[Andymaxwell]

 

@TheAlpha  Haha, wicked, love the coincidence!   I've only just received the JRC4556 from Australia and haven't got round to buying the others yet. Really looking forward to listening to it and will let you know my thoughts when I have.
 
Really appreciate your thoughts on them buddy -so we've just got to get the right one for our own headphones. And the upside is when you change your headphone, you change your amp signiture. Excellent!
 

 

 

[nofacemonster]

Which OP chip has the dark mellow laid back sound with heavy bass....? I love the sound signature of KZ ZS1. I am looking for something similar, something that sounds warm and tube like.

 

[bootdsc]

Which OP chip has the dark mellow laid back sound with heavy bass....? I love the sound signature of KZ ZS1. I am looking for something similar, something that sounds warm and tube like.

When you build the cmoy if you increase the capacity of the input and or output capacitors you will change the roll-off and it will give you a warmer sound. If I was home I could tell you exactly the size I use but it's been a while since I built my last one. I have well over a dozen similar amps I have built. Did you buy a kit or scratch built?

 

[nofacemonster]

When you build the cmoy if you increase the capacity of the input and or output capacitors you will change the roll-off and it will give you a warmer sound. If I was home I could tell you exactly the size I use but it's been a while since I built my last one. I have well over a dozen similar amps I have built. Did you buy a kit or scratch built?

Thank you for replying me. I am sorry for barging in and sounding like a pro but i am not. I just asked because i ordered a cheap XU-09 headphone amp from eBay and it is said the OP amp can be changed to any desired chip. So since i like warmer mellow sound and i thought i'd change the stock chip with a more mellower warmer sound.

 

[madnanny2]

Filburt is right. Some day all DIYers realize that TRUE amplification started on the day they dropped in AD8397 and all before was cheating themselves they had build an amplifier. Cmoy may act as an amplifier when compared to low power mp3players having a couple of miliwatts output, and that's all. And yes, chips working close to their current limits distort significantly. This is the case with all plain audio and non-audio op-amps. Regarding OPA2227 it is not that slow. OPA2277 is intended for precise DC devices but this chip is totally unsuitable for audio IMHO.
What I suggest is copy all voltage feedback from low-noise PINT version and use AD8397. As a virtual ground - op-amp + BUF634 or Sijosae AB Virtual Ground with electrolytic caps on output side, no cap divider before transistors! It is wrong and screws up idea of the circuit. Trust an electronic engineer.

i am using opa2227,it came in my jds labs bb,i like a smooth treble,is there an op amp i could replace this which wasnt bright