This headphone amplifier has a typical FET spectrum.
That is most 2nd harmonics.
The distortion is rather low for being only 3 transistor amplifier.
That is most 2nd harmonics.
The distortion is rather low for being only 3 transistor amplifier.
Here at Mouser can all 3 transistors be bought:
https://eu.mouser.com/ProductDetail...70A-TO-92-3L-BK?qs=T%2BzbugeAwjh6PhuTSbSung==
https://eu.mouser.com/ProductDetail/Diodes-Incorporated/ZVP3310A?qs=CT2LuZh/7EOPeKK9PLkBIg==
https://eu.mouser.com/ProductDetail/Vishay-Siliconix/IRF610PBF-BE3?qs=7MVldsJ5UayB2tWAzu7GXg==
They are in stock.
https://eu.mouser.com/ProductDetail...70A-TO-92-3L-BK?qs=T%2BzbugeAwjh6PhuTSbSung==
https://eu.mouser.com/ProductDetail/Diodes-Incorporated/ZVP3310A?qs=CT2LuZh/7EOPeKK9PLkBIg==
https://eu.mouser.com/ProductDetail/Vishay-Siliconix/IRF610PBF-BE3?qs=7MVldsJ5UayB2tWAzu7GXg==
They are in stock.
Here is the Fourier showing spectrum.
As can be seen 2nd harmonic is very dominant.
As can be seen 2nd harmonic is very dominant.
I decided to study this amplifier. I used Qspice for the simulation. I applied more correct models for the first transistor and for the third. I also reset the connection and reduced the correction capacity. Unfortunately, the amplitude of the input (or output) signal is not specified.
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I have tested with 900mV output across 32 Ohm.
That equals +10 dB to the SPL.
@bordodynov
What are your conclusions after SPICE testing?
That equals +10 dB to the SPL.
@bordodynov
What are your conclusions after SPICE testing?
Lineup does not build, he designs 🙂
Its up to us to build it. I wish I had my stuff back from storage, i would breadboard it in an hour.
Small heatsink is required for 200mA current.
Its up to us to build it. I wish I had my stuff back from storage, i would breadboard it in an hour.
Small heatsink is required for 200mA current.
that looks really nice i recently build my own amplifier but it actually was too loud. i also saw that an simple current buffer can be enough for a lot of headphones,
I concluded that modeling in different programs with different models gives quantitatively different results. The distortion of the circuit for three transistors is quite acceptable with sufficient acoustic output power. I've upgraded your scheme a bit. It is not correct to look at distortion at 1 kHz. You need at least 10 kHz.
