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post #466 of 768

The T50RP only needs 10mW to get to 105dB and 320mW to get to 120dB. The Magni can put out ~1W at the T50RP impedance. That said, the Magni is practically the definition of overhead power for the T50RP. Spending more will achieve different amp architecture and signatures but the whole power issue is hardly an issue at all for these headphones.

post #467 of 768
Quote:
Originally Posted by Thujone View Post
 

The T50RP only needs 10mW to get to 105dB and 320mW to get to 120dB. The Magni can put out ~1W at the T50RP impedance. That said, the Magni is practically the definition of overhead power for the T50RP. Spending more will achieve different amp architecture and signatures but the whole power issue is hardly an issue at all for these headphones.


You're right, volume isn't really the issue, as even an iphone gets t50rp's loud enough, it's more getting the most from the headphones "timbre" and "dynamic range."  The cleaner and more power you can get into that 3000mW max handling of the t50rp the better the driver will sound.  There's a couple amps out there that will distort the bass while they do get enough volume, the JDS C5/421 for example quickly distorts the lower bass when pushed loud at all.

 

I've heard great things about the Magni and Vali!  Will probably pull the trigger on one of them at some point.


Edited by zach915m - 2/19/14 at 8:29am
post #468 of 768
Quote:
Originally Posted by zach915m View Post
 


You're right, volume isn't really the issue, as even an iphone gets t50rp's loud enough, it's more getting the most from the headphones "timbre" and "dynamic range."  The cleaner and more power you can get into that 3000mW max handling of the t50rp the better the driver will sound.  There's a couple amps out there that will distort the bass while they do get enough volume, the JDS C5/421 for example quickly distorts the lower bass when pushed loud at all.

 

I've heard great things about the Magni and Vali!  Will probably pull the trigger on one of them at some point.

 

I wouldn't say more power is pointless, but it isn't necessary. I agree though, some amps can handle them and some can't. The Bottlehead Crack is a good example. You'll be able to get enough volume (enough power) but they sound terrible. My question is this: is this pairing terrible due to the Crack's architecture geared towards high impedance headphones or is it truly a matter of power?

 

This is something that I don't have enough experience to answer. To me, as stated in my last post, you need X watts to get to Y volume. An amp like the Lyr can put ~4W into these puppies but it doesn't change the fact that the Lyr, Magni, or w/e will only be putting out 10mW to get to 105dB. Putting all 3000mw (3W) into the T50 will make them extremely loud, so what is the use of all this overhead power? I'm asking because I honestly don't know. When I've asked this in the past, I get answers along the lines of "because it's nice to have overhead"...

post #469 of 768

I think a lot of amp recommendations are based on experience.

My solid state is perfectly able to drive my 600 ohm DT 880 CB.

Paired with the ZMF. I get volume enough, but the sound is downright lame.

The tube hybrid make the ZMF swing and sing with impact and a tuneful bass.

 

On the other hand, the tube hybrid doesn't sound good with the 600 ohm Beyer. The only other headphone besides the ZMF that goes along with that amp is the GMP 250 (100 ohm, low sensitivity).

My other cans sounds 'better' with the solid state.

Therefore I need two amps.

 

It doesn't make any sense to me, but that's what I hear....

post #470 of 768
Quote:
Originally Posted by Tiemen View Post
 

I think a lot of amp recommendations are based on experience.

My solid state is perfectly able to drive my 600 ohm DT 880 CB.

Paired with the ZMF. I get volume enough, but the sound is downright lame.

The tube hybrid make the ZMF swing and sing with impact and a tuneful bass.

 

On the other hand, the tube hybrid doesn't sound good with the 600 ohm Beyer. The only other headphone besides the ZMF that goes along with that amp is the GMP 250 (100 ohm, low sensitivity).

My other cans sounds 'better' with the solid state.

Therefore I need two amps.

 

It doesn't make any sense to me, but that's what I hear....

 

Yup, I think you and I are experiencing the same thing. As far as I can tell, an amp's pairing ability with a specific headphone has nothing to do with power output (so long as you have enough power to get to listening levels). Another good example are the HE-6 users who are using Project Ember while many others are using high powered speaker amps.

post #471 of 768

As I understand it, there's also a difference in what a headphone needs.

Those with a high impedance will benefit from an amp that delivers lots of voltage, like OTL tube amps.

Headphones with lower impedance have more need for current, delivered by solid state and tube hybrids.

This as a general rule.

When I had a OTL tube amp, the only headphone that sounded too my likings with them were the AKG K240 Sextett.

Not for example the DT880 250 ohm or the DT150, also 250 ohm.

 

The sensitivity of the headphone seems to plays a role as well.

 

I tried to understand this writing http://www.soundonsound.com/sos/Jan03/articles/impedanceworkshop.asp ,

but it's a bit too complicated for me.

post #472 of 768

Thanks for the link, I'll check it out. Yeah, voltage and current required will vary based on impedance. That said, power supplies are really important as well.

post #473 of 768

Schiit told me to go with the Vali (instead of the Magni) with the ZMF :-) So I'll be picking up the Modi with the Vali. Still awaiting eagerly for my ZMF of course :D 

post #474 of 768


From what I understand, ortho's need more Voltage to reach the same volume than a dynamic headphone even if they have the same sensitivity. 

