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 103

post #1531 of 2754
Quote:
Originally Posted by Steve Eddy View Post
 

 

... snip ...

 

@potterma, do you happen to know what the input sensitivity of the MG3 is?

 

se

 

I don't, sorry.  Did a quick search on the page but didn't find it.  The gain is high, but I don't know how high.

post #1532 of 2754
Quote:
Originally Posted by potterma View Post
 

 

I don't, sorry.  Did a quick search on the page but didn't find it.  The gain is high, but I don't know how high.

 

Thanks. Yeah, I suspect has quite a bit of excess gain (considering sources in the 1.5 to 2 volt range are common these days) and that could explain audible hiss with headphones like the LCD-2s.

 

se

post #1533 of 2754
Quote:
Originally Posted by Steve Eddy View Post
 

 

Thanks. Yeah, I suspect has quite a bit of excess gain (considering sources in the 1.5 to 2 volt range are common these days) and that could explain audible hiss with headphones like the LCD-2s.

 

se

Question for you se. Why do so many designers go overkill on the gain? Is it just to give the amp a broader market or is there more behind it?

post #1534 of 2754
Quote:
Originally Posted by brunk View Post
 

Oh, you can with as little as a gain of 2. The designer of the amp is doing this very thing with HE-6. Only need to switch out 2 resistors :D 

 

Amp is no joke lol!

Really?  What source is he using?  Must be like a X-Sabre or something similar with a high output voltage?

 

What's the current output on that thing?


Edited by potterma - 11/28/13 at 7:34pm
post #1535 of 2754
Quote:
Originally Posted by potterma View Post
 

Really?  What source is he using?  Must be like a X-Sabre or something similar with a high output voltage?

Yeah he's using a ESS9018, DIY of course.

 

EDIT: It's not an optimal pairing though for the HE-6. It's just a little short on current (~250) for it.


Edited by brunk - 11/28/13 at 7:41pm
post #1536 of 2754
Quote:
Originally Posted by brunk View Post
 

Yeah he's using a ESS9018, DIY of course.

Of course!  

post #1537 of 2754
Quote:
Originally Posted by brunk View Post
 

Question for you se. Why do so many designers go overkill on the gain? Is it just to give the amp a broader market or is there more behind it?

 

Couldn't tell you I'm afraid. Habit perhaps? Some years ago I went through the Stereophile buyer's guide and the typical input sensitivity of power amps was around 500mV. Pretty weird given that preamps typically had about 20dB of gain.

 

se

post #1538 of 2754
Quote:
Originally Posted by Steve Eddy View Post
 

 

Couldn't tell you I'm afraid. Habit perhaps? Some years ago I went through the Stereophile buyer's guide and the typical input sensitivity of power amps was around 500mV. Pretty weird given that preamps typically had about 20dB of gain.

 

se

Yeah, it's a habit that needs to die lol :tongue: but I think people would start calling an amp "underpowered" if they went past 1 o'clock on the dial lol. Maybe that's why...:rolleyes:

post #1539 of 2754
Quote:
Originally Posted by brunk View Post

Yeah, it's a habit that needs to die lol tongue.gif  but I think people would start calling an amp "underpowered" if they went past 1 o'clock on the dial lol. Maybe that's why...rolleyes.gif

Well I know when I was a teenager I was more impressed with stereos that cranked before 12 O'clock. biggrin.gif

se
post #1540 of 2754
Quote:
Originally Posted by Steve Eddy View Post


Well I know when I was a teenager I was more impressed with stereos that cranked before 12 O'clock. biggrin.gif

se

Ha! So true :biggrin:

post #1541 of 2754

Strange, when Gary tested the Millenia with LCD3 the results were great. Resistance is almost the same (45 vs 50) and using the same TBI box he could not use the volume above 9 o'clock. Even if it's under powered that it still a lot of headroom. Maybe the Millenia is not a good match with LCD2, event if this little amp is great you cannot expect to be a perfect match will all headphones. 

Thinking of snatching one for my LCD3 and I will build my own resitor box with R2= 3 or 4 and R1 = 10.

post #1542 of 2754

The spec that Jan Plummer keeps mentioning is 91 dB at 1mW for the LCDs.  The Audeze cans have low impedence but they are relatively efficient so you don't need huge power to drive them.  I have never felt that the Millenia strained at all to drive the LCD-3s.

post #1543 of 2754
Quote:
Originally Posted by Steve Eddy View Post
 

 

Personally I think 1 watt's fine with the LCD-2's, but if you don't want to go lower than that, using a 50 ohm series resistor is as much as you can get away with and will only reduce the noise by 3dB SPL.

 

Just how significant is the noise?

 

se

 

Thanks Steve.  I'll try a 50 ohm series resistor first.  :smile:

 

The noise heard by most of us who have tried using various headphones directly connected to the MG3 could be described as something like tape hiss - as in what you would hear without Dolby NR when playing a cassette tape. 

 

Quote:
Originally Posted by m17xr2b View Post
 

Strange, when Gary tested the Millenia with LCD3 the results were great. Resistance is almost the same (45 vs 50) and using the same TBI box he could not use the volume above 9 o'clock. Even if it's under powered that it still a lot of headroom. Maybe the Millenia is not a good match with LCD2, event if this little amp is great you cannot expect to be a perfect match will all headphones. 

Thinking of snatching one for my LCD3 and I will build my own resitor box with R2= 3 or 4 and R1 = 10.

 

I was perfectly happy with my LCD-2 on the MG3 using Jan Plummer's resistor network to get rid of the hiss, even after learning that the 50-Ohm LCD-2 were only getting 124mW per channel, but yesterday, I connected my HD600 to the same MG3 + resistor box and realized how power-starved the LCD-2 sounds, in terms of dynamics.  Seriously, the LCD-2 sounds great on the MG3 + resistor box - for a lot of reasons beyond slam or dynamics, but the HD600 sounds better still, overall - particularly in terms of dynamics - no doubt because it's a lot happier than the LCD-2 is, running on so little power.

 

Gary can chime in, of course, but keep in mind that he quickly moved past using the MG3 + resistor box to drive his LCD-3, ending up with an Odyssey Cyclops Extreme - directly connected - with none of the hiss he had experienced with the MG3 sans resistor box, and now his LCD-3 is enjoying 110W into 8 Ohms (with no resistors, that works out to something like 14.67 Watts into his 60 Ohm LCD-3).

 

Let me add that there are several respected Head-Fi members who have touted the LCD-2 and LCD-3 for how well they scale when connected to amps that approach their maximum permissible rating of 13 Watts rms into 50 Ohms.  The higher you go above 1W, the better they sound.  Anything less than 1W is subjectively "unacceptable."

 

Mike


Edited by zilch0md - 11/28/13 at 10:41pm
post #1544 of 2754

So 128mw into 91db sensitivity = 115db for audeze. I think that is enough for most people. I think most people do not understand how power affects sound level. Each doubling of power increases the sound pressure by 3db. I could not believe at first that going from 1mW to 2mW is the same as from 10W to 20W.


Edited by m17xr2b - 11/28/13 at 10:48pm
post #1545 of 2754

I don't remember if it was answered before, but can the MG3 be ordered with a lower gain?

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