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[GUIDE] Sonic Differences Between DT770-DT990 Models & More - Page 102

post #1516 of 1643
Quote:
Originally Posted by Mshenay View Post

And impedance is what keeps Frequancy response controlled and steady, if you have to much power and not enough impedance your going to have a little more mids, treble or bass in your music. So a 600 ohm can has the Impedance to resist that additional anything from the excessive power. Ofc, as you mentioned those extras anytings might only be noticeable at extreme volumes.

 

 

 

Frequency response and driver resonant behaviour can be affected by the interaction of amp output impedance and headphone impedance. The power of the amp doesn't really have anything to do with it. 

post #1517 of 1643
Quote:
Originally Posted by Armaegis View Post

 

Frequency response and driver resonant behaviour can be affected by the interaction of amp output impedance and headphone impedance. The power of the amp doesn't really have anything to do with it. 

Still though would not a higher impedance be driven better on a more powerful amp as opposed to a lower one?

 

In addition while we are on the Subject, I'm in the process of buying a Little Dot 1+ to replace my herpy derpy Millet Hybrid [This LD 1+ has some awesome after market tubes with it] now some ppl report having issues with the LD 1+ running out of steam with 250 Ohm cans, while my seller has assured me that the Amp has enough Current to drive a 250ohm can and a 32ohm can very well, where as the issue ppl are having is with Volts [and there's plenty of volts to drive a 250 ohm can to a moderatly loud level]

 

So [since I still don't fully understand it] how does Out put imedance, volt and current levels affect how well a can is driven? 

post #1518 of 1643

Some general  stuff...

 

Everything follows the basics of Ohm's law... V = IR and P = IV (or more frequently here P = V^2/R)

where V = voltage, I = current, and R = resistance (which for our slap happy calculations we'll initially assume is the same as impedance)

 

A doubling of power gives roughly +3dB of sound. A doubling of voltage is four times the power, which is +6dB. 

 

A headphone with higher impedance needs more voltage swing to get the same amount of power as one with lower impedance (the bolded formula). On the flipside, they draw much less current. In this sense, high impedance loads are easier for an amp to drive since high current draw is typically what starts causing non-linearities in the signal. The caveat then is whether the amp can swing high enough voltage to provide sufficient volume and headroom (since transients may spike quite a lot higher than nominal listening levels).

 

That said, some amps/circuits do not like running near their voltage limits as the transistors/tubes may also have irregularities when they swing voltages that are near the levels of their power supply rails. 

 

On to more complex matters is output impedance and damping factor. An amp has an output impedance Z which basically acts like a voltage divider with the headphone load. The headphone sees a fraction of the output voltage according to R/(R+Z). Generally, the lower the Z the better since the fraction will almost always be 1, but there are some cases where higher Z is useful (short circuit protection, opamp stability, etc).

 

Headphone impedances are also non-linear and vary with frequency, with models like the Senn HD series and Beyer DT series which have rather large impedance spikes at roughly 100Hz which is their resonant frequency. Becaue of this impedance spike, the voltage division actually swings in favour of the headphone and it gains a larger fraction of the voltage at those resonant frequencies, resulting in a volume bump (and most commonly heard as a mid bass bloom)

 

Damping factor is the ratio of headphone impedance to amp output impedance, expressed as R/Z. The gist of this is how well the amp can control the driver at those resonances, meaning how well can it make the driver do what it is supposed to, instead of letting it vibrate at its resonant frequency. Sonically this comes across as how "clean" the sound is, though is hard to quantify directly. The general rule of thumb is that you want a damping factor of at least 8 for good driver control. This is less an issue for orthos since they do not resonate like a dynamic headphone. 

 

 

So blah blah blah, in general a high impedance headphone is easier to drive, and if your amp has sufficient voltage swing then you have nothing to worry about. 


Edited by Armaegis - 8/11/13 at 12:06pm
post #1519 of 1643

Very nice, so then what is the advantage of the 600 ohm over the 250 ohm? I've heard the Little Dot MK IV SE pairs really well with the DT 880 600 ohm, why is that? As most people find a 600 ohm more enjoyable on the Mk IV SE than a 250 variant, 

 

Also by head room you do mean the ability to remain un distorted at higher volumes right? A buddy of mine explained it like a Pendulum, as your increase volts the pendulum swings more,  and if your lacking in head room on an amp there's a chance for an over driven sound, or the pendilum hit's a linear spot where it should be parabolic. 

 

Thanks again for answering these questions <3 this stuff is pretty interesting. 

post #1520 of 1643
Quote:
Originally Posted by Mshenay View Post


So [since I still don't fully understand it] how does Out put imedance, volt and current levels affect how well a can is driven? 

