Hi Anatoliy
as i wrote in #974 a try on the YJ TPA3255 board and after modding its fine for me...
I do not know this amp..its based on the TPA3255 and has additionally Bluetooth. ...housing but no power supply..
what do you want to ask? compared with my board which i know i miss the dual opamps ....?
chris
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No luck with getting more loud via notebook, some about same level. Think the reason also can be 8hom impendance of rock solid b&w monitors rated 150W . I expected tpa3255 will blow them away since they rather sencitive, i tried them play directly from notebook audio pin and they played rather well. Can these monitors really handle 150w ?! I hear no distorion even at max level, just magic... Think main power belongs to lower end frequency they are just cut by crossover and play from 70Hz and up.
Interesting!
Is Allo upgrading the Volt series from a 3118 base to a 32XX series chip?
@ AnatoliyHill
I found the finished TPA3255 amplifier cheaper. Aliexpress TPA3255
I'm not sure if I should buy. I had an 36V powerbrick from my Indeed TDA7498E.
It would work but not at full power :-D
I found the finished TPA3255 amplifier cheaper. Aliexpress TPA3255
I'm not sure if I should buy. I had an 36V powerbrick from my Indeed TDA7498E.
It would work but not at full power :-D
Hansueli, I got same device you linked. Worth to try. Iam useing industrial dc1200W 50V/20A taken from GSM tower. Make sure you have enough dc converter. Btw recently bought Canton SC-L in mint condition and sound is getting about to appear. This tiny box tpa3255 controling these big towers rather well.
Hi, there. Just opened amp to enable see mates inside. For my experience this looks very budget friendly interpretation of original board. Even main capacitor rated 50V with no reserve for voltage. Im getting nervous since sorcing 50V dc. take a look guys and what are your advices for quick win improvement in my case. Have no precise problem with how it sounds but ...you know we are buying these things to keep on improveing.
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Hi Anatoliy
thanks for your pics. (use the smartphone at HDR mode to get sharp pics
)is it possible to dismount the heat sink and make a pic -we can compare to the other TPA3255 board
pic 1
in the first pic in the bottom there should be the the opamps. I miss the decoupling caps for the power of the op amps....
i read that the Bluetooth made a lot of his...how it is handled here at this amp? i see no switch to choose between bluetooth or RCA input?
is it possible to disconnect the bluetooth module? and compare with/or without bluethooth in soundwise
chris
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your SMPS should have a poti to adjust the Voltage setting...set it down and then connect it to the amp again.
Not sure dismount heatsink will safe procedure for me. Think thrte should be thermopast inbetween tpa body and sink which iam not in position to look for and put again. BT on device is connected by default just chous from device you are about listening phone/ ipad / xiaomi etc. If no BT connection it switch to rca input . The connection handled by relay , i suppose to due click sound during switching. BT is rsther silent , no audible hizzz. Some hizz within 5-10 cm from high frequency speaker with 90 db/1w/1m sencivity which is quite good for me. Previous board Tpa3116 was deadly silent but this device is ok. Will check if there is less hizz via rca against BT.
hi Anatolliy
the potentiometer i mentioned is an adjustable resistor - with a screw driver you can normaly adjust the output voltage of the smps in a ran of e.g. +- 4V
chris
Sound is not constant powerflow to be measureded conventional powermeter thus may be some deviation in measurement. Perhaps sinus signal 400 hz and its power measurement can deliver more realistic result, but be carefull: speakers are not dedicted to work on one frequency and can be damaged even 30% of din power depend on frequency. The one thing I understand dealing with tpa3116 via laptop 65w dc and tpa3255 via 1200w dc is that these tpas are extremely effecient and their power specifications shouldnt be compared with conventional ab transistors smplifiers with big transformers. Very universal to 4-8 hom speakers , high voltage rise V/ms delivering fast airy notes much easier
So true! The continuous power capability is depending on the frequency divider of a two or more ways speaker system.
OTOH, according to the related DIN 45500, the woofer has to cope with the rated power within it's frequency range for at least ten minutes without damage.
Best regards!
Hi, mates again. Still looking for more loud from the tpa3255. Cant say it is no too much loud but small edifier r2700 produce more bass than canton sc-l with my tpa3255. Consider rather small main capacitor cant produce enough peaks. What do you think? I see original board contrain two big capacitor, my have only one with 1000mF/50v noname CpXon .
The 3255 EVM has 2x 4700uF 100V
You should notice the bass lacking first if not enough. Type of supply and the thickness and length of the power cord to the board also come into play.
About you loudness problem: do you have a mixer of any kind or other device with a decent signal voltage to feed the board? My guess is that your audio device is not putting enough voltage into the board.
For who is interested in a board as good as the EVM and/or power supply/dsp board; the groupbuy (Group buy: TPA3251_TPA3255 Amplifier board and ADAU1701 DSP Pre-Amp board) needs just a few more people and will end soon.
You should notice the bass lacking first if not enough. Type of supply and the thickness and length of the power cord to the board also come into play.
About you loudness problem: do you have a mixer of any kind or other device with a decent signal voltage to feed the board? My guess is that your audio device is not putting enough voltage into the board.
For who is interested in a board as good as the EVM and/or power supply/dsp board; the groupbuy (Group buy: TPA3251_TPA3255 Amplifier board and ADAU1701 DSP Pre-Amp board) needs just a few more people and will end soon.