Vista_Nueva :
I have them loud enough so that I can hear them clearly when they next to me on my desk.
It meant for wearing and not desktop. There are speakers for that application.
However in scale of 1 - 10 what is your volume levels are? What kind of sound procesor do you have? Computer Onbaord, Expansion Card or External Ampifier?
Distortion is number one enemy of sound radiation. You should understand the frequency response of each equipment and the source of the audio you are using.
HD280Pro Item No. 004974 - Headphones Specs:
Transducer Principle Dynamic
Frequency Response 8 Hz - 25 kHz
Nominal Impedance 64 Ohms
Weight Wo Cable 285 grams
Characteristic Spl 102 dB, (at 1 kHz/1Vrms)
Ear Coupling Circumaural, Closed
Distortion <0.1%
You will need an Headphone Aplifier to get the best of this headphone. But that could get expensive. expansion card is good enough for this headphone.
Sennheiser HD 280 is a very good headphone so when you here it Belch or crackle that means that is distorted. It could be that your volume level is too high for the amp. so check your tone settings your bass & trebel maybe too high. Amplifying is different than tuning, by changing the characteristic of the sound you are now distorting the original sound. Therefore that distortion is multiply by the amount of amplification applied.