Thanks for the help, I've been lurking here recently prior to buying my new headphones - beyerdynamic dt990's - these are the pro 250 ohm versions. They are nice, I cant wait for the head clamping feeling to die down with the "stretching exercises" I'm giving them (read as; stretching with books)
In the textboxes, I entered 250 ohm with 94.48 dB/mW. These are the specs of the Beyerdynamics DT770 Pro, rated at 250 ohms. If I wanted to listen at moderate listening levels, the voltage needed would be 0.94 vrms with 3.76 mA. The Fiio BTR5 out of its headphone jack supports 1.6-1.8 volts with 80mW.Been looking into getting myself a pair of Beyerdynamic DT 990 pro with and impedance of 250 Ohms. I have used digiZoid to figure out that i need 25,2 mW at 110 dB SPL. I'm not really looking to get an expensive Amp, but one that does the job. so I looked at the Behringer MICROAMP HA400, cheap and seems to be decent. Unlike their closed-back cousins, the DT 990 PRO are only available with the one relatively high impedance rating of 250ฮฉ. This means that theyโre at their best when connected to a high-level signal from the headphone output of a studio headphone amp or audio interface . 36. In the true spirit of Head-Fi I might suggest that the broken plastic part could be replaced by a set of DT1990 cans. Sources: Cambridge Audio 840c, Bluesound Vault II, Technics SL-1200/VM540ML, Ray Samuels F-117, DAC: Uber Bifrost Amplification: PrimaLuna EVO 300. Cans: Beyerdynamic DT-1990. atarione. Tvo4byH.