[bland125]

You may be right. I saw a relationship between the hiss of the Odin and its low impedance, but maybe it is explained by high sensitivity instead? Welcoming others to chime in on this.

It certainly is likely less independent than I make it. I have never seen a 250ohm+ headphone hiss like a CA IEM for sure

On a different note, I have something I wanted to ask for a while and though a recommendation request, I feel LX current and past users are the best to ask. Here it goes:

I have been looking for an outdoor/sports wired set with a sound profile that align with the EE LX. I live in eastern Canada, winters are cold and humid and there is 0 chance I will use my sig setup outdoors or working out. Now there are lower cost alternatives from EE like the Bravado MK2 or FF Maestro mini maybe but still expensive for a Spotify EDM playlist to get me going further and faster only. I have a few TWS but comfort is less than ideal or then sound is when I find a comfortable one. I am following Facebook groups that likes the LX profiles aka bassheads but I know I will want to try em all and spend a fortune to get a $62 "best effort" results so thank you EE for the addiction that the LX feeds daily. Has anyone been able to find such thing? I have my eyes on a 7hz Legato for now for example of what seems decent enough.

Also, going all in today it seems (I rarely post): @Empire ears: a $250-$400, 1 DD, 1-2BA IEM EE style would probably be the first thing I ever pre-purchased so we can have a "gym" set that sounds like EE. 'Tis the season of wishes after all!

 

[nioh]

Also, going all in today it seems (I rarely post): @Empire ears: a $250-$400, 1 DD, 1-2BA IEM EE style would probably be the first thing I ever pre-purchased so we can have a "gym" set that sounds like EE. 'Tis the season of wishes after all!

You missed some zeroes there.

 

[Draxu]

You may be right. I saw a relationship between the hiss of the Odin and its low impedance, but maybe it is explained by high sensitivity instead? Welcoming others to chime in on this.

So for impedance in general, if you take the source/ouput of the amplifier as some AC voltage (can be DC too) the headphone + amplifier circuitry can be shown like this:

By using the phasor notation, jw (where w is frequency of voltage source, and j is denoting imaginary). The impedance of the headphone is:

Rh + jwL + 1/jwC​

While the amp has impedance:

Ro​

Treating this as a potential divider, we can write the second order system as follows:

Vi (1/jwC) / (R0 + Rh + jwL + 1/jwC) = Vo​

From this, we can get a ratio of Vi/Vo (voltage gain):

Vo/Vi = (1/jwC)/(R0 + Rh + jwL + 1/jwC)
Vo/Vi = 1/((jw)^2 LC + jw(R0 + Rh)C + 1)
[If you multiply by jwC]​

Take the magnitude of the ratio (how much output voltage we get from an input voltage/signal), this the GAIN:

|Vo/Vi| = 1/((1-w^2LC)^2 + (RC)^2)^1/2
​

Lower impedance, means you have greater gain, so less input voltage is needed to produce an equivalent output voltage compared to a higher impedance headphone. Though loudness itself may depend on sensitivity of the drivers themselves, this relates to their efficiency and is why specs like XXXdb per mW @ 1kHz exist.

Note: sensitivity is not dependant on impedance, impedance can be thought of how much power is delivered to earphones/headphones at some given level. While sensitivity is efficiency of transducers turning power into sound.

​

If you've been able to follow through the maths, you can draw a frequency response for the phase difference and gain |Vo/Vi|. Resonance happens near natural frequency depending on damping ratio (higher damping ratio, the further resonance happens from natrual frequency). The graph below however, only shows the variance of impedance with frequency (not |Vo/Vi]), but indicates a similar thing. I've borrowed a real measurement for the graph:

For the phase Bode plot on its own (Generalized example):
(the weird greek letter in the top right box is the damping ratio)

The frequency scale given is a ratio (driving frequency/natural frequency), at 10^0 (so at a ratio of 1), that is when the output source is at natural frequency w_o.

