[metalmilitia16]

Hi, I want to buy an amp for my hifiman arya se, I'm stuck between fiio k9 pro ess and hifiman ef 400, the only thing that matters to me is sound quality, which one should I choose? Thanks.

 

[elira]

Elira, thank you for your reply.

My seller is also in contact with FiiO, they responded:

"It sounds like the customer isn't fully inserting the Pentaconn connector."

The reply gave me an idea, so I did a test:
When slowly inserting the 4.4mm connector, you can hear different channels playing on the headphones as the connector is being plugged in. First the left channel(low volume), then right channel(low volume), then left channel(high volume), and in the end BEFORE THE PLUG "CLICKS" INTO PLACE you can hear both channels at high volume. At this point I have the full volume available to me at L/M/H gain. But if I push the connector all the way, it will stop playing after a 1-2 second delay and the red LED ring will start pulsating.

So funny enough the device works better if the 4.4mm connector is NOT plugged in all the way.

I know this is not intended use, but I found it interesting.

Cheers

That's an out of spec connector, very likely on the cable. Those work in some sockets but have issues in others. You need a new cable.

 

[Ichos]

Hi, I want to buy an amp for my hifiman arya se, I'm stuck between fiio k9 pro ess and hifiman ef 400, the only thing that matters to me is sound quality, which one should I choose? Thanks.

Hi, you can read a couple of reviews, like mine to help you make up your mind.

https://www.head-fi.org/showcase/hifiman-ef400.25881/review/29050/

https://www.head-fi.org/showcase/fiio-k9-pro-ess.25882/review/28610/

 

[Marlowe]

Hi, you can read a couple of reviews, like mine to help you make up your mind.

https://www.head-fi.org/showcase/hifiman-ef400.25881/review/29050/

https://www.head-fi.org/showcase/fiio-k9-pro-ess.25882/review/28610/

I knew you had reviewed both amps and was thinking of posting the links in response, but you beat me to it. Both were informative reviews, and both amps have received almost unanimously good to rave reviews, but I'm seriously thinking of getting the FiiO early next year (when I get the funds, LOL). Although the EF400 would undoubtedly pair well with my Arya Stealth, the almost complete lack of features on the Hifiman, lacking even basic inputs any amp in that price class should have, is a non-starter for me.

 

[Ichos]

I knew you had reviewed both amps and was thinking of posting the links in response, but you beat me to it. Both were informative reviews, and both amps have received almost unanimously good to rave reviews, but I'm seriously thinking of getting the FiiO early next year (when I get the funds, LOL). Although the EF400 would undoubtedly pair well with my Arya Stealth, the almost complete lack of features on the Hifiman, lacking even basic inputs any amp in that price class should have, is a non-starter for me.

For slightly more warm and organic sound signature it is the EF400.
Strictly neutral but not sharp or fatiguing and still enjoyable the K9 PRO.
Feature - wise the FiiO beats the HiFiMan hands down.

 

[llysender]

For slightly more warm and organic sound signature it is the EF400.
Strictly neutral but not sharp or fatiguing and still enjoyable the K9 PRO.
Feature - wise the FiiO beats the HiFiMan hands down.

Interesting at lest on my end A/Bing the EF400 and the K9 Pro ESS I would consider the K9 pro slightly bright tilted neutral but the EF400 on the other hand is a U shape with a very noticable boost to the lower treble. While both have quite the smooth attack peak the decay on the K9 pro is quite fast and natural sounding as apposed to the stretched out decay of the EF400.

If you want a fun thicker sound and dont mind the highs boost(which I agree fits alot of the hifiman planars just not their dyanamics sadly) the EF400 is the way to go. Being a thin microdetails sound guy the EF400 is sadly lacking in that department with it not being able to grip the driver like a vice but that makes planars sound less like a layered stack of cards kind of sound so I can understand why hifiman went in that direction.

Oh yeah @FiiO any plans on bringing back the K9 pro AKM with the 4499EX chip preferably with the improvements made to the ESS version?

