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Zek
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I don't think you can use that DC speaker protection for D-class amplifiers because it seems that the (-) connectors for the left and right channels are connected and that shouldn't be in D-class amplifiers (like in A / B class for example.
If you look closely at the print pattern, the +-of R-L is not separated and the negative terminal of R-L is connected. Such a circuit method cannot be used for BTL / PBTL amplifiers. The amplifier will break. I was inadvertently fooled by the appearance of the product with two two-circuit relays.
When I observed this relay board closely, I noticed a mistake.
The arrangement of the speaker connection terminals is as shown in the photo, and it was a product that could also be used for BTL/PBTL amplifiers.
The power supply of this board is AC12-24V, but it can also be used with DC17-32V.
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Even with this product, the negative terminals of the L/R channels are connected together, so it cannot be used with BTL/PBTL class D amplifiers.
In the first place, these products are for preventing pop noise when the power is turned on. It is not useful for eliminating pop noise when the power is turned off, which is a problem this time.
I know I also need a switch.
can't use this relay understand.
I contacted the manufacturer. He said. "Mute can be set to a high level of 1.5V to 12V to MUTE it before shutdown."
For power off pop avoidance, I think you can use this relay module. Get the 12V high trigger module then connect the +Speaker out to the normally open relay circuit. So that when power is cut off, the speaker is normally disconnected.
You need a buck converter to convert your supply's rail voltage to 12V to feed on this module.
Then for the trigger, use a voltage divider so that only small collapse in voltage (like -10V from rail supply) will trigger the turn off of the relay.
Also the relay will not turn-on until the supply rail reaches the desired voltage in the trigger input via voltage divider.
This one uses an optocoupler, so the trigger inputs are not connected on relay's DC power.
With the desired voltage on the trigger input, this is like having a high power voltage monitor.
https://www.aliexpress.com/item/4000109289135.html?
You need a buck converter to convert your supply's rail voltage to 12V to feed on this module.
Then for the trigger, use a voltage divider so that only small collapse in voltage (like -10V from rail supply) will trigger the turn off of the relay.
Also the relay will not turn-on until the supply rail reaches the desired voltage in the trigger input via voltage divider.
This one uses an optocoupler, so the trigger inputs are not connected on relay's DC power.
With the desired voltage on the trigger input, this is like having a high power voltage monitor.
https://www.aliexpress.com/item/4000109289135.html?
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To eliminate the power-off pop noise, it is necessary to detect the power-off as soon as possible and turn off the speaker output.
I devised various circuits for that purpose, but the residual charge of the decoupling capacitor of the amplifier board in the photo interferes with the DC power supply circuit. To avoid this effect, it is absolutely necessary to add a power switch and a relay that turns off the speaker circuit.
If you are good at such work, there is no problem, but I think it is better to purchase another amplifier board that does not generate pop noise. I would probably do that. (E.g. 3e audio TPA3255 2ch AMP board)
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Read the description carefully, they are completely separate.
Details：
UPC1237 power amplifier speaker, speaker, speaker protection circuit board
Turn on delay about 5 seconds
Audio DC output protection
Each channel uses a piece of UPC1237 special protection circuit chip
The resistance of the protection board uses imported resistance
"This version supports BTL amplifiers. The left and right channel circuits are completely independent. When using BTL amplifiers, you need to connect 2 independent power supplies"
I think this will only work on BTL amplifiers with split supplies. Since TPA3255 only has a single supply, each half bridge output is settling at half of the supply rail (virtual ground). For example if supply rail is 36V, + spk and gnd voltage will be at 18VDC. This will be detected by sengterbelle module as a fault.
This module will only work as startup delay if you don't connect the TPA3255's ground to the module.
For power down, supply rail will be slow to collapse so you need a mechanism for turning off the relay when a slight collapse of the power supply is detected. (ex. If your smps is 36V and the supply collapses to 30V, then the relay should be immediately turned off before the supply further collapse to <15VDC where most of the buffer stage is operating at)
This module will only work as startup delay if you don't connect the TPA3255's ground to the module.
For power down, supply rail will be slow to collapse so you need a mechanism for turning off the relay when a slight collapse of the power supply is detected. (ex. If your smps is 36V and the supply collapses to 30V, then the relay should be immediately turned off before the supply further collapse to <15VDC where most of the buffer stage is operating at)
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Thanks, everyone.
It's difficult to make a circuit. There is also deterioration in sound quality. So I buy a new board.
Does Hanzao3255 also have pop noise?
I want a board with excellent sound quality. Better than Shui Yuan TPA3255.
Does anyone compare 3255/3251 to UCD32MP?
In the case of MA12070, which is better, the board or the finished Sabaj product?
It's difficult to make a circuit. There is also deterioration in sound quality. So I buy a new board.
Does Hanzao3255 also have pop noise?
I want a board with excellent sound quality. Better than Shui Yuan TPA3255.
Does anyone compare 3255/3251 to UCD32MP?
In the case of MA12070, which is better, the board or the finished Sabaj product?
