Why would Sennheiser sell ' identical' sounding and measuring headphones for a premium (HD650) when the only difference is the color scheme ?
They even go through the trouble of creating 2 different order codes for the driver assemblies (driver + baffle) that look the same.
Yes, I agree the HD600 (with used pads that are compressed a bit) sound the same as a HD650 with new pads.
The latest pads even have 1dB less bass.
They do not measure the same when fresh pads have been fitted nor do they sound exactly the same but are very similar.
HD600 vs
HD650 (both with fresh pads)
There also is a difference in distortion levels where the HD650 is slightly better.
The differences have been discussed ad nauseam in the first few pages.
The HD600 and HD650 Amir measured, most likely due to different pad conditions, do measure and sound the same so there is no reason to doubt Amir heard them the same. Below I overlaid Amirs HD650 and HD600 measurements. Maybe we can put this one to bed now ?
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