Head-Fi.org › Forums › Summit-Fi (High-End Audio) › High-end Audio Forum › Speaker amps for headphones
New Posts  All Forums:Forum Nav:

Speaker amps for headphones - Page 13

post #181 of 2668
Quote:
Originally Posted by Chris J View Post


Try figuring out how much power the headphones take for an SPL of 90 dB.
Yamaha should have a sensitivity figure ( how much voltage they require for s specific SPl) or an efficiency figure (how much power they require for a specific SPL) published somewhere.

3 Watts is more like what it takes to burn the headphones down.

Edit:
I just looked these phones up on the 'net, 94 dB @ 1 mW.
So 1 mW will actually be fairly loud!

the average headphone really doesn't need much power......redface.gif

Actually, I think its the 10 W Maximum burns-'em-down...

 

Asgard II on high gain (somewhere around 750 mW into 150 ohms) is loud, but runs out of steam in a lot of passages.  Especially base heavy, complex stuff.  

One question I have is how is that 94 dB @ 1mW measured?  Is that a 1 kHz test signal?  Maybe the bass response is much less than 94 dB @ 1 mW?

post #182 of 2668
No offense or condescension intended at you, I assure you. I also learned a lot from this thread and, in particular, from Operakid who was the OP. I, like you, have no interest in frying any of my 'phones, just getting them to sound their best. With the 5LE, I can drive it even without the resistors I have pictured in an earlier post here. The key to this process is to always be as careful as one would be with any electronics.
Best of luck in your search.
post #183 of 2668
Oh, no worries man! I didn't take it that way to all, just throwing out a plug for other hapless noobs like myself wink.gif

I've got an old Trends amp (based on a Tripath chip, I believe) that I've been eyeing to press into service as a headphone amp... Gonna keep reading until I'm reasonably sure I won't end up blowing up the planet in a fiery inferno in the process :P
post #184 of 2668
Quote:
Originally Posted by Theogenes View Post

Oh, no worries man! I didn't take it that way to all, just throwing out a plug for other hapless noobs like myself wink.gif

I've got an old Trends amp (based on a Tripath chip, I believe) that I've been eyeing to press into service as a headphone amp... Gonna keep reading until I'm reasonably sure I won't end up blowing up the planet in a fiery inferno in the process :P

 

Watch those tripaths. A lot of the chips they were based on are internally bridged and do not take kindly to having the output grounds connected (like in a 3 conductor headphone plug).

post #185 of 2668
Quote:
Originally Posted by potterma View Post

Actually, I think its the 10 W Maximum burns-'em-down...

 

Asgard II on high gain (somewhere around 750 mW into 150 ohms) is loud, but runs out of steam in a lot of passages.  Especially base heavy, complex stuff.  

One question I have is how is that 94 dB @ 1mW measured?  Is that a 1 kHz test signal?  Maybe the bass response is much less than 94 dB @ 1 mW?

 

Ooops, you're right, 10 Watts seems to be the burn limit.

Very hard to believe that a dynamic headphone voice coil can take 10 Watts or even 1 Watt.............confused_face_2.gif

 

Try listening to some music, and if possible, measure the average voltage into the 'phones.

You'll probably get some average level close to 1-10 mW, i.e. way below 750 Watts.

94 dB @ 1 mW probably is a 1 kHz test tone.  As an approximation, you would still need approx. 1 mW @ 94 dB @ 100 Hz.

 

I've tried measuring average voltage into my loudspeakers and found that an average level of 1 or 2 Watts was about as loud as I wanted to listen! So you could argue that the peaks may be approx. 10 or 20 or 40 Watts. I've never seen the clipping indicators light up in a 80 Watt and 120 Watt power amp I have (when using them to drive loudspeakers).

But I have heard my subwoofer clip at high volumes!

post #186 of 2668
Quote:
Originally Posted by Theogenes View Post

 

I'm sure the guiding principles behind it are relatively simple, particularly for those who have a background that at least tangentially involves dealing with electronics. Some of us (myself most definitely included) come from a perspective of absolutely loving music, which drew us into the gear that reproduces it, but never had any real dealings with what was inside all those metal boxes. If I did something that would be obviously foolish to someone with a greater knowledge level than I and ended up torching my LCD-2, for example, I would be whatever is exponentially worse than 'upset.' 

 

Fortunately though, I know I'm not the only one who reads threads like this in an attempt to learn a little about the dark arts of wires and resistors and whatnots. wink.gif

LCD-2 are so inefficient that they are exactly the kind of headphone that you may want to drive directly from the output of a power amp.

Take a look at the Decware Taboo thread.

That's what all those guys are doing with their LCD-2 and Taboos.

 

As I mentioned a few posts earlier, I've tried driving a pair of 2,000 Sennheisers directly off the output of a 150 Watt amp, the 'phones have never sounded better and I had no problem controlling the volume. But I would never leave the headphones plugged into the amp without turning the volume down to almost zero first. But then, don't we all do this when changing from one source to another in our stereos?

I'm just sayin, you don't necessarily need a resistor network. For all you would be experiementers out there, don't be afraid to try it either way.

post #187 of 2668
^ That's right Chris, albeit Mr Deckert (Taboo's designer) conveniently provided us an hp output once Frank I suggested the idea to him wink.gif It is a direct connection I believe, meaning we're getting a good 1.7 or more W into our LCDs (the Taboo II I own is rated 6W into 8 ohms).