 

[kRed]

Having both those combo dac/amp, I tend to use the K9 with the Arya more.
I think it strengthens the Arya SE features, giving them more air and space, presenting that wall of sound feeling better than the ef400.

The EF400 to me sounds less neutral, more analog and less “perfect”.

They are both great, of course as @Ichos said feature wise the FiiO is on another league, and it also seems to be way more easy to use.
For example I can plug a usb c cable on the fly and use that, while switching between a usb b connection and the coaxial input.

If I plug the usb c cable in the ef400 without powering it off and removing the usb b cable it just freezes and need an hard reset.

 

[dlelikov]

I had a K9 Pro ESS, then I sold it and bought an EF-400. The EF-400, thanks to its AB class amplifier, sounds fatter, more natural, with a much wider and deeper stage. But with fewer micro-details than the K9 with its THX amplifier. I also compared the DAC from the ef 400, against the sms su-10 on two ESS 9038 Pro, both connected to the Topping A90D. I couldn't distinguish the sound of these DACs, for me they sound exactly the same and transparent. Therefore, the best purchase will be for K9 Pro + Classes A amp (Sing[er SA-1), or EF400 + Topping A90D (or any THX amp).

 

[FiiO]

Interesting at lest on my end A/Bing the EF400 and the K9 Pro ESS I would consider the K9 pro slightly bright tilted neutral but the EF400 on the other hand is a U shape with a very noticable boost to the lower treble. While both have quite the smooth attack peak the decay on the K9 pro is quite fast and natural sounding as apposed to the stretched out decay of the EF400.

If you want a fun thicker sound and dont mind the highs boost(which I agree fits alot of the hifiman planars just not their dyanamics sadly) the EF400 is the way to go. Being a thin microdetails sound guy the EF400 is sadly lacking in that department with it not being able to grip the driver like a vice but that makes planars sound less like a layered stack of cards kind of sound so I can understand why hifiman went in that direction.

Oh yeah @FiiO any plans on bringing back the K9 pro AKM with the 4499EX chip preferably with the improvements made to the ESS version?

Dear friend,

Thanks for the feedback. We do not have this plan currently but we will report your feedback to the product manager.

Best regards

 

[EdgeDC]

This came up over in the FiiO K7 thread, but it made sense to post about it here, also. I did not learn about this until today, but apparently FiiO made a special limited edition (200 units) of the K9 Pro ESS, with a transparent acrylic top, so that you can see all of the electronics inside. Pretty cool. Unfortunately they seem to have only released it for the Chinese market, and the only way to get one outside China is to buy from an unauthorized reseller - BrightAudio Store on AliExpress has just one left.

Thanks to user @scracy for the added info link from the FiiO China page - it requires translation from Chinese though:

Limited to 200 units! K9 Pro ESS Sunroof Discovery Edition shocking launch! -FiiO---BORN FOR MUSIC

It's either called the "Skylight" version (per BrightAudio Store), or the "Sunroof Discovery Edition" (per the Google-translated link above). I'm not sure which is the correct name that was intended by FiiO, as Google translation can be a bit weird sometimes.

It looks pretty darn cool. Here's a pic of it, snagged from the listing on AliExpress:

 

[Ichos]

Very beautiful, I love it when I can see the internals!

 

[PitSteelers69]

Does anyone know if the Op-Amps are socketed? I'd like to try rolling Op-Amps to see if it makes any difference.

 

[armstrj2]

Does anyone know if the Op-Amps are socketed? I'd like to try rolling Op-Amps to see if it makes any difference.

I read in a review before that they are not but I haven't confirmed that.

 

[PitSteelers69]

I read in a review before that they are not but I haven't confirmed that.

I don't want to take mine apart just to check.

 

[elira]

Does anyone know if the Op-Amps are socketed? I'd like to try rolling Op-Amps to see if it makes any difference.

They probably aren’t and I don’t think it would be wise to replace them. Those THX amplifiers are designed very tightly and all the parts are specific for that design.