The Beyerdynamic DT880 Discussion thread
May 7, 2014 at 10:32 PM Post #7,321 of 12,546
Nah, just around $300. (Darkvoice 336
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Or a Matrix M Stage.
Or a $120 FiiO E09K.
 
Because we love to "discuss" amp power,
I ran some numbers on the various impedances of DT880 to show current draw and voltage needed for various power levels. 
 
32 Ohm Versions   (note: Innerfidelity specs the efficiency as 0.47 mW = 90 dB SPL)
1 mW = 179 mV, 5.6 mA
5 mW = 400 mV, 12.5 mA
10 mW = 565 mV, 17.6 mA
25 mW = 935 mV, 27.9 mA
100 mW = 1.79 V, 55.9 mA
 
250 Ohm versions   (note: Innerfidelity specs the efficiency as 0.38 mW = 90 dB SPL)
1 mW = 500 mV, 2.0 mA
5 mW = 1.12 V, 4.4 mA
10 mW = 1.58 V, 6.3 mA
25 mW = 2.5 V, 10.0 mA
100 mW = 5.0 V, 20.0 mA
 
600 Ohm versions   (note: Innerfidelity specs the efficiency as 0.43 mW = 90 dB SPL)
1 mW = 775 mV, 1.29 mA
5 mW = 1.73 V, 2.89 mA
10 mW = 2.45 V, 4.0 mA
25 mW = 3.87 V, 6.5 mA
100 mW = 7.74 V, 12.9 mA
 
May 7, 2014 at 10:53 PM Post #7,322 of 12,546
My Grado SR 80I's sound pretty good with the Vali.  The DT 880 600 Ohm don't sound as good as I hoped.  Maybe the amp doesn't match well?  The bass isn't there like the Grado's and they highs are almost too much.  I hope burn in helps and maybe I should plan another amp to properly run them to their potential?

Maybe I'm used to less fidelity?  

Lower volume seems better.  I'll give them several hours before I complain too much, but right now, they are bright.


Well, the DT880 has always been fairly bright. Someone posted a frequency response before and after burn in, and it didn't really change much for the DT880, so I don't suppose you'll see much of a change.

To be fair, though, the DT880 does sound pretty good at low volume, or with recordings where that peak in the treble can be tolerated. But otherwise, I think you should look beyond the Vali if you are looking to "bend" the sound. And there is no shame in "bending" the sound, by the way. Contrary to popular "misbelief."

Maybe they need a $500+ amp to sound good, Bill-P. :tongue_smile:


Well, or just something that costs more than $129?

Vali is a good amp where power requirement is not a problem. It's one of those things that can undermine an amp's performance.

But actually the DT880 @600 Ohms only need 0.40mW to reach 90dB, so vali would do pretty well.

--edit: dB value corrected.


Yep! It turns out the DT880 does need a surprising amount of power for full dynamic range, right? In fact, that rightly exceeds its specifications since the drivers are only guaranteed to perform right with a max load of 100mW.

So each jump in dB is quite a big jump in power, which is probably why they recommend a 5W per channel amp for the HE-6's.


Yep! Sensitivity turns out to be a bigger factor of power requirement than the impedance. And that's why even the 32 Ohm Beyers may need an amplifier to "sound its best."
 
May 8, 2014 at 12:16 AM Post #7,323 of 12,546
I have been getting massive headaches from my DT880 Pro slipping down and putting a lot of pressure on the top of my head.  So I decided to try out something that I saw in the LCD2 thread, I sewed up an elastic sock (as my initial test) that I attached to the half circle metal parts to use as a new band.
 
After a little adjusting, my head is half an inch from my head to the headphone band.  Now I can honestly say that it is the most comfortable headphone that I have ever tried. With something so simple, it's incredulously more comfortable.
 
May 8, 2014 at 1:08 AM Post #7,324 of 12,546
  I have been getting massive headaches from my DT880 Pro slipping down and putting a lot of pressure on the top of my head.  So I decided to try out something that I saw in the LCD2 thread, I sewed up an elastic sock (as my initial test) that I attached to the half circle metal parts to use as a new band.
 
After a little adjusting, my head is half an inch from my head to the headphone band.  Now I can honestly say that it is the most comfortable headphone that I have ever tried. With something so simple, it's incredulously more comfortable.


