ZMF Aegis Official Thread

[Wes S]

Nice! I wonder how their detail and resolution compares to the EL50 red base solid plates.

I don't have any EL50 solid plates, but I can already tell you the resolution and detail is very impressive and easily hangs with (actually just might best?) my EL50 Mesh Plates and all other tubes. I need more time to compare, but having already heard little nuances I have not noticed before, I can confidently say they have a high level of detail and resolve.

More to come. . .

 

[OctavianH]

Nice! I wonder how their detail and resolution compares to the EL50 red base solid plates.

In my view the level of detail and separation is below EL50 red base solid plates, but not very far. EL51 is more musical, a different signature. If you would ask me, red base solid plates are my favourites, above EL51. But the EL51 sound is addicting and warmer. Warmer, less precise. I will wait to see what others think about these.

 

[Wes S]

In my view the level of detail and separation is below EL50 red base solid plates, but not very far. EL51 is more musical, a different signature. If you would ask me, red base solid plates are my favourites, above EL51. But the EL51 sound is addicting and warmer. Warmer, less precise. I will wait to see what others think about these.

Curious, which version of EL51 are you using? I am using a pair of Philips from 40’s with dual Trough/Inverted Pan Getters, of which I assume is the earliest version.

 

[OctavianH]

Curious, which version of EL51 are you using? I am using a pair of Philips from 40’s with dual Trough/Inverted Pan Getters, of which I assume is the earliest version.

Mine is a newer version:

Date codes on it are M83/◿8G. Your's has also Herleen codes?

 

[Wes S]

Mine is a newer version:



Date codes on it are M83/◿8G. Your's has also Herleen codes?

Got ya. Mine are a bit different, and I am not quite sure where they are made.

 

[OctavianH]

Got ya. Mine are a bit different, and I am not quite sure where they are made.

Both our pairs have new Philips date code, 3 digit, which as far as I know was changed in '61 to 4 digit (adding week of manufacture at the end). The Philips "old code" was replaced from what I have read around '55. So I guess both our tubes are made in different factories, sometimes in 1958/1959? Yours have 2 as change code while mine have 3. M8 = EL51, is the tube type.

I have no clue what is "K" factory code. I asked ChatGPT and he says Mullard Mitcham, which I am unsure if it is correct. According to the Philips code book, R = Mullard, Mitcham.

If you find out more about "K" let me know. And do not believe ChatGPT, I guess here it is wrong.

 

[Hickory Deadglove]

Both our pairs have new Philips date code, 3 digit, which as far as I know was changed in '61 to 4 digit (adding week of manufacture at the end). The Philips "old code" was replaced from what I have read around '55. So I guess both our tubes are made in different factories, sometimes in 1958/1959? Yours have 2 as change code while mine have 3. M8 = EL51, is the tube type.

I have no clue what is "K" factory code. I asked ChatGPT and he says Mullard Mitcham, which I am unsure if it is correct. According to the Philips code book, R = Mullard, Mitcham.



If you find out more about "K" let me know. And do not believe ChatGPT, I guess here it is wrong.

By using old fashion search tool, i find that K is a unknown factory and R is Mullard, Mitcham.

https://www.audiotubes.com/mullcode.htm
https://fr.scribd.com/document/697847164/PhilipsCodeListAB-v8

I read yesterday an article that say that AI can have hallucinations (that is the technical term) because it get too much informations and the engineers don't know why.

 

[Toonartist]

The Philips date codes can be found here. You should be able to decode it from that.

GEC used to use cap letters as a date code as well, from memory K = 1954. Just in case they had a hand in the manufacture and it's a rebrand

Edit. I think the M8 is the tube type followed by version number i.e. 2/3. The doc confirms M* as being EL51. (M82 or M83). Both K & M as a starter letter are marked as ? so not sure where they were made.... if that table is complete/accurate.

