Do you have any of these problems while listening music / real world use?
Burn protection worked thankfully.
I would never let a heat sink get that hot, better use a fan if you want to enjoy the chip and/or the components around it for some time.
Put a pillow or blanket over it to pass the burn test.
Burn protection worked thankfully.
I would never let a heat sink get that hot, better use a fan if you want to enjoy the chip and/or the components around it for some time.
Put a pillow or blanket over it to pass the burn test.
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Do you have any of these problems while listening music / real world use?
Burn protection worked thankfully.
I would never let a heat sink get that hot, better use a fan if you want to enjoy the chip and/or the components around it for some time.
Put a pillow or blanket over it to pass the burn test.
Hi think
No actually i had just time to play in the lab...no listening sessions. my psu 24/4A is to weak to push more.
amp vs psu....1:0...i have to wait for my meanwell 350-36...
As you can see i did one stress test but nothing special....what happend exactly?
chris
As it is heat and not power which destroys electronics, I'm wondering what you are really testing and what for.
I used to overclock computers in the early days and learned that prolonged heat and big temperature changes, degenerates or even destroys chips and other components a lot faster. If heat-sinks are to hot to touch it's generally a good idea to add some sort of cooling; the chip underneath it is already a lot hotter.
Other thing I wonder; Why would you fix a 'problem' which you will never encounter in real world use, especially if you are going to be the knowledgeable and responsible user; better enjoy it's great sound before you can't even listen to it anymore.
I know how I can get caught up in perfectionism, but I now ask myself the following question with many things I encounter; does it have any impact in the real world / on our lives? If not, why would I put more effort/energy in it?
I.e. Do aliens exit? As long as there are no traces of them in the real world, and thus wont impact our lives, why would I discuss this subject any more?
If you really enjoy it, keep doing it, but otherwise there is probably something else you can enjoy more.
Enjoy!
I used to overclock computers in the early days and learned that prolonged heat and big temperature changes, degenerates or even destroys chips and other components a lot faster. If heat-sinks are to hot to touch it's generally a good idea to add some sort of cooling; the chip underneath it is already a lot hotter.
Other thing I wonder; Why would you fix a 'problem' which you will never encounter in real world use, especially if you are going to be the knowledgeable and responsible user; better enjoy it's great sound before you can't even listen to it anymore.
I know how I can get caught up in perfectionism, but I now ask myself the following question with many things I encounter; does it have any impact in the real world / on our lives? If not, why would I put more effort/energy in it?
I.e. Do aliens exit? As long as there are no traces of them in the real world, and thus wont impact our lives, why would I discuss this subject any more?
If you really enjoy it, keep doing it, but otherwise there is probably something else you can enjoy more.
Enjoy!
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hi think
i can follow what you mean.
..i am interessting in "what is real possible or not" ...so i really do not care what is written in the chinese board commercials.... i try to "back engineering" that what i learnt hear and what i know. i want to share this. as we all know here is that the lab with some test condition are partly (resitive load or complex...)harder than the real world of playing music over speakers. yes it is the result of "knowing" that this kind of power is the max of that board. (40min test => over 100°C) about 65WAtt each channel.to fix this problem is just to know and not discussing what can be or should be. its a matter of fact or not. so i investigate time to try to solve this. What is the reason that the other board is working and this not??? -realy just the old caps??? for me its important to have experience for repare older amps or trouble shooting.
it is not a kind of perfectionismus. its a kind of completness as near as i and all members of this forum to help me or not to go forward. i do not want to blaim a company or person. its just a mix of personal interest and things which you get from some vendors. its everybodies decision to buy and test what every they want. i personally dont belive ...i want to try my best to "know" it.
back to this board amp2 : its "burn in" at 300mV since approx 40 hours continiously. about 5.5 -7.5 V and 1,2 -1,6 A (DMM) with a swepp of 10khz -25kHZ.
i want to have no excusses for the caps --> not ready to do the same as the others. so if the elna caps are old and faulty the next step is to decide what happend....sounds good...ok ...but what sounds better
chris
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Hi Chris,
Your energy and progress speed is absolutely impressive. But, it can be difficult to follow your exact experiment because it is sometimes described over more pages of elaborate postings.
With my limited understanding of your problem, could the cause be the following? You start the amplifier near the clipping level (which is an unusual use of an amplifier). During start-up, you have current transients (as usual) that are not present during steady-state operation. The start-up transients surpass the over-current limit and the fault is latched by the protection circuit. Then you have a shut-down.
