IEC61938 on driving headphones
Jul 18, 2007 13:25:08 GMT
Post by PinkFloyd on Jul 18, 2007 13:25:08 GMT
Whoah! Been on the phone to Beyer for 30 minutes, phoned up to ask them "what impedance?" and the guy went into some seriously mind boggling stuff which went totally over my head! He was talking so fast and so passionately I just couldn't digest it!
Basically Beyer say the optimal output impedance of an amp using their DT-880 is 250 ohm. This will give you the flattest response, plugging them into the 16 ohm output of an ipod will not do them any favours but will result in a more unnatural (yet pleasing sound) He described it as the classic smiley face response with bass up mids down and treble up.
He went on to say that some of the competitors design their headphones to sound like this... for flattest response with DT880, however, 250ohm is the desired output impedance.
He explained that impedance is not everything we are also taking the materials, the loading, the enclosure into equation... closed, open, semi open. Impedance should only be considered a rough starting point and as the 'phones are to be used in domestic situations trade offs must be expected but for optimum performance, if you use Beyer DT-880 / DT-770, DT-990 then your amp output impedance should be 200 - 250 ohm.
I really wish the guy had been talking slower as he was giving out some VERY interesting stuff! I didn't have a pen handy so couldn't take notes. He did say that no way is 0 ohm suitable for beyer 'phones.... 120ohm is marginal but 200 - 250 ohm optimal for the most honest reproduction.
A most informative man and I'm only sorry I can't replicate everything he said here, he went into every detail (formulae, materials, impedance, mass, headphone enclosure types.... yikes! the lot, and at great speed)
Well worth phoning Beyer UK technical but have a pen and paper handy and expect to be on the phone for ages!!
Basically Beyer say the optimal output impedance of an amp using their DT-880 is 250 ohm. This will give you the flattest response, plugging them into the 16 ohm output of an ipod will not do them any favours but will result in a more unnatural (yet pleasing sound) He described it as the classic smiley face response with bass up mids down and treble up.
He went on to say that some of the competitors design their headphones to sound like this... for flattest response with DT880, however, 250ohm is the desired output impedance.
He explained that impedance is not everything we are also taking the materials, the loading, the enclosure into equation... closed, open, semi open. Impedance should only be considered a rough starting point and as the 'phones are to be used in domestic situations trade offs must be expected but for optimum performance, if you use Beyer DT-880 / DT-770, DT-990 then your amp output impedance should be 200 - 250 ohm.
I really wish the guy had been talking slower as he was giving out some VERY interesting stuff! I didn't have a pen handy so couldn't take notes. He did say that no way is 0 ohm suitable for beyer 'phones.... 120ohm is marginal but 200 - 250 ohm optimal for the most honest reproduction.
A most informative man and I'm only sorry I can't replicate everything he said here, he went into every detail (formulae, materials, impedance, mass, headphone enclosure types.... yikes! the lot, and at great speed)
Well worth phoning Beyer UK technical but have a pen and paper handy and expect to be on the phone for ages!!