Any chance you could post a picture or link to where you saw that? I have the same problem with my dt880 and never got any use to them due to clamping(also tried to stretch it out). edit: never mind, i got the general idea. will try it out tomorrow 
 
May 8, 2014 at 3:28 AM Post #7,325 of 12,546
Well, the DT880 has always been fairly bright. Someone posted a frequency response before and after burn in, and it didn't really change much for the DT880, so I don't suppose you'll see much of a change.

To be fair, though, the DT880 does sound pretty good at low volume, or with recordings where that peak in the treble can be tolerated. But otherwise, I think you should look beyond the Vali if you are looking to "bend" the sound. And there is no shame in "bending" the sound, by the way. Contrary to popular "misbelief."
Well, or just something that costs more than $129?

Vali is a good amp where power requirement is not a problem. It's one of those things that can undermine an amp's performance.
Yep! It turns out the DT880 does need a surprising amount of power for full dynamic range, right? In fact, that rightly exceeds its specifications since the drivers are only guaranteed to perform right with a max load of 100mW.
Yep! Sensitivity turns out to be a bigger factor of power requirement than the impedance. And that's why even the 32 Ohm Beyers may need an amplifier to "sound its best."


Beyer's spec is closer to do not exceed 100 mW if you don't want to burn your headphones down.
600 Ohm DT880 kind of, sort of work OK from a wee little FiiO E17 if you set the gain at +12 dB.
Maximum output of the E17 is approx. 2 Vrms.
 
May 8, 2014 at 3:33 AM Post #7,326 of 12,546
If you're willing to sacrifice the larger soundstage of the DT880, the Alpha Dogs are incredible headphones and they do vocal imaging way better than the DT880s as well as the liquid midrange and rumbling  bass.
 
DT880s have more bass impact on some songs but don't reach the sub bass levels of the Alpha Dogs.
 
Alpha Dogs are like 5% less bright than the DT880s if I had to measure it and they make everything sound better with more texture to cymbals and stuff like that.
 
DT880s still win when it comes to the decay of instruments like hi hats cymbals crashes etc. and some acoustic tracks.
 
Alpha Dogs are incredible for closed headphones and IMO endgame for me
 
DT880s are better for gaming and positioning for some music genres
 
They are both complimentary to each other and I will probably never sell my DT880s unless I get an HD800 or T1 
 
May 8, 2014 at 8:32 AM Post #7,327 of 12,546
So each jump in dB is quite a big jump in power, which is probably why they recommend a 5W per channel amp for the HE-6's.


But as you can see, there's no really need for that. @90dB is already in the hearing loss level. People who says that thinks that more power = better which is not true at all. Power is only one technical aspect of an amplifier. Many can argue that more power will give you more headroom and that's true, but would you want more headroom in the hearing loss level? I certainly wouldn't :p
 
May 8, 2014 at 8:38 AM Post #7,328 of 12,546
Assume the amp has constant open loop gain at the two gain settings (which are probably closed loop gain settings).
This is a simple tube amp, it may have only one voltage gain stage, or maybe two or three, so it probably has low open loop gain, and hence low feedback.

Level 1:   +6 dB of gain      more feedback, hence less distortion and wider high f bandwidth

Level 2:  +12 dB of gain     less feedback, hence more distortion, and less high f bandwidth.

This could be why the two gain settings sound different.

Since I don't have schematic, I'm just guessing.

If it was an Op Amp based headphone amp and had a tremendous amount of Open Loop gain, then I would say you are more likely to be correct.  But even a practical Op Amp doesn't have infinite Open Loop Gain and Infinite bandwidth. So it won't have infinite feedback, and therefore, always has some residual distortion.

As for the tubes, if you sub one 5654 for another they should sound the same, because they are both 5654 tubes.......right?  Definitely maybe.
And if they ain't, what's the difference: gain parameters and parasitic capacitance, inductance.   Louder or softer, more bandwidth or less bandwidth.

Ok, I get your point.
But first, would these changes be audible?
And second, wouldn't you say it was bad implemented then? I mean, if these are known issues, shouldn't they be addressed when design the amp? So that the ending result would be only an increase in volume not in distortion whatsoever. Or shouldn't this rise in distortion for example be advised on the amp specs when changing gain (as they do with tubes)?

