This board, usually called the YJ Blue/Black board has quite a history, allied to this forum!
It was effectively 'designed' (at least as far as schematic/layout) by DIYAudio member Danzz; his schematic was copied/interpreted and produced by Yuan Jing, followed by a host of Taiwanese clones.
Nice
Do you know if the use of Box Capacitors really contributes anything to the sound?
Not specifically so, I don't believe. The YJ board was arguably one of the most modified TPA3116 boards; whether that was due to it's popularity or it being a poor performer as standard is open to question.
This page offers a lot of empirical advice:
TPA3116D2 Boards
I can add a third reason for this:
the fact that it's all thru-hole components..
It makes it much easier to change/connect to, rather than SMD components.
Amazing!
thank you, will go over it
1. In class-D amplifiers, the outputs have LC filters that convert a duty cycle to an analog Voltage. The main feature of UCD design is that feedback is taken after this filter so any core distortion is minimized.
2. Linear amps need a small output inductance "build-out" to prevent the speaker wires from shorting the high frequency feedback. ie the feedback is taken before this choke (and resistor) so that speaker + wire capacitance can not make the amplifier unstable.
3. TI has advertised "inductor-less" class-D amps, but they depend on the inductance of the speaker, and they are talking about bridged outputs that switch out of phase to reduce common mode currents that cause radio emissions. IE this is better than some other designs but not perfect, maybe "good enough" to pass radiate regulations.
2. Linear amps need a small output inductance "build-out" to prevent the speaker wires from shorting the high frequency feedback. ie the feedback is taken before this choke (and resistor) so that speaker + wire capacitance can not make the amplifier unstable.
3. TI has advertised "inductor-less" class-D amps, but they depend on the inductance of the speaker, and they are talking about bridged outputs that switch out of phase to reduce common mode currents that cause radio emissions. IE this is better than some other designs but not perfect, maybe "good enough" to pass radiate regulations.
@Yatsushiro: A fine overview of TPA3116 boards. The "YJ Blue/Black" board seems among the most serious implementations but is still sold at an attractive price (12$).
@steveu: Nice feature of the UCD concept. I only know the basic principle of UCD amplifiers, not their particular features. The "small output inductance" you mention for linear amplifiers, is that the one in the Thiele element?
PAM8403, PAM8610 and such low power amplifiers can function without an output filter. In my view, the TPA3116 is simply too powerful and low-impedance for such operation above 12V.
@steveu: Nice feature of the UCD concept. I only know the basic principle of UCD amplifiers, not their particular features. The "small output inductance" you mention for linear amplifiers, is that the one in the Thiele element?
PAM8403, PAM8610 and such low power amplifiers can function without an output filter. In my view, the TPA3116 is simply too powerful and low-impedance for such operation above 12V.
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If you mean "Le - Voice coil inductance measured in millihenries (mH) (measured at 1 kHz)" as used in Thiele/Small speaker parameters, no, that is the speaker coil inductance, not part of the amplifier.
Thiele/Small parameters - Wikipedia
Amplifiers that use feedback can not tolerate certain loads, so they include a "build-out" inductor and/or resistance as a minimum load impedance at high frequencies.
Thiele/Small parameters - Wikipedia
Amplifiers that use feedback can not tolerate certain loads, so they include a "build-out" inductor and/or resistance as a minimum load impedance at high frequencies.
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