I found the reason for the bad sound, replaced the opamp with the old LM833. There was volume, depth, air, standard 5532 is definitely a fake.
I found the reason for the bad sound, replaced the opamp with the old LM833. There was volume, depth, air, standard 5532 is definitely a fake.
It seems you can measure =) Can you give a try with some OPA1656 or Genuine 5532 and keep us posted ?
At what power was the measurement?
On the graph, -20 dB.
I have a THD of 0.2% at low power (less than 0.1 W)..
The noise is -60dB.
On the graph, -20 dB.
I have a THD of 0.2% at low power (less than 0.1 W)..
The noise is -60dB.
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To Polevka
Hey!
THD measurement at 10 watts RMS into 8 ohm load.
The noise level is about 100 dB.
P.S. The filter calculation is available on the TI website.
Hey!
THD measurement at 10 watts RMS into 8 ohm load.
The noise level is about 100 dB.
P.S. The filter calculation is available on the TI website.
I have an HF driver - 8 ohms.
LF and MF - 16 ... 🙂 How do I calculate the inductance of a coil?
The Ti website only has a calculation for 8 ohms.
LF and MF - 16 ... 🙂 How do I calculate the inductance of a coil?
The Ti website only has a calculation for 8 ohms.
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Sorry to change the subject. Any recommended Op amp upgrade for the 3e Audio 3250 amp? Audio science shows replacing the OPA 1602 with the cheaper LM4562 improves measurements.
3e Audio SY-DAP2002 Review (DSP Amplifier) | Audio Science Review (ASR) Forum
I'm not looking for better measurements, just a better sound. Can an Op amps tone down the upper mids?. BTW I've tried using the onboard DSP with the 3e Audio USBi cable, but unable to save to EEPROM board. An external DSP would have been better.
3e Audio SY-DAP2002 Review (DSP Amplifier) | Audio Science Review (ASR) Forum
I'm not looking for better measurements, just a better sound. Can an Op amps tone down the upper mids?. BTW I've tried using the onboard DSP with the 3e Audio USBi cable, but unable to save to EEPROM board. An external DSP would have been better.
Has anyone used one of the 4-channel TPA325x alternatives ? I'm considering them for active speakers (2 drivers per cabinet) so interested in feedback & advice
ShuiYuan (?) TPA3251 o Amplifier Board 4X100W Hight Power 4 Channel Cl D o Amplifier Board Module|Operational Amplifier Chips| - AliExpress
3EAudio TPA3251-4CH-100W | 3e Audio
Lyele (?) TPA3255 power amplifier board four channel digital class D high power power amplifier board 300W*4|Amplifier| - AliExpress
TPA3251/TPA3255 digital audio amplifier board 1/2/4 channel 135W/175W/315W/600W power amplifier board|Amplifier| - AliExpress
Unknown Brand TPA3255 Sound Amplifier Board 315W 4 Channel Digital Class D Power Amplificador NEW 2020|Operational Amplifier Chips| - AliExpress
All seem to have surface mounted OpAmps and other aspects vary (one includes fans)
Is there any real advantage to using a single 4-channel board vs. 2 dual channel boards eg. related to power supply
ShuiYuan (?) TPA3251 o Amplifier Board 4X100W Hight Power 4 Channel Cl D o Amplifier Board Module|Operational Amplifier Chips| - AliExpress
3EAudio TPA3251-4CH-100W | 3e Audio
Lyele (?) TPA3255 power amplifier board four channel digital class D high power power amplifier board 300W*4|Amplifier| - AliExpress
TPA3251/TPA3255 digital audio amplifier board 1/2/4 channel 135W/175W/315W/600W power amplifier board|Amplifier| - AliExpress
Unknown Brand TPA3255 Sound Amplifier Board 315W 4 Channel Digital Class D Power Amplificador NEW 2020|Operational Amplifier Chips| - AliExpress
All seem to have surface mounted OpAmps and other aspects vary (one includes fans)
Is there any real advantage to using a single 4-channel board vs. 2 dual channel boards eg. related to power supply
I use this one.Is there any real advantage to using a single 4-channel board vs. 2 dual channel boards eg. related to power supply
The difference in the price / quality ratio.
