[Folsom]

swapped both sets of caps with no problem. but i just realized i dont know which components are the inductors. are those the little blue rectangular components immediately in front of the chip heatsink, or the square black components immediately after?

small blue components are through hole, square black components are not.

Blacksquares. There's not much room there, I'm curious how people have been removing them. I'm sure some have tweezer solder irons.

[thaddeussmith]

gotcha. i do not have a tweezer soldering iron, so I may just have to skip them for now.

here's a pic for size reference.

[Folsom]

Maybe it's risky, but they might pull off with ease. I'd be afraid to lift the tracks, but looking at them it's possible they slip onto some tabs.

I'm really not sure, as I've only as recently as you got into amps with output inductors as such.

[thaddeussmith]

well, shit. i tried to pry up with a flat screw driver with just the slightest pressure and it ripped right off, along with the trace. so I've got a dead board. 

[rhing]

Nice work there with the new Wima input caps and Elna Silmic IIs. Why don't you give the modding a rest and try the new components that are in there now? The Wima's and Silmics will take at least 20 hours to really burn in and open up. At least you'll be able to hear what has improved or gotten worse.

You started on this before I could post, but for future reference, here you go...

For removing the black shielded inductors, they are soldered to pads fore and aft. To remove them cleanly without lifting the pads, it will probably require two people. Have one person hold a soldering iron with a fine pencil tip to one pad while you simultaneously heat the other pad and gently live the inductor off the pads. You can only see a sliver of each pad under the inductors, so you really need steady hands and patience here. I would recommend asking a very patient friend to help you out.

You might be able to salvage the board. Just try to identify where the Copper traces lead to the pads and carefully and gently use an X-Acto hobby knife with a sharp blade to scrape off the top layer of resin. If you do this correctly, you can glue the pads back on the board with Super Glue or Crazy Glue, and solder in small pieces of wire to bridge from the exposed traces to the repaired pads.

[thaddeussmith]

ya. too late

back to YJ I go (unless there's a way to salvage the trace?)... the caps can be reused.

[rhing]

Try the repair method first. I speak from personal experience.

[Folsom]

You can follow the trace and just replace it with wire. (perhaps, depends where it goes, maybe scrape down to the trace to create a new pad if it leads to the chip? I dunno what the PCB is like to dig into on these boards, some is easy, some is RESILIENT)

Too bad they're that hard to get off. When I have to deal with some components I don't like, I just cut them into pieces with some sharp dikes. For example the tiny blue pots that come on the YJ red boards, I just cut em up a little till I've got 6 easy to remove legs! Actually I prefer to use a desolder tool but I need to order another one.

[thaddeussmith]

it looks ghetto, but i was able to scrape enough trace to take the solder and hot glue to hold it all in place since the traces were peeled away from the board. is this going to be like driving with 3 flat tires and one good tire by having the single bourns inductor?

i at least have clear sound out of both channels. will go through my test playlist later this evening.

[wushuliu]

You can follow the trace and just replace it with wire. (perhaps, depends where it goes, maybe scrape down to the trace to create a new pad if it leads to the chip? I dunno what the PCB is like to dig into on these boards, some is easy, some is RESILIENT)

Too bad they're that hard to get off. When I have to deal with some components I don't like, I just cut them into pieces with some sharp dikes. For example the tiny blue pots that come on the YJ red boards, I just cut em up a little till I've got 6 easy to remove legs! Actually I prefer to use a desolder tool but I need to order another one.

The inductors should come off easily with a solder iron as rhing mentioned, the tricky part for me is not melting any of the filter caps near them, so might have to remove them beforehand then reinstall. Also a chisel tip for the iron will be help a lot.

[thaddeussmith]

Well I'm up and playing, even with the gimpy looking inductor. Seems a little punchier throughout the range. Nice clear mods and highs, good solid bass. Good depth of field in the sound stage. Seems a little less noisy. I took the capacitor off of the power inputs, not sure if I'll put it back or not yet.

Doesn't seem to have any adverse effects with the single bourns inductor in place, but now it's one of those things that I know is there and is likely going to trigger my OCD on a regular basis. Not sure I want to risk trying to replace the other 3.

Tonight, I just listen.

[thaddeussmith]

I lied. Whether placebo or real, after a while the right channel with mismatched inductors just didn't sound right. The music seemed off, like milk that was on the edge of being drinkable.

So I went back at it with cautious hands and a more delicate pry tool, carefully applying the soldering iron tip to each pad and gently prying up from a non-contact side. Out of the next 3 inductors I only messed up one pad and was able to scrape away enough of the trace to make a pad. They all fit on the board without the need for any real bending of the leads, and I applied copious amounts of hot glue to both insulate the leads and provide support.

Whether placebo or real, it sounds like I was expecting it to.

