I,m new here! ( fake at4040 from Aliexpress )

[Euro-Azteca]

Hello! I'm new here and this is my first post.
This week I received a counterfeit AT4040 microphone from Aliexpress. I bought it knowing it's a counterfeit. I'm not someone who understands circuits, soldering, capacitors, etc, the most I can do with microphones is change the capsule of a microphone.The physical appearance of the AT4040 from Aliexpress is practically identical to the original model. Out of curiosity, I decided to open the microphone to inspect it and noticed that the circuit looks very similar to the original. The capsule also looks very similar, although I doubt it is the same as the original. I've never used the original model, so I wouldn't know if its sound is similar. The other microphones I have are the NT1 (4th gen), Stellar X3, King Bee II, and the Se X1S. I mention this in case the AT4040 sounds similar to any of those. What do you think about the circuit of this fake microphone? I only paid 139 euros (a little over 140 dollars) with shipping included. If I modify it, the most I can do is change the capsule, and it would be for a cheap CK12 from Aliexpress (something between 20 and 40 dollars). And in case this circuit gives results similar to the original, do you think a CK12 capsule from Aliexpress would give it good sound? Cheers ( and excuse my weird english, I'ts not my primary language ).

View attachment IMG20250129193330.jpg

 

[micolas]

@Euro-Azteca
Welcome to GDIY!
Everything is possible here!

 

[micolas]

So,
The capsule in the picture may be a small / medium electret.
AliExpress style CK12 is probably a K67 style LDC with edge termination. It needs polarization voltage (and
probably a deemphasis circuit).

 

[micolas]

@Euro-Azteca
For a good organization of topics, you must open a new thread titled, for example:

AliExp Fake Audio-Technica AT4040 - mods/builds

You will repeat post #1 from this thread:

https://groupdiy.com/threads/i-m-new-here-fake-at4040-from-aliexpress.89872/post-1187545

Those who have the experience and desire to help you, they will, there are extraordinary people here.

¡Eres bienvenido a nuestro grupo!

 

[jp8]

So,
The capsule in the picture may be a small / medium electret.
AliExpress style CK12 is probably a K67 style LDC with edge termination. It needs polarization voltage (and
probably a deemphasis circuit).

Indeed, looks like a 25mm electret, not needing external polarization voltage. But I'd swear I see a Hartley oscillator circuit next to the light-blue trim pot. Two coils (the two dark blue parts), BJT and to the right the voltage multiplier diodes and capacitors. Typically the ingredients for a polarization voltage generator Funny...

Jan

 

[micolas]

Indeed, looks like a 25mm electret, not needing external polarization voltage. But I'd swear I see a Hartley oscillator circuit next to the light-blue trim pot. Two coils (the two dark blue parts), BJT and to the right the voltage multiplier diodes and capacitors. Typically the ingredients for a polarization voltage generator Funny...

Jan

Hi Jan,
Sometimes I applied additional polarization voltage to electret capsules to increase sensitivity
Or:
121 would mean 120uH
102 would mean 1000uH
Such large inductors are not often used in dc/dc
They are probably 120pF, 1nF capacitors

 

[jp8]

Sure, that's feasible. But would it be needed with these 25mm capsules? Sensitivity of such capsules is adequate without extra polarization voltage. At least, all those 25mm prepolarized capsules I have are.

The real AT4040 has an externally polarized capsule. My assumption is the manufacturer just blindfoldedly copied the AT4040, without actually understanding what they were copying. And then try to save costs by using cheaper components, instead of re-engineering the circuit. Typical for Chinese copy-cats.

Jan

 

[micolas]

My assumption is the manufacturer just blindfoldedly copied the AT4040, without actually understanding what they were copying.

Jan

...How some copied double DC/DC, after U87ai/U89 with differential polarization voltages (+ and -) for microphone only Cardioid
(Perception 220)
http://recordinghacks.com/microphones/AKG-Acoustics/Perception-220

 

[jp8]

Haha, that's a perfect example of what I meant!

Such redundancy is only justifiable if the manufacturer can reduce logistics and inventory costs by carrying only one PCBA. But I assume that is not the case in your example.

Jan

 

[Euro-Azteca]

Thank you very much for your comments. I have already found a buyer for this fake microphone (I advertised it as a "Chinese condenser microphone") and offered it for 80 euros. I will see if I can get the money to buy an original AT4040 at a store in my city next Friday (it costs 398 euros). I will connect it to an Audient iD14. Cheers, community!

 

[micolas]

Thank you very much for your comments. I have already found a buyer for this fake microphone (I advertised it as a "Chinese condenser microphone") and offered it for 80 euros. I will see if I can get the money to buy an original AT4040 at a store in my city next Friday (it costs 398 euros). I will connect it to an Audient iD14. Cheers, community!

It's ok. Sounds like a good plan.
Success in music production!
¡Te deseo mucho éxito!
¡ Cheers !