 

http://www.soundonsound.com/sos/Jan03/articles/impedanceworkshop.asp

post #1521 of 1643
Quote:
Originally Posted by Mshenay View Post

Very nice, so then what is the advantage of the 600 ohm over the 250 ohm? I've heard the Little Dot MK IV SE pairs really well with the DT 880 600 ohm, why is that? As most people find a 600 ohm more enjoyable on the Mk IV SE than a 250 variant, 

 

Also by head room you do mean the ability to remain un distorted at higher volumes right? A buddy of mine explained it like a Pendulum, as your increase volts the pendulum swings more,  and if your lacking in head room on an amp there's a chance for an over driven sound, or the pendilum hit's a linear spot where it should be parabolic. 

 

Thanks again for answering these questions <3 this stuff is pretty interesting. 

 

Why 600 over 250? I figure bragging rights has something to do with it (bigger is better, blah blah blah). And the psychology of having a "premium" model does have an effect on perceived sound. 

 

Higher damping factor would also (in theory) provide a tighter sound in the midbass area, although this would really only be noticeable if you had a rather high output impedance on your amp. There's the possibility that the drivers are also voiced differently, though I don't think anyone has specifically confirmed this one way or the other. 

 

There's also the pickle that some headphones may have been designed intentionally to interact with high output impedances (or so people may claim; I don't know if any manufacturer has specifically stated this). There's an old international standard which states amps should have an output impedance of 120ohm, but this was really meant more for transmission lines and pro audio boards. Obviously, such a high output impedance would result in frequency shifts in most headphones. Most would say this would be a bad thing, but some might enjoy the boost in the midbass which would make the music sound warmer. In such a case, the 250 ohm headphone would have a noticeable effect, and the 600 ohm barely so. 

 

Yes, headroom is the ability to not distort at higher volumes. Or more properly, to not distort at peaks which are louder than the average level. Oftentimes people will turn an amp up near the top, but this might leaves no room for the transient highs. However, this is also dependent on the input level, so don't take this as an absolute. On the flipside it's also entirely possible to clip with the amp only turned up halfway. The pendulum analogy sorta works, sorta doesn't. Clipping would be more like it hitting a wall or something. That's not really valid either, but you get the idea. 

post #1522 of 1643
Quote:
Originally Posted by Armaegis View Post

 

Why 600 over 250? I figure bragging rights has something to do with it (bigger is better, blah blah blah). And the psychology of having a "premium" model does have an effect on perceived sound. 

 

Higher damping factor would also (in theory) provide a tighter sound in the midbass area, although this would really only be noticeable if you had a rather high output impedance on your amp. There's the possibility that the drivers are also voiced differently, though I don't think anyone has specifically confirmed this one way or the other. 

 

There's also the pickle that some headphones may have been designed intentionally to interact with high output impedances (or so people may claim; I don't know if any manufacturer has specifically stated this). There's an old international standard which states amps should have an output impedance of 120ohm, but this was really meant more for transmission lines and pro audio boards. Obviously, such a high output impedance would result in frequency shifts in most headphones. Most would say this would be a bad thing, but some might enjoy the boost in the midbass which would make the music sound warmer. In such a case, the 250 ohm headphone would have a noticeable effect, and the 600 ohm barely so. 

 

Yes, headroom is the ability to not distort at higher volumes. Or more properly, to not distort at peaks which are louder than the average level. Oftentimes people will turn an amp up near the top, but this might leaves no room for the transient highs. However, this is also dependent on the input level, so don't take this as an absolute. On the flipside it's also entirely possible to clip with the amp only turned up halfway. The pendulum analogy sorta works, sorta doesn't. Clipping would be more like it hitting a wall or something. That's not really valid either, but you get the idea. 

Yea hitting a wall either on the top or sides of the arc, but indeed I do get the idea. 

 

My next question is why does the 600 ohm variant reportedly sound better on the LIttle Dot MK IV SE, than the 250 variant? In honestly the Pro version has more clamp which results in a little more bass. That being said optimally a 600 ohm Pro version would be ideal for me [as it does exist] 

post #1523 of 1643

A 600 ohm Pro would be great but they are very hard to find. The only place I've heard of anyone getting one is Jaben in Taiwan:

 

 

Though I suppose you could just get a 600 ohm Premium and replace the headband with the Pro version. It still won't look exactly like a Pro but should give you the same clamping force.

post #1524 of 1643
Quote:
Originally Posted by devhen View Post

A 600 ohm Pro would be great but they are very hard to find. The only place I've heard of anyone getting one is Jaben in Taiwan:

 

 

Though I suppose you could just get a 600 ohm Premium and replace the headband with the Pro version. It still won't look exactly like a Pro but should give you the same clamping force.

