The 4 inputcaps are the blue electrolytic capacitors, signal is bypassed by 0.1uF red Wima's. Heatsink prevents them to be closer to chippins
Am I right in thinking the board is in master mode by default? Just making sure before I solder the gain setting resistors and I don't want to get them the wrong way round.
Single chip boards should be master. On (most/all???) PCB's left side resistor (if chip is behind resitors when looking) is R2 from datasheet table, right side R1. Removing left side resistor R2 will make chip startup in 20dB master. Chip won't produce output without R1 from datasheet table, I made that error, it didn't destroy chip🙂
Would you suggest a mod to remove the input Caps and place them on the underside of the pcb to be closer to the chip?
Guys, I just had time to install the bootstrap snubber circuit and it works! Makes a huge difference in sound quality: the sibiliance on some tracks is now gone, and the test I had was a certain passage in a CD (Chopin Piano Sonata No. 2 in B-flat Opus 35) that gave me problems before. It is in a complex piano passage where many notes combine and are struck with force. Normally, the confluence of all those notes go to mush - almost like the speaker hit its mechanical stop. With the bootstrap snubber in place, I can actually hear that note now undistorted.
I am using 330pF 100V ceramics from AVX and a 1/4-watt 10 ohm thin-film resistor. I scraped off some of the varnish from the back of the YJ blue/black for ground pads and soldered the cap-resisor combo point to point from the bootstrap pin sticking through the bottom. This is a very easy and worthwhile mod. I can't believe the regular TI schematic did not include this - it is so cheap and easy yet yields big improvements.
I also think that this mod reduces the warming of the cheap stock 10uH inductors - maybe less hash for them to filter out?
I agree, this looks quick and easy, but I'm curious why you scraped off the PCB coating to get access to the ground plane? Why not connect all the ground ends of your RC snubber circuit via a wire (or to each other if they'll reach), and then ground them to the GND of the DC input (which pokes down through the PCB)? I know we generally want to keep leads short as possible, but does it matter on something like this that's just going to ground?
I don't have the caps for this, so I'd order them, and go with axial if they're available. Judging by your picture, with a little planning, I think I could make all the ground-ends come together on a common point (like a star), and then either only scrape away one spot on the PCB, or just run a wire to the DC GND.
I wouldn't. TI themself puts Rch inputcaps at equal distance as this yellow board, Lch inputcaps at double or triple this distance. There could be a little difference in sound and distortion when replacing the input-electrolytics for other capacitors, but can't really say from picture how amp sounds.
Yes, in this case you want them as short as possible even though they go to ground. The reason is that they are connected to the high freq RF modulated output of the amp and are acting as antenna radiators until they reach ground. I scraped off 4 spots to solder because it was faster and easier that way because I did not have to mess with a star or ground bus which are more wires and potential for wires to get crossed with exposed pins on bottom. Plus I wanted to keep it short.
I applied the 330pf+10R mod xrk871 suggested using available parts (Wima MKS330pf 1000V), the improvement is great, almost all the hrash sound had gone, I listened for 3 hours tonight and continue tomorrow evening. I also feel that the mids are more clean. Great mod and thank!
I was also thinking would silver mica be better choice for those 4 caps since I can get them for 2US$ each.
I was also thinking would silver mica be better choice for those 4 caps since I can get them for 2US$ each.
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Awesome to hear that I wasn't just imagining the improvement! 🙂
😎
I don't know if mica caps would be better? $2ea is kind of pricey as the 330pF 100V AVX are $0.31 ea and seem to work well plus they are tiny and you can squeeze them in almost anywhere. Invalid Request
I can only get my hand on few 330pf Wima and they are about the size of those 0.1uf Blue film cap on the board, as for resistor goes, only got the 1/4W, 1/8 would be smaller. The soldering isn't look very nice, just to try it out quick.
Skylab,
I guess you have wirewound resisitors? The ones I ordered are 1/4 watt metal film and they surprised me by how tiny they are. Here is link in case anyone is interested.
Invalid Request $0.14 ea.
For those still wondering if they should try this mod: just do it and you won't be disappointed. Easy, cheap, fast. I found myself really liking the sound of the amp which I thought sounded quite good to start with. It just made it even better and music was very enjoyable, especially complex pieces with lots of dynamic content like piano, and female voices became more fluid and clear.
I guess you have wirewound resisitors? The ones I ordered are 1/4 watt metal film and they surprised me by how tiny they are. Here is link in case anyone is interested.
Invalid Request $0.14 ea.
For those still wondering if they should try this mod: just do it and you won't be disappointed. Easy, cheap, fast. I found myself really liking the sound of the amp which I thought sounded quite good to start with. It just made it even better and music was very enjoyable, especially complex pieces with lots of dynamic content like piano, and female voices became more fluid and clear.
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That's a tiny one that you shown, actually I can get some SMT 10R with smt 330pf this weekend and try again. I also want to try the mica...This is a easy mod that at least I won't break the trace.
Which TPA3116 board to get?
Hey guys,
Can somebody give me a link to the best TPA3116 board
Figured you guys have reached a consensus to the best so far?
Scott
Hey guys,
Can somebody give me a link to the best TPA3116 board
Figured you guys have reached a consensus to the best so far?
Scott
Good question 🙂
I don't know - I've only tried the Audiobah one (and the Sure TPA3110D2).
I would like to know if anyone has found anything that betters the TI evaluation board.
I don't know - I've only tried the Audiobah one (and the Sure TPA3110D2).
I would like to know if anyone has found anything that betters the TI evaluation board.
I bought the audiobah but haven't tried it yet.
audiobah ebay link
Took about 3 weeks to get it from China to LA.
Sorry, not too crazy, that was even quick. I was waiting two weeks alone to be dispatched after placing the order and another two for delivery. That place is the only one and exclusive for this kind of board, so they certainly have many orders and clients to satisfy 😉