The (Un)Official Amp Thread For ZMF Headphones
Mar 15, 2023 at 10:37 AM Post #1,291 of 3,357
I don't disagree wtih this review. It says:

"Compared to the HA2-SF, the new one, the Euforia is a bit slower, smoother, warmer. Body-wise they’re actually very similar, but the HA2-SE is more neutral, more spacious, cleaner and more energetic. Especially the top end of the Euforia is softer compared to the HA2-SF (it’s more like the HA2-SE).

The Euforia and the HA2-SE/SF each have things they’re really good at, but if I have to rank them I would say SF > Euforia > SE. You could however prefer the more tubish sound of the Euforia, but looking at the technicalities, the Auris Audio HA2-SF is the clear winner in my humble opinion"

Now, ignore the writer's conclusion, which is already based on a preference, and look at the actual comparison of character, that is pretty spot on. For the more tube like OTL sound that is smoother and warmer, go with the Euforia. For that more clean and neutral linear amplification go with the Auris.

It depends what you are looking for!
I’m wondering how newish Feliks EVO would compare as it is an evolution of the Euphoria platform with some boutique bits, right? and if this could flip the paradigm.
 
Mar 15, 2023 at 10:55 AM Post #1,292 of 3,357
I’m wondering how newish Feliks EVO would compare as it is an evolution of the Euphoria platform with some boutique bits, right? and if this could flip the paradigm.

I only ever heard the new EVO. Purely guess, but I'm pretty sure they'd all sound similar.
 
Mar 15, 2023 at 11:32 AM Post #1,293 of 3,357
I’m wondering how newish Feliks EVO would compare as it is an evolution of the Euphoria platform with some boutique bits, right? and if this could flip the paradigm.
I much prefered the EVO over the Elise/Euforia when demo-ing. I have not yet heard the Euforia Evo though, so i can't give you any comparisions there.

p.s: the amp is not truly balanced, the XLR out is for convienience only.
 
Mar 15, 2023 at 9:24 PM Post #1,294 of 3,357
Running Cetron 6336B & Osram L63 in the Blue Halo+ today.

With 6336 being equivalent to 2x 6080, the output impedance is around 35 Ohm. This puts the damping factor right around 8.5:1 with the Verite Closed.

They sound excellent. Fast, tight, spacious, impactful, with a tasteful amount of tube tone. As they say "ZMF neutral", I think this sounds like "1101 neutral".

These chunky tubes are mini-space heaters. However with the fans running at 40% speed, internal ambient temps are a cool 100° F.

2023-03-15_16.56.15 2.jpg

2023-03-15_17.03.19.jpg

2023-03-15_16.45.40.jpg
 
Mar 15, 2023 at 9:36 PM Post #1,295 of 3,357
Running Cetron 6336B & Osram L63 in the Blue Halo+ today.

With 6336 being equivalent to 2x 6080, the output impedance is around 35 Ohm. This puts the damping factor right around 8.5:1 with the Verite Closed.

They sound excellent. Fast, tight, spacious, impactful, with a tasteful amount of tube tone. As they say "ZMF neutral", I think this sounds like "1101 neutral".

These chunky tubes are mini-space heaters. However with the fans running at 40% speed, internal ambient temps are a cool 100° F.



Very few amps can handle the 6336. In addition to your amp, the Glenn OTL takes them and I think @L0rdGwyn Spinosaurus OTL takes them as well.
As you noted, the 6336 drops the impedance and were my go to tubes for low impedance dynamic driver headphones, as well as planars when I had the GOTL.

Speaking of esoteric tubes, I'm running a pair of Tung Sol 7802 in the Airmid tonight w/ a pair of Westinghouse branded National Union 6J5s. Lovely clean, tight sound with the Atrium closed.

EDIT: Those Osrams are clean looking! Did you grab them from Billington?
 
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Mar 15, 2023 at 10:07 PM Post #1,296 of 3,357
Very few amps can handle the 6336. In addition to your amp, the Glenn OTL takes them and I think @L0rdGwyn Spinosaurus OTL takes them as well.
As you noted, the 6336 drops the impedance and were my go to tubes for low impedance dynamic driver headphones, as well as planars when I had the GOTL.
Compared to top tier 6AS7G and 6080s they are tremendous value for the price with how good they sound. I don’t have any planars yet but am eager to try. I’m pretty sure all 6336 were the same manufacturer (?) so not much rolling options tho.

