[spanks]

I don't believe its in the recording, so is there anything that can cause a hiss in the treble? Is it an inherent trait of some cans?

I returned my sr225's and am looking for other options, thinking about some dt 990's. I am back to my hd 555's for the moment. The hd-555's obviously don't do treble as well, and this hiss is something I've noticed after going back to them.

Just curious, thanks

 

[b0dhi]

Could be the amp. Or the source. Or a noisy power supply somewhere. Ultimately though, it's dying stars

 

[epaludo]

I noticed that the background hiss in my portable setup went away when i upgraded my portable amp from a PAV2V2 to a Hornet "M". Definitely the hiss in all gone. Nothing at all ...

 

[kramer5150]

impedance mismatch between amp circuit and cans. Gain of amp circuit is too high for that impedance load.

 

[spanks]

If its hardware related I'm guessing its coming from my crappy logitech 2.1 sub

Its only audible when the music is really quiet/only treblely stuff...so the beginning of songs and stuff.

My headphones are running from X-fi to sub, from volume control thing to my heapdhones...after I gets some free time I'll finish my cmoy and throw away these damn speakers

Thanks for the replies, I had read mention of it earlier somewhere and now that I have experienced it I was curious

 

[Zorander]

The headphone jack, alias amp, is the culprit. Low-impedance cans, including Grados, are susceptible to hiss for reasons given by Kramer. You need to use a different amp or go with a higher-impedance phone.

Cheers!

 

[holland]

Or use an inline volume control to present a higher load (Radio Shack has some that you stick between your mp3 player and the headphones). You can make your own without a potentiometer using a voltage divider with a parallel and series resister.

http://en.wikipedia.org/wiki/Voltage_divider

If using an amp with selectable gain through a switch, lower the gain.

 

[Chris_Himself]

its the sound of the lifestream. (ff7 nerds)

 

[Assorted]

Since it's a related topic, I have a question. If I know at what position the dial is on a volume attenuator, is there anyway to measure it's impedance? I want to do this so that I can have an impedance adaptor made to minimize quality loss.

 

[spanks]

Quote:

Originally Posted by Assorted /img/forum/go_quote.gif Since it's a related topic, I have a question. If I know at what position the dial is on a volume attenuator, is there anyway to measure it's impedance? I want to do this so that I can have an impedance adaptor made to minimize quality loss.

If I understand correctly you want to take out the volume control and fix the volume level?

That sounds like a good plan, except you can only really use it with one set of cans. Listening volume on my grados would probably have blown my ears out listening at the same level with my senns.

 

[kramer5150]

Quote:

Originally Posted by Assorted /img/forum/go_quote.gif Since it's a related topic, I have a question. If I know at what position the dial is on a volume attenuator, is there anyway to measure it's impedance? I want to do this so that I can have an impedance adaptor made to minimize quality loss.

Its not that easy to measure impedance... some of this is based on things I have heard/read, so please correct me if I ma off base.

You need a signal source (a fixed frequency test tone I believe).

some sort of "load", and I say that in parenthesis because I don't know if a headphone by itself plugged into the circuit is the only thing thats needed.

My understanding is that the compressible volume of air between the driver diaphragm and listener's ear has a slight impact on system impedance. So measuring headphone impedance off the head can be different than when measured on the head. Fortunately we all have a head... no need to go out and buy a dedicated head for this purpose.

Finally you need a scope to plot impedance values across the audible spectrum.

So... I don't think its as easy as measuring coil resistance with a multi-meter.

 

[Assorted]

Quote:

Originally Posted by kramer5150 /img/forum/go_quote.gif Its not that easy to measure impedance... some of this is based on things I have heard/read, so please correct me if I ma off base. You need a signal source (a fixed frequency test tone I believe). some sort of "load", and I say that in parenthesis because I don't know if a headphone by itself plugged into the circuit is the only thing thats needed. My understanding is that the compressible volume of air between the driver diaphragm and listener's ear has a slight impact on system impedance. So measuring headphone impedance off the head can be different than when measured on the head. Finally you need a scope to plot impedance values across the audible spectrum. So... I don't think its as easy as measuring coil resistance with a multi-meter.

I see, thank you for your response.

 

[holland]

You can measure the potentiometer. It won't be 100% accurate, but you don't need it to be. You can see how the potentiometer (volume control) is modeled as a voltage divider.

Also, do a search on "hissbuster" on these forums.

http://en.wikipedia.org/wiki/Potentiometer

 

[b0dhi]

Quote:

Originally Posted by Assorted /img/forum/go_quote.gif Since it's a related topic, I have a question. If I know at what position the dial is on a volume attenuator, is there anyway to measure it's impedance? I want to do this so that I can have an impedance adaptor made to minimize quality loss.

Because a volume attenuator is a purely resistive load (ideally), it's actually not an impedance (impedances have phase). All you need to do is use a DMM and measure the resistance across it, and use the same resistance in the fixed attenuator you want to make.

 

[reorx]

better to ask in this HISS thread than post a new thread...

in my case,there is no hiss thrugh my go-vibes, but when i turn the volume knob, i notice hiss that eventually decereases as i continually turn the knob. But once i turn the amp on again, and i adjust the volume knob, there is hiss again. It happens no matter what phones i use (sr60, k81dj, x3). Its really no biggie since once the volume is set and the music is playing, no hiss, but only when i adjust the knob the hiss re appears. Is this normal for all amps (my first amp, unfortuantely) or is there something wrong?