Feliks-Audio EUFORIA - A Wolf in "Sheep's" Clothing...
May 4, 2021 at 8:13 PM Post #9,226 of 9,285

LoryWiv

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Nice, @incredulousity. I love your spirit of adventure to get the most out of Euforia without blowing anything up. :pray:
On a related note, I posted a question in the fairly quiet Elise forum about compatibility, no answers and I'm itching to try the EL37 so I'll put it to the smart people on this FA forum, since I believe Elise and Euforia have similar design and electric specifications.

The question is about Elise's (or Euforia's) auto-bias circuitry and how that affects compatibility with non-standard tubes. Specifically, I am interested in trying Mullard EL37 which Deyan has assured me his 6L6 to 6AS7 adapters accommodate. However, reading here it states that these tubes can substitute for 6L6"as long "as your amp does not put more than 360 volts on the plate and 270 volts at 2.5 watts on the screen." I am not certain how to get this information for Elise (or Euforia) nor if it is even applicable with auto-bias and the EL37 tubes running triode-strapped in adapters. Lastly, while I plan to use the EL37 in power (output) slots, would it be safe to try them as drivers since my understanding is that auto-bias circuitry is applied to power slots, unsure if to driver slots as well.

Perhaps I am worrying too much but would love to learn regarding these questions both the principles and data to be mindful of, as well as know if others have run EL37 successfully in power / driver slots with Elise or Euforia. Thanks for any info.! :thumbsup:
 
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May 5, 2021 at 6:27 AM Post #9,227 of 9,285

JTbbb

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Just a heads up to fellow Euforia AE owners, and possibly Euforia/Elise owners. I have lost my LH channel and had got it into my head it was something I had caused when installing a power tube. Well, it is being looked at by a valve amp specialist and it’s turned out to be the Jack Plug socket that is falling apart. My amp is 14 months old.
 
May 10, 2021 at 4:02 PM Post #9,229 of 9,285

Deleeh

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Hi Dear friends , I have finally managed to get a translation of my original Feliks Audio Euforia review.

https://www.head-fi.org/showcase/feliks-euforia-tube-amplifier-6sn7-6n13s.24351/review/25842/

Feel free to comment and let me know if you like it!
Hello,

I don't quite agree with the test.
The Euforia is a bit more in that respect.

The Euforia is more than capable of handling the Audeze Lcd 2 C, which has 80 ohms.
What you should know is that you can't get the best out of the Ps Vane tubes.
The Lcd 2 C sounds a bit bloodless. But if you replace the 6SN7 with better tubes, the Lcd 2 C really ignites. (Lin Lai E-6SN7)
With the Mullard 6080s, things really take off. 6080 Sylvania tubes are also very good in this pairing.
The bass is even more, mids and highs remain on the same level as the Ps vane.
But the mids and highs are a bit more relaxed with the Parrung Lin Lai E-6SN7 and 6080 Mullards or the 6080 Sylvania.
The Sylvania are a touch more organic but don't go quite as low as the Mullards.

And with the original pairing I have to say the 6AS7G tubes are clearly worse.
I swapped the original Rusis for the Rca and found that both masked certain areas.

So it gives the impression why you should listen to it with "high end" headphones.

My recommendation is to save the 200€/$ and invest in the right tubes. If you are willing to spend 50-60 €/$ more then the Lin Lai and Sylvania 6080s you have already done a lot.

Then the Euforia will also run extremely well with a Denon D2000 Fostex tr 00.

Apart from that, you can pair the Euforia with other tubes but it is not recommended.

In the beginning I was quite disappointed with the Euforia.
In the meantime, however, no more. More than satisfied.
I think that it will also harmonise with a less good Dac and headphones with the most common ones.

I had an Hd 600 here for a short time and I didn't like it as much with the original tube pairing as I do with the Lcd 2 c.
If I had kept it, it would probably cut a good figure after the tube replacement.
The bass was a bit crisper than the Lcd 2c, but the Lcd 2c had the better mids and highs.
And with the replacement of the original tubes, the Eq setting was completely removed.
Another certain point I wanted to address.

What I was missing in the test was the pairing with the Denafrips Ares 2.
How good it sounds and where you could put it?

But I didn't want to ruin the test, I just wanted to show what the Euforia is and what it deserves.

And by the way, I was allowed to test an Otl in the same price range from a manufacturer.
3 guesses who won the test?
It was the Euforia with its Lin lai + Sylvania pairing.

The Otl from the manufacturer was too aggressive for me, I got tired of listening to it very quickly, and it was slightly peaked in the highs.
The Euforia was much softer and more affectionate in sound.

