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Posts by jcx

cables for electrostats are special - the cable even with special construction, foamed dielectric still accounts for ~30% of the C load your amp has to drive   also with some project amps having more stored energy in their supplies than defibrillators it is good to see double/reinforced insulation for the  volts
if your profile location is correct http://www.chattlab.org/blog/about/  looks from the web like they're still alive, should have people with tools, skilz   you may have missed closing RadioShack parts being sold off by the pound - Digikey is convenient, stocks real parts
you can build circuits which are 1st order temperature sensitive - and you do need to wait for them to stabilize to operating temp - 1st 10 minutes gets most equipment close to steady state - certainly anything of reasonable construction and desktop size is as warm as it is going to get in an hour - of course that is a delta over the room/air temp and will change as the external temp varies   you can see warmup/drift specs for serious measurement equipment - but DC...
the Smyth SVS Realizer has been on headfiers heads for 7 or so years now -  waiting for new tech not necessary   there have been other serious hrtf simulation products - some at least made it into pro studios - this isn't completely new or unknown   the academic research, demos go back even farther - the limit hasn't been knowledge for quite a while now     waiting for cheap head tracking personalized hrtf virtualization tech however may continue
 really doubt anything being measured will show a unambiguous trend - otherwise the cause would be well known to EE who build much more sophisticated critical and scrutinized Industrial Scientific and Medical instrumentation   such designers do know about some capacitor dielectric changes with bias and time, some semis and other component do stress relive with mild thermal cycles - but the effects where known aren't big at audio frequencies     and if you are a guru...
the pre/post ringing is Gibbs Phenomena - a mathematical consequence of wanting steep filter slope to have 20 kHz flat response and attenuate 24 kHz image by 96 dB for 16/44 CD digital audio   the time domain overshoot/ringing can be moved around with "apodizing filters" to avoid the pre-ringing but then doubles it up in post ringing: https://www.ayre.com/pdf/Ayre_MP_White_Paper.pdf   Mike has ruled out the slower filter roll off that Ayer uses from his comment on...
Smyth's SVS Realizer is well known, has been demoed at national meets - really works - head tracking in particular is important for front/back disambiguation with small turning of your head - just like you do all the time with real sounds   http://www.smyth-research.com/technology.html   if you haven't heard the SVS Realizer with personalized calibration in a multichannel setup you simply don't have any basis to comment on what can't be done
cable can be significant too ~100-200 pF range should cover most ES headphones+cable at the amp end   C load is a problem for some negative feedback amps - has to be included in design considerations for ES amps     likely channel imbalance is due to electrical leakage draining one side diaphragm charge more than the other or diaphragm tension mismatch could have some effect   but you could lose a stator drive signal from a broken wire or amp and still get audio...
I'd still guess the underlying mechanical diaphragm drumhead resonance was low bass but I don't know, possibly it could be higher with circumaural headphones only driving a smallish mostly sealed cavity     couldn't see a low bump even in the couple of high res impedance plots at http://www.innerfidelity.com/headphone-data-sheet-downloads that I looked at - maybe looking at more would give a hint
the planar conductor does have low inductance - but there is still mass-spring resonance in any driver which is reflected to the electrical terminals by the electro-acoustic properties of the "motor" and mass and suspension of moving parts   for electrodynamics there should still be the mass-spring resonance of the diaphragm but it isn't as easily visible at the electrical terminals in part because of the poor efficiency of most Orthos as electric "motors"   and the...
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