I bought them form a Chinese ebay seller ($5 per pair). Apart from the improvement in the sound quality the markings on LM4562s went away after swapping them 2 or 3 times. Only NS logo is barely visible on them
Some chipcompanies do that, constant inductor and only change capacitor. But then they usually take a smaller inductor, like 2.2uH in 3116EVM.
But ideal 4 ohm without peaking is 10uH+1to 1.5uF.
Ideal 8 ohm is 22uH+680nF.
So like TI took 4 ohm inductor and combined with 8 ohm capacitor to get low peaking 4-8 ohm filter, you could try your 22uH with 1uF-1.5uF? Don't know if it is that simple?
BTW I think you can order at Conrad webshop? I saw Bourns 6A 10uH shielded in same footprint as standard, for I believe 70 cents
Irribeo, I went and bought these 5pcs 12x12x7mm 10uH 100 Shielded SMD Power Inductor's 5 4Amp | eBay.
They are probably not the best but they were easy to find Do you think I could keep the rest of the caps with then new 10uH coils? The tweeters in my speakers are super revealing so I belive it would sound better if I shifted the THD lower down in frequency.
I looked at the schematics from TI but I cant visualize how the different output caps will affect the graphs.. I dont mind if the tweeter is rolling of a bit to soon, so I guess I'm shooting for an overdamped system/falling response. So what filter caps should I use to get a low THD above 2Khz with a 10uH coil? I think impedance in that frequency is around 4ohm(ribbon trweeter).
I would greatly appreciate more input on filter design and how it would affect the sound!
They are probably not the best but they were easy to find
Do you think I could keep the rest of the caps with then new 10uH coils? The tweeters in my speakers are super revealing so I belive it would sound better if I shifted the THD lower down in frequency. I looked at the schematics from TI but I cant visualize how the different output caps will affect the graphs.. I dont mind if the tweeter is rolling of a bit to soon, so I guess I'm shooting for an overdamped system/falling response. So what filter caps should I use to get a low THD above 2Khz with a 10uH coil? I think impedance in that frequency is around 4ohm(ribbon trweeter).
I would greatly appreciate more input on filter design and how it would affect the sound!
I think it was Saturnus that said Original red board filter (is changed now) that had 5xxnF capacitors would create a narrow +/- 6dB peak around 12.500 hz and then roll off with 4 ohm load. But a peaking filter also effects transient respons, could maybe sound little smeared?? I now have a small tubebuffer connected that might do something like that LOL only high freq do not roll off but do lose definition/detail/information, low freq does roll off and has less detail too, dynamics are reduced, noise a little increased but somehow it doesn't sound unpleasant
i have some questons about this:
the black/blue board comes with a combo 10uH + 680nF.
is this the case for all of you guys?
i would like to use it with 4 ohm woofers.
what will the benefits of changing to 1uF caps be?
i pbtl´ed a red board 22uH + 680nF lke this:
what are the filter values after this mod?
now i want to use this board with a new speaker, that has three 8 ohmers in parallel.
the impendance diagram in their datasheet shows that they are 6 or 7 ohmish between 200 and 800 hz.
so i expect the impendance of the whole speaker to be something between 2 and 3 ohms.
what would be sufficient filter values?
Beuhgemeiste: you only use these amps for very limited frequency range it seems, so cutoff frequency would never affect frequencies in range I think?
Blueboard is close to ideal filter values mentioned, 1uF even closer. Don't know if it changes much.
Redboard pbtl I think is very heavily OVERdamped in this situation, value closer to 3uF will get closer to neutral filter damping. So how does redboard sound at this moment, I would imagine very dry, maybe little lifeless, missing drive kind of feeling? That is what I associate with overdamped, but is it like that?
Blueboard is close to ideal filter values mentioned, 1uF even closer. Don't know if it changes much.
Redboard pbtl I think is very heavily OVERdamped in this situation, value closer to 3uF will get closer to neutral filter damping. So how does redboard sound at this moment, I would imagine very dry, maybe little lifeless, missing drive kind of feeling? That is what I associate with overdamped, but is it like that?
i had the red pbtl board with a single fullrange 8 ohm driver in a br cabinet that is tuned quite low.
the music i mostly listened to sounds ok (old stuff jacob miller, dennis brown and some 80s dub ... things like this).
but with some songs i hadthe feeling that the voices are 'screaming'.
the music i mostly listened to sounds ok (old stuff jacob miller, dennis brown and some 80s dub ... things like this).
but with some songs i hadthe feeling that the voices are 'screaming'.
