The power-supply depends on what max output you want. At 48 V 6.5 amps is not enough for the possible output at that voltage 128W at 8 ohms is 4 amps per channel , and if your speakers are lower say 4 ohms then 121W are 5.5 amps per channel , for example.
in this case you need about 48 volts for 8 ohm loads and about 38 volts for 4 ohm loads .
The power-supply must be able to feed both channel simultaneously. SMPS must be able to supply 8 amps rms ! for two channels at 8 ohms and 12 amps for 4 ohms , otherwise they might shut down due to overload or the output voltage dip in case of strong transients
in this case you need about 48 volts for 8 ohm loads and about 38 volts for 4 ohm loads .
The power-supply must be able to feed both channel simultaneously. SMPS must be able to supply 8 amps rms ! for two channels at 8 ohms and 12 amps for 4 ohms , otherwise they might shut down due to overload or the output voltage dip in case of strong transients
Hi,
I'm using 48v 3ampere adapter with TPA3255. I don't think I need more ampere for my usage. As I'm using 8ohm speakers , I never had the amp shutdown on me yet even on very high volume.
My theory on this is the capacitor act as a reservoir during the peak transient.
Perhaps 4ohm load will need bigger capacitor or higher ampere adapter . For 8ohm speaker ...It's more than enough for home use
I'm using 48v 3ampere adapter with TPA3255. I don't think I need more ampere for my usage. As I'm using 8ohm speakers , I never had the amp shutdown on me yet even on very high volume.
My theory on this is the capacitor act as a reservoir during the peak transient.
Perhaps 4ohm load will need bigger capacitor or higher ampere adapter . For 8ohm speaker ...It's more than enough for home use
oops, I got the wrong link ... I was thinking about this one. Amplificateur Audio numerique, alimentation de commutation, HiFi PSU, 350W 24V 27V 32V 36V 42V 48V 54V 60V | AliExpress
I did a quick edit with a smaller transformer even if the sound is correct, when I exceed half the power the sound does not go up, certainly because of the lack of ampere
I did a quick edit with a smaller transformer even if the sound is correct, when I exceed half the power the sound does not go up, certainly because of the lack of ampere
I always calculate and build my power-supplies for the worst possible condition , that is max output sine wave sustained continuously .
The reason : An "underfed" amp tends to clipping easily and often unnoticed which effectively makes it a speaker-killer. Because when it clips it puts out pure D.C.
Say you have a bass note driving the amp to within a few percent of clipping level and then a high frequency note either for the tweeter or the midrange. The bass note will go through unclipped but the high frequency one riding on top of it will be clipped until the bass note dissapears , Result : D.C. to the tweeter and /or the midrange. Slowly cooking then burning their voice-coils. ..............................
I have seen far too many burnt voice-coils from all sorts of speakers , even 50mm-diameter ones and up from woofers , all of them due to clipping amps .
ANY amplifier can go into clipping for two reasons :
1.) because a too high input signal is overdriving it .
2.) because a too weak power-supply starves an otherwise more capable amp and does not give it what it needs .
The result is the same in both cases and the second one can easily be avoided It is up to each of us which recipe to use.
I prefer to invest my money in a decent PSU rather than in replacement speakers. The ShuiYuan is capable of a lot of power. When using it for lesser power speakers one can make sure of having an excellent headroom for transients , then limit the max power with a potentiometer at the inputs to adapt it to the rest of ones equipment , and even measure the potentiometer once adjusted and substitute low noise resistors for it. And have a PSU normally working at low levels , so not stressed at all. It will last longer that way and be more secure..............................so yes , enough is enough but that does not mean its good .
The reason : An "underfed" amp tends to clipping easily and often unnoticed which effectively makes it a speaker-killer. Because when it clips it puts out pure D.C.
Say you have a bass note driving the amp to within a few percent of clipping level and then a high frequency note either for the tweeter or the midrange. The bass note will go through unclipped but the high frequency one riding on top of it will be clipped until the bass note dissapears , Result : D.C. to the tweeter and /or the midrange. Slowly cooking then burning their voice-coils. ..............................
I have seen far too many burnt voice-coils from all sorts of speakers , even 50mm-diameter ones and up from woofers , all of them due to clipping amps .
ANY amplifier can go into clipping for two reasons :
1.) because a too high input signal is overdriving it .
2.) because a too weak power-supply starves an otherwise more capable amp and does not give it what it needs .
The result is the same in both cases and the second one can easily be avoided It is up to each of us which recipe to use.
I prefer to invest my money in a decent PSU rather than in replacement speakers. The ShuiYuan is capable of a lot of power. When using it for lesser power speakers one can make sure of having an excellent headroom for transients , then limit the max power with a potentiometer at the inputs to adapt it to the rest of ones equipment , and even measure the potentiometer once adjusted and substitute low noise resistors for it. And have a PSU normally working at low levels , so not stressed at all. It will last longer that way and be more secure..............................so yes , enough is enough but that does not mean its good .
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Thanks Mike for your answer.
and when it comes to op amps someone would have another choice ...
is the OPA 1656 less suitable?
and when it comes to op amps someone would have another choice ...
is the OPA 1656 less suitable?
The opa 1656 is a very good op-amp which comes in a 8pin SOIC package and so is meant for smd mounting . of course it can be used in Dil-8 sockets but you have to use an adapter for this. Solder the chip to the adapter then you can plug it in. Wether you like its "musicality" only you can decide.
