Impedance question.

[Trevor B.]

I'm looking to buy a good pair of headphones for my home recording studio. The interface I use is an Apogee Quartet which has a 30 ohm headphone line out. My question is this; based on the 1/8 rule of impedance should I be looking at headphones with a 240 ohm rating?
The electronics of this stuff is Martian-speak to me so any help is greatly appreciated.

Trevor

[rick-slo]

IMO it's simple. Just go with Grado headphones (125, 225, 325 models are all great). I use them for listening and tweaking post recording. If you use the headphones during the actual recording though you probably want closed back headphones to not leak sound into the mikes - generally they won't sound as good though.

[Trevor B.]

Originally Posted by rick-slo

IMO it's simple. Just go with Grado headphones (125, 225, 325 models are all great). I use them for listening and tweaking post recording. If you use the headphones during the actual recording though you probably want closed back headphones to not leak sound into the mikes - generally they won't sound as good though.

Hey Rick,
Yes, I use headphones when recording. My space is small so I never turn on my monitors until my mikes are disconnected. I've been reading about Sennheiser HD6 Mix headphones and ATH - M50x. Both get rave reviews but the M50x headphones are low impedance so I'm trying to find out if that's a concern.

[Ty Ford]

Impedance does have some effect, but sensitivity does also.

I use Sony MDR 7506 because they are so sensitive.

They are not perfectly flat, but they are closed back and I've had some of them for 15 years.

Regards,

Ty Ford

[Trevor B.]

Originally Posted by rick-slo

IMO it's simple. Just go with Grado headphones (125, 225, 325 models are all great). I use them for listening and tweaking post recording. If you use the headphones during the actual recording though you probably want closed back headphones to not leak sound into the mikes - generally they won't sound as good though.

Originally Posted by Ty Ford

Impedance does have some effect, but sensitivity does also.

I use Sony MDR 7506 because they are so sensitive.

They are not perfectly flat, but they are closed back and I've had some of them for 15 years.

Regards,

Ty Ford

Thanks to both Rick and Ty for your input. Have to admit I'm still trying to understand the impedance equation i.e. will a higher impedance headphone equal more volume?

[donh]

Originally Posted by Trevor B.

Thanks to both Rick and Ty for your input. Have to admit I'm still trying to understand the impedance equation i.e. will a higher impedance headphone equal more volume?

nope. A proper mpedance match will get you a more linear transfer function between the amp section and the headphone element.

In the old days, to high an impedance on the load side would lead to amp instabilities but I'd like to hope those days are over. The general rule of thumb is that the driving impedance be 1/10th or less than the load. ie: a circuit designed for a 600-ohm load would be 60 ohms or less.

An amp has only so much voltage and current to throw at the load, so going really high in the load impedance eventually will drop your headroom.

From my sometimes headphone-obsessed friend Eric: "Sometimes manufacturers deliberately increase the resistance between the driver and the plug as a way of evening out or altering the effective impedance curve"

One more thing proving that everything is a tone control.

Bottom line with headphones: hook them up and listen. If they sound good to you they are good to you.
.

[Trevor B.]

Thanks, donh!