[wind30]

hi people,

I just got my 7250 today and I hooked it up to my dell studio 17 using USB. I can detect hissing with my UM2s through the headphone out of the 7520. Tried all five of my dell studio 17 usb ports and all have hissing.

I don't have a portable optical source to test it as the 7250 is in my office.

So is the hissing due to the 7250 or the usb source of my dell studio 17. Any solutions?

 

[LingLing1337]

It could be because of the low impedance/high sensitivity of the UM2s. Do you have any full-sized cans? If so, test them. I don't get any hiss with any of my headphones, including my Head-Direct RE2.

EDIT: Neither through USB nor optical.

 

[wind30]

no hissing with full sized cans but that is expected.

I have some sources that doesn't hiss with UM2 like tomahawk and my headphone out of TZ36 laptop so that makes the UM2 great of testing the noise floor of my stuff.

 

[1UP]

Hissing...could be the users on here who were still cheesed off with all their shills!

Sorry, facetious post.

 

[LingLing1337]

Quote:

Originally Posted by 1UP /img/forum/go_quote.gif Hissing...could be the users on here who were still cheesed off with all their shills! Sorry, facetious post.

...

Quote:

Originally Posted by wind30 /img/forum/go_quote.gif no hissing with full sized cans but that is expected. I have some sources that doesn't hiss with UM2 like tomahawk and my headphone out of TZ36 laptop so that makes the UM2 great of testing the noise floor of my stuff.

I believe the Tomahawk is made for IEMS, and I would say that the laptop HP out is just a really poor source in the first place. What are doing listening to IEMS thru a desktop system anyway? You ought to be rockin cans!

Either way you could add a "p to s" adapter to add resistance, which would probably reduce hissing.

 

[wind30]

I thought a well made amp should be hiss free even with iems.

I am not sure though if the hiss is coming from the computer or the dac or the power supply.

I noticed my local distributor gave me a switching mode power supply instead of the one shown on beresford website. could that be the cause?

 

[paara]

Which usb receiver chip is used in the Beresford TC-7520? BB27XX?

 

[.Sup]

Tried different power outlets? Both devices plugged in the same outlet? Try shielded USB cable.

 

[keyid]

Quote:

Originally Posted by 1UP /img/forum/go_quote.gif Hissing...could be the users on here who were still cheesed off with all their shills! Sorry, facetious post.

I suspected that guy but man the balls on him taken to another level.

 

[linuxworks]

Quote:

Originally Posted by wind30 /img/forum/go_quote.gif I thought a well made amp should be hiss free even with iems.

no.

its all about gains.

that's all it is. iem's need lower gain.

even a b22 will hiss if the gain is higher than it needs to be.

go inside and lower the actual gain (not just the input attenuator but the actual gain; if you can find the schematic).

everyone notices this. its all about matching gains. you never get away from that - never - no matter how much you spend

 

[linuxworks]

Quote:

Originally Posted by 1UP /img/forum/go_quote.gif Hissing...could be the users on here who were still cheesed off with all their shills!

not quite hissing; more of a raspberry sound, I believe.