High-Impedance Headphones and FM3

[carterscott]

Hopefully this question doesn’t kick off another round of discussion on the lack of headphone out on the current version of the FM3 that is shipping...

I own Beyerdynamic DT1990 headphones; I originally purchased them for use with a Kemper PowerHead. I didn’t bond with the Kemper and returned it, but loved the sound of the headphones.

I have an invite in hand for the FM3 and am debating between purchasing and waiting for the headphone version. Will the Beyerdynamics, which are high impedance at 250 ohm, work well with the headphone version of the FM3? If I need to buy a headphone amp anyway, that will make my decision for me!

Thanks in advance for the help!

 

[ax8guitarist]

I hadn't thought of that. I'm using the DT 880s through my Focusrite 18i8. If I can't use the headphones directly out of the FM3, that might change my mind, too.

 

[Barmaleus]

FM3 manual:
HEADPHONE OUTPUT
Connector: 1/4" stereo phone jack
Impedance: 35 Ω

Your headphones
Impedance: 250 Ω

Some internet search
https://www.headphonesty.com/2019/04/headphone-impedance-demystified/

"Pairing a headphone with an impedance of 2.5-8 times higher than the source impedance should yield good results. This recommended ratio is commonly known as the ‘rule of eighths’ and contributes to proper driver control (damping factor)."

250/35 = ~7.

Which means FM3 with a headphones out should drive your headphones just fine.

 

[carterscott]

Thank you for your reply! I did actually read that article before posting but didn’t find the relevant bit you did among all the technical discussion.

Looks like I’ll be joining many others in waiting for the headphones version. After a year of waiting for the FM3 to be available, I figure I can wait a little longer! (Although the longer the quarantine goes on, the less willpower I have to wait!)

Thanks again for the help!

 

[Barmaleus]

Welcome! =)
I don't know if we'll get non-headphone versions in Europe, but if we do, I will 100% wait for the one with the HP output.

I owned AX8 and while the extra cables and a small HP amp worked well, I did not like the idea of connecting extra stuff to such an advanced unit. Now that FM3 has the HP output, I will surely get the "full" version.