Sennheiser HD620S

[Gamemaker]

Depends what your using to drive them. As it happens they have a high sensitivity so don't need much voltage to hurt your eardrums. The high impedance means they won't be drawing much current either, I've used mine straight out of my LG V30 headphone jack.

Thanks. I’m using a Schiit Asgard 3 with a Loki Mini+ EQ. I’m assuming the Asgard will be able to drive them good enough. I guess I will give the HD620S a try.

 

[usern]

Asgard 3 has more than enough to drive them to excursion limits

 

[solderdude]

Looking to get a pair of these to replace my HD569s. Just would like to ask any owners how difficult are these to drive at 150ohms. I mainly use lower impedance headphones and am concerned about the higher impedance.Thanks

You will need 3V max to reach 120dB SPL.
Just played it uncomfortable loud and reached 5V and started to distort already.
so an amp that can reach 6V is already more than enough.
To get a feel of this for amps
6V in 32Ω = 1.2W rated amp, the Asgard 3 can supply 3.5W in 32Ω
6V in 300Ω = 120mW the Asgard 3 can supply 600mW in 300Ω
6V in 150Ω = 240mW he Asgard 3 can supply 1.2W in 300Ω
The HD620S is rated at 200mW continuous.

The HD620S is VERY easy to drive b.t.w. (112dB @ 1V) and draws very little current. Even a phone can drive them somewhat loud.

IF you were to accidentally turn up the volume on the Asgard 3 to max. level you will fry the HD620S and the SPL would momentarily be around 130dB (pain limit) so yeah... the Asgard 3 can drive it, need be in oblivion.. you just need an amp that can reach 100mW in 300Ω

 

[Bernard23]

Re volume. I'm using them with an LG V30 (which has a high impedance higher output mode) and an S23 thru a Hidisz Martha dongle, and comparing them to the SRH840A and they're noticeably quieter at the same vol. The Senns are more sensitive, something like 102 v 97 dB/mW but 140 v 30 ohms (irrc). I wasn't expecting as big a difference tbh. I guess at say 2V that's 14mW vs 66mW which is what, around 6dB in power input. Not sure how you translate that into SPL at their respective sensitivities.
Either way both devices have enough headroom, though you'll not be able to deafen yourself with an LG phone.

Enough of numbers for a moment. I've tweaked the EQ slightly, to bring the sub bass up a bit and they sound very good indeed. I'm impressed how wide the sound stage is, but also how much detail there is. They're just fun to listen to, like good hardware you stop noticing it's there and just get wowed by the music. Right now I'm reminiscing how brilliant Paul Kossof was.

 

[Gamemaker]

You will need 3V max to reach 120dB SPL.
Just played it uncomfortable loud and reached 5V and started to distort already.
so an amp that can reach 6V is already more than enough.
To get a feel of this for amps
6V in 32Ω = 1.2W rated amp, the Asgard 3 can supply 3.5W in 32Ω
6V in 300Ω = 120mW the Asgard 3 can supply 600mW in 300Ω
6V in 150Ω = 240mW he Asgard 3 can supply 1.2W in 300Ω
The HD620S is rated at 200mW continuous.

The HD620S is VERY easy to drive b.t.w. (112dB @ 1V) and draws very little current. Even a phone can drive them somewhat loud.

IF you were to accidentally turn up the volume on the Asgard 3 to max. level you will fry the HD620S and the SPL would momentarily be around 130dB (pain limit) so yeah... the Asgard 3 can drive it, need be in oblivion.. you just need an amp that can reach 100mW in 300Ω

Thank You very much for all this information.

 

[solderdude]

Re volume. I'm using them with an LG V30 (which has a high impedance higher output mode) and an S23 thru a Hidisz Martha dongle, and comparing them to the SRH840A and they're noticeably quieter at the same vol. The Senns are more sensitive, something like 102 v 97 dB/mW but 140 v 30 ohms (irrc). I wasn't expecting as big a difference tbh. I guess at say 2V that's 14mW vs 66mW which is what, around 6dB in power input. Not sure how you translate that into SPL at their respective sensitivities.
Either way both devices have enough headroom, though you'll not be able to deafen yourself with an LG phone.

Enough of numbers for a moment. I've tweaked the EQ slightly, to bring the sub bass up a bit and they sound very good indeed. I'm impressed how wide the sound stage is, but also how much detail there is. They're just fun to listen to, like good hardware you stop noticing it's there and just get wowed by the music. Right now I'm reminiscing how brilliant Paul Kossof was.

You can't compare dBmW numbers directly because the impedance differs between the headphones. You can, however, directly compare dBV numbers (well sort-off).
HD620S = 112dBV
SRH840A = 116dBV
So at the same volume control position the SRH840A is about 4dB louder (is just a little louder). This is skewed a bit for one's perception because of the difference in tonal balance between the headphones.
My dBV measurements are not done at a fixed frequency but for 'overall' tonal balance level so might differ a bit from manufacturer numbers which often are incorrect anyway.
On the HD620S box they are (were by now as the box and manual mentioned 105dBV instead of 110dBV?)

 

[Bernard23]

4dB feels about right when I play around with the volume.
I'm tempted to get the Fiio KA17 dongle anyway, which would eliminate any problems of insufficient power.

 

[sharock]

These are currently discounted to £206.40 on Sennhesier's UK shop. Tempting but potential for not getting a good seal around the jaw puts me off.