I tried compiling all the recommended mods for the yj blue/black board. Hope it helps folks find things.
Thanks! Exactly what I was looking for
Sent from my SGH-T999V using Tapatalk
I tried compiling all the recommended mods for the yj blue/black board. Hope it helps folks find things.
That's a great idea Prezden. I should mention within the last few weeks, I've been re-thinking the use of 1,000uF and greater capacitance on the DC decoupling caps in my TPA3116 and TPA3110 amps. It started when I assembled a ChengZhi TPA3116 amp for a TPA3116 amp tour for members of AudioCircle. The ChengZhi amp had a pair of stock 470uF/25V Sanyo OSCON-clone caps and the amp sounded smoother than either of my amps. I decided to swap in a pair of Panasonic FM 470uF/35V caps into my Yuan Jing TPA3110 blue amp (Danzz's design), and I found the amp to sound smoother and more musical. The tonality improved and the amp just sounded more relaxed and more fun to listen to. I then did the same change with my Sure Electronics TPA3110 amp, and I got the same improvements. In both amps, I have a Panasonic FM 2,200uF/25V on the power supply input on the board. I did the same with the ChengZhi amp too, and I have to say the bass response is more impressive with the smaller caps close to the amp IC and the larger cap at the power supply input.
I am going to try some Panasonic OSCON 330uF/25V caps as wushuliu has recommended. These may be even better. I've also ordered the TDK 200nF/250V X7R ceramic caps for the bootstrap caps and a set of the Coilcraft inductors as we'll. These will go on another Yuan Jing blue amp.
By the way, the ChengZhi is a nice amp and it does it's thing to avoid turn-on and turn-off thumps. It's a shame that they are no longer available as far as I can tell. I never had a problem with thumps, but for people who do, the ChengZhi amp might be a good solution. Aside from adding the Panasonic FM cap, a Panasonic EVJ 50k volume pot, connectors, wiring and a compact Aluminum chassis, the amp is stock, and it sounds impressive. I still prefer my amps over it, because I think the parts on my amps improve the performance. The TPA3116 amp tour featuring this amp is covered within the Cheap and Cheerful forum at AudioCircle.com:
http://www.audiocircle.com/index.php?topic=124771.0
I think that any amplifier with high gain is susceptible to oscillation if the input has too much capacitance and not low enough impedance to ground. I experience this when bread boarding op amp servo circuits. Have not has a problem with the TPA amp but there must be a reason why 1uF up to 5.6uF caps are used - why not bigger?
I tried compiling all the recommended mods for the yj blue/black board. Hope it helps folks find things.
Great minds think alike.
I recently re-read this entire thread, trying to keep notes as I went along.I went ahead and added some of my notes to the TPA3116D2 Boards wiki here on diyAudio. The wiki was suggested a few times throughout the thread, but never got any momentum behind it. I'm hoping the stuff I added will give it some traction.
Note that I didn't add any original content, just tidbits I pulled from this thread (and a couple other big threads on other forums). I tried to keep track of all sources of information and attribute accordingly. I haven't had time to review closely, only to do a quick skim.
Hopefully others find it useful. I still have more notes to add and the formatting needs to be cleaned up a bit.
I'm going to try these Nihon Kohden (Tamura) TTOK transformers on the inputs. The transformers will do unbalanced to balanced conversion, allow the input coupling caps to be removed, and provide galvanic isolation from my source. They might also sound quite nice and smooth
I would recommend a small test first.
Connect a voltmeter to the speaker and measure and any DC that might be there.
Connect the -in and +in together on the IC side of the caps while monitoring the voltmeter on the speaker leads.
If there is no change then the transformer can be connected without caps.
If there is a change(for the worst) then you might want to consider using at least one cap to block the DC.
Just an idea.
There has been a small amount of confusion with the data from TI.
The data sheet says 10uH for all loads but the demo board lists 10uH, 22uH, or a ferrite bead on the schematic and 10uH in the BOM and has a picture of the board showing 22uH.
I am using 10uH.
Last edited:
This paper on Class D design goes back a few years but is still very useful.
Here's an excerpt pertaining to LC Filter Design.
Here's an excerpt pertaining to LC Filter Design.
Attachments
I took the stock photo of the JY Blue/Black Danzz design board and annotated it. I think I got everything right. Hopefully others find this helpful.
An externally hosted image should be here but it was not working when we last tested it.
-3dB points of specified filter doesn't differ if chip is 10kHz or 10Mhz
But the whole point (in SMPS as well) is the higher the frequency the smaller the inductors.
If I push the 3dB point from 40kHz to 80kHz it will still get rid of the switching frequency to a level that is acceptable to me.
And if 400kHz is too low the 3116 can go to 1200kHz.
Being a bit pedantic here but the LC filter comprises only the inductor and 0.68mf cap, the other components after these are for the EMI snubber.