Indeed, I think I'll be happy enough with the 250 ohm pro. 

post #1525 of 1643
Quote:
Originally Posted by Mshenay View Post

Yea hitting a wall either on the top or sides of the arc, but indeed I do get the idea. 

 

My next question is why does the 600 ohm variant reportedly sound better on the LIttle Dot MK IV SE, than the 250 variant? In honestly the Pro version has more clamp which results in a little more bass. That being said optimally a 600 ohm Pro version would be ideal for me [as it does exist] 

 

Tighter driver response and flatter frequency response due to less impedance interaction. There's also the possibility that the 600ohm drivers may be better matched (as all drivers have some variances in between them). Plus as I mentioned earlier, bigger numbers make people feel better, and placebo is a powerful thing.

 

I don't know much about the LDmk4SE. I'm assuming it has some kind of output impedance interaction that may produce a pleasing sound with the 600 ohm version.

 

Quote:
Originally Posted by devhen View Post

A 600 ohm Pro would be great but they are very hard to find. The only place I've heard of anyone getting one is Jaben in Taiwan:

 

 

 

Though I suppose you could just get a 600 ohm Premium and replace the headband with the Pro version. It still won't look exactly like a Pro but should give you the same clamping force.

 

Or get a pro model and replace the drivers. Heck, you could probably replace them with tesla drivers cool.gif

post #1526 of 1643
Quote:
Originally Posted by Armaegis View Post

 

Tighter driver response and flatter frequency response due to less impedance interaction. There's also the possibility that the 600ohm drivers may be better matched (as all drivers have some variances in between them). Plus as I mentioned earlier, bigger numbers make people feel better, and placebo is a powerful thing.

 

I don't know much about the LDmk4SE. I'm assuming it has some kind of output impedance interaction that may produce a pleasing sound with the 600 ohm version.

 

 

Or get a pro model and replace the drivers. Heck, you could probably replace them with tesla drivers cool.gif

Well bigger numbers aren't always better, the 880 sounds better than the  990 imo, 

 

Not to mention, I've come to terms with the pro 250 being better due to it's versilitility at least better for me. 

 

But again I'd love to own both versions! I just enjoy the can so much 

post #1527 of 1643

I've yet to find a Beyer that I actually like, but the DT880 is probably the one I'd choose if I had to. I haven't heard any of the Tesla range stuff yet though.

post #1528 of 1643
Quote:
Originally Posted by Armaegis View Post

I've yet to find a Beyer that I actually like, but the DT880 is probably the one I'd choose if I had to. I haven't heard any of the Tesla range stuff yet though.

:O, I'm so sorry to hear that. Well I for one enjoy the byer open cans along with Audio Technica. I just wish AT would have a better alternative to the wing system. That way I could use something like the AD900X portably. But I fear that the fit will make it overly cumbersome. The Byers how ever just slap on and stay in place, I can whip my head around or even jump up and walk around without them moving... still I might end up getting over that issue with AT cans...

 

So what do you like 

post #1529 of 1643

I actually really liked the comfort of the Audio Technica wings once I got used to them, though they're still a bit loose. An elastic pulling the wings together helps that quite a bit actually.

 

I gotta hand it to Beyer for rock solid build quality though. They got a good design and pretty much recycle it for every single can they make. Unfortunately, the same cup shape in all of them seems to promote the same treble presence that bothers me across their entire model range.

 

In terms of sound, I generally do not like Grados, Ultrasones, or Beyers. I generally do like open Sennheisers and AKGs.The headphones I've had the longest are the little Senn PX100-ii, AKG K240 Sextett, and HE-6 (modded). For closed, I have a modded Pioneer HDJ-200 and a bunch of T50rp mods or transplants.

post #1530 of 1643
Quote:
Originally Posted by Armaegis View Post

I actually really liked the comfort of the Audio Technica wings once I got used to them, though they're still a bit loose. An elastic pulling the wings together helps that quite a bit actually.

 

I gotta hand it to Beyer for rock solid build quality though. They got a good design and pretty much recycle it for every single can they make. Unfortunately, the same cup shape in all of them seems to promote the same treble presence that bothers me across their entire model range.

 

In terms of sound, I generally do not like Grados, Ultrasones, or Beyers. I generally do like open Sennheisers and AKGs.The headphones I've had the longest are the little Senn PX100-ii, AKG K240 Sextett, and HE-6 (modded). For closed, I have a modded Pioneer HDJ-200 and a bunch of T50rp mods or transplants.

Nice, I agree on the Wing system... once you figure it out it is very nice. The w1000x is heavy as crud imo [it's got wood cups so you  know] that being said the wing system really does make it almost float on my head :O

 

And sadly I rather like the Treble of byer cans xD 

 

That being said, have you heard about the Alpha Dog? I'm curious to how much improvement it's made over the Mad Dog, for twice the asking price I'd hope it's some what obvious 

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