Thanks anyway for all the impressions of your test. :wink:
 
May 10, 2021 at 4:12 PM Post #9,230 of 9,285

Ichos

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Hello,

I don't quite agree with the test.
The Euforia is a bit more in that respect.

The Euforia is more than capable of handling the Audeze Lcd 2 C, which has 80 ohms.
What you should know is that you can't get the best out of the Ps Vane tubes.
The Lcd 2 C sounds a bit bloodless. But if you replace the 6SN7 with better tubes, the Lcd 2 C really ignites. (Lin Lai E-6SN7)
With the Mullard 6080s, things really take off. 6080 Sylvania tubes are also very good in this pairing.
The bass is even more, mids and highs remain on the same level as the Ps vane.
But the mids and highs are a bit more relaxed with the Parrung Lin Lai E-6SN7 and 6080 Mullards or the 6080 Sylvania.
The Sylvania are a touch more organic but don't go quite as low as the Mullards.

And with the original pairing I have to say the 6AS7G tubes are clearly worse.
I swapped the original Rusis for the Rca and found that both masked certain areas.

So it gives the impression why you should listen to it with "high end" headphones.

My recommendation is to save the 200€/$ and invest in the right tubes. If you are willing to spend 50-60 €/$ more then the Lin Lai and Sylvania 6080s you have already done a lot.

Then the Euforia will also run extremely well with a Denon D2000 Fostex tr 00.

Apart from that, you can pair the Euforia with other tubes but it is not recommended.

In the beginning I was quite disappointed with the Euforia.
In the meantime, however, no more. More than satisfied.
I think that it will also harmonise with a less good Dac and headphones with the most common ones.

I had an Hd 600 here for a short time and I didn't like it as much with the original tube pairing as I do with the Lcd 2 c.
If I had kept it, it would probably cut a good figure after the tube replacement.
The bass was a bit crisper than the Lcd 2c, but the Lcd 2c had the better mids and highs.
And with the replacement of the original tubes, the Eq setting was completely removed.
Another certain point I wanted to address.

What I was missing in the test was the pairing with the Denafrips Ares 2.
How good it sounds and where you could put it?

But I didn't want to ruin the test, I just wanted to show what the Euforia is and what it deserves.

And by the way, I was allowed to test an Otl in the same price range from a manufacturer.
3 guesses who won the test?
It was the Euforia with its Lin lai + Sylvania pairing.

The Otl from the manufacturer was too aggressive for me, I got tired of listening to it very quickly, and it was slightly peaked in the highs.
The Euforia was much softer and more affectionate in sound.

Thanks anyway for all the impressions of your test. :wink:
As you can understand a review can't cover various tube rolling options.
That is why user feedback like yours is really valuable.

Now on a second thought I am going to remove the part about high end partners so I don't discourage people from buying and experimenting with the Euforia.

Regarding the Ares II , as you understand this is not an Ares review so I can't expand more.

Kindly read here my Pontus review Pontus and think of Ares as a slightly scaled down version.

If you like natural sounding DACs and hate DS glare and ringing as much as I do then you should definitely consider the Ares.
 
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May 10, 2021 at 4:25 PM Post #9,231 of 9,285

mordy

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As you can understand a review can't cover various tube rolling options.
That is why user feedback like yours is really valuable.

Now on a second thought I am going to remove the part about high end partners so I don't discourage people from buying and experimenting with the Euforia.
In the second review (looks like a different reviewer) there was a statement about tube longevity that I don't agree with:

There is a statement in that review that is incorrect: "You should keep in mind that most tubes are rated for a life of around 1000 hours, so you'll need a few if you're to use a tube amplifier. This doesn't mean that the amplifier will die after 1000 hours, but you will have to replace the tubes."

Most tubes are rated for 3000 - 5000 hours, and many are rated for 10.000 hours of use. Many tubes used today were originally intended for military use, and the more benign usage in a headphone amplifier can make tubes last for many years - up to ten years and more.
There is a perception that only new tubes (NOS) can sound good and that they have to measure new or almost new to sound good. This is not true - even a lower measuring tube could sound just as good as a high measuring tube.

The service life of a good quality headphone amp could approach twenty years or more.

But you do need more tubes for a different reason - once you have a tube headphone amplifier you can change the sound with different tubes, often to an amazing degree and hopefully find the sound that you really like.
 
May 10, 2021 at 4:32 PM Post #9,232 of 9,285

Ichos

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In the second review (looks like a different reviewer) there was a statement about tube longevity that I don't agree with:

There is a statement in that review that is incorrect: "You should keep in mind that most tubes are rated for a life of around 1000 hours, so you'll need a few if you're to use a tube amplifier. This doesn't mean that the amplifier will die after 1000 hours, but you will have to replace the tubes."

