I've seen that one of the more common mods to this type of amp is to increase the capacitance of the power supply caps. Is that what you are implying? That in addition to getting better quality low ESR caps, I should also look for caps with higher cap value?
I may be wrong, but I think I've also seen that if the psu caps have low enough ESR that increased capacitance may not be necessary?
Hi chaps, I just performed the Bootstrap mod on my YJ TPA 3116 Black board using the following:
Vishay 330pf 100v Caps
Multicomp Resistors 10R .25 watt
Fired her up and the Resistors started smoking, should I have used .5 watt or have I done something wrong (it's wired up as a mono PBTL), I connected the small caps on the reverse of the board - one end to the outer leg of the Bootsrap caps on the upper side, via each resistor to a good ground (scratched area away from any traces), pretty much as the previous examples have shown on this site.
I'm hoping its just the wrong wattage resistors.
I removed the offending resistors and fired her up and all playing lovely still, just would like to get this mod done right, as members mention positive results after it has been done.
Any ideas?
Vishay 330pf 100v Caps
Multicomp Resistors 10R .25 watt
Fired her up and the Resistors started smoking, should I have used .5 watt or have I done something wrong (it's wired up as a mono PBTL), I connected the small caps on the reverse of the board - one end to the outer leg of the Bootsrap caps on the upper side, via each resistor to a good ground (scratched area away from any traces), pretty much as the previous examples have shown on this site.
I'm hoping its just the wrong wattage resistors.
I removed the offending resistors and fired her up and all playing lovely still, just would like to get this mod done right, as members mention positive results after it has been done.
Any ideas?
Clengman,
first measure then change something. 1000uF is normally adequate bulk capacitance. Filter frequency with 33uH+680n is not a problem but also not "optimal". Inductor saturation is more of an issue if occurs.
If you wanna change the caps, even less is okay if ESR is low enough. So 820uF 25V or 35V is okay, like Panasonic FM or FC series.
first measure then change something. 1000uF is normally adequate bulk capacitance. Filter frequency with 33uH+680n is not a problem but also not "optimal". Inductor saturation is more of an issue if occurs.
If you wanna change the caps, even less is okay if ESR is low enough. So 820uF 25V or 35V is okay, like Panasonic FM or FC series.
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I agree. Better to have a diagnosis before trying to apply a cure.
A little earlier, specd mentioned that on a similar board he had purchased, the output and supply traces seemed inadequate to pass the needed amount of current. Out of curiosity, would the problem of inadequate supply traces manifest similarly to the problem of too high ESR on the supply caps? Is there an easy way to differentiate between the two problems? Checking voltage both before and after the psu caps?
Thanks for clarifying! So this would be an issue specifically if I'm getting a lot of noise from the power supply. Am I understanding correctly?
So I had a few minutes to play around this evening. First off, I was having a hard time reproducing the problem I described earlier. The high end was a little harsh at times, but I didn't seem to be losing the bass and mids the way I felt I was before. ???
I took a few measurements first at low volume and with the amp cranked. Measuring just the power supply (VCC to ground on the terminal block) I got 18.93V with the volume turned down all the way. At max volume it was down to 18.8V or so. I also measured the voltage on the + side of the supply caps. At low volume it was 18.7V. With the amp cranked it would drop to 18.6V if there was any signal at all. If the signal was either very bass heavy, or if it was very complex it might drop as low as 18.45V.
I don't know if these numbers are significant.
I've attached a photo of the board without the heat sink. Not sure where to look for HF decoupling caps.
Thanks again for all the help. I'm learning a lot.
I took a few measurements first at low volume and with the amp cranked. Measuring just the power supply (VCC to ground on the terminal block) I got 18.93V with the volume turned down all the way. At max volume it was down to 18.8V or so. I also measured the voltage on the + side of the supply caps. At low volume it was 18.7V. With the amp cranked it would drop to 18.6V if there was any signal at all. If the signal was either very bass heavy, or if it was very complex it might drop as low as 18.45V.