Some things to note:

• The voltage across headphones might be the same, but a higher impedance headphone always draws less current beause of Ohm's Law: I = V/Z (Z for impedance)
• Reactance (your 'imaginary' resistance from Capacitors and Inductors) varies with w, so that's why you can get varying impedance depending on the frequency of the source
• You can introduce low and high pass filters for rolling off the highs and lows
• You get a resonant peak that can be altered by changing R, L or C which in turn affects the damping ratio

High sensitivity earphones are better able to transfer electrial energy to kinetic energy (higher efficiency) so are more susceptible to signal noise from the amplifier. As they are usually low impediance, a higher current is drawn, so you'll get more crosstalk. Assuming the driving device is an op-amp or similar, the higher the quality of the amplifier the higher the Common Mode Rejection Ratio (CMRR) is, so you'll get a lower noisefloor.

Take some of the things with a grain of salt, this is more to give you a starting point (if interested). You can find better graphs for the plots.

Image credits:
https://lpsa.swarthmore.edu/Bode/underdamped/underdampedApprox.html

http://ohm-image.net/opinion/audiophile/2014/11/19/musings-on-headphone-amplifier-output-impedance#:~:text=Inner Fidelity: Musings on Headphone Amplifier Output Impedance,-November 19, 2014&text=Dr.,when fed low output impedances

https://www.soundstagesolo.com/index.php/features/181-how-to-read-our-headphone-measurements

 

[SoundFlow]

So for impedance in general, if you take the source/ouput of the amplifier as some AC voltage (can be DC too) the headphone + amplifier circuitry can be shown like this:


By using the phasor notation, jw (where w is frequency of voltage source, and j is denoting imaginary). You can write the second order system as follows:

Vi (1/jwC) /(R0 + Rh + jwL + 1/jwC) = Vo​

Basically the transfer function (i.e. what function maps Vo to Vi). From this, we can get a ratio of Vi/Vo (voltage gain):

Vo/Vi = (1/jwC)/(R0 + Rh + jwL + 1/jwC)
Vo/Vi = 1/((jw)^2 LC + jw(R0 + Rh)C + 1)
[If you multiply by jwC]​

Take the magnitude of the ratio (how much output voltage we get from an input voltage/signal), this is the magnitude of the impedance:

|Vo/Vi| = 1/((1-w^2LC)^2 + (RC)^2)^1/2
​

Lower impedance, means less source voltage need to produce an equivalent output voltage than a higher impedance headphone. Though loudness itself may depend on sensitivty of the drivers themselves. (This is why you get XXXdb per mW @ 1kHz)

​

If you've been able to follow through the maths, you can draw a frequency response for the phase difference and impedane |Vo/Vi|. Resonance happens near natural frequency depending on damping ratio (this depends on components):

)

For the phase plot on its own:
(the weird greek letter in the top right box is the damping ratio)


Also the fequency scale is a ratio, the actual frequencies vary with components.

Some things to note:
Reactance (your 'imaginary' resistance from Capacitors and Inductors) varies with w, so that's why you can get varying impedance depending on the frequency of the source
You can introduce low and high pass filters for rolling off the highs and lows
You get a resonant peak that can be altered by changing R, L or C which in turn affects the damping ratio

High sensitivity earphones might have been designed so that they pick up signal noise more easily from the amplifier. Assuming an op-amp or similar is being used, a better op-amp has better Common Mode Rejection Ratio (CMRR is higher) so it 'rejects' more noise for better equipment.

Take some of the things with a grain of salt, this is more to give you a starting point (if interested). You can find better graphs for the plots.

Image credits:
https://lpsa.swarthmore.edu/Bode/underdamped/underdampedApprox.html

http://ohm-image.net/opinion/audiophile/2014/11/19/musings-on-headphone-amplifier-output-impedance#:~:text=Inner Fidelity: Musings on Headphone Amplifier Output Impedance,-November 19, 2014&text=Dr.,when fed low output impedances

https://www.soundstagesolo.com/index.php/features/181-how-to-read-our-headphone-measurements

Awesome info. I’m generally well versed with this in the headphone space but it’s a much different transducer (for the most part) than what’s inside an IEM.

