100W Ultimate Fidelity Amplifier

Hy Mr. Mile i have a problem with my ax14, for one module the dc offset is big
21mA and for the another is ok only 7mA. What is the cause? Can help my? I want to use this for car audio. Thanks

You mean.... mV!
These values are OK, and could not make the system sound so badly.
Check the components for quality, and compare voltages between both channels at different places around the circuit. Also check your sound source (invert input channels and/or output speakers to compare).
 
A question for Mr. Mile,
can a single PCB of attached PSU be used for FX-8/ FX-8 Bimo mod stero channels?
Would it work well? or for that matter any of your SS Class-AB /Chip amps.

I wanted to make a PCB design for simple low cost bulk PSU with external 35A chassis mount dual/single bridge rectifiers. The idea is to adapt it to any class AB amplifier so that a beginner can easily assemble one at low cost with cheap chinese PCBs.

regards
Prasi
 

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What kind of power supply do you use for this amp in the car?

I`ts a power supply from aliexpress, not home made. If mister Mile have a schematic or someone of power supply for car is very good, but..... for the moment I have no pcb or schematics for car power supply. If someone have please post here.

PCB size: 140mmX128mm
- Output: ±50V
- Power supply: DC9-16V
- Output voltage: ±44V(12V input), ±50V(14V input on car)
- Auxiliary power supply output: ±16V(12V input), ±18V(14V input)
- Rated power: 500W
- Turn on/off frequency: 100KHz
- Efficiency: >95%
 

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Founder of XSA-Labs
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Founder of XSA-Labs
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Nicely done , congrats and very sharp silk transfer on pcb. Wondering if the pcb is manufactured or home etched?
Final heat sinks will be bigger? Bias level?

Regards
Prasi

The silk on that board is "too sharp" to be homemade, but we may be surpirsed at the level of quality possible at home nowadays.

The FX8 Bimo mod wit Prasi layout is indeed a nice sounding amp and is currently my main amp playing in Class A with a 1.5amp bias! :D

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The silk on that board is "too sharp" to be homemade, but we may be surpirsed at the level of quality possible at home nowadays.

The FX8 Bimo mod wit Prasi layout is indeed a nice sounding amp and is currently my main amp playing in Class A with a 1.5amp bias! :D

attachment.php

Very beautiful case.. From diyaudiostore here?

Nice room heater:D.
 
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Yes, it's the Dissipante 3U (good for 60w dissipation per channel) with UMS heatsink bolt holes. Luckily the FX8 fits standard holes. I had to cut all the openings for jacks/plugs on back panel myself. I wish the store would offer a standard back panel like all the ones on Aliexpress who have: two RCA's, two pairs of banana binding post, 1 IEC(with jack/fuse/power switch)That would make life a lot easier for us. But a nicely made case, otherwise.

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Really, are these 7 holes too much to ask for as standard offering?
 

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This is superb, Prasi. I love how you aim to maximize what we can do in 16 square inches of 100 square cm's! It saves $ and amp case real estate.

For those who have not used cap banks before: they are one of the secrets of a powerful and dynamic sounding amp. The 16mm dia caps can be rather cost effective Aliexpress bag of 50 x 2200uF caps and really lower the ESR for great bass impact.
 
This is superb, Prasi. I love how you aim to maximize what we can do in 16 square inches of 100 square cm's! It saves $ and amp case real estate.

For those who have not used cap banks before: they are one of the secrets of a powerful and dynamic sounding amp. The 16mm dia caps can be rather cost effective Aliexpress bag of 50 x 2200uF caps and really lower the ESR for great bass impact.

thanks x, yes, thats the idea here to lower ESR. I will post gerbers once I am done with fine tuning.