Translinear Current Mode amplifier (?)

[latoresp]

Shearching on aliexpress i found this amp

it claims to:

"buffer stage uses cross-conductor current mode patented technology, high current class A output. output stage and load uncolupled capacitor"

ok i know nothing about electronics. this have any sense?

all we know chiness and her marketing...

as i know, specs seems not too bad. anyone knows something about this?

priced arround 310€ with shipping.

Recommended load impedance: 4-16Ω
Output Power: 70Wx2 RL=4Ω.THD+N=0.8% || 40Wx2 RL=8Ω,THD+N=0.6% || 25Wx2 RL-16Ω,THD+N=0.4%
Output voltage swing: 40Vpp
Distortion(@1kHz): 0.07(RL=4Ω, G=0dB, IN-0.6rms) || 0.006(RL=8Ω, G=7dB, IN=0.6rms) || 0.002(RL=16Ω, G=14dB, IN-0.6rms)
Frequency response:5-220KHz
Input sensitivity: 15.0Vrms(PO=Hi, G=0dB) || 4.3Vrms(PO=Hi, G=7dB) || 2.0Vrms(PO=Hi, G=14dB)
Noise: 2.0uV(G=0dB, RL=4Ω) || 3.4uV(G=7dB, RL=8Ω) || 9.6uV(G=14dB, RL=16Ω)
Gain: 40dB
SNR: 130dB(PO=Hi, G=0dB) || 121dB(PO=Hi, G=7dB) || 106dB(PO=Hi, G=14dB)

 

[jacques antoine]

Cannot be class A: look at the small heathsink and tiny 100W transformer.
Not class D either due to absence of inductors.
Class AB at best with transfo-limited output power, maybe 20Wx2 at 8ohm.

 

[BesPav]

high current class A output

Too small heatsink to be true.

 

[levinson mark]

Current mode gain amplifier

 

[OldDIY]

There is not enough sense in the words, the figures given are contradictory.
Link to the manufacturer's Chinese website.
Amplifier or class D or B (not clear).
There are no reviews. Single sales.
https://aliexpress.ru/item/1005001881287222.html?spm=a2g2w.productlist.0.0.52eb65baRWEnni

 

[SonocusEric]

It could be using the whole chassis as a heatsink.

Regardless i got a hunch that its a bakoon ripoff

 

[OldDIY]

100w transformer, 80-90w power available.

 

[stinius]

The output Voltage swing is stated to be 40Vpp.
So at the best that will be 25W at 8 ohm load.

I see that member Levinson Mark from China has copied a whole bunch of designs that he calls " Current mode gain amplifier "
Who knows, maybe he is the owner of the claimed "patent" 🙄

Stein

 

[levinson mark]

Pioneer current mode gain circuit

Current mode gain circuit is not a mysterious technology. Pioneer used current mode gain circuit in 1980

 

[levinson mark]

Satri and Marantz current mode gain circuit

 

[Antoinel]

Hello levinson mark.

The insides of your amp are professional, well-put together and neat.

Are its circuits an invention; improving on those you showed above?

Thanks for showing schematics; they are always food for thought and analyses.

Best wishes
Anton

 

[padamiecki]

me too,
thank you for sharing!
very inspirative!

 

[as_audio]

Hello levinson mark.

The insides of your amp are professional, well-put together and neat.
...

I do not see LM sharing an amp build picture.

 

[MarcelvdG]

latoresp, where did you see the term translinear?

Translinear is a term invented by Barrie Gilbert for circuits using loops of semiconductor junctions (usually base-emitter junctions of bipolar transistors) to realize nonlinear functions. The uses I know of in amplifiers are:

In class-AB amplifiers, to define how the output current should be split between the push and the pull side of a push-pull output stage

In current mirrors

To split the feedback current between the N and P side of a "CFB" input stage

 

[Antoinel]

I do not see LM sharing an amp build picture.

My mistake. I assumed the pictures in the first 2 posts showed it.