May I use BC109 and BC179 instead BC550C and BC560C?   Thanks.

I had measured DC offset on Matrix M Stage headphone output and found:   Left channel - 0.8 mV Right channel - 8.4 mV   I tuned blue trimpots after LM 337 and LM 317 to 15V each and I changed opamp (OPA 627 instead OPA 2134) and result is the same (same DC offset).   I noticed one...

I would like to buy headphones for listening to classical and ambiental music... I had AKG recently (AKG 701), but I didn't liked them at all. (Because of sterility and power demands.)   My amplifier is going to be AMB CKIII. (Right now, it is in process of making.)       Any...

I had Matrix M-Stage and AKG K701 phones. I wasn't satisfied with Matrix, because stock model didn't have sound stage at all, and was dull and sterile. After few mods (changing opamp and capacitors) there was improvement in deepness, but low frequency didn't have precision and had too much...

Right now I have AKG 701, but I want to buy another headphones under 250 USD.   Beyerdynamic, AKG (again), Audio Technica? I don't know... How good are AKG K240 or Audio Technica AD700. What is the difference? What about Beyerdynamic DT800? Maybe, there are other options?   I need...