Hanzao's amplifier board has the same symptom for both TPA3255 and TPA3251.
I bought four MA12070 chip amplifier boards and experimented with them.
This amp board is also difficult to handle.
I have tried both balanced and unbalanced connections, but the balanced connection is stable, but the unbalanced connection has a habit, and depending on the DAC to be connected, the operation becomes unstable and noise is generated.
Like the Shui Yuan TPA3255 amp, this amp board can also eliminate pop noise when the power is turned on by adding a capacitor. There is no pop noise when the power is off.
I bought three SA300s as a completed amplifier product with the MA12070 chip. The operation of SA300 is very stable.
I also bought two new BRZ HiFi mini amps, which sounded good but didn't turn on the day they arrived. I also purchased a BRZ HiFI TPA3255 amplifier product, but it also did not turn on. There are risks associated with purchasing BRZ HiFi products.
The 3e audi product is the most stable of the TPA3255 amplifier boards I have purchased so far. I'm also very interested in JLE's products, but I haven't purchased them yet.
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GeekySimar
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Hi Guys,
I am setting up a new amplifier. I am in fix between Shui Yuan, 3E Audio and Hanzhao board. Can you guys please suggest, which one is the best out of three considering stability and audio quality.
Can you guys also suggest the power supply accordingly! The MeanWells are large, so looking for compact power supplies.
I am setting up a new amplifier. I am in fix between Shui Yuan, 3E Audio and Hanzhao board. Can you guys please suggest, which one is the best out of three considering stability and audio quality.
Can you guys also suggest the power supply accordingly! The MeanWells are large, so looking for compact power supplies.
Thanks for the detailed explanation.
I would like to buy a Sylph-D200.
Do you have the size and wiring diagram for this board?
Which is better, Output Inductor?
Please see the following HP for the data of Sylph-D200.
This product is a little expensive, but it is an amplifier that uses PFFB (post filter feedback type) and is of very high quality.
The designer of this product (jlesterp) participates in this ASR forum, so I think it is easy to get information. The company is in the Philippines. (Look at # 1,080 # 1,110!)
I've used a variety of Chinese Class D amp products, but it's time to get a slightly higher-end product.
https://www.jlelectronicsph.com/product/sylph-d200-tpa3255-pffb-stereo-ready-to-run-amplifier-module
Thanks for Tokusan.
I listened carefully to Shui Yuan TPA3255 and Hanzao 3251.
The power supply in the upper center of the photo is used.
Hanzao 3251 is great. Clear, deep and rich sounds.
Shui Yuan sounds brighter and more choppy.
Hanzao's big pop noise.I feel very bad about that.
I'm heading to JLE's.
I listened carefully to Shui Yuan TPA3255 and Hanzao 3251.
The power supply in the upper center of the photo is used.
Hanzao 3251 is great. Clear, deep and rich sounds.
Shui Yuan sounds brighter and more choppy.
Hanzao's big pop noise.I feel very bad about that.
I'm heading to JLE's.
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- Joined
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I would not buy the Hanzhao due to pop noise.
I bought the Shui Yuan a few montrh ago and I am quite happy with it. But I would not recommend it due to very cheep connectors which are just not nice to work with. The power and speaker connectors feel yery cheep and no not accept thick wire. I really could not build my amp as I wanted it to build. The Shui Yuan is just very small and very cheep.
The 3E Audio seems to be much more substantial. Its also more then twice the price of the Shui Yuan. 3E Audio is also active here on ASR and posts their own measurements.
I would for the 3E Audio or the JLE if you can affort it.
Hi there,
I have both the Shui Yuan and 3e Audio and I agree that the Shui Yuan is really very good for the money, and IMHO is better than the 3e Audio. The 3e is clean and detailed but is somewhat lacking in the bass. The sound-stage is slightly broader with the 3e audio but I prefer the transients produced by the Shui Yuan, which have greater impact when playing rock music.
In my system using a Thorens TT source with the 3e audio the bass gets wooly and uncontrolled on bass heavy tracks. Sometimes also the HF gets a bit too much too bear - perhaps more burn in time is needed? To be fair, this can also be attributed to other components in the chain, and particularly to my source, such as the arm or cart used.
However using the same setup I have no such issues with the Shui Yuan, although I have not played it too long for it to consider it burned in as yet (if there is such a thing with Class D amps). It has an overall warmer sound without compromising too much on detail. It is less refined than the 3e, but only marginally so. I'd surmise the 3e audio to be better with classical music and the Shui Yuan with rock/pop but having said that the Shui Yuan is no pushover when it comes to classical music either. In any event, I think a lot of experimenting needs to be done to attain the sound you want given the other components in the chain; with the right set up I think the 3e can be very good indeed, but perhaps not in mine.
I was tempted to try the Hanzhao but it could well be just a lateral move. A better option as suggested is to go a step up and try a JLE module, so I'm also looking forward to reviews and comments relating to the Sylph D-200 or even the 3251 version in comparison to a Shui Yuan or 3e 3255.
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