If your ELNAs are decoupling capacitors, the better they are the more transient current you can draw. They may not be faulty at all, on the contrary.
Sorry if I may have disturbed good experiments with irrelevant non-sense.
Your energy and progress speed is absolutely impressive. But, it can be difficult to follow your exact experiment because it is sometimes described over more pages of elaborate postings.
With my limited understanding of your problem, could the cause be the following? You start the amplifier near the clipping level (which is an unusual use of an amplifier). During start-up, you have current transients (as usual) that are not present during steady-state operation. The start-up transients surpass the over-current limit and the fault is latched by the protection circuit. Then you have a shut-down.
If your ELNAs are decoupling capacitors, the better they are the more transient current you can draw. They may not be faulty at all, on the contrary.
Sorry if I may have disturbed good experiments with irrelevant non-sense.
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Hi FF
thanks for the roses...."impressive"
..i do not watching TV since 9 month so i start at 7PM untill 10PM...if it is possible and i am not so tired....so its time to do some audio.i am really in falme for audio...after 3 decades of doing stupid audio things
now i do something...yes i agree the 700mVrms is a nonsense setup at start...but as i wrote why is the other board (amp1 )handle this and the ELNA board (AMP2) not?. but it is happened for 300mVrms or 400mVrms too !!
this days the "burn in" will be finisehd and then i feed you with sound informations
chris
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Recently, I discussed with another member who has a TAS5630 based amplifier. It would shut down only the right channel at high levels. We found that it was the over-current protection on the right channel that was invoked. With better filter chokes on the right channel only, both channels could play much louder. This to say that the over-current limitation in practice can react very differently. And, on top of that you have different decoupling capacitors.
30 years ago I would have hired you in my team. Now, it's no longer feasible. Too much television only makes you stupid, but make sure you get enough sleep and spend time with your family as well.
30 years ago I would have hired you in my team. Now, it's no longer feasible. Too much television only makes you stupid, but make sure you get enough sleep and spend time with your family as well.
thanks for your experience. step by step i go forward.
Ah..... you did this professional?
yes i do not spend all of my time to my hobbies, yes my familie is priortiy 1. But kids (14 +10) are in some kind of situation more easier to handle
.
hi again
After the long periode do nothing with audio...
i still have 2 amps modified. to go ahead with SQ check i kept the original caps (elna 3900µF/100V) at amp2 to find out if this long stored caps are working.
both amps connected to my new LRS 350-36V psu so power should be not a problem. As discribed on page 24 i still have some "technical" issues but later more...
to start the amp is use the mute switch and compare the 2 amp board:
both amps are running the last days in my lab for 50hours with my sweep 10Hz-25khz and 300mV input voltage -> 51°C all over the time...power about 10-16watt.
the amp1 the nichicon version (input 10µand big 3300µ caps) sounds fine and in comparison to the amp2 elna + silmic2 10µ at the inputs is slightly more on the analythical side. i compared these 2 boards several times on 4 different days.
result :
the original caps could stay in the board. maybe with very good caps with very low ESR i get some different. we will see/hear
elna 3900/100V 105°C
Nichicon UFW1H332MHD
ESR to high?
shut down of the AMP´s: ??
at more level at some bass titles e.g. vaun - listen i got at more volume level as the 24v psu from the Fx502Spro more power and a better darkness...but...still a shut down of the amp = fault LED goes off...both or one channle (L) goes down. mostly both channels !! 2x 3300µ/50V directly on the boards supply terminals doesn´t help to solve this issue. the psu is still happy and on....i do not think that i get run out of power with the new LRS 350-36V.
so the difference in dynamic titles - still made this board "strange"
sorry but i am not ready to show you some measurements. LRS350-36V is directly connected- without inrush current limiter to 230V - the cables to the amp are about 50cm long.
ideas?
chris
After the long periode do nothing with audio...
i still have 2 amps modified. to go ahead with SQ check i kept the original caps (elna 3900µF/100V) at amp2 to find out if this long stored caps are working.
both amps connected to my new LRS 350-36V psu so power should be not a problem. As discribed on page 24 i still have some "technical" issues but later more...
to start the amp is use the mute switch and compare the 2 amp board:
both amps are running the last days in my lab for 50hours with my sweep 10Hz-25khz and 300mV input voltage -> 51°C all over the time...power about 10-16watt.
the amp1 the nichicon version (input 10µand big 3300µ caps) sounds fine and in comparison to the amp2 elna + silmic2 10µ at the inputs is slightly more on the analythical side. i compared these 2 boards several times on 4 different days.