You get 4 BTL channels for the price of two.
But, I immediately replaced the TL 071.
It is possible to switch to 1PBTL + 2BTL mode.
I have three speakers in each speaker. I connect the PBTL channel at the low frequency, and at the midrange and high frequencies through the BTL channel.
It is not recommended to use a power supply with a voltage higher than 36 volts.
On your first link, a similar amplifier, only on TPA 3251
It will heat up less because it has a better radiator.
The rest I don't know, newer developments.
The only real advantage is the price.
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To Polevka
Hey!
THD measurement at 10 watts RMS into 8 ohm load.
The noise level is about 100 dB.
P.S. The filter calculation is available on the TI website.
I tried to recalculate the filter so that the frequency response does not fall over to the high frequency when the driver resistance is 8 ohms. It turned out that the filter frequency should be 90 kHz. for 10uH coil.
Or change the inductor.
Attachments
To Polevka.
You need to reduce inductance or capacitance, those that are 1 μF I think 1, 41 times.
You need to reduce inductance or capacitance, those that are 1 μF I think 1, 41 times.
Sorry, it is better to increase the inductance by 2 times, and reduce the capacitance by 2 times. Cutoff frequency 40 kHz.
This is clear. Didn't want to change inductance ...
To increase the inductance means to buy another one and wait for it to arrive - a month or more. This is not an option.
It is not clear why ULFs are designed for a load of 4 Ohms?
Does everyone have car speakers in their acoustics? 🙂
My speakers have 16 Ohm drivers for LF and MF.
P.S. I'll leave it as it is for now. I will equalize with an equalizer ...
To increase the inductance means to buy another one and wait for it to arrive - a month or more. This is not an option.
It is not clear why ULFs are designed for a load of 4 Ohms?
Does everyone have car speakers in their acoustics? 🙂
My speakers have 16 Ohm drivers for LF and MF.
P.S. I'll leave it as it is for now. I will equalize with an equalizer ...
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Has anyone used one of the 4-channel TPA325x alternatives ? I'm considering them for active speakers (2 drivers per cabinet) so interested in feedback & advice
[...]
Is there any real advantage to using a single 4-channel board vs. 2 dual channel boards eg. related to power supply
There is a DIS-advantage to using the 4-channel boards: the heatsinks are too small. Even with the 4ch board designed by 3e-audio, he cautions against using the full TPA3251 rail voltage with 4 Ohm loads. It's because too much heat will be generated, especially if the amp board is enclosed in a box without forced air (fan) cooling added.
I have a 4-ch TPA3255 board and I am thinking of making an aluminum spacer block to replace the existing heatsink. I can then mount the board via the spacer block to a larger heatsinnk.
As long as the PCB traces can handle the necessary current flow, there is nothing technically wrong with these 4-ch boards. Well, as long as they are designed correctly and the layout is good. But it is difficult to know that without buying and measuring one!
This is clear. Didn't want to change inductance ...
To increase the inductance means to buy another one and wait for it to arrive - a month or more. This is not an option.
It is not clear why ULFs are designed for a load of 4 Ohms?
Does everyone have car speakers in their acoustics? 🙂
My speakers have 16 Ohm drivers for LF and MF.
P.S. I'll leave it as it is for now. I will equalize with an equalizer ...
Try to make feedback from the filter output -PFFB . The effect of the filter will decrease.
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Hinged installation of elements?To Polevka
Try to make feedback from the filter output -PFFB . The effect of the filter will decrease.
Which option?
There are several of them ...
There are slaa702 and slaa788a (pdf)
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Thanks!
By the way. I found one of the options for dealing with The pop noise ...
Cheap and cheerful ... 🙂
By the way. I found one of the options for dealing with The pop noise ...
Cheap and cheerful ... 🙂
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Thanks!
By the way. I found one of the options for dealing with The pop noise ...
Cheap and cheerful ... 🙂
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