What do you think about gel batteries? Three 6V in series will give about 21V which seems perfect. They are cheep and easy to charge. Do you know any disadvantages comparing to LiFePO4? Size and weight doesn't matter
Positives favouring LiFePO4
- SLAs can blow up, it's rare but it can happen. LiFePO4 cannot, it's simply impossible.
- LiFePO4 have lower own noise
- LiFePO4 have better current handling capacity
- LiFePO4 can be recharged over 10 times as many times before loss of capacity
- LiFePO4 work with standard SLA chargers but it's recommended to use dedicated chargers for full capacity and life time
Positives favouring SLAs
- SLAs are cheaper
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Yeah. Use a BMS PCB. But the same is true for SLAs. Deep discharge SLAs too far just once, and you can throw the battery away basically. It will never regain full capacity, own level will have risen by a factor of ten, and current handling will be severely affected.
These guys seem to have pretty fair prices on batteries, both european and us warehouses
Batteries & Accessories>LiFePo4
Batteries & Accessories>LiFePo4
Battery bypassed with a big reservoir cap (batteries have an internal resistance) and small high freq cap ... what's not to love?!?
Yes stay away from LiPo unless you know the differences and you know what you're doing.
Good 'Ol SLA batts, safe and easy. "Acid in the living room", SLA are used in computer UPS and safety lights all over the place. Just know what you're doing.
How about someone post a nice, easy and safe 12V SLA recharge circuit for less than 5 Ah and more than 5 Ah.
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For quality lifepo4 stuff I'd recommend
EV-Power | Your Complete Power Solutions - in Europe
BatterySpace.com/AA Portable Power Corp. Tel: 510-525-2328 - Powerizer Battery Official Site - in the US
Otherwise there's plenty of stuff on ebay/aliexpress and so on
EV-Power | Your Complete Power Solutions - in Europe
BatterySpace.com/AA Portable Power Corp. Tel: 510-525-2328 - Powerizer Battery Official Site - in the US
Otherwise there's plenty of stuff on ebay/aliexpress and so on
I am using this:
12 Volt 5 AmpH SLA Battery with F1 Terminal : Amazon.com : Automotive
And I love it. Been using it for about an hour to two hours every night the last two weeks and the thing is still on its first charge! The difference between the battery and laptop brick is quite noticeable. The difference between the battery and a 12v 3.4 amp Pyramid regulated power supply, less so, but it's quieter, that's for sure. As you can see, I have been running this below 19v and am a happy camper. One of these days, when I see an old 19v pc brick at GW, I'll give higher voltages a try.
12 Volt 5 AmpH SLA Battery with F1 Terminal : Amazon.com : Automotive
And I love it. Been using it for about an hour to two hours every night the last two weeks and the thing is still on its first charge! The difference between the battery and laptop brick is quite noticeable. The difference between the battery and a 12v 3.4 amp Pyramid regulated power supply, less so, but it's quieter, that's for sure. As you can see, I have been running this below 19v and am a happy camper. One of these days, when I see an old 19v pc brick at GW, I'll give higher voltages a try.
...any one with the red YJ board check out polarity issues? reverse labeled speaker posts is how I think this thing comes....anyhow I got some listening time in. It sounds great in the mids and highs but is really lacking bass. I know someone mentioned a mod that improved bass response but god knows what page that was on. Any ideas??? I'm running with a 19v 5a power supply.
I would not invest too much unless you require portability.
I have tried batteries and notice no difference, perhaps someone could explain what I should to hear or not hear.
Running on batteries with a large bulk capacitor, changing input caps to larger and better suited type, changing bulk decoupling caps to ones with much higher ripple current capacity, and replacing the output filter with a ferrite bead filter will all improve bass response (as well as everything else).
Has anyone tried the Feixiang board yet? Still educating myself about amps, but it seems its construction is better than the YJ. I'm down to this or the Breeze for my first project.
New TPA3116 Class-D Amp Board
- Uses axial parts of capacitors and resistors, easy to change the values for different load and match the input impedance vs gain setting.
- No Via connections in any signal paths.
- Free copper pour under the power inductors (Minimum GND Noise interference)
- Build- In Stand-By and Mute Control pins/connectors
- Support Audio Direct-in or on board Vol. Pot.
- Support Power Input from DC Jack or Terminal Block with Fuse protection.
- Support 4 Ohm (50W x2) or 2 Ohm (100W x 1) Output config.
- Uses axial parts of capacitors and resistors, easy to change the values for different load and match the input impedance vs gain setting.
- No Via connections in any signal paths.
- Free copper pour under the power inductors (Minimum GND Noise interference)
- Build- In Stand-By and Mute Control pins/connectors
- Support Audio Direct-in or on board Vol. Pot.
- Support Power Input from DC Jack or Terminal Block with Fuse protection.
- Support 4 Ohm (50W x2) or 2 Ohm (100W x 1) Output config.
Interesting, looks like YJ are catering to those who wish to mod with their new version as well
Yuan Jing Audio - ON SALE! - TPA3116 Class-D 2.0 Stereo Amplifier Board [50W+50W] - $19.99
Yuan Jing Audio - ON SALE! - TPA3116 Class-D 2.0 Stereo Amplifier Board [50W+50W] - $19.99
That looks quite similar to the board I was designing... with the diferences that I use smd caps for the bootstrap, and also I give the chance that on top one can choose to use inductors and caps as a filter or use filter beads underneath the board...
By the way I tried the little 2x50w blue board that seems to be from feixang as well, as uses the same caps that in the their 2.1 board, and compared to the 2.1 board from YJ (compared only using the stereo channels, with a 4ohms 20w resistor in the sub output).
I like it much more, the midrange is clearer and the bass response its deep and clean, I used a couple of W5-1611SAF full range speakers in the already designed SARAH cabinet, and even the top end was rich with speaker that lacks a little in that section.
I like it much more, the midrange is clearer and the bass response its deep and clean, I used a couple of W5-1611SAF full range speakers in the already designed SARAH cabinet, and even the top end was rich with speaker that lacks a little in that section.
That looks real nice - a modders' delight with thru hole components on all parts needed and the first YJ board to use factory spec 10uH inductors.
I don't think there are polarity issues with the YJ board. I can't tell for sure (I need my scope for that) but I have a solid bass right now and absolutely no sign of out-of-phase errors.
What kind of speakers are you using?
High frequency, power-supply bypass capacitors should be small size, SMD and as close to the chip as possible.
Long trace, long lead and self-inductance of the cap will create too much inductance and swamp any very-high frequency bypassing of the cap.