 

[DJ XtAzY]

Finally the Brimar 5R4GY w/ OO Getter arrived, along with the replacement EL38 (mentioned about the broken getter a few threads back). Although this time they sent me a EL38 with a double rectangular stacked getters. So now I have mismatched pairs, where my other one has a trough getter. They both have code 1326, but i guess they were created on a different dates (2E3 vs 2I0). Hopefully they won't sound that drastically different, even though you guys mentioned it's best they're the same type. Still waiting for my adapters, which will arrive tomorrow.

 

[Isaacc7]

Finally the Brimar 5R4GY w/ OO Getter arrived, along with the replacement EL38 (mentioned about the broken getter a few threads back). Although this time they sent me a EL38 with a double rectangular stacked getters. So now I have mismatched pairs, where my other one has a trough getter. They both have code 1326, but i guess they were created on a different dates (2E3 vs 2I0). Hopefully they won't sound that drastically different, even though you guys mentioned it's best they're the same type. Still waiting for my adapters, which will arrive tomorrow.

Don’t sweat it. All of the el38 are pretty close as it is. Whatever difference there is will be easily compensated for by your brain. I’ve always thought it was a bit silly to pursue absolute precision with tube amps. Engineers scoff at single ended tube amplifiers’ ability to reproduce anything accurately. I say lean into it and just enjoy the sounds you get.

 

[SunRa Fan]

The Telefunken KT88. According to their marketing, they're extensively burned in but out of the box this pair had somewhat muted highs. After a couple of days of burn in the highs did develop enough to make for decent listening on the Caldera. Overall, it has a refined, smooth character with good detail retrieval, decent sound staging and a dark background. Kind of a more affordable Ray Reserve KT88. It just doesn't offer that last bit of air and resolution like the Ray Select KT88 does, so it's better on the Atrium. A good but not great tube, especially considering the price premium. The Gold Lion KT88 is a much better choice.

 

[ckhirnigs113]

After much deliberation, I’ve decided to sell my GEC U52. I’m perfectly content with my RCA rectifiers from the 40’s, so I feel silly keeping such an expensive tube. I wanted to let you guys have first shot at it before I list it in the classifieds this weekend. Just let me know if you’re interested.

 

[theveterans]

My input tube rolling journey isn't over yet

Tubes haven't arrived yet, but it's not NOS, but new production just to test the waters

Hint: it's not in the 12xx7 family

Will post some impressions with Bokeh Open after tubes arrive

 

[David A Silva]

RCA 5R4GY, SYLVANIA JAN CHS 6SLGT, TUNGSOL KT170…

It’s been a couple of days with these tubes in the saddle and I’ve put about 30 hours on them. I’m comparing the KT170 to my notes on the RCA 6550 in my McChanson. I’ll double check my impressions in the Aegis when I can find the 6550s in the pile of tubes in my cabinet… The KT170s are more neutral in the mid bass and mids, a little heavier in the deep bass and upper treble. The treble almost has a sheen to it. Staging is bolder, and imaging is deeper and wider but less focused. I feel like I’m on stage in the middle of everything.

Different enough from the 6550 to have in my collection. For me it excels in more intimate ballads and jazz, like holding a magnifying glass to the music.

 

[Deleeh]

RCA 5R4GY, SYLVANIA JAN CHS 6SLGT, TUNGSOL KT170…

It’s been a couple of days with these tubes in the saddle and I’ve put about 30 hours on them. I’m comparing the KT170 to my notes on the RCA 6550 in my McChanson. I’ll double check my impressions in the Aegis when I can find the 6550s in the pile of tubes in my cabinet… The KT170s are more neutral in the mid bass and mids, a little heavier in the deep bass and upper treble. The treble almost has a sheen to it. Staging is bolder, and imaging is deeper and wider but less focused. I feel like I’m on stage in the middle of everything.

Different enough from the 6550 to have in my collection. For me it excels in more intimate ballads and jazz, like holding a magnifying glass to the music.

What do you think of Mcchanson vs Aegis?
Both on the same level or both on the same level only that Mcchanson does certain things better than Aegis and vice versa?
So what one amplifier can do, the other does slightly better or less well.
I can imagine that the two are pretty close to each other.
Perhaps Mcchanson is a nose ahead, depending on the design with the caps, transformer, 200/240v switch and more choice in the driver section.