I was about to ask the same. I notice you've used elna silmic on the input too. I once tried them on the input stage on an earlier (different) build and found a lot of sound detail went missing. Went back to the nichicon golds with immediate improvements.
This obviously depends on the sound character of the other components. I'm satisfied with the result.
I noticed one of the 50 volt capacitors, which is 470 uf, what was available, nichicon 63v 680 uf. but at the same time I changed the capacitors in the power supply, increased the capacitance, it is difficult to judge the result without a direct comparison, it felt a little more bass, the heating may have decreased.
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This board may be a case study as far as engineering decisions and compromises being let down in the supply chain. The screen print on the pcb calls for 3x1000uf caps, the factory installs the equivalent of 2470uf in total values (presumably the compromise), but the actual capacitance values add up to only 1960uf in total (comparing two boards in my possession). All I will say is that by bumping up the actual capacity to 2310uf (actual combined total) I got a more significant improvement from this board model (on scale) than I have by upgrading other model 3255's with better components. I'm sure it could still sound better but doing a full upgrade of everything (with an observable improvement) may be obscuring the point that one of those upgrades just brought the board to spec.
I agree, this is very similar to savings in production, and the build quality of my copy was not very good, the cooling was poorly implemented, the board was deformed from the radiator fasteners.
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Has anyone tried the green board with the onboard 100hz low pass filter?
https://a.aliexpress.com/_EybLzOV
https://a.aliexpress.com/_EybLzOV
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I have upgraded model but I get low treble detail. It sounds like the low pass filter rolls of some treble. My speakers are 8 ohm, PSU is 600W LLC which is set to 45v. Do you have the same problem?
On the updated version, the high frequencies play in great detail, the low frequencies are a little lacking. But to be honest, after comparing the mini amplifier on tpa3116, homemade on tpa3255 and the Yamaha rx-397 receiver (I have a video on my channel), I came to the conclusion that the differences are very little noticeable. Perhaps everything depends on my acoustics, or maybe all these devices produce an acceptable level. For myself, I concluded that if you like how it plays, just listen and enjoy. Attempts to find a subtle improvement in sound leads to eternal dissatisfaction with their own equipment and the search for new ones. The main thing is to stop in time)
I have Hypex NC400 and Cambridge Audio 851W and both have much better treble detail. The board I have may have a problem. I wonder if the multilayer ceramic caps on the LP filter line may cause roll off?
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I wanted to use just for bass with the 100hz filter so I guess any treble problem wouldn't be an issue for me. Does the filter provide a good low pass?
Is your 3255 amplifier using the black & gold nichicon caps on the input side or the red mica style capacitors?
Cool, the one with the red caps I referenced come with 4 x 3300uf filter caps and doesn't sound as good as the other imo. Can only recommend what I published earlier - replace the single skinny 470uf 50v cap with a 1000uf capacitor to get it up to design specs first. It will sound different.
I think you are familiar with the design specs. Do you know if the output filter corresponds the design specs? (For 8 ohm)