LampizatOr Horizon - Tube Rolling Paradise

Great write up.

Have you compared the 6384 to the EL51?
I did not try el51 at all despite the fact that I have a quad ready in my basement. Don't want to try them due to anode caps and small kids around so I avoid all tubes with that type of connection....reality bites sometimes :)
 
I did not try el51 at all despite the fact that I have a quad ready in my basement. Don't want to try them due to anode caps and small kids around so I avoid all tubes with that type of connection....reality bites sometimes :)

Well, send them out to dinner and light up those candles!

Or send me a quad of 6384s and I'll do the comparison.
 
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OK time has come to post a few sentences about two tube types I've stumbled upon in my quest to find some "new" tube types which are a)good/great performance wise b)preferably cheap(ish) c)rare.
Big big portion of game related to those two tube types I did with a help and in cooperation with @marty and I'm sure he'll chime in particularly related to the performance of the beam tetrode tube known to outside world as 6384. Most probably not many heard about this tube type but it was produced by Bendix for military purposes to withstand ultimate operational conditions and when you hold the tube in your hand you certainly feel this "sick" attention to detail in terms of engineering. Tube is relatively small in comparison to other pentodes/tetrodes but weight wise its on par maybe even with KT170. Not to write in my words I'll just copy/paste from the text I found online:

"6384 The debate often taken up in various magazines, about which 6L6 type is "best," seems a bit silly if the 6384 is compared to the available 6L6 types. Even the Tung-Sol 5881, Mullard EL37 and Genalex KT66 look like fragile and lightweight toys next to the Red Bank tube. So it's safe to say: you won't see the likes of this tube again. The base is some kind of ceramic material, and is one of the few ceramic octal bases I have ever seen. The construction is the same luxurious style as the 6094, with all-ceramic spacers and a heater block. The pinout is the same as the obscure Tung-Sol 6AR6, a very similar rube to the 5881 physically but not quite the same electrically. Still, the 6AR6 or 6384 can be easily substituted into a 6L6 socket with rewiring or an adapter, and are rated closely enough to work well, though the 6384 makes the 6AR6 look pathetic. Extreme scarcity means we had only one 6384 to test, a new-in-the-box original Red Bank. The plate rating is 750 volts at 30 watts, which is outrageous for a 6L6 type and more typical of the infamous Mullard EL37. Yet EL37s bring $200 or more on the current NOS market, while 6384s are scarce but have nearly no value. It shows how narrow-minded the gurus can be. Simply rewire your socket or use adapter and you can use this Beastatron. Tests showed that it is indeed a beast. At 300v 50 rnA, distortion was 0.77%, lower than that of a typical Tung-Sol 5881. Peak output was 9.8V, far more than most 6L6 types and even better than a KT66. I briefly put 500v 75rnA into the cube, and it continued to work without showing red spots on the plate."
Attached is also original Bendix leaflet with all data. So I managed to secure a quad of NOS ones with several spare tubes but based on the ruggedness these will live a long life. Now since I got my H as I wrote in my previous posts I've rolled decent number of top tubes in terms of double triodes and as Marty said definitely ECC32/31 is the tube which is keeper in my system. It just shines more bright above the rest of the pack. Pentodes I also wrote about and used almost exclusively KT170 which is good option but definitely not the best as El156 and Siemens f2a were above it but due to insane prices of those I don't use them and this was a main driver of a quest to find something in this ballpark performance wise but more into KT170 price wise. 6384 fits this bill perfectly except availability but OK - Marty and myself are fine (selfish this time but sometimes you need to be :) ). Also Marty still prefers his Mullard el34 xf2 which is of course super cool as there are no universal solutions for different systems and ears but he can give a nice insight into differences of these two types (i don't have el34 xf2). To me 6384 in a combo with Mullard ecc32 provides most palpable musical experience with nothing in spectrum to stand out and hurt hearing apparatus but rather being seamlessly blended together with exceptional musicality. There is vast staging but still not being overblown where you can position the musicians on the stage with pinpoint accuracy. Details are there in spades while there is also great dynamics present. But to me color of the tone and musicality is the name of the game so these reminiscent tubes of the cold war era are a keepers for me.
Coming to the last portion of the puzzle is the recti and this particular one was showcased by Marty. I do have tons of different ones but the latest and maybe sweetest addition to collection is again a tube from the same era and same producer being known under the sky with the code name 6106. I won't go into tube details as details are attached as pdf. It is again a brutal demonstration of quality in a small package and all I wrote above was produced with combo Bendix/Bendix/Mullard. I'll try U52 as per Marty advice as I have it and see where this train leads me, but for time being I'm super happy with this combo.
Few pictures as always to visually support the writing :)
I have 8!!:) :) they, are a great tube. So well built
 

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Plate variants of the bendix 6384. The earlier variants are non carbonised tips on all 4 plate flanges. This is the better sounding one
 

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The Aries Cerat Gear is not fully balanced, Why not try the RCA connection instead? and use jumper pins on the M60 monos. I would imagine the XLR outputs on the Aries Cerat Pre-amp will not sound as good as the RCA.

