarter of the way.
I can't wait to have a long listening session to get acquainted with the sound.  I haven't even soldered in the output caps yet, and this thing already rocks.
 

 
I've set up a quick and dirty way to compare the sound of different output caps using gator clips attached to wires temporarily soldered to the board...against X's cautions that it would sound crappy... So far I am just listening with 1000uF OSCONs, with no bypass yet, and I'm already pleased!

I have the original 390uF OSCONs plus some 470uF Nichicon AKs I will be comparing with the caps I have clipped in there now.  Any of these caps will fit in the tin.  I also have the 1uF WIMA film bypass caps, which I'm eager to try.
The contenders:


This is my first amp build and my first SMT soldering job...I took my time and it works perfectly.
Big thanks to xrk971 and BabyDontHertzMe.  I really appreciate all of your advice, X.
Now I'm going to go revel a bit.