Studio Series Headphone Amplifier construction thread

Bespoke Constructor
Joined 2006
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Hello forum members hope all is well
I know there are numerous headphone amplifier designs (very nice ones in the DIY audio store) plus I am a big fan of the JLH single ended Class A design but I have become very fond of this design and the PCB layout (no surface mount and big solder pads for us oldies)
Also to my ears sounds very nice, I have decided to make a test bed for tweaks and document on this wonderful forum

I decided to make my 1st module with good quality budget components with a few notes below

1. The op amp is a OPA2134 ( I have used an OPA2134 audio op amp here for best budget performance) but will try other op amps once completed
2. Matched all the transistors 1st time I have done this
3. Used Jantzen output inductors ( from HiFi collective UK based online company ) 0.005mH Jantzen Air Core Wire Coil AWG20, 0.8mm diameter wire
4. Cardas`s quad eutectic solder in the build

I think this is a very good sounding headphone amplifier sure there are better designs but thought its worth a mention and would be fun to see once built how it compares with other designs

Spec Below
 

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Bespoke Constructor
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Ok have completed the PCB, Just need to add the op amp / Earth Tag and PSU fuse
few pictures ..
will upload the test bench later as still work in progress
 

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Bespoke Constructor
Joined 2006
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So this is a pic of my test bench (still not 100% finished) this comprises of the following?

1- mains inlet with power switch plus power indicator & fuse
2- 2 power transformers (one dedicated to the headphone amplifier and the other for remote control and muting relays) make Talema
3- remote control PCB
4- ground loop break PCB
5- Two independent muting relay boards
6- Aux control PSU (12v Audiowind SR-1 / A230 ver 1.2 PCB)
7- updated PSU with better components - P8042-1 PSU
8- 50k log volume pot

IMG_0470.JPG
 
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Bespoke Constructor
Joined 2006
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I currently have 4 head phone amplifiers to compare against each other

1 - This one in this thread (Studio series headphone amplifier)
2 - JLH Class A single ended Headphone amplifier (currently my favourite)
3 - The Whammy (DIY Audio store)
4 - High-Performance Stereo Headphone Amplifier (SC magazine sept 2011 vol24 number 9)
 
Bespoke Constructor
Joined 2006
Paid Member
hello Mandu

this design was published in the Australian electronics magazine (Silicon Chip)
Nov 2005 - for some reason years ago I purchased loads of PCB's at a good price and have always been pleased with the sound quality also the op amp can be replaced like the 627 as an example
regards