Actually no Class D amplifiers have terrible psrr. This is why best setups use low noise regulated PSU (like Astricons)
Those in-house boards don't have a mute switch solder point on them? I would love that as I have used up a bunch of switches on the same boards. Do u have sound comparison from in-house vs Sanwu?
Standalone Volt
We are working as we speak on the standalone TPA3118. Same as the picture (except it has RCA inputs)...with a little trick.
Remember when I said the class d amplifiers have bad psrr ? Not the stand alone...we can give about 70db of PSRR on the board.
That will have significant impact on sound.
We are working as we speak on the standalone TPA3118. Same as the picture (except it has RCA inputs)...with a little trick.
Remember when I said the class d amplifiers have bad psrr ? Not the stand alone...we can give about 70db of PSRR on the board.
That will have significant impact on sound.
Basically it will attenuate the noise and ripple from your PSU (and any laptop bricks have lots). That will give you better sound (clean power = clean sound)
Great! Sign me up. What do I do with the 6 or so 3118 Sanwu boards tho? Lol. I've noticed that wattage goes down considerably with stereo versions of 3118. Is this the case with "house" ones as well? Something like 60w for the mono and 25 for the stereo? I find I enjoy the full 60w of the mono boards for head room and max volume for the less than efficient small 3-4 inchers I am building.
In an earlier post (#1202) , you commented "Actually no Class D amplifiers have terrible psrr" ??
By the way, according to the data sheet, the typical 3116/3118 chip has a PSRR of -70 dB.
Regards,
Each chip has 2 channels. The mono boards simply route one input channel through both sides of the chip. One chip = 50-60W of output whether it be into one channel or two.
To get full 60w , you will need 24v and 4ohm speaker or something close to that
And not to mention distortion level at that wattage level
Currently I'm running
- 20V from laptop adapter
- 20db gain modified
- Visaton FR10 4ohm speaker in Buschhorn
- A cheap X-DA3 USB PCM5102A DAC without volume control(direct connect)
- Player is foobar2000 with standard EQ
I won't say its the loud setup, but it suit my requirement
The amp barely get hot
Hissing noise level was better than my previous amp running on TDA7294
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Yeah the graph is showing between 58-70db up to 10Khz.. we have better psrr even at higher frequency. Also both psrr will add up.
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Hi,
Just read about post filter feedback, do you think it can be implemented for tpa311x?
http://www.ti.com/lit/an/slaa702/slaa702.pdf
Just read about post filter feedback, do you think it can be implemented for tpa311x?
http://www.ti.com/lit/an/slaa702/slaa702.pdf
tpa3118 with capacitance multiplier
Attached is our Volt+ with capacitance multiplier .CM has a PSRR of about 70db up to 100Khz and about 48db at 1Mhz
It will work with any laptops bricks from 12-24v and dropout voltage can be adjusted using the trimpot (dropout voltage should be higher than noise/ripple on PSU) We recommend 2x higher to make sure its fine.
Attached is our Volt+ with capacitance multiplier .CM has a PSRR of about 70db up to 100Khz and about 48db at 1Mhz
It will work with any laptops bricks from 12-24v and dropout voltage can be adjusted using the trimpot (dropout voltage should be higher than noise/ripple on PSU) We recommend 2x higher to make sure its fine.
Attachments
Sorry but layout is very impractical. How is this board supposed to be built in a case ?
- Input connectors are at the same side as volume potentiometer ?!
- speaker connectors are at the opposite side of DC jack ?!
- power on LED is at the same side as the DC jack ?!
Please think of a better layout so that devices can be encased without headaches. Volume and power on LED are at the front. Speaker outputs, DC jack and RCA inputs are at the backside in 99.9% of devices that are meant to be operated by humans.
- Input connectors are at the same side as volume potentiometer ?!
- speaker connectors are at the opposite side of DC jack ?!
- power on LED is at the same side as the DC jack ?!
Please think of a better layout so that devices can be encased without headaches. Volume and power on LED are at the front. Speaker outputs, DC jack and RCA inputs are at the backside in 99.9% of devices that are meant to be operated by humans.
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Hi Jean Paul ,
yeah we are aware of RCA/potentimeter , but from our testing it should have enough space.
Speaker connectors /dc jack...that was our choice since the beginning. We wanted to separate the digital noise from analog stage as much as possible
We will release a very cheap acrylic box for it.
yeah we are aware of RCA/potentimeter , but from our testing it should have enough space.
Speaker connectors /dc jack...that was our choice since the beginning. We wanted to separate the digital noise from analog stage as much as possible
We will release a very cheap acrylic box for it.
It has the same ergonomics as Raspberry Pi. It would be wise to design not only with technical excellence in mind. A device should be ergonomically unchallenged otherwise it will annoy all its users all day every day !
Connectors at three sides ?! What where you guy thinking ? The now created cable salad/spaghetti is very annoying as it takes more space than necessary and it gives a messy look. Besides that it serves absolutely no purpose.
Connectors at three sides ?! What where you guy thinking ? The now created cable salad/spaghetti is very annoying as it takes more space than necessary and it gives a messy look. Besides that it serves absolutely no purpose.
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No LDOs...its only a CM that will track whatever voltage comes in..(- dropout voltage about 0.6v with noisy PSU)
Plot for CM will be available soon
Plot for CM will be available soon