 

[javahut]

Awesome. Waiting on my Raven Standard Edition preorder going on 5 months now. Sent an email to Empire Ears support today to ask when they're gonna ship. Their office is closed until 1/2/2024.

This solidifies my vote for Raven being WORST FLAGSHIP IEM LAUNCH EVER.

What a huge FAIL. I've preordered the last 3 Empire Ears $3K+ IEM releases. They've ALL been released behind their stated release schedule. Each one has been further behind than the previous. Raven is now their "crown jewel" in later than stated release date. If I'd have known preorders wouldn't be released until there's ample stock at retailers anyway, I wouldn't have preordered. I won't be preordering another Empire Ears release.

WORST FLAGSHIP IEM LAUNCH EVER

 

[Hoegaardener70]

Awesome. Waiting on my Raven Standard Edition preorder going on 5 months now. Sent an email to Empire Ears support today to ask when they're gonna ship. Their office is closed until 1/2/2024.

This solidifies my vote for Raven being WORST FLAGSHIP IEM LAUNCH EVER.

What a huge FAIL. I've preordered the last 3 Empire Ears $3K+ IEM releases. They've ALL been released behind their stated release schedule. Each one has been further behind than the previous. Raven is now their "crown jewel" in later than stated release date. If I'd have known preorders wouldn't be released until there's ample stock at retailers anyway, I wouldn't have preordered. I won't be preordering another Empire Ears release.

WORST FLAGSHIP IEM LAUNCH EVER

I won’t preorder anything anymore, ever. No IEM, computer game, dap, you name it. Tired of being a guinea pig.

 

[bluestorm1992]

Kudos to the admin team.

 

[goatkidbaahcity]

Bizarre behavior from a full grown adult.

I enjoyed his hype posts when things were going well - just think that when people are 3.6k in the hole and only have 5 months of bonus waiting to show for it, it shouldn’t be that hard to have some sympathy for their frustrations.

Speaking of which - Jack pls I’m begging you, can we get another shot of the satin faceplates. I’ll even take another dimly lit bar picture so long as you add a second candle this time.

 

[xryptic]

Just picked up from my local distributor, stocks just arrived.

Posting images of the Satin Gold, do pardon the quality. Looks like the gold of my WM1ZM2 DAP, but colour looks slightly lighter and has a softer feel. It just looks amazing and hope it being matt rather than shiny wont scratch that easily.

 

[OneEyedHito]

Those look amazing. Satin is a beautiful touch.

 

[samuraix920]

The satin looks amazing, i wonder if my local store has the demo again

 

[ahossam]

Its crazy to think that all of this problematic product launch has claimed one of Head-Fi member, this could have been avoided if EE has good brand representative like Andy from Cayin.

 

[RonaldS86]

Just picked up from my local distributor, stocks just arrived.

Posting images of the Satin Gold, do pardon the quality. Looks like the gold of my WM1ZM2 DAP, but colour looks slightly lighter and has a softer feel. It just looks amazing and hope it being matt rather than shiny wont scratch that easily.

Is it just me or the faceplate looks like a cheap gold injection plastic
The satin black definitely looks better IMO

 

[SoundFlow]

Just picked up from my local distributor, stocks just arrived.

Posting images of the Satin Gold, do pardon the quality. Looks like the gold of my WM1ZM2 DAP, but colour looks slightly lighter and has a softer feel. It just looks amazing and hope it being matt rather than shiny wont scratch that easily.

Hmmm... Yes, definitely like the satin look over my shiny gold faceplates. I'd still say I prefer the look of satin black over all of them.

Either way it's good to see them arriving.

 

[HPLovecraft]

Is it just me or the faceplate looks like a cheap gold injection plastic
The satin black definitely looks better IMO

I agree. That looks like cheap plastic. This is taken from musicteck and looks a lot different!