Did somebody solved idle noise? I have 3 modules, all are the same, more noisy than an AV receiver. Noise can be heard from the mid-range and tweeter 1m away, regardless if there is input connected or completely disconnected. I tried LM4562NA, but it did not have any effect. PSU Meanwell RSP-320-48, mostly set to 37-38V, but voltage also does not matter.
shortcircuit the input pins . These modules are quite silent so if inputs shorted the noise might come from the PSU
OPA1656 and 1692 are safe value OP amps.
The 1656 has a fabulous soundstage and it is very linear, this a kind of "all around" OP amp. The 1692 is more in the front of the stage, with amazing transcription of high notes
I made a video of my HanZao TPA3255 + OPA1692 here :
HanZao TPA3255 OPA1692 B
The 1656 has a fabulous soundstage and it is very linear, this a kind of "all around" OP amp. The 1692 is more in the front of the stage, with amazing transcription of high notes
I made a video of my HanZao TPA3255 + OPA1692 here :
HanZao TPA3255 OPA1692 B
You can add Ferrites in the signal path, this is well explained in the "cooKbook" from NewClass D and works great.
I do this with many of my amps and helps a lot :
Example with my TPA3255 / TPA3251 / Hypex Ncore :
Ferrits in the signal path cannot help. It is noisy even without signal cables at all.
I have just tried shortcircuiting the input pins, no difference. I tried moving PSU 2m away, no change.
I have just tried shortcircuiting the input pins, no difference. I tried moving PSU 2m away, no change.
The OPA1656 is great regarding the Soundstage. )
It has an excellent ratio performance / price but keep in mind you need a SOIC8 > DIP8 adapter and solid skills to solder )
It has an excellent ratio performance / price but keep in mind you need a SOIC8 > DIP8 adapter and solid skills to solder )
😀Thank you . Soldering is no problem have done it professionally for 50 years from the first Black and White Tv´s all the way through to repairing 4-layer PC-pcb´s......................🙂
I looked for a solution and if you also think about using modules for active speakers (and even more active bookshelf speakers) then decreasing midrange and tweeter sensitivity is probably necessary i.e. L-Pad is the way (DSP + ClassD ~ Hypex Alternative?)
I tried modules initially with old Aiwa speakers and was happy. Problem is with sensitive drivers (I have here RS52AN), it is too noisy.
XORCZ , your speakers are of normal sensitivity , mine are 3dB more sensitive and I have no hiss in them , only silence , unless I stick my ear into the tweeter that is !!! , and using the ShuiYuan with LM4562 for the time being , so check on the PSU . moving it away does´t help if you have high frequency ripple on the rail. Check with an oscilloscope if that might be the case. Class D amps switch to rails and if the rail is modulated with a high frequency ripple that can get through to the speakers because succesive switching impulses are then referred to a fluctuating rail voltage .
Check the output of your amp as well , using an oscilloscope. Besides you said you have the problem with three boards so that is an indication the problem is elsewhere too.
Check the output of your amp as well , using an oscilloscope. Besides you said you have the problem with three boards so that is an indication the problem is elsewhere too.
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MalleMike thanks, what you say is logic. I tried again, I can hear the hiss more from the tweeter (AMT2-4) than midrange. I connected the osciloscope to PSU output and pressed AUTO several times. I guess it is ok, because it is in mV range?
I was maybe expecting too much from the very cheap device.
I was maybe expecting too much from the very cheap device.
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Looks allright to me , yes . What about the output of the ShuiYuan ? Set the scope to as high as possible sensitivity but without passing the screen-limits and the time-base for 5 KHz.
Is the hiss aconstant one , does it have any "quality" to it , sound similar to something else ? Fluctuate at all ? You have very good tweeters there which likely go way up into ultrasonics
Another point : Class D amps react to the speakers impedance . Try to connect a 4 ohm resistor in series with the tweeters see what happens The impedance of "normal" tweeters rises with frequency , the one of yours does not !! If so you might want to compensate in the filters of your speakers , or adapt the output filters of the ShuiYuan to match your speakers
Is the hiss aconstant one , does it have any "quality" to it , sound similar to something else ? Fluctuate at all ? You have very good tweeters there which likely go way up into ultrasonics
Another point : Class D amps react to the speakers impedance . Try to connect a 4 ohm resistor in series with the tweeters see what happens The impedance of "normal" tweeters rises with frequency , the one of yours does not !! If so you might want to compensate in the filters of your speakers , or adapt the output filters of the ShuiYuan to match your speakers
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My intention was to do all filtering in the CamillaDSP. Normally I have these speakers connected to Pioneer VSX-924 and there is no noise. Just in case I touch the tweeter with my ear directly. Vs Shui Yuan I hear noise at 1m.
The only filter on the tweeter is 33uF protection cap. I do not have skills to modify modules. I put modules in the box, soldered connectors, modified PSU to noiseless 12cm fan (can recommend ARCTIC P12 Silent 120mm, starts always and no noise at all).
Measurement at idle, no input, the same with and without speaker connected. I do not think there is something wrong, I am just too close to speakers.
The only filter on the tweeter is 33uF protection cap. I do not have skills to modify modules. I put modules in the box, soldered connectors, modified PSU to noiseless 12cm fan (can recommend ARCTIC P12 Silent 120mm, starts always and no noise at all).
Measurement at idle, no input, the same with and without speaker connected. I do not think there is something wrong, I am just too close to speakers.
