[DeadMan]

Um, because they didn't make one.

They have an e90k for desktop that uses the original e17 and e07k as a DAC but no crossfeed. About the same power output with USB.

http://m.fiio.net/en/products/8

Any alternatives? If the E12 did not make any noise when connected via USB to a PC I would use that but I am put off by that possibility.

 

[pietcux]

USB simply does not deliver so much power. The amp could not perform so well. You might want to check on the SCHIIT FULLA.

 

[x RELIC x]

Any alternatives? If the E12 did not make any noise when connected via USB to a PC I would use that but I am put off by that possibility.

Actually, I don't listen from a PC with any gear because every time that I have I get unwanted computer noise. My MacbookPro works fine but I typically listen with my DAP either plugged in to the e12 or coax to my full size headphone amp.

The Schiit Fulla that pietcux mentioned above may be what you need for a cleaner signal. I've heard good things about it but haven't used one personally.

Edit: The Wyrd is actually the USB noise cleaning device from Schiit, not Fulla. Always get them mixed up.

 

[HotIce]

My E12 is pretty silent, noise wise.
Both when connected with PC, or laptop, or iPad, or iPhone.
I use it in low gain mode though, mostly. In high gain, you can hear some very minor noise when no audio is played, but that is no source of concern for me.

 

[Allucid]

How's the E12a for full size headphones around 300-600ohm?

 

[Dobrescu George]

How's the E12a for full size headphones around 300-600ohm?

you are on e12 not e12a thread, and e12a cannot drive hd650 and anything harder to drive.
 
it struggles with hd650, resoults are that some like, some do not like the sound.

 

[Chris J]

How's the E12a for full size headphones around 300-600ohm?

The E12A is optimized for driving low impedance phones.
It may not output enough voltage to drive a high impedance 'phone, depending on the sensitivity of the high impedance 'phone.

 

[pietcux]

How's the E12a for full size headphones around 300-600ohm?

HD650 is just find with the E12a. It has only half of The output power of the standard E12, but I drive the HD650 on low gain with both amps anyways and the volume is only around 12:00 let's say 11:30 on the standard and 12:00 on the "a" version. The E12a sounds a bit more refined though due to the better opamps.

 

[StanD]

HD650 is just find with the E12a. It has only half of The output power of the standard E12, but I drive the HD650 on low gain with both amps anyways and the volume is only around 12:00 let's say 11:30 on the standard and 12:00 on the "a" version. The E12a sounds a bit more refined though due to the better opamps.

The E12 series utilizes closedloop negative feedback and has distortion levels far below a human being's ability to perceive. The FR's are also where one cannot tell a difference. The E12A's fine point is with a lower SNR of 115 dB vs. 110 dB for the E12 one might have a better experience with high efficiency IEMs. I expect that you will not agree.

 

[pietcux]

The E12 series utilizes closedloop negative feedback and has distortion levels far below a human being's ability to perceive. The FR's are also where one cannot tell a difference. The E12A's fine point is with a lower SNR of 115 dB vs. 110 dB for the E12 one might have a better experience with high efficiency IEMs. I expect that you will not agree.

Oh the difference in sound is not large. On the DIY you can exchange the opamps and buffers. Even if the differences are not large, they are audible. The E12a sounds a bit more refined to me at times. As I have both, I can tell. I only want to state that the "a" can drive the HD650 properly.

 

[Dobrescu George]

Oh the difference in sound is not large. On the DIY you can exchange the opamps and buffers. Even if the differences are not large, they are audible. The E12a sounds a bit more refined to me at times. As I have both, I can tell. I only want to state that the "a" can drive the HD650 properly.

sorry, my wrong then. i only know that hd800 need more power than even e12 normal version. with e12, hd650 were fine, with just x5 they were needing a little more, and as e12a has the same power rating, i thought that e12a might also be not enough.
 
anyways, the muses op-amps are really something different.

  The E12 series utilizes closedloop negative feedback and has distortion levels far below a human being's ability to perceive. The FR's are also where one cannot tell a difference. The E12A's fine point is with a lower SNR of 115 dB vs. 110 dB for the E12 one might have a better experience with high efficiency IEMs. I expect that you will not agree.

i would not agree. there is a little more to e12a than just snr and other facts. i really do think that the muses op-amps are special.

 

[StanD]

Oh the difference in sound is not large. On the DIY you can exchange the opamps and buffers. Even if the differences are not large, they are audible. The E12a sounds a bit more refined to me at times. As I have both, I can tell. I only want to state that the "a" can drive the HD650 properly.

Sometimes small differences can be due to expectation.
The E12A can deliver 10.3 V_p-p while the E12 can deliver 15 V_p-p.
So that's a difference of 44.2 mW vs. 93.7 mW. A difference of 3.3 dB.
That means the peak power of the E12A will deliver around 94.1 dBSPL on the HD650's. If one listens loudly or to music that is not compressed much (volume) the 12a might not satisfy them. The E12 just cuts it for me and not always. Most portables don't even come close to the 12A at 300 Ohms.
Most contemporary music is highly compressed (volume) and in that case the 12A might work out for many people that do not listen loudly (subjective).

 

[StanD]

  sorry, my wrong then. i only know that hd800 need more power than even e12 normal version. with e12, hd650 were fine, with just x5 they were needing a little more, and as e12a has the same power rating, i thought that e12a might also be not enough.
 
anyways, the muses op-amps are really something different.
i would not agree. there is a little more to e12a than just snr and other facts. i really do think that the muses op-amps are special.

This is electronics, special in what specific way?

 

[Dobrescu George]

  This is electronics, special in what specific way?

for example, muses are known for changing signatures more than most op-amps with temperature. 
 
e12a changes SQ when it is warm, and running for some time, than when it is cold.
 
Also, it costs around 70$ only to buy the op-amp itself,it is for a reason than muses are so respected as op-amps. In fact, i should try reverse thikning, had you tried e12a, and heared no difference, or you were not pleased with the sound?

 

[StanD]

  for example, muses are known for changing signatures more than most op-amps with temperature. 
 
e12a changes SQ when it is warm, and running for some time, than when it is cold.
 
Also, it costs around 70$ only to buy the op-amp itself,it is for a reason than muses are so respected as op-amps. In fact, i should try reverse thikning, had you tried e12a, and heared no difference, or you were not pleased with the sound?

Yes I tried the E12a, compared it to the 12, using an A/B switch. Noise was the notable difference. IMO, the rest is expectation bias. Can you identify the specific property that is different. In this context signature is a vague term.