I have not heard any LM3886 or similar amps but after reading many threads on them over the years the overall gist I got was that 3886/chip amps need a lot of attention paid to power supply and component quality to really make them sound their best. TPA-based amps on the other hand like the TBI Millenia sound excellent with stock reference design and parts. On another forum the TBI has held its own against $$$$ amps including Pass and NCore and other very expensive gear. I have rarely read LM3886 as being at that level unless, as I said, a lot of attention (and money) is spent on power supply and parts quality e.g. MyRef, etc.
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Don't you love it when the entire amp and SMPS brick costs less than one of the big honkin electrolytic caps on the power supply for the class A amps?
I designed a portable media player containing a TI TPA3100D2 and I am very impressed. I have LM3886 parts in the drawer and I'll think they will stay there.
I think the LCD backlight draws more juice than the TPA3100D2.
I am driving the Dynaudio Geminis (4ohm MTM) and the sound is just fine. Listening to station on the FM that is at least 75miles away and is still great, just in mono @17dBuV. Modern day semi's are just spectacular.
A project I'd like to do is the 2.1 amp as in the TI eval pcb.
FYI, I am seeing some really cheap pcb's out there, un-shielded inductors = ugly and EMI noisy.
I think the LCD backlight draws more juice than the TPA3100D2.
I am driving the Dynaudio Geminis (4ohm MTM) and the sound is just fine. Listening to station on the FM that is at least 75miles away and is still great, just in mono @17dBuV. Modern day semi's are just spectacular.
A project I'd like to do is the 2.1 amp as in the TI eval pcb.
FYI, I am seeing some really cheap pcb's out there, un-shielded inductors = ugly and EMI noisy.
Thanks for the tip! Suddenly the time to think was over. Now it's time to wait for delivery 
Very interesting. How sensitive are the speakers and how hot of a source signal?
I've yet to package mine up with the 20V 3A SMPS brick I have... Hell, I barely have enough time to eat, let alone play with audio toys.
I was listening to live365 24/7 Baroque internet radio (128k) connected to the new 3116 board at my usual listening level (not background).Very interesting. How sensitive are the speakers and how hot of a source signal?
I've yet to package mine up with the 20V 3A SMPS brick I have... Hell, I barely have enough time to eat, let alone play with audio toys.
I pulled the AC plug on the 24V 6.25 SMPS and connected the DC of the 14V 4A brick and connected the AC. There was no difference in volume but the heatsink cooled and is probably not necessary. There was no loss in volume with either CD, FM or MD
My speakers are vintage 15ohm Tannoy Yorks which really seem to suite these D-amps.
It took just about a month to arrive, worth waiting for, it came very well packed.
The 2.1 board must have one chip bridged to mono 100w
The Ti spec sheet describes the circuit to make it mono in detail. I am just wondering if it's possible to mod the stereo boards without chopping them up too much.
Kyle
Might be cheaper and easier to purchase a 2.1 board and bridge the 2 50w stereo channels to 100w mono thus giving 2 x 100w?
I should have explained my self in more detail. I thought it'd be handy to have some monoblock style amplification for using with my miniDSP so I can have a pair of active woofers. Getting the extra power and fidelity for only $16-20 a side + power supply seems like a steal.
I ordered a stereo board and the fancied up 2.1 model that was on sale yesterday. When I get them I'll start poking around. I'm away the last 2 weeks in September so it's looking like I won't be able to play until Oct.
Kyle
KJA,
You mean 10uH coils not mH, right? I am curious how they sound with the 22uH coils because my design has always used 10uH as specified in the reference drawing. I noticed that you have started extensive modding of all the downstream caps with upgraded poly films and put bigger power supply electrolytics on the bottom. It's looking really good. FWIW, the design I have uses all SMD components downstream except for the coil and I think this keeps the size of the parts really small and yet it sounds really good to my ears. Those new coils are unshielded and now hang like antennas above the board. I wonder if it would reduce RF pickup by mounting them in flat orientation as close to the ground plane as possible on the bottom side of the board and use the ground plane to block RF pickup between the high impedance input side (on top) and the low impedance output side (on bottom). I actually have my unshielded coils mounted on bottom side.
You mean 10uH coils not mH, right? I am curious how they sound with the 22uH coils because my design has always used 10uH as specified in the reference drawing. I noticed that you have started extensive modding of all the downstream caps with upgraded poly films and put bigger power supply electrolytics on the bottom. It's looking really good. FWIW, the design I have uses all SMD components downstream except for the coil and I think this keeps the size of the parts really small and yet it sounds really good to my ears. Those new coils are unshielded and now hang like antennas above the board. I wonder if it would reduce RF pickup by mounting them in flat orientation as close to the ground plane as possible on the bottom side of the board and use the ground plane to block RF pickup between the high impedance input side (on top) and the low impedance output side (on bottom). I actually have my unshielded coils mounted on bottom side.
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Just bought two of these amps, one 2.0 and one 2.1. The latter I want to build into a nice enclosure, together with a PSU. I've been looking at this MeanWell 150W 24V 6,5A - any thoughts? I see that people are writing they can drive these with just 14V/4A. But, I wan't a PSU that's never going to get maxed out, no matter how inefficient the drivers are.
sure, just using this board to test various parts.... final orientation can be optimized. I'll hear how they sound sometime later today or tomorrow.
Has anyone purchased 2 boards or amps and just modded one and performed a side by side test, preferably blind with perhaps a 2nd party throwing the switch?
The reason why I ask is that I'm enjoying a stock $17 3116 board and cannot imagine how it could be improved so as I would notice.
I have followed the 2020 modding thread and it all appears very subjective and impossible to prove.
The reason why I ask is that I'm enjoying a stock $17 3116 board and cannot imagine how it could be improved so as I would notice.
I have followed the 2020 modding thread and it all appears very subjective and impossible to prove.