I don't know if these numbers are significant.
I've attached a photo of the board without the heat sink. Not sure where to look for HF decoupling caps.
Thanks again for all the help. I'm learning a lot.
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VOltage drop of <2%, i wouldn't adress this to be a real concern/issue. Additional hf-decoupling might help a bit at high volumes and EMI-wise, but, looking at the picture, implementing so is a bit tricky, as it may colide with the heatsink.
Those thin tracks are really not optimal but at low/medium volume i don't see a problem here. It's just some increased track-resistance/impedance - still small compared to the speakers resistance/impedance. They just heat up more than widther traces.
To be honest, i'd leave it as is if it works. Rolling caps is up to you, don't see a real advantage here.
Those thin tracks are really not optimal but at low/medium volume i don't see a problem here. It's just some increased track-resistance/impedance - still small compared to the speakers resistance/impedance. They just heat up more than widther traces.
To be honest, i'd leave it as is if it works. Rolling caps is up to you, don't see a real advantage here.
So this isn't an ideal implementation. It's okay for now. I do plan to work on more projects in the future. I'm trying to read through more of the thread to find the answer, but maybe someone can comment here. Is there a 3116 (single chip "2x50W") board that's currently available on aliexpress or ebay that is considered to be better than all others?
I see the two below listed on aliexpress. Are they better than the one I got from the standpoint of board design?
I see the two below listed on aliexpress. Are they better than the one I got from the standpoint of board design?
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And I would like to know if any of the 2.1 boards have been identified as best (before or after recognized mods). I know John8 did some detailed analysis and mods but that seems be several years ago.
Not sure if you were responding to my post. My portable design really needs the 2.1 TPA3116 board. I have one and I have changed the sub's LP frequency by changing the two capacitors in the sallen-key op-amp circuit.
I like the fact that: (a) the mono summer & LP is built in; (b), the separate volume control for sub and L-F channels allows me to match driver levels w/o passive components; (c) The overall volume control is very convnient once I've matched levels; and (d) the current board I have takes two fully charged SLA-AGMs (26.6v) without issues.
I was just wondering if anyone (such as John8) had come to the conclusion of which TPA3116 2.1 board came out as best.
No.
I responded to this post:
Which 2.1 board do you have and what do you not like about it?
There are quite cheap crossover pcb's available.
Your power supply with two 12V sla batteries is good for almost all of them,
Just use the center tap to get the +/- supply (or use two 9V blocks).
Building your own crossover on perf-board is no magic and a nice diy project.
For a mobile system you might consider a 1.1 configuration, where everything is mono, which easier for the opamp circuits.
With a seperated crossover the 3118 pbtl board might be an option.
Your supply voltage allows for other amplifiers.
You should also consider the TAS5611, TDA8932 or TDA7498.
Well, your thinking is spot on so here goes ...
I have this board w/LP Fc modified to 876 hz (up from 107hz)
I am already building PLLXO to manage bass excursion limits and baffle step compensation, can't add any more passive line level filters. The +/- preamps and xovers are not suitable as ground becomes a problem when using the same battery set to power both (e.g., the pre-amp signal gnd is +12v while the amp signal gnd is 0v).
I considered mono. In the end I built this.
Woofer is a Scan-speak W22-3445G 8", 4ohm 91db at 1w/m. This driver gave me the best compromise between SPL and bass extension. The L-R are Goldwood sealed back 5", 4 ohm. I went with two to keep up with the woofer.
I don't see the TAS5611 in 2,1 configuration (on eBay), TDA8932 is underpowered for my app. TDA7498 is possible as is the TAS5630s I've been looking at. But the one TAS5630 in 2.1 configuration I see seems to be force fitted into the Yuan Jing 2.0 board.
Testing the above unit and amp, I hear some distortion after several minuts of near max volume. Heat-sink is only warm. Distortion goes away after 10 minute rest. Could be my underpowered 24v SMPS wall wart is not up to task - cuts out on max bass tracks (and my SLA-AGMs are old and I haven't replaced them yet).