As you know, we're a mad bunch in the Decware Taboo thread biggrin.gif
post #188 of 2668
Quote:
Originally Posted by Chris J View Post

 

Ooops, you're right, 10 Watts seems to be the burn limit.

Very hard to believe that a dynamic headphone voice coil can take 10 Watts or even 1 Watt.............confused_face_2.gif

 

... snip ...

Actually, the HP-1 is a planar magnetic driver, not dynamic.

post #189 of 2668
Quote:
Originally Posted by potterma View Post

Actually, the HP-1 is a planar magnetic driver, not dynamic.

Ooooops again,
Then it has massive efficiency for a planar magnetic..........or a suspiciously high efficiency......makes me wonder how accurate that number is?
post #190 of 2668
Quote:
Originally Posted by AiDee View Post

^ That's right Chris, albeit Mr Deckert (Taboo's designer) conveniently provided us an hp output once Frank I suggested the idea to him wink.gif It is a direct connection I believe, meaning we're getting a good 1.7 or more W into our LCDs (the Taboo II I own is rated 6W into 8 ohms).

As you know, we're a mad bunch in the Decware Taboo thread biggrin.gif

Hey man,
looks like they changed to using a 150 Ohm series resistor in the Taboo III when they added the super, ultra, custom special Lucid Mode.....tongue.gif

I guess the Taboo IIi just adds more resistors! New power rating into the LSD-2 is 1.7 Watts. How are you going to listen to Black Sabbath with only 1.7 Watts?
Edited by Chris J - 5/26/13 at 5:18am
post #191 of 2668
Quote:
Originally Posted by Chris J View Post


Ooooops again,
Then it has massive efficiency for a planar magnetic..........or a suspiciously high efficiency......makes me wonder how accurate that number is?

Yes, me too.  Perhaps they slipped a decade.... 

post #192 of 2668
Quote:
Originally Posted by Hutnicks View Post

Watch those tripaths. A lot of the chips they were based on are internally bridged and do not take kindly to having the output grounds connected (like in a 3 conductor headphone plug).

 

Quote:
Originally Posted by Chris J View Post

LCD-2 are so inefficient that they are exactly the kind of headphone that you may want to drive directly from the output of a power amp.

Take a look at the Decware Taboo thread.

That's what all those guys are doing with their LCD-2 and Taboos.

 

As I mentioned a few posts earlier, I've tried driving a pair of 2,000 Sennheisers directly off the output of a 150 Watt amp, the 'phones have never sounded better and I had no problem controlling the volume. But I would never leave the headphones plugged into the amp without turning the volume down to almost zero first. But then, don't we all do this when changing from one source to another in our stereos?

I'm just sayin, you don't necessarily need a resistor network. For all you would be experiementers out there, don't be afraid to try it either way.

 

Good info. Thanks to you both!!

post #193 of 2668
^ LOL - bah, who cares? As Hamlet said after struggling futilely with his series and parallel resistors - these were hard to come by in Shakespeare's day - "I am ill at these numbers" biggrin.gif

(Things then got worse. After hearing Black Sabbath with one particularly bad combination, his girlfriend threw herself in the river and drowned eek.gif)

But what's this you say? Steve added 150 ohms? Gadzooks!

Or to be serious a moment, won't that warm the sound, quite a lot???

Quote:
Originally Posted by Chris J View Post

Hey man,
looks like they changed to using a 150 Ohm series resistor in the Taboo III when they added the super, ultra, custom special Lucid Mode.....tongue.gif

I guess the Taboo IIi just adds more resistors! New power rating into the LSD-2 is 1.7 Watts. How are you going to listen to Black Sabbath with only 1.7 Watts?
post #194 of 2668
Quote:
Originally Posted by AiDee View Post

^ LOL - bah, who cares? As Hamlet said after struggling futilely with his series and parallel resistors - these were hard to come by in Shakespeare's day - "I am ill at these numbers" biggrin.gif

(Things then got worse. After hearing Black Sabbath with one particularly bad combination, his girlfriend threw herself in the river and drowned eek.gif)

But what's this you say? Steve added 150 ohms? Gadzooks!

Or to be serious a moment, won't that warm the sound, quite a lot???

 

Oh no!

The output impedance question will start World War Z! (Which was written by Shakespeare, BTW. Or was it Jane Austin?)  blink.gif

 

Judging by all the guys on the Vintage Receiver thread who swear by vintage recievers to drive their headphones, the high output impedance in these receivers does no harm.

 

OTOH, I have a vintage CR-2020 Yamaha Receiver, let's just say it is not my favourite headphone amp. Nice and warm and mellow maybe, but that's about it. It ain't the last word in transparency................wink_face.gif

post #195 of 2668
I got to briefly listen to an old Sansui amp driving a pair of HE-6 from the headset jack at the Canlanta meet, and the sound was surprisingly impressive... If the thing wasn't so huge, it would be worth buying one just to drive orthos IMO.
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: High-end Audio Forum
Head-Fi.org › Forums › Summit-Fi (High-End Audio) › High-end Audio Forum › Speaker amps for headphones