 

There's a good thread on why Ortho's need more power here:  http://www.head-fi.org/t/606260/orthodynamic-headphones-voltage-and-watts

post #475 of 768
Quote:
Originally Posted by zach915m View Post
 


From what I understand, ortho's need more Voltage to reach the same volume than a dynamic headphone even if they have the same sensitivity.

 

There's a good thread on why Ortho's need more power here:  http://www.head-fi.org/t/606260/orthodynamic-headphones-voltage-and-watts

 

Right on, good thread. Again, this seems to confirm my hypothesis that "more power is better" is incorrect. Like he states in the 4th post, the headphones don't "know" how much power the amp can output, all it knows is how much it's receiving (i.e. 10mW at 105dB). Yes, the T50 driver will need more power to reach 105dB than your typical dynamic headphone with similar impedance but the efficiency/sensitivity numbers are what determines that 10mW requirement. AKA take two completely different headphones with equal efficiency values and they will require the same amount of power (X) for a given volume (Y). The main point of that thread is that orthos typically have very low sensitivities despite their impedance.

post #476 of 768
Quote:
Originally Posted by Thujone View Post
 

 

Right on, good thread. Again, this seems to confirm my hypothesis that "more power is better" is incorrect. Like he states in the 4th post, the headphones don't "know" how much power the amp can output, all it knows is how much it's receiving (i.e. 10mW at 105dB). Yes, the T50 driver will need more power to reach 105dB than your typical dynamic headphone with similar impedance but the efficiency/sensitivity numbers are what determines that 10mW requirement. AKA take two completely different headphones with equal efficiency values and they will require the same amount of power (X) for a given volume (Y). The main point of that thread is that orthos typically have very low sensitivities despite their impedance.

 

The reason headroom is nice to have in general, is because you have less chance of distorting at any volume.  It's like if you're driving 75 on the the highway in a v4 Hyundai vs 75 in a V8 Porsch.  They are both going the same speed, but on one the engine is trying very hard, and the other the engine is purring.  You may be able to get the desired volume out of an amp with 400 mW as an amp with 4000mW, but the amp with 4000 mW doesn't have to try as hard to get you there, so there is less chance of distortion, and the power will be cleaner.  Ofcourse there are a huge amount of variables, and as you well know, an amp with great internals and a lower output can sound just as good as one with much higher output. 

 

So with Ortho's because of the low sensitivities despite their impedance, in this case of 50 ohm's, it's just a safer bet to go for more power unless you've either heard the amp in question, or you have a trusted source tell you it works well with the headphone in question!  Which is why head-fi is so great!

post #477 of 768

So these headphones do indeed like a bit of excess. Especially for louder sessions.

 

sorry. What I'm saying is I want to make sure i drive them not just good enough but the slight overkill factor is what im looking for and to have potential for possibly even more demanding sets in the future.


Edited by rock&rollfrenchfries - 2/19/14 at 1:26pm
post #478 of 768
Quote:
Originally Posted by zach915m View Post
 

 

The reason headroom is nice to have in general, is because you have less chance of distorting at any volume.  It's like if you're driving 75 on the the highway in a v4 Hyundai vs 75 in a V8 Porsch.  They are both going the same speed, but on one the engine is trying very hard, and the other the engine is purring.  You may be able to get the desired volume out of an amp with 400 mW as an amp with 4000mW, but the amp with 4000 mW doesn't have to try as hard to get you there, so there is less chance of distortion, and the power will be cleaner.  Ofcourse there are a huge amount of variables, and as you well know, an amp with great internals and a lower output can sound just as good as one with much higher output.

 

So with Ortho's because of the low sensitivities despite their impedance, in this case of 50 ohm's, it's just a safer bet to go for more power unless you've either heard the amp in question, or you have a trusted source tell you it works well with the headphone in question!  Which is why head-fi is so great!

 

I completely agree with what's written here. You wouldn't want to buy a 10mW max output power amp for your 105dB listening unless your amp works perfectly fine under 100% load and has a great power supply to help it out (unlikely). Now I understand where you are coming from when you say "more = better" because "more = safety blanket". Still though, it's not necessarily "better", just safe.

 

My issue is with the idea of "more = better" in that a Lyr (which already has 99.75% overhead power at 105dB since you are using 10mW out of the available 4000mW at this impedance) is completely inferior to a 20W per channel speaker amp just because the speaker amp has a higher number before the "W". I can tell you from personal experience that when you are using a speaker amp like that, you have to listen with the potentiometer so low that you are in the zone for pot inconsistencies. I had the Emotiva mini which had terrible imbalance issues due to the pot at low gain. This is literally the opposite problem as what you stated above. A low geared V8 would much rather be going 60mph than 10mph :D.

 

Anyway, thanks for the discussion, Zach!

post #479 of 768
Quote:
Originally Posted by rock&rollfrenchfries View Post
 

So these headphones do indeed like a bit of excess. Especially for louder sessions.

 

sorry. What I'm saying is I want to make sure i drive them not just good enough but the slight overkill factor is what im looking for and to have potential for possibly even more demanding sets in the future.

 

Go for Project Ember then. :)

post #480 of 768

Yes i want something that glows and looks fancy. 

 

Oh but that really is quite a purchase. what about one of their lesser series's. Is there really no improvement over $120 magni and lyr and 02 until i get all the way to $350?


Edited by rock&rollfrenchfries - 2/19/14 at 2:35pm
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