--edit don't know if I made myself clear
 
May 8, 2014 at 2:17 PM Post #7,329 of 12,546
Beyer's spec is closer to do not exceed 100 mW if you don't want to burn your headphones down.
600 Ohm DT880 kind of, sort of work OK from a wee little FiiO E17 if you set the gain at +12 dB.
Maximum output of the E17 is approx. 2 Vrms.

 
I get the feeling that at +12dB, the op amp might be pushed harder depending on the input signal (the O2 ran into this same problem), and that's not to mention we both know 2Vrms is not quite enough.
 
If it was, then the MacBook Pro should also be able to push the 600 Ohm Beyers since it can also output around 2Vrms.
 
But as you can see, there's no really need for that. @90dB is already in the hearing loss level. People who says that thinks that more power = better which is not true at all. Power is only one technical aspect of an amplifier. Many can argue that more power will give you more headroom and that's true, but would you want more headroom in the hearing loss level? I certainly wouldn't :p

 
There is something else missing in the equation here.
 
It's not as clear cut as like, say... you put in a 90dB signal and then the amplifier will just somehow "magically" amp it up to 90dB on the headphone.
 
Because that's not how an amplifier works.
 
An amplifier takes an original signal and "amplify" the signal by multiplying the signal and output the product.
 
So whatever is put in... will come out at a fixed amount higher. There is just no way around that.
 
I'm not sure if that applies to all amplifiers, but it sure does apply to the cmoy and all of its derivatives. The volume knob, in essence, just reduces the input signal so that the output will be able to reach whatever dB you hear. But it's still essentially... whatever comes in, goes out at a fixed amount higher.
 
So a 90dB input signal can go out at like, say... 60dB. Also in the process, since the volume knob "attenuates" the signal, you're essentially losing information from the input, causing dynamic range to shrink. Thanksfully, that only happens at high gain.
 
The other consideration has to be paid to how much voltage/current the amplifier can accommodate. There are two ways an output signal can be seen by the headphone: either as a current (when your headphone's impedance is low), or as a voltage (when your headphone's impedance is high). In both cases, there is a hard limit imposed on how much voltage/current an amplifier can put out. Any more than that and a component may be fried, or a fuse would be blown. Higher voltage/current leads to more wasted power, so that power needs to be dissipated as heat elsewhere.
 
That's not to mention no op amp or amplifying circuit is truly so perfect that they can amplify any signal and return the exact same thing... with every load. In the real world, these things have physical and mechanical constraints that prevent them from being able to do their job perfectly under extreme conditions. Unfortunately, the DT880 600 Ohm does fall under this extreme condition.
 
There's a bunch of things that goes into this, so... no, it's not really so clear that you can say "oh, well, it's 90dB, so that's already causing hearing loss, so it should be fine!"
 
That is... assuming you can actually get a quality 90dB signal out of the amplifier to begin with.
 
If it's too hard, just... try to imagine this:
 
You can probably throw stone to 1 foot mark. That's easy.
Can you throw a stone 100 feet? Hmm... not quite so trivial anymore.
Can you throw 100 stones at 1 foot? Hmm... also not quite so easy anymore, is it?
 
But that's how an amplifier works in a nutshell. Extreme loads force it to either throw one stone really far, or more stones really close.
 
May 8, 2014 at 2:38 PM Post #7,330 of 12,546

"Quickly as you can, snatch the pebble from my hand." The young Caine tries and fails. "When you can take the pebble from my hand, it will be time for you to leave. -Master Kan

 
May 8, 2014 at 2:42 PM Post #7,331 of 12,546
I get the feeling that at +12dB, the op amp might be pushed harder depending on the input signal (the O2 ran into this same problem), and that's not to mention we both know 2Vrms is not quite enough.

If it was, then the MacBook Pro should also be able to push the 600 Ohm Beyers since it can also output around 2Vrms.


There is something else missing in the equation here.

It's not as clear cut as like, say... you put in a 90dB signal and then the amplifier will just somehow "magically" amp it up to 90dB on the headphone.

Because that's not how an amplifier works.

An amplifier takes an original signal and "amplify" the signal by multiplying the signal and output the product.

So whatever is put in... will come out at a fixed amount higher. There is just no way around that.

