[Johnfg465vd]

Hello, I got my brand new EF400 yesterday, a while ago I finally connected the device to my laptop via usb B and started a few random listens. I have read that as many other R2R DACs, the EF400 is no different in requiring a break-in period so, even if I'm already enjoying its sound signature, I will not add further comments about that at the moment.
One thing I immediately noticed, however, which is the weird behaviour of its power output. At first I was like...is this really the powerful amp they claim to be? A Sennheiser HD800S was connected to the amp, and I needed to push the volume dial up to 3PM in high gain to have a decent - not even loud - output. I changed usb port, then also the cable, and finally I also tried the EF400 on a different laptop...nothing happened. Always a low, unengaging volume level. Just out of curiosity, I decided to switch to usb C and to use my Android phone...boom! 10AM on low gain and loud!
If I'm not wrong, other people have experienced similar issues. How did you manage to solve them? Thanks in advance.

I have this issue and have not found a solution to it (tested 2 different units). In my case, there's low volume when pairing an android phone or DAP via a Type-C to Type-C Cable (tried different cables). Using a Type-A to Type-B Cable while connected to my PC works as it should. The good thing for me is that I only use the EF400 at the desk paired to my PC so this has not been a big problem for me.

Are you using a Type-C to Type-B Cable? maybe try a Type-A to Type-B and see if that fixes your problem.

 

[Metal-Fi]

Thanks for your replies. I think the issue does not depend on the EF400 but maybe is software-related.
I tested both the Usb inputs of the EF400. With my laptop, I used both Usb A to B and A to C cables, but the low-volume problem remained. With my smartphone, I used a Usb C to C but also a Usb A to B with a type-C otg adapter: strong and engaging output in both cases. I assume there is some audio mis-configuration affecting my system (Linux OS). Not sure why this has never happened with other DACs, by the way...

 

[Johnfg465vd]

Thanks for your replies. I think the issue does not depend on the EF400 but maybe is software-related.
I tested both the Usb inputs of the EF400. With my laptop, I used both Usb A to B and A to C cables, but the low-volume problem remained. With my smartphone, I used a Usb C to C but also a Usb A to B with a type-C otg adapter: strong and engaging output in both cases. I assume there is some audio mis-configuration affecting my system (Linux OS). Not sure why this has never happened with other DACs, by the way...

It's an issue with whatever USB chip they are using in the EF400. It's nothing software related or due to Cables.

 

[Metal-Fi]

The weird thing is that the Dac/Amp works properly on both Usb inputs when they are connected to the smartphone, and both show the same issue when I switch to laptop. Just to be sure, in the meantime I have contacted Hifiman's customer support, hopefully they can give more insight into this problem.

 

[Hyde00]

lol sounds like you guys have the opposite findings, like android works on one person but not the other, then computer works on one person but not the other.

But I'm guessing one of you is on Windows PC the other on Linux? We need a MacOS person to test this LOL.

 

[Johnfg465vd]

lol sounds like you guys have the opposite findings, like android works on one person but not the other, then computer works on one person but not the other.

But I'm guessing one of you is on Windows PC the other on Linux? We need a MacOS person to test this LOL.

Yeah, I'm on Win 11. Which reminds me of something, if there's anyone who is experiencing random pauses (a few milliseconds), uninstall the HiFiMan USB Drivers if you installed them. I started experiencing this problem as soon as I installed the drivers and it went away after I uninstalled them.

 

[Brain Damage]

I definitely get more than ample power from laptop (older Samsung) to EF400 playing Audirvana via USB A to USB C. From both my android phones and my android tablet, the power is far less and the potentiometer on the EF400 needs turned way up.

 

[Metal-Fi]

I had an email conversation with Hifiman's customer service. As I expected, their technical staff claimed that my type of issue is an "odd" behavior, as the Dac/Amp works properly from both Usb inputs when a smartphone is connected, and the volume problem shows only when I'm using a laptop. This is indeed different from what other users have experienced, namely a lower/higher volume output based on the specific Usb input in use. My idea is that there must be something wrong in my laptop configuration, so I will continue testing to see if I'm able to spot a workaround...

 

[gordon0986]

Thanks for this. Looking to upgrade from my iFi Micro iDSD BL for use with Ether2 and was strongly considering the EF400. This is the first I've heard of the EF400 being light on the bass and lacking oomph. Anyone else care to chime in on this aspect of the EF400's sound?

Also would have expected the XLR out to have the most weight of the various headphone outputs based on the specs and description by Hifiman.

Would you have any idea if a separate Dac would pair with the EF 400! I have the Gustard X26 pro Dac! But don’t want to buy another amp to pair with it. If so what cables would I need to connect them both

 

[Johnfg465vd]

Would you have any idea if a separate Dac would pair with the EF 400! I have the Gustard X26 pro Dac! But don’t want to buy another amp to pair with it. If so what cables would I need to connect them both

There are no Analogue Inputs on the EF400 so there is no way to pair an external DAC to it. You can only pair an external Amp to it and use it's (EF400) DAC section but cannot use it only as an Amp paired to some other DAC.

 

[Riversalt]

Anyone in the US thinking of selling their EF400 of the latest bug free models?
PM me best offer.

sold finished.

 

[Johnfg465vd]

Fellow EF400 users, I've been using the RCA Outs to pair my Active Speakers but now I'm considering getting some XLR Cables, is there going to be an improvement with XLR Outs on the back? I'm familiar with the improvement in sound when using Balanced Headphone Outputs on the front but what about Line-Outs? My speakers only has RCA Input so I'll be getting XLR to RCA Cables.

 

[Riversalt]

@TeamHiFiMAN

3 versions linear capacitors?

Capacitors Lelon e SamXon.


Would this be the reason for the defects reported before and listen to 3 silent updates?
Why not use Nichicon, Rubycon etc?
I think a good recape should further improve the quality and reliability of the Ef400.

 

[Riversalt]

Fellow EF400 users, I've been using the RCA Outs to pair my Active Speakers but now I'm considering getting some XLR Cables, is there going to be an improvement with XLR Outs on the back? I'm familiar with the improvement in sound when using Balanced Headphone Outputs on the front but what about Line-Outs? My speakers only has RCA Input so I'll be getting XLR to RCA Cables.

How many people here in the EF400 group still have their units working well?
Guys stopped posting around here is this a good sign that you are enjoying your EF400 units without previous problems?

 

[Johnfg465vd]

How many people here in the EF400 group still have their units working well?
Guys stopped posting around here is this a good sign that you are enjoying your EF400 units without previous problems?

I don't know about others but my unit is working well without any issues when it comes to Desktop use. I mostly use it with Headphones but even with IEMs (IE 600, XENNS UP..., I get decent usable volume range (using 4.4 Out). The sound quality is good enough that I don't feel the need to upgrade (it's been 1 year since I got the EF400) even after trying some higher priced DAC/Amps.

In terms of issues, I have the USB issue when pairing it to an Android phone or DAP where you get low volume out of the Headphone Outs but since I only use the EF400 paired to my PC, this is not an issue for me.