I have tried the eBay blue knockoff TI EVM board, the 3E audio board, and recently my own that basically followed the TI EVM schematic and none of them have a turn off pop? Turn on is graceful as well. Could this have something to do with the Cstart Pin 15 voltage ramp up pin capacitor value? The blue knockoff boards all have both error light on at startup and during normal operation though.
The amp is very quiet though. Absolutely no hiss with ear pressed to speaker cone. I am using DC-DC step from 12v battery to 51v.
The amp is very quiet though. Absolutely no hiss with ear pressed to speaker cone. I am using DC-DC step from 12v battery to 51v.
So, which TPA3255 amp do you recommend?
TPA3255-2CH-260W | 3e Audio is not going to ship to my location.
I cannot find TI TPA3255 EVM.
Finished chinese TPA3255 amps seem to use 37V voltage regulators which are not safe for 48V operation.
I cannot choose one.
TPA3255-2CH-260W | 3e Audio is not going to ship to my location.
I cannot find TI TPA3255 EVM.
Finished chinese TPA3255 amps seem to use 37V voltage regulators which are not safe for 48V operation.
I cannot choose one.
Hi Cowcat
If you want to play around and have fun or try something = DIY then use the chinese boards - 36V supply is enough for at home.
TI 3255 EVM you will find in the Texas Instrument store (you have to register) about 140 Euro actually
the 3e 3255 is well designed and is about 90 euro
or you want to try a board from X = xrk971
chris
I want the chinese boards since they are cheap and readily available.
However, I am not sure if finished chinese TPA3255 amp products are safe with 36V power, let alone 48V. I'm not even sure that they work properly.
Chinese TPA3255 amp boards do not have volume knobs or power switch.
I am not interested in playing around. I just want to make something work as soon as humanly possible without spending too much money.
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Corretion : Some chinese TPA3255 amp boards have volume knobs and power switch.
Chinese TPA3255 amps that use LM2575T-12 voltage regulator may be able to work with 36V power although I don't know whether there are other pitfalls.
Chinese TPA3255 amps that use LM2575T-12 voltage regulator may be able to work with 36V power although I don't know whether there are other pitfalls.
Also check 12V voltage regulator on the board. Most 12V voltage regulators on TPA3255 boards have maximum input voltage of 40V. I don't know if it's safe to use a 36V power supply with 12V voltage regulators that have maximum input voltage of 40V.
Hi Folks
I have 3 x 3e audio TPA3255, I set them as follows:
1. Master
2. Slave 1
3. Slave 2
as per manual (link below)
http://www.3e-audio.com/wp-content/uploads/2018/07/DS_EAUMT-0260-2-A_Rev1.0.pdf
for the slaves I removed R39 and Added R40 0ohm 0603 resistor (from DigiKey) linked the boards with IOP and IOM as per the manual.
Now master is working but both slaves are not, boards are on but not producing any sound. what else do I need to do add j6? just solder wire? both blue jumpers in the attached image
Also, I'm I set them as SE and there is a bit hiss on zero volume how can I reduce that?
I have 3 x 3e audio TPA3255, I set them as follows:
1. Master
2. Slave 1
3. Slave 2
as per manual (link below)
http://www.3e-audio.com/wp-content/uploads/2018/07/DS_EAUMT-0260-2-A_Rev1.0.pdf
for the slaves I removed R39 and Added R40 0ohm 0603 resistor (from DigiKey) linked the boards with IOP and IOM as per the manual.
Now master is working but both slaves are not, boards are on but not producing any sound. what else do I need to do add j6? just solder wire? both blue jumpers in the attached image
Also, I'm I set them as SE and there is a bit hiss on zero volume how can I reduce that?
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I have bought 2 TPA 3255 s
1st one a direct purchase from Yuan Jing
2nd one via Lazada in Malaysia. It was significantly cheaper . Claimed to have Elna caps .
What i received is the exact same as the earlier one . No Elna caps but who cares.
Big caps are Samwha or something like that
I am using 48V 600W Meanwell switching PSU
No probs at all . They sound good.
I might change a few bits just for fun but they would have to be components that are thru soldered on. I wouldnt dare surface solder as the components are tiny
1st one a direct purchase from Yuan Jing
2nd one via Lazada in Malaysia. It was significantly cheaper . Claimed to have Elna caps .
What i received is the exact same as the earlier one . No Elna caps but who cares.
Big caps are Samwha or something like that
I am using 48V 600W Meanwell switching PSU
No probs at all . They sound good.
I might change a few bits just for fun but they would have to be components that are thru soldered on. I wouldnt dare surface solder as the components are tiny
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Page 11 " Please make sure all of these change have been done before power up the boards.Since the board default setting is master mode, so what you should do is set the other one board in slave mode, you can set slave mode 1 or slave mode 2 with just inverse the polarity.Besides, remove the resistor R39(top side, remove heat-sink) and solderR40with one 0ohm0603 resistor, this also marked on the bottom of the board show as below.