Most tubes are rated for 3000 - 5000 hours, and many are rated for 10.000 hours of use. Many tubes used today were originally intended for military use, and the more benign usage in a headphone amplifier can make tubes last for many years - up to ten years and more.
There is a perception that only new tubes (NOS) can sound good and that they have to measure new or almost new to sound good. This is not true - even a lower measuring tube could sound just as good as a high measuring tube.

The service life of a good quality headphone amp could approach twenty years or more.

But you do need more tubes for a different reason - once you have a tube headphone amplifier you can change the sound with different tubes, often to an amazing degree and hopefully find the sound that you really like.
Most tubes are rated for more than 3K hours unless they are run at very high voltage and current reaching their limit.

Tube amplifiers have some disadvantages compared to solid state that their happy owners usually don't mind.

I used to be on the tube rolling pit myself and I have swear to myself not to roll again.

For the Euforia I have only bought a pair of cheap 6080w power tubes.
 
May 10, 2021 at 4:43 PM Post #9,233 of 9,285

mordy

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Most tubes are rated for more than 3K hours unless they are run at very high voltage and current reaching their limit.

Tube amplifiers have some disadvantages compared to solid state that their happy owners usually don't mind.

I used to be on the tube rolling pit myself and I have swear to myself not to roll again.

For the Euforia I have only bought a pair of cheap 6080w power tubes.
You are right - tube rolling is addictive. I try to limit myself by not allowing myself to buy tubes for more than $6 each including shipping.
Here is a toungue-in-cheek tube aduiophile saying:
"I am drawn to tube amplifiers because of the expense, unpredictability and inconvience."
But all jokes aside, the rewards are there....
 
May 10, 2021 at 7:33 PM Post #9,235 of 9,285

mordy

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Unfortunately with $6 per tube , you can't tube roll the Euforia...
Well, I have to admit that the adapters (and power supplies) will cost more than the tubes, but check the prices on GU50 tubes (I don't have them).
My present amp is using driver tubes that cost less than $6 and power tubes that cost around $9 but admittedly it takes time and patience to find these deals. I am using 6J5GT tubes as drivers and 6N12S tubes as power tubes, and these tubes could be used in the Euforia (the 6J5 with 6N7 to 6SN7 adapters).
Bottom line: You do not need expensive tubes for good sound!
 
May 13, 2021 at 11:43 AM Post #9,236 of 9,285

JTbbb

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Just a heads up to fellow Euforia AE owners, and possibly Euforia/Elise owners. I have lost my LH channel and had got it into my head it was something I had caused when installing a power tube. Well, it is being looked at by a valve amp specialist and it’s turned out to be the Jack Plug socket that is falling apart. My amp is 14 months old.

Got my amp back yesterday after losing the LH channel, and all is restored. I missed it! Although the jack socket was indeed well worn it turned out not to be the culprit for losing the LH channel. The jack socket is connected to a small solid state PCB and one of it’s purposes is to allow a small time delay before switching the output to the headphones socket. Surface mounted is a small switching relay which does the switching, and it was this that had failed.

I did of course contact Feliks Audio when I first lost the channel as I knew it could be returned for investigation and repair, but they advised it would be an unknown undertaking now that the UK we’re not part of the EU. Fortunately I came across Dave who runs Classic Valve Amps, just north of Nottingham, who I cannot recommend highly enough, excellent chap, excellent service.
 
May 19, 2021 at 5:20 AM Post #9,237 of 9,285

Laines

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Just got my Euforia and want to try some 6080 tubes.
I realized that the base of the 6080 is way to big for the hole in the euforia. I mean the pins are inserted but just about half way.

How you guys do it? Are you using a adapter?
 
May 19, 2021 at 6:58 AM Post #9,239 of 9,285

Laines

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Odd, post some pics. I have used many pairs of 6080’s with no issues at all.
Sure,

The original tube (rigth) has a smaller diameter and fits perfectly in the tube opening at the Euforia.
The 6080 has a larger diameter and sits on top of it. So the pins of the 6080 are not fully "connected"
1621421582791.png


1621421690699.png
 
May 19, 2021 at 7:32 AM Post #9,240 of 9,285

JTbbb

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Sure,

The original tube (rigth) has a smaller diameter and fits perfectly in the tube opening at the Euforia.
The 6080 has a larger diameter and sits on top of it. So the pins of the 6080 are not fully "connected"
1621421582791.png

1621421690699.png

I’ve never seen one with that circumference, I think others will be able to chime in. But going back to your original query, I can’t see there being any harm done as long as the pins are making sufficient contact.
 

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