Speaking of esoteric tubes, I'm running a pair of Tung Sol 7802 in the Airmid tonight w/ a pair of Westinghouse branded National Union 6J5s. Lovely clean, tight sound with the Atrium closed.
Ahhh the unobtainum tubes. Enjoy the roll!

EDIT: Those Osrams are clean looking! Did you grab them from Billington?
Thanks! I was quite pleased the labels are both facing directly forward :) These are actually two singles from different eBay sellers that turned out to be a perfect match aesthetically/sonically. I have a pair from Billington also but the stickers are in worse shape.

As an aside, I’ve noticed the sizes of GEC L63 can vary substantially even with the same labels. I had a different Osram L63 with the same sticker at first (pic below) and realized it was almost a full inch taller. The sticker was also in a different spot (Out of view from the front). The internals appear to be the same, which makes me curious why such a big discrepancy between bottle heights.
F4169CFC-012A-4E13-BB10-11BAFB73CB37.jpeg
 
Mar 15, 2023 at 10:23 PM Post #1,297 of 3,357
Compared to top tier 6AS7G and 6080s they are tremendous value for the price with how good they sound. I don’t have any planars yet but am eager to try. I’m pretty sure all 6336 were the same manufacturer (?) so not much rolling options tho.
I had a Chatham labled pair and a pair labled Cetron. My buddy down in Tennessee was telling me the other night that the Russians made a 6336 equivalent too.
Ahhh the unobtainum tubes. Enjoy the roll!
Yeah ridiculously difficult to find. Like the 6336, the 7802 drops the impedance. The AC's sub bass sounds downright neutral with the lambskin pads on. Super 3D too. I'm guessing the 6336s might have a similar effect on the AC as well.
Thanks! I was quite pleased the labels are both facing directly forward :) These are actually two singles from different eBay sellers that turned out to be a perfect match aesthetically/sonically.
Damn dude, do you play the lottery?!
As an aside, I’ve noticed the sizes of GEC L63 can vary substantially even with the same labels. I had a different Osram L63 with the same sticker at first (pic below) and realized it was almost a full inch taller. The sticker was also in a different spot (Out of view from the front). The internals appear to be the same, which makes me curious why such a big discrepancy between bottle heights.
I have a pair of Zenith 6c5gt with a height disparity as well.
 
Mar 15, 2023 at 10:34 PM Post #1,298 of 3,357
Very few amps can handle the 6336. In addition to your amp, the Glenn OTL takes them and I think @L0rdGwyn Spinosaurus OTL takes them as well.
As you noted, the 6336 drops the impedance and were my go to tubes for low impedance dynamic driver headphones, as well as planars when I had the GOTL.

Speaking of esoteric tubes, I'm running a pair of Tung Sol 7802 in the Airmid tonight w/ a pair of Westinghouse branded National Union 6J5s. Lovely clean, tight sound with the Atrium closed.

EDIT: Those Osrams are clean looking! Did you grab them from Billington?

Yeah I actually use the 6528 more often though, it's the higher transconductance cousin of the 6336, definitely worth a try. Higher transconductance = lower output impedance.
 
Mar 15, 2023 at 10:49 PM Post #1,299 of 3,357
Yeah I actually use the 6528 more often though, it's the higher transconductance cousin of the 6336, definitely worth a try. Higher transconductance = lower output impedance.
I think I have a pair of those as well - didn't realize they had different specs. I'll have to give those a shot next to see if I can hear a difference in this amp. Thanks for the tip!
 
Mar 16, 2023 at 7:55 AM Post #1,300 of 3,357
Running Cetron 6336B & Osram L63 in the Blue Halo+ today.

With 6336 being equivalent to 2x 6080, the output impedance is around 35 Ohm. This puts the damping factor right around 8.5:1 with the Verite Closed.

They sound excellent. Fast, tight, spacious, impactful, with a tasteful amount of tube tone. As they say "ZMF neutral", I think this sounds like "1101 neutral".

These chunky tubes are mini-space heaters. However with the fans running at 40% speed, internal ambient temps are a cool 100° F.

2023-03-15_16.56.15 2.jpg
2023-03-15_17.03.19.jpg
2023-03-15_16.45.40.jpg
I have a set of the same tubes, but the labels don't face forward....that is quite rare!
 