I'm not sure if that applies to all amplifiers, but it sure does apply to the cmoy and all of its derivatives. The volume knob, in essence, just reduces the input signal so that the output will be able to reach whatever dB you hear. But it's still essentially... whatever comes in, goes out at a fixed amount higher.

So a 90dB input signal can go out at like, say... 60dB. Also in the process, since the volume knob "attenuates" the signal, you're essentially losing information from the input, causing dynamic range to shrink. Thanksfully, that only happens at high gain.

The other consideration has to be paid to how much voltage/current the amplifier can accommodate. There are two ways an output signal can be seen by the headphone: either as a current (when your headphone's impedance is low), or as a voltage (when your headphone's impedance is high). In both cases, there is a hard limit imposed on how much voltage/current an amplifier can put out. Any more than that and a component may be fried, or a fuse would be blown. Higher voltage/current leads to more wasted power, so that power needs to be dissipated as heat elsewhere.

That's not to mention no op amp or amplifying circuit is truly so perfect that they can amplify any signal and return the exact same thing... with every load. In the real world, these things have physical and mechanical constraints that prevent them from being able to do their job perfectly under extreme conditions. Unfortunately, the DT880 600 Ohm does fall under this extreme condition.

There's a bunch of things that goes into this, so... no, it's not really so clear that you can say "oh, well, it's 90dB, so that's already causing hearing loss, so it should be fine!"

That is... assuming you can actually get a quality 90dB signal out of the amplifier to begin with.

If it's too hard, just... try to imagine this:

You can probably throw stone to 1 foot mark. That's easy.
Can you throw a stone 100 feet? Hmm... not quite so trivial anymore.
Can you throw 100 stones at 1 foot? Hmm... also not quite so easy anymore, is it?

But that's how an amplifier works in a nutshell. Extreme loads force it to either throw one stone really far, or more stones really close.

I was saying that with that power output (watts) into the headphone would produce 90dB SPL.
 
May 8, 2014 at 2:49 PM Post #7,332 of 12,546
I was saying that with that power output (watts) into the headphone would produce 90dB SPL.

 
Yeah, but like I said... that's assuming the signal is already loud enough to begin with. You will only reach 90dB SPL if the original signal was loud enough.
 
100mW is the maximum amount of power that the amp can deliver into the headphone, but it's not a guarantee that you'll reach 100mW no matter the input signal.
 
Again, if the signal isn't loud enough, or the gain isn't high enough, you wouldn't be able to reach 90dB SPL. And that's already taking hiss, noise, loss of signal, etc... out of the equation.
 
Anyway, that's why it's good to have some headroom... if for nothing but that you get more travel with the volume pot.
 
May 8, 2014 at 2:49 PM Post #7,333 of 12,546
How would the pros 250ohm sound with a JDS labs 02 for classical music? I already own the O2 bit I'm waiting for someone to tell me if this is a good combo to pull the trigger. I have also thought about getting some Senns HD580, which would be the better headphone for classical?
 
May 8, 2014 at 2:52 PM Post #7,334 of 12,546
How would the pros 250ohm sound with a JDS labs 02 for classical music? I already own the O2 bit I'm waiting for someone to tell me if this is a good combo to pull the trigger.

 
For the 250 Ohm one, I think the O2 would make a decent piece of gear. I actually got to listen to that combo once while I still owned the DT880 600, and I thought it sounded very good.
 
Get an ODAC if you haven't, and I think you are all set.
 
If or when you feel you would like to "bend" the sound of the DT880 because you like everything else, but you don't like the treble, then start looking at something else...
 
May 8, 2014 at 2:59 PM Post #7,335 of 12,546
Yeah, but like I said... that's assuming the signal is already loud enough to begin with. You will only reach 90dB SPL if the original signal was loud enough.

100mW is the maximum amount of power that the amp can deliver into the headphone, but it's not a guarantee that you'll reach 100mW no matter the input signal.

Again, if the signal isn't loud enough, or the gain isn't high enough, you wouldn't be able to reach 90dB SPL. And that's already taking hiss, noise, loss of signal, etc... out of the equation.

Anyway, that's why it's good to have some headroom... if for nothing but that you get more travel with the volume pot.

Oh yes, sure! You're right, might be not enough to reach that level with classical music or other better recorded songs. But most modern music is already really loud and doesn't have a huge dynamic range, in this case I think that applies.
 

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