a quality heat gun with fine tip attachment, or a heat pad used for reballing would probably work fine.
https://www.youtube.com/watch?v=0XENpPtisnM
I put a few caps on my 3116 builds. I think it improved sound a bit, better bass, better range on loud passages, perhaps smooths out the laptop power supply bricks providing power.
add the caps in parallel to the power inputs of the boards.
I used 2-4 1000uF caps for mine.
Some people go really crazy on this and add tons of caps, but then you have to worry about power supply shut down and such on the in-rush of current.
here's a photo of one of my builds.
This board is for the power caps I added--2x 1500uF, and the resistors that power the LED power indicator light...
https://www.flickr.com/photos/45066974@N08/14989258944/in/dateposted/
add the caps in parallel to the power inputs of the boards.
I used 2-4 1000uF caps for mine.
Some people go really crazy on this and add tons of caps, but then you have to worry about power supply shut down and such on the in-rush of current.
here's a photo of one of my builds.
This board is for the power caps I added--2x 1500uF, and the resistors that power the LED power indicator light...
https://www.flickr.com/photos/45066974@N08/14989258944/in/dateposted/
Last edited:
the problem I have with many 'mods' is that diyers often think they know better than the chip designers. and if the chip designers worked out what the reserve cap needs are and ref boards are made, its not very common that they got it very wrong.
"'add more caps!" is a cry that feels like nails on a chalkboard, to me. in some cases, it makes some sense, but more often than not, its just someone who had read just enough to hear of some concepts but not enough to know if it applies to this or that tech.
switching amps and switching psus are DIFFERENT ANIMALS from class A and AB amps and psu's.
my gut feeling is that if you give enough of a current (4A or so) from a local switching PSU, 'storage bank' caps are useless in this config. in fact, they are likely to be counterproductive since the switching psu should react fast and the board certainly will react fast - that's one of the benefits of a high-mhz style switching system.
if the psu can't handle surge power, then blame the psu. don't go adding 'bulk caps' as a band aid. do it with with a properly spec'd psu and ignore the urban legends of 'moar caps!' (lol) being the goto solution for diy 'mods'.
"'add more caps!" is a cry that feels like nails on a chalkboard, to me. in some cases, it makes some sense, but more often than not, its just someone who had read just enough to hear of some concepts but not enough to know if it applies to this or that tech.
switching amps and switching psus are DIFFERENT ANIMALS from class A and AB amps and psu's.
my gut feeling is that if you give enough of a current (4A or so) from a local switching PSU, 'storage bank' caps are useless in this config. in fact, they are likely to be counterproductive since the switching psu should react fast and the board certainly will react fast - that's one of the benefits of a high-mhz style switching system.
if the psu can't handle surge power, then blame the psu. don't go adding 'bulk caps' as a band aid. do it with with a properly spec'd psu and ignore the urban legends of 'moar caps!' (lol) being the goto solution for diy 'mods'.
There is a rather wacky optical illusion in your photo. Making it appear that power connections are wired to the audio input on the left amp.
Yup. I looked at it multiple times before posting anything, and then again after. I'd meant to follow-up and posted that I finally figured out what actually happening. I am no longer concerned
For each board, I'd try one of those caps (in the correct polarity, and assuming they are rated to at least 25v) between the power inputs, as close to the board as possible. That might help a little with power at the low end, but really, a suitably sized PSU is probably the first and most effective measure to take in that regard. At least that's my understanding.
Page 99
Have been reading this whole thread to dust up mods. Found this the most interesting. Im actually very happy with the sound of the boards from stock. Except gain which I changed. But I also have this high pitch sound when nothing is playing. Barely audible, but I know its there. Which mod is the most likely to fix this? By the way. Couls I leave the stock SMD caps and put one big ekstra on power input instead?
Regarding mods: Judging from that photo, I'd say that if you aren't unhappy running a heavily modded board on one channel, and a nearly stock board (other than gain) on the other, then you are well past the point of diminishing returns on any mods.
Regarding the noise. What do you have connected to the inputs? Does what you have connected effect the noise? What happens if you put a low-value resistor across the input (for diagnostic purposes only)?
Hi guys,
I want to build two slim mono-blocks using the sanwu boards and 2x MeanWell LRS-75 smps. I am a little concerned about the temperature inside the case so was thinking of adding a small fan to move air through the case.
Aside from adding in a ac/dc step down convertor, is there any other way to wire in a fan?
Cheers
I want to build two slim mono-blocks using the sanwu boards and 2x MeanWell LRS-75 smps. I am a little concerned about the temperature inside the case so was thinking of adding a small fan to move air through the case.
Aside from adding in a ac/dc step down convertor, is there any other way to wire in a fan?
Cheers
It seems to me that this 'problem' is an imagined one. The chip designers design to various technical goals, but not sound quality as that does not feature in the datasheet. DIYers in general are after the most pleasing sound.
The assumption here is that 'wrong' is related to the measurements and I'd agree they don't commonly get it wrong in terms of meeting the measurement specs. Pointing out that more caps sound better is far from saying the chip designers 'got it wrong' in terms of the numbers.