Mar 16, 2023 at 4:21 PM Post #1,301 of 3,357
Recently managed to grab an iha-1 from a fellow headfier and also got a metal base rectifier and kenrads. This combo is bliss with the atrium and verite
 

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Mar 17, 2023 at 2:23 AM Post #1,302 of 3,357
Hi All quick update from my end. Took day off to visit my local retailers to demo few solid states and some tube amps.

I’m no audiophile and possibly won’t be able to express properly interms of what I’m exactly hearing but in summary tried the following.

Burson Soloist 3X GT- very clean detailed widest soundstage

IFI can Pro Signature- sounds closer to tube amp warm tilt. Solid state setting was the best in my opinion. Vocals are upfront on this compared to rest of the music elements.

Auris HA2 SF -warm and natural good detail bass qty is good but not impactful like SS

Auris Nirvana expensive does everything well much much better than HA2 SF as the price suggests.

Violectric V550 did a/b a lot and this was the sound I was after. Well balanced good amount of detail while never sounding clinical or harsh. Vocals sounded amazing and instrument separation very comparable to Burson. Plus hearing so much about tube rolling,costs and availability made me think twice in investing in tube amps. Also to me ZMF Atruims sounded the best with V550 and bass impact was next level. I personally think Violectric is a great all rounder.

This is my amateur description of what I experienced.

Won’t list source as I used quite a few.

Thanks again to everyone for their suggestions.
 
Mar 17, 2023 at 6:04 AM Post #1,303 of 3,357
Hi All quick update from my end. Took day off to visit my local retailers to demo few solid states and some tube amps.

I’m no audiophile and possibly won’t be able to express properly interms of what I’m exactly hearing but in summary tried the following.

Burson Soloist 3X GT- very clean detailed widest soundstage

IFI can Pro Signature- sounds closer to tube amp warm tilt. Solid state setting was the best in my opinion. Vocals are upfront on this compared to rest of the music elements.

Auris HA2 SF -warm and natural good detail bass qty is good but not impactful like SS

Auris Nirvana expensive does everything well much much better than HA2 SF as the price suggests.

Violectric V550 did a/b a lot and this was the sound I was after. Well balanced good amount of detail while never sounding clinical or harsh. Vocals sounded amazing and instrument separation very comparable to Burson. Plus hearing so much about tube rolling,costs and availability made me think twice in investing in tube amps. Also to me ZMF Atruims sounded the best with V550 and bass impact was next level. I personally think Violectric is a great all rounder.

This is my amateur description of what I experienced.

Won’t list source as I used quite a few.

Thanks again to everyone for their suggestions.
I wouldn't form an absolute opinion about those tube amps, without tube rolling them. I bet one could get that HA2 SF slamming like an SS with the right tubes.
 
Mar 17, 2023 at 9:22 AM Post #1,304 of 3,357
I wouldn't form an absolute opinion about those tube amps, without tube rolling them. I bet one could get that HA2 SF slamming like an SS with the right tubes.
100% agree and I'm pretty sure it will like with other tube amps...I will keep adding and rotating headphones and I think the solid state amp in my case will suit me better long term. Everyone's preference will be different.
 
Mar 17, 2023 at 11:16 AM Post #1,305 of 3,357
Hi All quick update from my end. Took day off to visit my local retailers to demo few solid states and some tube amps.

I’m no audiophile and possibly won’t be able to express properly interms of what I’m exactly hearing but in summary tried the following.

Burson Soloist 3X GT- very clean detailed widest soundstage

IFI can Pro Signature- sounds closer to tube amp warm tilt. Solid state setting was the best in my opinion. Vocals are upfront on this compared to rest of the music elements.

Auris HA2 SF -warm and natural good detail bass qty is good but not impactful like SS

Auris Nirvana expensive does everything well much much better than HA2 SF as the price suggests.

Violectric V550 did a/b a lot and this was the sound I was after. Well balanced good amount of detail while never sounding clinical or harsh. Vocals sounded amazing and instrument separation very comparable to Burson. Plus hearing so much about tube rolling,costs and availability made me think twice in investing in tube amps. Also to me ZMF Atruims sounded the best with V550 and bass impact was next level. I personally think Violectric is a great all rounder.

This is my amateur description of what I experienced.

Won’t list source as I used quite a few.

Thanks again to everyone for their suggestions.
Also curious what headphone did you use? That's an important data point I think. Regardless that kind of demo can be a lot of fun, though (potentially) mentally exhausting.

Thanks for the update.
 

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