Really? 🤣
Then, you should not make blanket statements that amplifiers with single rail power supplies have many defects. You should be able to name a few from those “many”.
Pointing someone to use Baidu (this censored source is used in China only) or Google instead of supporting your claim with soma facts is funny. I could claim that all D class amplifiers are utter crap and that nobody should use them. If somebody doesn’t agree, I will direct him to use Google.
Using car analogy in audio forum, instead of proper circuit properties, is more than funny.
I give an example.
For example, lm3886. This is a power amplifier that most people know.
Scheme 1: use +30v, GND, -30v power supply. Use one lm3886 chip.
Scheme 2: use +30v, GND power supply. Two lm3886 chip btls are used.BTL
Which plan do you think has higher cost and better effect.
There is no need to use different types for comparison.
Their power is the same.
I can't understand why anyone likes single power amplifiers.
Maybe it's because it can buy cheap charger power supply? This will be lighter. Not too much postage?
Few people use it like this in China. Because transformers are cheap. For example, an ac24-0-24 200va transformer. About 20 dollars.
This is fm115 and Jeff Rowland。
Now BBS has become a place for businesses to advertise.
Lose the meaning of discussion. I seldom come to BBS.
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（I could claim that all D class amplifiers are utter crap and that nobody should use them. If somebody doesn’t agree,）
Although I am also selling class D amplifiers.
But I agree with that.
Because I don't use class D amplifier myself. Because I have done experiments. I found EMI electromagnetic radiation at a distance of 3 meters. I'm a little worried that it will be bad for my health. I use analog amplifier myself.
But maybe it doesn't hurt. Although these radiation can be seen on the instrument.
But this is not what we are talking about. I don't even know why I'm talking about single power. ha-ha.
Infineon’s claim to the “digital” Class D amp?
“The MA12070 features an embedded digital power management scheme. The power management algorithm dynamically adjusts switching frequency and modulation to optimize power loss and EMI across the output power range.”
“The MA12070 features an embedded digital power management scheme. The power management algorithm dynamically adjusts switching frequency and modulation to optimize power loss and EMI across the output power range.”
Low voltage. Low power class D amplifier doesn't have much advantage.
Class D amplifier compared to analog amplifier. Its only advantage is efficiency. Efficiency of PWM.
But the voltage is low. Low power class D amplifier has no advantages
For example, tda2005 analog amplifier. Also use DC 20V. Make a complete amplifier.
Nor more than $2. And there is no EMI
Its effect is better than that of class D amplifier.
Try making a decent class AB running directly from a 3.6 V cellphone battery.
Class D in BTL can generate useful output power in that scenario.
I agree though that controlling the EMI is not trivial
Class D in BTL can generate useful output power in that scenario.
I agree though that controlling the EMI is not trivial
I copied iraudamp7s. But I changed it into a double-sided PCB.
Jumpers may not be used. I think it's simpler.
Iraudamp7s PCB design drawings are provided by Infineon. All components also have detailed values.
DIY is very easy. About $40. I named it l15dx2. To avoid the same product name as Infineon.
I have compared its effect Better than Jeff Rowland 250
Because I don't have iraudamp5. So iraudamp7s is the best class D I have ever used in the world
You can also download PCB design drawings on Infineon's website.
https://www.infineon.com/cms/en/product/evaluation-boards/iraudamp7s/
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You can consider using tda2005. It's easy to design.
I plan to spend 10 minutes designing it today. And upload circuit and PCB data.
This chip is about $0.50
IRS2092 spec sheet:
"International Rectifier’s proprietary noise isolation technology allows a high current gate drive stage and high-speed low noise error amplifier to reside on a single small silicon die"
Impressive...
It also comes in DIP16 (DIL16)...
"International Rectifier’s proprietary noise isolation technology allows a high current gate drive stage and high-speed low noise error amplifier to reside on a single small silicon die"
Impressive...
It also comes in DIP16 (DIL16)...
I have a couple of IRS2092 amps and have always thought they sounded great. My issue has been the dual rail PSU’s for smaller projects is a pain and makes the project like a discrete Class AB amp with a real chassis. At which point, I might as well use a Class AB amp.
It's just that many people don't understand the principle of amplifiers.
I can easily use 2sb817 2sd1047 to make a class AB amplifier that only uses + 40V.
And the output does not use capacitors. OCL circuit. Only 2 sets of amplifiers are required to use BTL mode output.
It's easy to make. And the performance is very good. It won't get hot.
Just because I personally don't like making power amplifiers from charger power supplies. So I didn't do it.
But it's really simple. If you are interested, I can draw a drawing for you.
Almost any transistor circuit. Can be made as a single power supply, such as + 50V -0 power supply. Just use BTL mode.
This has nothing to do with a certain model.
You can refer to the principle of tda2005 class ab.
Other circuits can also be used. For example, tta1943 is replaced by ttc5200. There is no difference.
https://www.diyaudio.com/community/...-scheme-class-ab-tda2005.388198/#post-7070413
Here I was going to discuss the performance differences of MOSFETs.
But now I find that more people pay more attention to single voltage amplifiers.
ok I'm going to explain the design of a single voltage amplifier. This can be applied to almost all power amplifiers.
For example, quad606 adopts 120v-0 DC power supply. It's simple. Almost all power amplifiers are OK.
https://www.diyaudio.com/community/threads/single-voltage-ocl-amplifier.388208/#post-7070463
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I have a question. Does BTL in solid state amplifiers cancel even harmonics in the same way as a P-P tube amplifier does? If not, why does that happen in an OPT circuit (tubes driving out of phase) but not in a bridge (two HS / LS pairs driving out of phase)?
I understand how to make bridged amps on single supply with no cap outputs. I have designed and built the SuSyLu - a 100w choke loaded SE Class A amp with balanced DC coupled output.
https://www.diyaudio.com/community/attachments/01ad7340-7c7a-4e0c-a763-d20e93961d64-jpeg.987583/
Very simple topology:
It sounds great - perhaps one of the best sounding amps I have heard.
I am just saying, for smaller simple amps, 100w with a SMPS single rail supply can make a great sounding amp. I have lots of great reviews on one of my commercial amps that uses this approach.
@jjasniew, even though my Susyamp is bridged, it still has a nice harmonic profile that is not odd order dominant like PP amps. Here is the FFT:
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Hum, FM Acoustics amps are more and more empty and more and more expensive.
I think the J Rowland has certaintly a better power supply than most can diy here (Pwm)
The little Infineon module is certainly cool but is there any advantage over a circlophon type or a class A ?
I have an old Chord amp... mosfet, 84V rails, pwm PS. Happy with it cause neutral...
I think the J Rowland has certaintly a better power supply than most can diy here (Pwm)
The little Infineon module is certainly cool but is there any advantage over a circlophon type or a class A ?
I have an old Chord amp... mosfet, 84V rails, pwm PS. Happy with it cause neutral...