[Brain Damage]

Not normal at all. It should be smooth and quiet.

Agree with @rcostas4 , this is not normal. Certainly not my experience - should be very smooth and silent when turning up and down.

 

[hawkhead]

Ok - thanks for the replies - will get in touch with Hifiman

 

[jcmttmyr]

Wow. Just as I began to forget about my Hifiman EF400 – being sucked into the tube rolling game with the Schiit Lyr 3 – the Focal Utopias came into my life, but I really did not like them with the latter (I do prefer the Lyr 3 with my Hifiman HE1000se, nonetheless). Hence, I gave the EF400 another spin again, and what can I say… it does work some magic with the Utopias, providing great punch and smoothness, but most importantly, more clarity than the Schiit stack (in addition to the Lyr 3, there's the Bifrost 2/64 working here). I wasn't really expecting this, but to me, it's a great pairing. The only downside is the sheer amount of power the EF400 provides, rendering the usable range of the volume knob with the very efficient Utopias very slim. It's fiddly.

I already had ordered a Ferrum stack (the OOR with the HYPSOS) which I'm awaiting to arrive next week, and I'm curious what's there to improve, if anything. For the meantime, the OOR will also be fed by the Bifrost 2/64. Did someone have the chance to compare the OOR to the EF400 recently, possibly even with the Utopias? I'd be interested in your observations!

Nevertheless, I fell in love again with this little beast.

 

[Hyde00]

Focal Utopias came into my life, but I really did not like them with the latter (I do prefer the Lyr 3 with my Hifiman HE1000se, nonetheless). Hence, I gave the EF400 another spin again, and what can I say… it does work some magic with the Utopias, providing great punch and smoothness, but most importantly, more clarity than the Schiit stack (in addition to the Lyr 3, there's the Bifrost 2/64 working here). I wasn't really expecting this, but to me, it's a great pairing.

Just out of curiosity, have you tried using EF400 as a dac and feed into the Lyr 3 just to see what happens lol.

I'm curious the pairing is not well is it because the amp portion (EF400 amp vs Lyr 3) or dac portion (EF400 dac vs Bifrost 2).

 

[jcmttmyr]

Just out of curiosity, have you tried using EF400 as a dac and feed into the Lyr 3 just to see what happens lol.

I'm curious the pairing is not well is it because the amp portion (EF400 amp vs Lyr 3) or dac portion (EF400 dac vs Bifrost 2).

Good point! Yes, I fed the Lyr 3 also with the EF 400, and the overall impression remained. So it seems to be more the amp portion that doesn't click with my chain – albeit I I'm impressed how good the Lyr 3 sounds with the DAC of the EF400. I will really have to evaluate whether the Bifrost 2/64 or the EF400 pairs better with the OOR then, oddly enough.

 

[ozz007]

Good point! Yes, I fed the Lyr 3 also with the EF 400, and the overall impression remained. So it seems to be more the amp portion that doesn't click with my chain – albeit I I'm impressed how good the Lyr 3 sounds with the DAC of the EF400. I will really have to evaluate whether the Bifrost 2/64 or the EF400 pairs better with the OOR then, oddly enough.

I 100% understand the r2r dac is really good.

 

[Hyde00]

Good point! Yes, I fed the Lyr 3 also with the EF 400, and the overall impression remained. So it seems to be more the amp portion that doesn't click with my chain – albeit I I'm impressed how good the Lyr 3 sounds with the DAC of the EF400. I will really have to evaluate whether the Bifrost 2/64 or the EF400 pairs better with the OOR then, oddly enough.

I 100% understand the r2r dac is really good.

lol yeah from what I read the R2R on EF400 is actually quite good, and the amp is suppose to be pretty linear similar to THX AAA.

I think someone hook up the EF400 dac to a THX AAA amp and couldn't tell a difference vs the EF400 internal amp.

So maybe you like the more linear approach on the amp.

 

[shadow1121]

Recently, I encountered an unfortunate power surge at my location, which subsequently affected my EF400.

At first, the device was unable to power on. However, after a few days, it did power on successfully but failed to respond to input from either of the input plugs.

With the assistance of a friend, I opened the board and discovered that the surge had damaged several inductors, diodes, and capacitors on the DAC and USB side. I aim to repair it by replacing these damaged components, but I am unable to ascertain the specific details or specifications of the affected parts.

Seeking assistance, I am posting here in the hopes that @TeamHiFiMAN might be able to provide the necessary details to facilitate the repair.

​

 

[TeamHiFiMAN]

Recently, I encountered an unfortunate power surge at my location, which subsequently affected my EF400.

At first, the device was unable to power on. However, after a few days, it did power on successfully but failed to respond to input from either of the input plugs.

With the assistance of a friend, I opened the board and discovered that the surge had damaged several inductors, diodes, and capacitors on the DAC and USB side. I aim to repair it by replacing these damaged components, but I am unable to ascertain the specific details or specifications of the affected parts.

Seeking assistance, I am posting here in the hopes that @TeamHiFiMAN might be able to provide the necessary details to facilitate the repair.

​

Hi there, sorry to hear that. Can you please email us at customerservice@hifiman.com, and describe your questions in the email so our support team can try to help. Maybe we can provide a paid replacement if the issue cannot be fixed.

 

[mjobolks]

Does the gain and os and nos effected the line out or is it completely static? For 300 and some hefty change this is a very competitively priced R2R dac without even considering the amp.

 

[Gymboy]

Lowered price cost is because interchannel phase issues that this units had. Volume control has high gain, meaning sensitive iem or headphones might have the problem driving properly as volume potentiometer will be below 9am creating channel imbalance. Also, I have noticed when listening music at 80db lvl let say louder there is some upper mid shoutiness. Unit is fine for a price, had get rid of mine and went for two separate components not turning back. I liked R2R dac though, felt warminsh and deep not the most detailed but fine for a price.

 

[delfin150]

Can anyone compare ef400 with xduoo ta-22? Both have similar price tag and sound signature.

 

[Polky74]

Can anyone compare ef400 with xduoo ta-22? Both have similar price tag and sound signature.

I think it's also important what kind of headphones you want to use them with... I think the Hifiman is more musical because of the R2R while the XDUOO is more analytical because of the ESS delta/sigma chip.

 

[Hyde00]

Anyone manage to compare EF400 with EF499 or EF500 yet?

 

[delfin150]

@Polky74 I want to pair it with audeze lcd2c and prefer a mixture of fun and organic sound. Ta-22 has a tube amp, generally sounds somewhere in between analog and analytical ess sound. The only thing I’m concerned is, that tubes/r2r will muffle the sound even more, than it already is