[Gazza]

 
I would be very careful with the volume knob. That amp is at least 3 times more power than you need.
 
if you have a spl meter, definitely keep the peaks under 95db.
 
The stax extension cable i have here (one of the old ones) measures at about 35pf. So about 1/3 the load of a set of headphones.

 
The Densen uses a high-precision 200-step attenuator in 0.5 dB steps which gives me precise control so I'm really careful with it. Of the 200 steps I normally keep the volume at 115-125 step mark. I don't have a SPL meter but I should probably buy one to try what you've suggested. 
 
Thanks for your feedback.

 

[mulder01]

That sounds so weird... I don't really know how the Stax phones in particular work, but the length of the cable should be almost irrelevant if you're measuring capacitive reactance because it is dictated by the distance between the conductors and the type of material in between them rather than the length of the conductors, right?
 
Like on a 75ohm coax cable, the impedance (which is mostly capacitive reactance) is 75ohms.  If that cable is 10m long, it's 75ohms, cut the cable in half and measure each half, they are both 75ohms.  Do a good job of joining five 10m pieces of 75ohm coax together and measure it and it will be 75ohms.  So the impedance of the cable stays the same regardless of length.
 
Am I missing something with the stax cable?

 

[JimL11]

Yes, you are missing something.  You are confusing cable capacitance with characteristic cable impedance.  Leaving out resistance for a minute, any length of cable has both a capacitance and an inductance.  
 
A 75 ohm cable has its inductance and capacitance balanced in such a way that its impedance is RESISTIVE to AC signals.  If you double the length of the cable, the capacitance DOUBLES, but so does the inductance so they continue to balance regardless of length.  The 75 ohms does NOT refer to the capacitance of the cable, which increases proportional to its length.  If you want a more technical discussion, take a look at the Wikipedia article on coaxial cables, specifically under the section on Derived Electrical Parameters.

 

[Jones Bob]

I don't have a SPL meter but I should probably buy one to try what you've suggested. 

There are SPL apps for your smartphone.

 

[mulder01]

  Yes, you are missing something.  You are confusing cable capacitance with characteristic cable impedance.  Leaving out resistance for a minute, any length of cable has both a capacitance and an inductance.  
 
A 75 ohm cable has its inductance and capacitance balanced in such a way that its impedance is RESISTIVE to AC signals.  If you double the length of the cable, the capacitance DOUBLES, but so does the inductance so they continue to balance regardless of length.  The 75 ohms does NOT refer to the capacitance of the cable, which increases proportional to its length.  If you want a more technical discussion, take a look at the Wikipedia article on coaxial cables, specifically under the section on Derived Electrical Parameters.

 
Hmm, that doesn't really explain anything though. Like you say, probably not the right place for this discussion.  
 
If people claim to hear a difference with the extension cable then we'll leave it at that.  I haven't tried it.

 

[Quixote79]

   
Hmm, that doesn't really explain anything though. Like you say, probably not the right place for this discussion.  
 
If people claim to hear a difference with the extension cable then we'll leave it at that.  I haven't tried it.

not make sense coax resistive to ac it sure conduct ac well
me think he confuses resistance and capitance
ohms never be unit of capitance its faraday

 

[Gazza]

There are SPL apps for your smartphone.

 
That's a great suggestion. Just did a quick test and getting results in the mid eighties for my higher listening levels. Pretty good.

 

[kevin gilmore]

So open up your books on transmission line theory

The stax extension cable has a characteristic impedance of 125 ohms
The source impedance of the amp had better be 5.1k ohms (or more)
The load is a varying imaginary impedance between j1M ohm and j20k ohm
The system cannot operate like a transmission line!

Since the extension cable is a signifcant percentage of the load, It will absolutely
Have an effect.

 

[VandyMan]

Since the extension cable is a signifcant percentage of the load, It will absolutely
Have an effect.

The question is how audible an effect. Obviously, that will depend on the cable and the amplifier. Personally, I don't hear any obvious difference using the BHSE and the STAX SRE-950S cable. Others apparently do.

 

[mulder01]

 
not make sense coax resistive to ac it sure conduct ac well
me think he confuses resistance and capitance
ohms never be unit of capitance its faraday

 
Unit of capacitance is correct.  Capacitance causes capacitive reactance which contributes to impedance.

 

[jibzilla]

 
The question is how audible an effect. Obviously, that will depend on the cable and the amplifier. Personally, I don't hear any obvious difference using the BHSE and the STAX SRE-950S cable. Others apparently do.

 
There is no getting around that Kevin is right about this. At the same time it does not surprise me that you find the differences to be very subtle. Even at 009/BHSE levels. For me I have always found headphone cable extensions/aftermarket cables to be very subtle. The only headphone where I found cables to make a noticeable difference is sort of ironic in the hd800 as it comes with a nice stock cable imo.
 
Where you will find noticeable to night and day differences is in TT's. Here in the U.S. you will see allot of isonoe feet($200) and ginko cloud platforms($400) underneath TT's. In Japan you will see the TT's in a totally separate room with long runs of high quality, low capacitance cables. This cable is not cheap but still a 20ft. run will only set you back $200 and provide more isolation than the $600 worth of gadgets I mentioned earlier, at least with speakers. Skimp on the long cable run though and there will be a very noticeable degradation. If I'm not mistaken there were some TT's that had adjustable capacitance. 

 

[JimL11]

   
Hmm, that doesn't really explain anything though. Like you say, probably not the right place for this discussion.  
 
If people claim to hear a difference with the extension cable then we'll leave it at that.  I haven't tried it.

Sigh.  One more time.  A cable's characteristic impedance (e.g. 75 ohm or 50 ohm) only applies when you're dealing with transmission lines.  Specifically, it only applies when the "transmitter" and "receiver" have the same impedance.  For example, in FM radio, the antenna has a characteristic impedance of 75 ohms, and the FM receiver also has an impedance of 75 ohms.  Then, if the cable also has a characteristic impedance of 75 ohms, the signal will go from antenna into receiver without any reflections.  Reflections are bad because they bodge up the signal.  The same is true in carrying digital signals from a CD transport to the DAC, you don't want reflections.  The transport output impedance is 75 ohms, the cable should be 75 ohms, and the DAC input is 75 ohms.
 
However, in the case of a headphone, the amplifier has an output impedance of at least 5.1 kilohms (at least in KGs and my designs), the headphone has an impedance that varies dramatically because it looks kinda like a capacitor, so you can't use transmission line theory.  In this case, the capacitance of the extension cable adds to the capacitance of the headphones, making a bigger load which is harder to drive.  Whether you can hear the difference or not depends in part on how tolerant of the bigger load the amplifier is.  
 
If this isn't enough of an explanation, then you need to go do some homework in basic electronics and physics, because there isn't another explanation.

 

[VandyMan]

   
There is no getting around that Kevin is right about this....  The only headphone where I found cables to make a noticeable difference is sort of ironic in the hd800 as it comes with a nice stock cable imo.

 
I did not disagree with Kevin. He said nothing about *hearing* the difference between using a quality extension cable and not using one. Differences you believe you hear with an HD-800 cable have nothing to do with electrostatics. 

 

[jibzilla]

   
I did not disagree with Kevin. He said nothing about *hearing* the difference between using a quality extension cable and not using one. Differences you believe you hear with an HD-800 cable have nothing to do with electrostatics. 

cool

 

[vapman]

Do we have any fans of the SR-003 here? I have had my eyes on it for a very long time. But I don't know enough about it to know if I should bite. do they go in as far as IEMs or are they more shallow? I'd prefer it to be like an earbud but I'm still interested.