JLH Pure class A head amp

[kaushik]

Here JLH HiFi Headphone Amplifier PCB / Kit - Boards | Kits | Components | Modules | Tools
2 pcb and 3 full kits costed 57USD includes shipping


per kit just 20USD

This is a small yet high performance headphone amplifier board. The design is follow JLH-2005 class A amplifier. In this design, BD140 was replaced with BC560 and BD139 replaced with BC550. MJE3055 is used as driver transistor. A small heatsink is enough because 200mA Iq is enough for biasing headphone amplifier. The overall THD is only 0.008% (600Ohm, 1KHz, 0.5Vp-p). When listening with HD600, the high freq is clear, bass is full of engerge. Overall performance is excellent!

Features
- JLH-2005 pure class-A design
- Pure class-A design, highest performance
- 8V to 15V power
- Max 1W output
- Capable of driving 32? to 600? headphone amplifier
- 0.008% THD @1KHz, 600?, 1Vp-p
- DC bias, DC to 100KHz flat freq response
- Low Iq, small heatsink
- Heatsink included in kit

 

[iaudio]

Power Supply for JLH Headphone Amplifier - Boards | Kits | Components | Modules | Tools

Power supply for the same

 

[kaushik]

Power Supply for JLH Headphone Amplifier - Boards | Kits | Components | Modules | Tools

Power supply for the same

Thanks iaudio , but for cost conscious that power supply is not needed to be imported as the shipping and customs of heavy items may make the build expensive

locally well made EI transformer(max 300Rs) and capacitor bank can be procured ,
even pair of panasonic 10000uf (200Rs at max)will do , that i can get from the industrial suppliers .
other components bridge - 20Rs,0.1uf/200V-10Rs
board connectors -70Rs

full power supply unit will go <700Rs

 

[Audiodoc]

Yes kaushik is right with respect to cost. A locally made toroid from torotrans will also cost around 500 bucks. Have you purchased the same.

A pair of good high value capacitors parallel with a pair of low value (1000mfd) low esr capacitors will do fine.

 

[captrajesh]

Are you guys not overlooking the cost of a 'Bridge Rectifier' and the associated circuitry?

 

[kaushik]

Are you guys not overlooking the cost of a 'Bridge Rectifier' and the associated circuitry?

The tiny tiny bridge will do duty for 20Rs , am i going wrong ?

 

[iaudio]

Kaushik, did you build it/order it?

 

[kaushik]

Pure class A HP amp lovers have to do a GB or start ordering with 57USD.

My HP needs re cabling/re padding.. hate to touch that activity

so AMP building in in pipeline.

 

[doors666]

10,000 mfd 50v rubycon is available at amar radio for 175/-. hp amp will require much lesser voltage, hence less cost. but seriously, why so much capacitance is needed for a hp amp, whatever being the class.

diodes are 10-20 bucks a pop.

O2 kit with good quality parts with shipping comes close to 40$. only needs a transformer 15vac 500ma, connectors etc are also included. It has onboard power supply and charger for rechargeable batteries (2x9v). Considering everything, there isnt much savings with jlh. Quality wise, i think both should be very good hp amps.