I would just like to say that I have read a lot of your posts from everyone and I'm amazed and envy everyone's knowledge to make circuits. I think, but I might be wrong. Amps are the easiest of all components to make. ( compared to like tuners and CD players, etc. )But to still have the no-how to make amps is beyond me. How did you guys get that knowledge? I would really like to know. I have been a fan of high end equipment for years and I would like to know what components do what in a circuit. I just don't no where to start .
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Hello. Since i don't want to litter diyaudio with new threads, i will ask in this one.
It is not truly about designing class d amplifier, but very close. I couldn't find any info on this:
So i have a few questions:
1. Can soft dome tweeters be driven of filterless? I dont know what "soft dome" means, thats only info about them. Maybe i need to add output filter (which kinda makes this into class D designing 😀)
2. I only have one free pam8403 channel for them, and they make 2 ohm load, while pam8403 designed for 4ohm, could it work with high pass at aprox 6000hz because power is very low that high?
I could add 1.2 ohm resistor to reach 3.2ohm load, it would be still louder than series speakers. Only if its needed of course.
Thanks in advance, and sorry for invading thread 😀
It is not truly about designing class d amplifier, but very close. I couldn't find any info on this:
So i have a few questions:
1. Can soft dome tweeters be driven of filterless? I dont know what "soft dome" means, thats only info about them. Maybe i need to add output filter (which kinda makes this into class D designing 😀)
2. I only have one free pam8403 channel for them, and they make 2 ohm load, while pam8403 designed for 4ohm, could it work with high pass at aprox 6000hz because power is very low that high?
I could add 1.2 ohm resistor to reach 3.2ohm load, it would be still louder than series speakers. Only if its needed of course.
Thanks in advance, and sorry for invading thread 😀
Oh i just realised that i shouldn't have posted in this thread. Sorry. I will start my own thread.
-> Can soft dome tweeters be driven of filterless?
Generally not because lack of inductance. But you may simple add some 22uH in series with them. (Otherwise they might burn out due to HF-current)
Generally not because lack of inductance. But you may simple add some 22uH in series with them. (Otherwise they might burn out due to HF-current)
Thanks. Since pam8403 is BTL, do i need two inductors? One on pos output, and one on neg?
3W of power 😱 , no filters required . If you are so affraid , make a common mode inductor . 3-5 turns on a 12-16mm dia ferrite ring .
Depends on the tweeter. If it's rated 4+W , there won't be any harm. Neither less you will only need one inductor. Higher inductance gives lower cutoff at the upper end.
Diminish, 3-5 turns on 12-16mm gives what?
Kinda useless information.
Diminish, 3-5 turns on 12-16mm gives what?
Kinda useless information.
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Thanks. Does 22uH give cut-off of about 29khz with 4 ohm load?
So in my 2ohm load case i shouldn't use 10uH ?
Can you measure the inductance of your tweeter ?
It'll be more easy to calculate the value of the inductor you need.
If i could measure inductance, i probably would have everything figured out. I dont have tools forr that.
Yes, thats actually all. 22uH is a good rule of thumb, which works most. (Its just for compensate the HF-current)
You'll defo hear when it is to much of comepensation.
You'll defo hear when it is to much of comepensation.
Hello, I ordered this amp but i hear that when you turn it on it works on 70% volume and with SMD Buttons you can volume up or lower.. so i want make when you turn on amp its automatic on max volume.. how its possible to make?
Screenshot by Lightshot
Screenshot by Lightshot
You'll need to change the corresponding PSKeys in the CSR BT chip. Not possible without a programmer for there modules and the Toolkit provided by CSR.
Have you checked if increasing the gain via the 2 dip-switches is already enough "ompf" for your needs?
Have you checked if increasing the gain via the 2 dip-switches is already enough "ompf" for your needs?
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Mini amp repair.. wrong parts?
Hey guys, still pretty new to all this.
So, I accidentally pulled the shaft out of one of my pots while trying to remove the knobs. I replaced a B100k with a B100k on the balance knob. Now it acts as another volume knob. All of them read B100k, so I don't understand why it's not doing the same thing it did before.. any ideas?
This picture is of a new one that I ordered with it's original pots. The one with the green sticker is the balance. What is different about this pot so I can repair the other one with the right part?
Thanks for any insight!
sorry it's sideways 😀
Hey guys, still pretty new to all this.
So, I accidentally pulled the shaft out of one of my pots while trying to remove the knobs. I replaced a B100k with a B100k on the balance knob. Now it acts as another volume knob. All of them read B100k, so I don't understand why it's not doing the same thing it did before.. any ideas?
This picture is of a new one that I ordered with it's original pots. The one with the green sticker is the balance. What is different about this pot so I can repair the other one with the right part?
Thanks for any insight!
sorry it's sideways 😀
An externally hosted image should be here but it was not working when we last tested it.
Sorry, I forgot to mention. The amp is the Kinter MA-180 and there are four knobs and a power switch.. volume, bass, treble, and balance. 
I've always wondered why my Behringer NU3000DSP class D amp sounds so flat in the treble, so I decided to measure it acoustically (noise) connected to my ribbon speakers.
I normally use it as a bass amp, where it's doing a great job.
As you can see, on the red line, there's a whole lot of noise in the treble and very poor phase behaviour. Its the same on both channels, and the amp is setup in
straight mode without the DSP in operation.
For comparison, the blue graph is from a Nad M3.
Can the problem be due to a much to low modulator frequency?
I normally use it as a bass amp, where it's doing a great job.
As you can see, on the red line, there's a whole lot of noise in the treble and very poor phase behaviour. Its the same on both channels, and the amp is setup in
straight mode without the DSP in operation.
For comparison, the blue graph is from a Nad M3.
Can the problem be due to a much to low modulator frequency?
