Love the Airhead cross-feed, but...

[Honus]

The Airhead generates a fair level fo "hiss". Would the PortaCorda do the same and is the cross-feed affect similar to Headroom's cross-feed?

 

[TheSloth]

What headphones are you using? Are you using AC power or batteries? You can always add a small resistor to increase the impedence, assuming you like the sound afterwards.

Or, you could cure the problem with a HeadRoom Micro instead. No hiss there...

 

[Honus]

Using UE Superfi 5 Pros - running on bats. I see you have the same phones. Do you get hissing with you total bithead? How do I go about implementing the resistor?

Thanks!

 

[kendrid]

I had a bithead and it hissed with my ER4p headphones. I end up returning it.

A few months later I found a post here about hissing and a 'fix' for it. Try searching and maybe you will find it. If I remember correctly the tech guy from Headroom post the solution. I'd try to contact him before returning it. I really liked it minus that issue. I should have tried their tech support first.

 

[TheSloth]

The dual driver Super.fi's are perfect for adding a resistor - as their is a crossover, the frequency response shouldn't be obviously effected. You can get a DIY'er to build you a simple one, or you could use the etymotic p/s converter cable, which is a 75 ohm resistor.

I'm not aware that there is a 'fix' for the mobile line. The hiss is the noise floor of the amplifier, created by various factors including the opamps and components on the board. I'm not sure that there are any amps in that price range, or that size constraint that would be silent with very low impedence headphones. If you like the sound otherwise, I strongy recommend the resistor approach. That's in fact what the 'attenuator' that comes with the Super.Fi's does, but it attenuates way too much to be useful for anything other than hearing protection when connected to an unknown source.

 

[Honus]

Thanks folks! I called Headroom today, and they suggested using the attenuator. If that's too much, I might look into the Ety solution. I know there are better amps out there, but I think the cross-feed circuitry is great in this little amp. I have the Xinfeed adaptor, and IMHO the Headroom circuit is much better.

Again, thank you all for the input.

 

[arielext]

I bought a second hand airhead, but due to the hissing on my ES2's I ended up trying/buying the porta corda III. The corda has no hiss but (I'm guessing here) the usb circuit is making some noise, like repeated scratches. With help of the ER4p/s adapter I can filter out that noise to a real minimum, but maybe I need to replace the adapter by a 120 ohm resistor.

 

[Skylab]

Quote:

Originally Posted by Honus The Airhead generates a fair level fo "hiss". Would the PortaCorda do the same and is the cross-feed affect similar to Headroom's cross-feed?

I had a Total Airhead, and agree it was noisy. I bought a Meier Porta Corda Mk III (no USB) and it is dead quiet. It's much more transparent, and quieter, than the Airhead IMO.

The Xin Supermacro 3 V6 is also very quiet and transparent, and has some great features (bass boost, crossfeed, gain settings, etc), but it is more expensive than the TA or PCIII.