result :
the original caps could stay in the board. maybe with very good caps with very low ESR i get some different. we will see/hear
elna 3900/100V 105°C
Nichicon UFW1H332MHD
ESR to high?
shut down of the AMP´s: ??
at more level at some bass titles e.g. vaun - listen i got at more volume level as the 24v psu from the Fx502Spro more power and a better darkness...but...still a shut down of the amp = fault LED goes off...both or one channle (L) goes down. mostly both channels !! 2x 3300µ/50V directly on the boards supply terminals doesn´t help to solve this issue. the psu is still happy and on....i do not think that i get run out of power with the new LRS 350-36V.
so the difference in dynamic titles - still made this board "strange"
sorry but i am not ready to show you some measurements. LRS350-36V is directly connected- without inrush current limiter to 230V - the cables to the amp are about 50cm long.
ideas?
chris
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i try now in the evening 3 times following:
DMM on the amps terminal...scope is actual not available.
DMM shows DMM 36,03V...ok i add my best low ESR i found...1000µF/50V nichicon UHE1H102MHD6..... 2 directly at the amp supply terminal and 2 directly at the psu terminal (meanwell LRS 350-36)
if i push the title PANDA by Desiigner...at second 40-42 the DMM shows 36,18 or slightly more...so the voltage goes up !!! then the amps shuts down...fault is off --> at this board...so fault is on if i switch the mute ..2 seconds volume down...the amps is working fine.
psu is up and running green LED is on...no hick up mode...fine..
more tests at this time is not allowed....
DMM on the amps terminal...scope is actual not available.
DMM shows DMM 36,03V...ok i add my best low ESR i found...1000µF/50V nichicon UHE1H102MHD6..... 2 directly at the amp supply terminal and 2 directly at the psu terminal (meanwell LRS 350-36)
if i push the title PANDA by Desiigner...at second 40-42 the DMM shows 36,18 or slightly more...so the voltage goes up !!! then the amps shuts down...fault is off --> at this board...so fault is on if i switch the mute ..2 seconds volume down...the amps is working fine.
psu is up and running green LED is on...no hick up mode...fine..
more tests at this time is not allowed....
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the values 16,3Amps is wrong its the TPA3251....for TPA3255 its 17Ampere
i will check the resitor values with DMM...maybe its not CB3C...its Latched OC...or wrong values.
Hello,
I need your advice ...
1. Is it possible to use this amp version with 8 ohm load and 51-52 V DC supply ?? ( when LM2575 is replaced to HVS version .... ) ...
2. Is it a bad idea to use external heatsink mounted on the amp case and connected to TPA3255 top termal pad ??? ( any problems with that idea ??? ) .
Best regards,
Emil
I need your advice ...
1. Is it possible to use this amp version with 8 ohm load and 51-52 V DC supply ?? ( when LM2575 is replaced to HVS version .... ) ...
2. Is it a bad idea to use external heatsink mounted on the amp case and connected to TPA3255 top termal pad ??? ( any problems with that idea ??? ) .
Best regards,
Emil
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thx doctor
so i interpret this that the smps is on its max? (36V/9,7amp max power)?
No, it just regulates output voltage all the time as a function of output current to vary the duty cycle. Pulling high current and then drop to nearly zero introduces an overshoot in regulation loop which you see as increased voltage. Additional capacitance doenst make things better it just slows down the regulation loop. Some 1000uF won't help to stiffen anything here as frequency is much higher than on traditional 100/120Hz toroid supply.
Hi emil
1 yes it should be possible. but xcheck the datasheet and compare to the chinese implementation.
2 as i read from the developers here its important to made the contact to the chip as perfect as possible = ideal a mirror surfaced buttom side of the heat sink to get away the heat from the TPA chip itself + the contact to the pcb. i think the plastic washer should be changed to aluminium washer. if you dismount the supply terminals you can try to install a little bigger heatsink. the chip is protecting itself - OTE - if its getting too hot...etc..
in my home use the 36V (LM2575S max 40V) is enough power for living rooms
i check a completely non modified board and compare it with my two amps. my suggestion is = change the input caps (10µ/16V) this is the only part you should invest.
and implemt the "mute switch"...as the low budget step of modifypage 68 #679 in:
TPA3255 - all about DIY, Discussion, Design etc.
chris
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Ah...ok...this is what i found - with or wihtout caps = no changes.
if i get back my scope i will check the input and output voltage if this event happend.
my calculation is 36V/ and 4 ohms from KEFQ100 is max current = 9 amps so its nearly on the boarder. but i do not think that i push 350 into 2 speakers...
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