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Some recording should sound bad because they are awfull But if the recording isn't that awfull it could be something with filter too LOL
Maybe inductors saturating??? Or maybe speaker impedance is actually much higher at high frequencies, then it could be a peaking filter.
But now you were thinking of using them for only midrange duty? Or did you point out the 200-800hz frequency because impedance dipped there?
Yesterday I gave the little tubebuffer away, little time to findout how to improve if possible. Today already I got a call from my friend that it might be interesting for me to visit him to listen to little tube buffer grrrrrrrr he claims smps laptopbrick used for tpa3116 caused tubeamp to distort high frequencies and produce extra noise, he is testing another supply for tpa3116 and immediatly tubebuffer which has a seperate linear PSU improved a lot.
But if the recording isn't that awfull it could be something with filter too LOLMaybe inductors saturating??? Or maybe speaker impedance is actually much higher at high frequencies, then it could be a peaking filter.
But now you were thinking of using them for only midrange duty? Or did you point out the 200-800hz frequency because impedance dipped there?
Yesterday I gave the little tubebuffer away, little time to findout how to improve if possible. Today already I got a call from my friend that it might be interesting for me to visit him to listen to little tube buffer grrrrrrrr he claims smps laptopbrick used for tpa3116 caused tubeamp to distort high frequencies and produce extra noise, he is testing another supply for tpa3116 and immediatly tubebuffer which has a seperate linear PSU improved a lot.
Back to "screaming" voices the two elco's next to tpachip can also have an effect that sounds like that. Ringh has had very positive results with oscons there, wushuliu similar with hybrid caps. I heard the hybrids in that position too, they are nice, not sure yet if they are better then any other LOW value elco, because still trying others as well. 1500uF or 1000uF next to chip I am pretty certain that those values are not ideal, same thing for me the Panasonic FM and FR in that position are not ideal, voices sound little harsch. (while same time higher frequencies are less detailed and actually less in amplitude, so softer in strenght, not softer in sound)
Some recording should sound bad because they are awfull
Maybe inductors saturating??? Or maybe speaker impedance is actually much higher at high frequencies, then it could be a peaking filter.
But now you were thinking of using them for only midrange duty? Or did you point out the 200-800hz frequency because impedance dipped there?
Same results here.
I've done these 3 changes:
- Specified burns inductor
- wima mkp10 capacitor
- panasonic fc 1500uf 25v
voices are "harsh"
Very strange.
Hi All,
I've a YJ 2.1 in case. I'm tempted to modify the amp.
After testing the amp, I find the gain for the stereo channel is too low. I maxed out the volume just to get enough for my listening need.
After reading this forum and looking through the TPA3116D2 documents.
I've have a crazy idea,
According to the TI document
The single channel(sub) gain was set to 36db and the stereo is 26db
Can I just simply swap those resistor?
Theorically, it will still works right?
No big issue for the Sub as it is powered by a preamp
Do anyone have the schematic for this board as I want to confirm the resistor to swap
Please advise
Thank you
I've a YJ 2.1 in case. I'm tempted to modify the amp.
After testing the amp, I find the gain for the stereo channel is too low. I maxed out the volume just to get enough for my listening need.
After reading this forum and looking through the TPA3116D2 documents.
I've have a crazy idea,
According to the TI document
The single channel(sub) gain was set to 36db and the stereo is 26db
Can I just simply swap those resistor?
Theorically, it will still works right?
No big issue for the Sub as it is powered by a preamp
Do anyone have the schematic for this board as I want to confirm the resistor to swap
Please advise
Thank you
mono subwoofer amp on your board is in Slave mode, resistors do not match. better check posts by "john8" regarding sync output to sub amp too.
i don't think that for the gain setting smd resistors give any advantage in sound quality.
you can do that with any type of resistor.
I just want to get more gain on the stereo channel. not so much on the quality right now.
thanks. I'll pm John8 for help. from the documentation, the gain looks independent but I really need to make sure