Slave mode 1: (Figure 8)Connect the master OSC_I/O to the slave OSC_I/O with same polarity (IOP to IOPand IOM to IOM).
Slave mode 2:Inverse the polarity of OSC_I/O(IOPto IOM and IOM to IOP)"
You could have used a piece of wire or just a blob of solder instead of a 0ohm resistor. But that won't matter.
Did you connect the wires (red lines) from the master to the slave boards?
FYI I'm using 2 of the same boards with the 3e audio dsp without any noise, both running as master sharing a 24v or 48v power supply.
Did you twist the SE input cable any keep it away from noise?
I did connect the wires (red lines) soldered R40 and Removed R39 but it never worked the boards are on but no sound.
Then I connect J6, the master board fault LED was blinking. So no joy either.
I had to reverse everything back to master but I lost one R39 SMD, do know the value of that?
Anywho, I revived one board and one still down due to R39 thingie.
Noise is gone and everything is silent.
To bad this didn't work out, but good that the noise is gone. Any idea why that is?
No values of board components to be found in http://www.3e-audio.com/wp-content/uploads/2018/07/DS_EAUMT-0260-2-A_Rev1.0.pdf
R39 is a resistor, you can measure it (Ohm) on one of your other boards.
Otherwise email or skype (3e Audio) and ask them.
No values of board components to be found in http://www.3e-audio.com/wp-content/uploads/2018/07/DS_EAUMT-0260-2-A_Rev1.0.pdf
R39 is a resistor, you can measure it (Ohm) on one of your other boards.
Otherwise email or skype (3e Audio) and ask them.
I just changed fake NE5532 for original NE5532. I think some changement on Bass and High adjustment are the result.
My DC-DC converter dont Step-up... I don't know why.
But amp is really good. After this changment and with the true capacitor size its one of the best china amps.
:-D
My DC-DC converter dont Step-up... I don't know why.
But amp is really good. After this changment and with the true capacitor size its one of the best china amps.
:-D
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Tpa3255&tda7498 who is winner?
Hi mates again from Ukraine. There was some changes in my setup since my last input here.
Was Canton SC-L + tpa3255 blueboard with Bluetooth in black box . Chip have been fired and replaced by new one successfull. The amp was supplied by dc48v/1200w unit and by laptop brick from laptop 150w/21 volt without significant sound stage difference.
Sold out all these staff.
Now have : B&W DM603 S3 + blueboard tda7498 with aptx/Bluetooth 5 onboard (9$ on AliExpress) supplied by 150w /20v brick from laptop. This setup is sounding far better than previous one in approx 40 sq. Meters room still dont know why because the figures in wattages of amp and Canton speaker datasheet saying they outperform b&w+tda7498. But result is somewhat i didnt expected.
Now about to get blue tpa3255@50$ with two big Elna ( samwha) caps from AliExpress which is highly intencively discussed here to check and compare. Will keep informed. Cheers!
Hi mates again from Ukraine. There was some changes in my setup since my last input here.
Was Canton SC-L + tpa3255 blueboard with Bluetooth in black box . Chip have been fired and replaced by new one successfull. The amp was supplied by dc48v/1200w unit and by laptop brick from laptop 150w/21 volt without significant sound stage difference.
Sold out all these staff.
Now have : B&W DM603 S3 + blueboard tda7498 with aptx/Bluetooth 5 onboard (9$ on AliExpress) supplied by 150w /20v brick from laptop. This setup is sounding far better than previous one in approx 40 sq. Meters room still dont know why because the figures in wattages of amp and Canton speaker datasheet saying they outperform b&w+tda7498. But result is somewhat i didnt expected.
Now about to get blue tpa3255@50$ with two big Elna ( samwha) caps from AliExpress which is highly intencively discussed here to check and compare. Will keep informed. Cheers!
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Got tpa3255 board today . Of course no Elna caps, just samwha 63v/4700mkF but who care? Without doubt this board is outperform all my previous boards I tried: tpa3116, tpa3116 doublechips, tda7498, tpa3255 blackbox with Bluetooth 4.0 . And oldschool Marantz sr6400 (100w#8hom). This is the first time ever I am afraid to turn volume knob more than 60% on B&W DM603s it is getting very loud endeed without distortion - the right way to burn out tweeters on sudden music peaks.
From the other side I found the heatsink is 50 celcium degree , checked the thermopaste it is ok. Does anyone checked the sink temperature? Think 50 degree on almost idle level is not ok, what do you think mates?
This board is deadly silent. Think will keep it for a while before icepower or hypex arrival
From the other side I found the heatsink is 50 celcium degree , checked the thermopaste it is ok. Does anyone checked the sink temperature? Think 50 degree on almost idle level is not ok, what do you think mates?
This board is deadly silent. Think will keep it for a while before icepower or hypex arrival
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I have tried same board and the error lights are always on by default when working. Does yours do that? I was unable to get more than 48Vpp out of it in BTL despite the PSU being 51v. Oscope shows it clips at 48Vpp - not sure why that is. Should have been able to go to 80Vpp easily. Please let me know what your max output is without clip.