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1DIFFQC Class AB 220Watt 4Ohm Amplifier Module

modulardesign

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Amplifiers each have their own signature and distortion characteristics. We don't want them to add unpleasant things that weren't there, but were ok for any pleasant additions so long as they are moderate. Class A/B provides the warmest fullest bass. Class A has the cleanest bass but can be lean. Class D can be a mixed bag on the quality of the bass it can be too dry in some class D amplifiers but not all as technology has greatly changed over the years. With so many options people usually pick what works for them. Some people are rather perceptive and can pick out an amplifier based on its sound signature and even distinguish mosfet outputs from BJT outputs. But at the end of the day its sound signature should be in the set of acceptable signatures and then one can just enjoy the music rather than be too analytical.
 
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modulardesign

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Doodski

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Are you quoting the 220W total or per channel? Just wondering because of the 40V rails. If they load down to ~29.66V then the amp puts out 110W/ch.
 
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modulardesign

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Dimensions
The PCB is very compact providing a very high power density in just 114.53mm * 114.55mm . Allowing for creation of a multichannel amplifier and or active speaker system.

Power Source​

Unregulated +/-42VDC

Mounting​

You will need a suitable heatsink with at least 0.6 C/W dissipation and mounting kit. The module has holes for mounting. M3 screws and standoffs would be suitable for attachment.

Details​

The amplifier should reach full power at line level voltages. You may use a preamplifier of your choice.
R24 is a 25 turn pot, center it at 12 turns, then start your adjustments from there. Measure the voltage across R11 with a multimeter and adjust R24 until the voltage across R11 reads between 10mV to 20mV. Bias the output devices at 100mA (20mV) for better performance THD will be around 0.05%
Have fun and let us know what you think

Mono $127USD,Stereo $254
 
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modulardesign

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Are you quoting the 220W total or per channel? Just wondering because of the 40V rails. If they load down to ~29.66V then the amp puts out 110W/ch.
Yes. For linear supply use a suitably sized transformer and high ripple current capacitors so that the rails dont sag more than 5volts
 

Chrispy

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Amplifiers each have their own signature and distortion characteristics. We don't want them to add unpleasant things that weren't there, but were ok for any pleasant additions so long as they are moderate. Class A/B provides the warmest fullest bass. Class A has the cleanest bass but can be lean. Class D can be a mixed bag on the quality of the bass it can be too dry in some class D amplifiers but not all as technology has greatly changed over the years. With so many options people usually pick what works for them. Some people are rather perceptive and can pick out an amplifier based on its sound signature and even distinguish mosfet outputs from BJT outputs. But at the end of the day its sound signature should be in the set of acceptable signatures and then one can just enjoy the music rather than be too analytical.
Do you have some measurements to back that up?
 
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modulardesign

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Returns accepted within 30 days.
If your new to the field you can use below procedure to set bias
  1. Place the circuit board on a non-conductive surface.
  2. R24 is a 25 turn pot, center it at 12 turns, then start your adjustments from there.
  3. Set the two DC workbench power supplies to 20VDC and 300mA respectively. Connect one of the black terminals to the other red terminal to produce zero volts, so now you have a (+20,0,-20)VDC dual supply. Or use a bench power supply with dual voltage and adjust the output voltage to +/-20VDC, 300mA.
  4. Connect bench power 0 to PCB PWR GND,-20 to PCB -40VDC,+20 to PCB +40VDC, and turn on the output.
  5. Measure the voltage across R11 with a multimeter and adjust R24 until the voltage across R11 reads between 10mV to 20mV. Bias the output devices at 100mA (20mV) for better performance THD will be around 0.05%
  6. Use a multimeter to measure the voltage between the PWR GND and SPEAKER terminals. This should preferably be less than 50mV.
  7. Use a function generator to apply 20Hz, 1kHz and 20kHz sine waves of 0.2V to the signal and GND terminals of the PCB.
  8. Using an oscilloscope between speaker GND and SPEAKER, observe the resulting signal. There should be no ringing or oscillation. This is an exceptionally stable amplifier
 

antcollinet

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Amplifiers each have their own signature and distortion characteristics. We don't want them to add unpleasant things that weren't there, but were ok for any pleasant additions so long as they are moderate. Class A/B provides the warmest fullest bass. Class A has the cleanest bass but can be lean. Class D can be a mixed bag on the quality of the bass it can be too dry in some class D amplifiers but not all as technology has greatly changed over the years. With so many options people usually pick what works for them. Some people are rather perceptive and can pick out an amplifier based on its sound signature and even distinguish mosfet outputs from BJT outputs. But at the end of the day its sound signature should be in the set of acceptable signatures and then one can just enjoy the music rather than be too analytical.

Quite a lot of audiophile folklore in that post.
 
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modulardesign

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Do you have some measurements to back that up?
Diversity in humanity results in diverse tastes and affiliations. Diversity allows humanity not to be caught up in local optimization.
 

antcollinet

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Dimensions
The PCB is very compact providing a very high power density in just 114.53mm * 114.55mm . Allowing for creation of a multichannel amplifier and or active speaker system.

Power Source​

Unregulated +/-42VDC

Mounting​

You will need a suitable heatsink with at least 0.6 C/W dissipation and mounting kit. The module has holes for mounting. M3 screws and standoffs would be suitable for attachment.

Details​

The amplifier should reach full power at line level voltages. You may use a preamplifier of your choice.
R24 is a 25 turn pot, center it at 12 turns, then start your adjustments from there. Measure the voltage across R11 with a multimeter and adjust R24 until the voltage across R11 reads between 10mV to 20mV. Bias the output devices at 100mA (20mV) for better performance THD will be around 0.05%
Have fun and let us know what you think

Mono $127USD,Stereo $254
Are you aware there are some rules to follow here if you are a manufacturer/dealer?

 

Chrispy

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Yes sir, folklore is the backbone of our existence

this does not mean qualitative research is useless. If we sample 400audiophiles what would the results be?
Probably a lot of nonsense. Especially the audiophool side of the fence which you seem to gravitate towards? Folklore is the backbone of whose existence? :)
 
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modulardesign

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Are you aware there are some rules to follow here if you are a manufacturer/dealer?

https://www.audiosciencereview.com/...er-with-commercial-endorsement.18155/[/QUOTE]
I read the introduction and sampled a few posts, did I break something?
 
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modulardesign

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Here's a guide to grounding audio equipment. There are many schemes to grounding equipment. Each Module can be grounded to chassis through the mounting holes. Or Grounding to chassis can be provided via the power supply module. Note that chassis ground connects directly to power supply earth. There may be up to four ground planes in an amplifier. small signal ground, digital ground, high power ground, chassis ground
 

Doodski

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You did not break anything that I am aware of but @modulardesign here at ASR we generally don't think subjectively about amp classes or other audio related stuff. Most everybody here is mostly objective about most stuff. There are subjectivists but they oftentimes don't fit in well. That's what @Chrispy and @tonycollinet are suggesting.
 
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