So are you saying here that DIYers describing the SQ results of adding caps are merely propagating 'urban legends' ?
its a bit OT, but what I am saying is that the thought of 'more caps' often is just a thing people will jump to and I remember seeing it in car audio and shaking my head back then, too.
a circuit will have enough localized storage and bypass caps to do the job. to 'append' (lol) extra baggage to well designed boards is the thing I kind of object to. if the design was crap, ok, fine, mod the hell out of it since you are actually doing a 'fix' more than a mod. but on things that work pretty darn well as shipped (which I do admit is somewhat rare), I don't like the approach of 'well, more is always better' and then seeing a bunch of caps dangling like antennas some distance away from the board.
on the modules I bought from ebay and amazon, I can't say that I'd want to tinker with the bulk storage caps in terms of just adding stuff and hoping it does good things and not bad things. the modules I've tried have not been problematic, and so I didn't see anything 'wrong' that needed fixing changing gain, perhaps, but nothing more than that.
I've seen tons of audio from ebay be really bad and need complete re-do's. these modules all seem to be well enough designed and implemented that its a step or two above the usual 'autoroute and ship' method that we all hate.
a circuit will have enough localized storage and bypass caps to do the job. to 'append' (lol) extra baggage to well designed boards is the thing I kind of object to. if the design was crap, ok, fine, mod the hell out of it since you are actually doing a 'fix' more than a mod. but on things that work pretty darn well as shipped (which I do admit is somewhat rare), I don't like the approach of 'well, more is always better' and then seeing a bunch of caps dangling like antennas some distance away from the board.
on the modules I bought from ebay and amazon, I can't say that I'd want to tinker with the bulk storage caps in terms of just adding stuff and hoping it does good things and not bad things. the modules I've tried have not been problematic, and so I didn't see anything 'wrong' that needed fixing
changing gain, perhaps, but nothing more than that.I've seen tons of audio from ebay be really bad and need complete re-do's. these modules all seem to be well enough designed and implemented that its a step or two above the usual 'autoroute and ship' method that we all hate.
As long as you're not using a wooden/plastic enclosure, the best thing to do is to attach the bottom of the sanwu boards to a heatsink - the easiest solution is to attach the boards to aluminium/metal enclosure itself, using thermal pads or similar material. They do not heat up that much, unless you're driving them to the max....
Thanks for the reply. The case is wooden, but if I have too will put some heatsinks on the amps.
I was more concerned with the psu heating everything up more than the amps, so just wanted some air movement within the case itself.
This is not my amplifier. It is "Thrashcanz". It appears he modded one to do some A/B testing.
High pitch noise is barely audible after gain reduction, but it is there with every source I tried. I have not tried a resistor.
Thrashcanz replaced the smd capacitors and heard a difference in bass response at higher volume. Could I just add a 1000uF or someting on the power terminals instead of having to desolder the SMD caps?
Yes, capacitors add capacity when in parallel, plus ESR equivalent reduces (increases current delivery).
I found out that the grounding is very important to reduce hissing. just make sure it's grounded. hope it helps
look at that:
there is a stereo version of our beloved sanwu 3118 board.
it comes with bluetooth and bigger inductors.
DC 12 v 24 v Bluetooth Empfnger TPA3118 Stereo digital power verstrker 30 Watt + 30 Watt fr diy lautsprecher auto in audio-eingang: Bluetooth empfnger versorgungsspannung: 8 ~ 26VDC (gleichstrom) verpolungsschutz 2X30 Watt stereo-endst aus auf Al
there is a stereo version of our beloved sanwu 3118 board.
it comes with bluetooth and bigger inductors.
DC 12 v 24 v Bluetooth Empfnger TPA3118 Stereo digital power verstrker 30 Watt + 30 Watt fr diy lautsprecher auto in audio-eingang: Bluetooth empfnger versorgungsspannung: 8 ~ 26VDC (gleichstrom) verpolungsschutz 2X30 Watt stereo-endst aus auf Al
I am looking to buy a pair of mono amps to drive a pair of speakers.
TPA3118 PBTL Mono Digital Amplifier Board 1x60W 12V 24V Power Amp | eBay
TPA3116 50W*2 digital amplifier board PBTL 100W mono power amplifier 12v 24v AMP
I presume these two are some of the better ones to look at? If I were to choose one, would there be a clear winner?
Do either these exhibit any pop when turned on or off? My Audiobah clone does not pop, but am unsure if others have suppression or if it needs to be added. Thanks in advance.
TPA3118 PBTL Mono Digital Amplifier Board 1x60W 12V 24V Power Amp | eBay
TPA3116 50W*2 digital amplifier board PBTL 100W mono power amplifier 12v 24v AMP
I presume these two are some of the better ones to look at? If I were to choose one, would there be a clear winner?
Do either these exhibit any pop when turned on or off? My Audiobah clone does not pop, but am unsure if others have suppression or if it needs to be added. Thanks in advance.