[lacro]

Fired up my new YJ 3116 (stock) board to see if it works and doesn't produce smoke I am powering it with my 12V lawnmower battery. When I first turned it on, it sounded bad compared to my modded 3110 boards. However, after about 5 minutes everything started to smooth out, and it's been playing about an hour now, and keeps getting better and cleaner sounding. Can't yet say it sounds better than my 3110's. It's driving my X-LS Encores easily.

 It takes 3 solid weeks to get this board from China, so I am a little nervous about making changes so maybe I will leave this one stock and order another for modding.

[rhing]

It takes 3 solid weeks to get this board from China, so I am a little nervous about making changes so maybe I will leave this one stock and order another for modding.

I hope this was the YJ blue amp that you painfully waited for. Although, I can't knock the YJ red amp since I never tried it. I really like the YJ blue amp and I've been reluctant to do a lot of mods as it sounds great as I have it now (pair of Panasonic FM 1,500uF / 25V as DC decoupling caps, and my homespun shielded internal cabling). That said, my little TPA3110 amp is no slouch. Going old school right now and jamming to Supertramp's "Crime of the Century" on my turntable with my tube phono stage and linestage preamps driving the diminutive TPA3110 in a little black box. Sounds fantastic!

[Captainhemo]

Fired up my new YJ 3116 (stock) board to see if it works and doesn't produce smoke I am powering it with my 12V lawnmower battery.

Doesn't the 3116 like a bit more power  than 12 V ? 
I'm considering orering one of these from  YJ (blue board) myself.... is that  24V/5A SMPS YJ sells  worth picking up to start out with ?

-jay

[lacro]

I hope this was the YJ blue amp that you painfully waited for. Although, I can't knock the YJ red amp since I never tried it. I really like the YJ blue amp and I've been reluctant to do a lot of mods as it sounds great as I have it now (pair of Panasonic FM 1,500uF / 25V as DC decoupling caps, and my homespun shielded internal cabling). That said, my little TPA3110 amp is no slouch. Going old school right now and jamming to Supertramp's "Crime of the Century" on my turntable with my tube phono stage and linestage preamps driving the diminutive TPA3110 in a little black box. Sounds fantastic!

Yes... it's the blue board. I think I might get a C&C tube preamp to put in front of it. Any particular reason you used the Panasonic caps, and did they make any difference over the stock ones?

[rhing]

I used the Panasonic FM caps, because that's what I already had on hand. They're good for these applications, and to my ears, the sound is clearer with better dynamic response. I like Elna Silmic II caps too, but I just didn't have them.

[lacro]

Doesn't the 3116 like a bit more power  than 12 V ? 
I'm considering orering one of these from  YJ (blue board) myself.... is that  24V/5A SMPS YJ sells  worth picking up to start out with ?

-jay

Hi Jay,
 Nice to see your interested in these little wonders. Be careful their addicting and a whole lot of fun for cheap. To me they are a great learning tool for modding. I bet you will be surprised how good they sound with your speakers, and your nieces Encores.
 Check post #288 about PS voltage. I had the same question as you about powering with 12V instead of YJ's suggested 24V PS.
 Your a lot closer to Hong Kong than I, so maybe you wont have to wait 3 weeks

[Captainhemo]

Hi Jay,
 Nice to see your interested in these little wonders. Be careful their addicting and a whole lot of fun for cheap. To me they are a great learning tool for modding. I bet you will be surprised how good they sound with your speakers, and your nieces Encores.
 Check post #288 about PS voltage. I had the same question as you about powering with 12V instead of YJ's suggested 24V PS.
 Your a lot closer to Hong Kong than I, so maybe you wont have to wait 3 weeks

Thanks Larry, I must have missed  that when I was  reading through the  thread.
It is pretty tough not to take an interest in these little guys .   If I do pick one up, I'm planning to use the GF TD 11 as a preamp.  Kind of anxious to see how the amp would pair up with the OB7's..
Usually  when I've ordered stuff from  China in the past,  it's typically 1  week  for delivery.

If I pick one up,  Ill keep yo updsted on  how it works with the OB7's

-jay

[rhing]

Yuan Jing recently introduced a complete amplifier based on their acclaimed TPA3116D2 blue amp module. This is complete with a black Aluminum case, volume pot and power supply for $88.

http://www.yuan-jing.com/tpa3116-class-d-2-0-stereo-power-amplifier-50w-50w

For those who are not comfortable slinging solder or experimenting with potentially hazardous power supplies, this amp is calling your name. In assembling a BOM with comparable parts from Mouser and Digikey including an enclosure, my total was about $100 and this does not even include a power supply.

If you want to DIY, this is still a good foundation to start with and swap in your own caps, volume pot , inductors, etc. What's funny is that an audio buddy and I were wondering when Yuan Jing was going to come out with a serious audiophile amp bearing the blue amp module. Here it is. Don't waste your time with the Yuan Jing 2.1 amp with those cheap tone controls. The blue amp is the one to get.