[jasonb]

If you can, also try it on another source. One that is lower output impedance. The Timeless are only 14ohm impedance (and are also pretty sensitive @104dB/mW). While that isn't horrid, it may just be the source that is at fault here.

Are you listening to them at a loud level when this happens?

Is it 104 at 1mw, or 104 at 1 volt?

 

[samandhi]

Is it 104 at 1mw, or 104 at 1 volt?

Sorry that was a typo... It should 104dB/mV...

 

[jasonb]

Sorry that was a typo... It should 104dB/mV...

Pretty sure it’s 104 at 1 volt, not 1mV. Or maybe 100mV. Idk anymore. All I know is that the Qudelix app has a section where you can put the impedance and sensitivity in and it tells you the SPL. When putting 104 in on the Qudelix app it definitely doesn’t give the correct SPL value.

 

[samandhi]

Pretty sure it’s 104 at 1 volt, not 1mV.

Headphone sensitivity is also expressed in dB/mV or decibel per unit of millivolt. Power is the product of voltage(V) and current (I), as defined by the following equation.

P = I x V

Often, there’s a slight difference between measurements in dB/mV and dB/mW as the latter needs to take account of the current of the audio signal.

Most manufacturers will use dB/mW to measure headphone sensitivity as it takes into account both current and voltage delivered.

As seen on here:
https://soundslack.com/headphone-se...or,account of the current of the audio signal.

 

[jasonb]

As seen on here:
https://soundslack.com/headphone-sensitivity-explained/#:~:text=Headphone sensitivity is also expressed in dB/mV or,account of the current of the audio signal.

Well that doesn’t seem right either.

At my normal listening volume I’m using 8mV according to the Qudelix app. So 104 at 1mV doesn’t make sense either.

I really don’t know. All I know is that when using my AirPods Pro 2, I listen in the 58-62ish dB area. And I listen to all of my headphones at a similar level.

 

[samandhi]

Pretty sure it’s 104 at 1 volt, not 1mV. Or maybe 100mV. Idk anymore. All I know is that the Qudelix app has a section where you can put the impedance and sensitivity in and it tells you the SPL. When putting 104 in on the Qudelix app it definitely doesn’t give the correct SPL value.

The problem with that app is there is not enough information input to actually tell the SPL. You would also need to know the power that is applied at any given time to know this.

 

[jasonb]

The problem with that app is there is not enough information input to actually tell the SPL. You would also need to know the power that is applied at any given time to know this.

I’d imagine it knows all this. It’s taking how loud the music is relative to “0” and doing the math based on how much power it’s putting out at whatever volume and the impedance and sensitivity of the headphones.

 

[samandhi]

Well that doesn’t seem right either.


At my normal listening volume I’m using 8mV according to the Qudelix app. So 104 at 1mV doesn’t make sense either.

I really don’t know. All I know is that when using my AirPods Pro 2, I listen in the 58-62ish dB area. And I listen to all of my headphones at a similar level.

That sounds correct.

For the Timeless (OG) if normal listening level is something like 80dB (as an example, since we don't know the dB level at which you consider normal listening levels) the Timeless require:

• 1mW
• .12VRMS
• 8.5mA

Edit: Apologies, I missed the last part where you specified the dB at which you normally listen.

 

[jasonb]

That sounds correct.

For the Timeless (OG) if normal listening level is something like 80dB (as an example, since we don't know the dB level at which you consider normal listening levels) the Timeless require:

• 1mW
• .12VRMS
• 8.5mA

“.12VRMS” is 120mV

That sounds correct.

For the Timeless (OG) if normal listening level is something like 80dB (as an example, since we don't know the dB level at which you consider normal listening levels) the Timeless require:

• 1mW
• .12VRMS
• 8.5mA

Edit: Apologies, I missed the last part where you specified the dB at which you normally listen.

So you’re saying the Timeless should be at 80dB at 1mW?

 

[samandhi]

“.12VRMS” is 120mV

So you’re saying the Timeless should be at 80dB at 1mW?

I'm saying that it only takes 1mW, and 8.5mA to drive them to 80dB.

 

[jasonb]

I'm saying that it only takes 1mW, and 8.5mA to drive them to 80dB.

So the spec 7Hz lists as 104dB is what? 1 volt? I always sucked at math, but the numbers aren’t adding up to me.

 

[holsen]

I was an early, frequent and enthusiastic contributor on this thread and still love the Timeless, my 7th and one of my favorite planars of all time but now it's time to let this set go as I explore deeper into planarworld. My set is up for sale with seriously upgraded cable. The Stock Cable was a choke point (looked nice) so I sold it as part of a lot and so my timeless will come with 4.4mm 8 Core (4 Core Pure Silver / 4 Core Pure Copper) Litz hybrid. PM if interested. It'll be hitting the classifieds in a couple of hours.

 

[samandhi]

So the spec 7Hz lists as 104dB is what? 1 volt? I always sucked at math, but the numbers aren’t adding up to me.

It is either mW or mV. Most manufacturers give the sensitivity in mW because it takes into account both voltage and current. So most likely my OG post was correct at 104dB/mW, but it WAS a typo as I meant to type mV...

 

[jasonb]

It is either mW or mV. Most manufacturers give the sensitivity in mW because it takes into account both voltage and current. So most likely my OG post was correct at 104dB/mW, but it WAS a typo as I meant to type mV...

These numbers still don’t add up to me, but ok.

 

[samandhi]

Most people don't realize that it doesn't take as much power to push head gear as is professed by some. For instance, for some 300ohm headphones with a 102dB/mW sensitivity, you really only need (to reach a whopping 110dBSPL):

• 7mW
• 1.45VRMS
• 4.8mA

Now, this doesn't account for the voltage swing that you would get (at differing frequencies) and remember with planars the voltage doesn't swing up or down, it the is the current that swings (the opposite of DD, where current draw is steady). Also, keep in mind that this only means that you can drive them to that dB level. It doesn't mean they will sound good or bad. These are calculations on paper, and IRL they might be slightly different.