If im not mistaken, you should have jumper pins connected to pin 1 and 3 on the Amplifier XLR input. Once this is done. Then proceed over to using RCA to avoid any grounding issues.

Raise or lower the Gain settings on the Aries Cerat.

RCA would be an ideal way to connect the Aries Cerat Gear to my understanding, Stavros does not make his pre-amps fully balanced and from his website, almost everything seems single-ended.

I have the fully loaded MP-1 3.3 and have used it on various amps. Its not always sounded its best and system matching is crucial on gain. Impedance matching would be another issue apart from gain matching.

The MP-1 would not always sound good on Single ended systems as compared to balanced so again its crucial you work with the gear and try various settings and methods. It all depends on system matching.

You would ideally also have single-ended amps on site so you can switch out amps whilst comparing both pre-amps.
 
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Can anyone help me? I read that black base Mullard are probably fake. How is it possible to find out which one is real or fake. I found these Mullards:
Are they worth to buy? Thank you
 
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Is this possible? I have had my Horizon for over two months and chose not to do any tube rolling until I fully grasped the Horizon sound. Today, I changed the Rectifier from the original KR 5U4G to Sophia Electric Aqua 274B. The results were stunningly better. I thought the rectifier represented about 10% of the total sound quality. I may be wrong. But for a $199 tube what a difference in MY system.
 
Is this possible? I have had my Horizon for over two months and chose not to do any tube rolling until I fully grasped the Horizon sound. Today, I changed the Rectifier from the original KR 5U4G to Sophia Electric Aqua 274B. The results were stunningly better. I thought the rectifier represented about 10% of the total sound quality. I may be wrong. But for a $199 tube what a difference in MY system.
I had the same epiphany Will. I was stunned to see how much difference a rectifier could produce in the sound.
 
Can anyone help me? I read that black base Mullard are probably fake. How is it possible to find out which one is real or fake. I found these Mullards:
Are they worth to buy? Thank you
The issue with the black base Mullards are specific to certain tubes. I've been in communication recently with a gentleman that worked at Mullard for decades and he assures me that Mullard did indeed make certain tubes with black bases at several of their plants. The black base issue that is most popularized is mostly a concern with EL34's made in Blackburn, which typically have a brown miconol base with embedded golden flakes.
According to Pasquale Russo, who has written the definitive document on the EL34, there was a black based EL34 XF2 w a single getter than had a black base made in Blackburn from 71-73, as well as some later XF3 and XF4's that were made in Blackburn with a black base. But all double getter EL34's had brown (or dark brown) bases.

I'm familiar with the particular pair of ECC32's you describe as I purchased an identical pair from the same source. JF is the date code (June, 1954). They are authentic and superb and probably made in Blackburn although no definitive marking either etched or printed on the glass can be found other than the date code. Not inexpensive, but tubes in this condition are uncommon and therefore costly.
 
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Brief follow-up...The Audioantiquary ad says the tubes were manufactured in May 1968, but if you look carefully, it says they were tested in May 1968. My Mullard source believes the date code "JF" signifies they were actually made in June 1954.
 
Brief follow-up...The Audioantiquary ad says the tubes were manufactured in May 1968, but if you look carefully, it says they were tested in May 1968. My Mullard source believes the date code "JF" signifies they were actually made in June 1954.
Even better?
 
The issue with the black base Mullards are specific to certain tubes. I've been in communication recently with a gentleman that worked at Mullard for decades and he assures me that Mullard did indeed make certain tubes with black bases at several of their plants. The black base issue that is most popularized is mostly a concern with EL34's made in Blackburn, which typically have a brown miconol base with embedded golden flakes.
According to Pasquale Russo, who has written the definitive document on the EL34, there was a black based EL34 XF2 w a single getter than had a black base made in Blackburn from 71-73, as well as some later XF3 and XF4's that were made in Blackburn with a black base. But all double getter EL34's had brown (or dark brown) bases.

I'm familiar with the particular pair of ECC32's you describe as I purchased an identical pair from the same source. JF is the date code (June, 1954). They are authentic and superb and probably made in Blackburn although no definitive marking either etched or printed on the glass can be found other than the date code. Not inexpensive, but tubes in this condition are uncommon and therefore costly.
Really good post.

As humans I just think we are so good at losing the best things that happened in the past.

If we don't know where we are, and have been, we don't know where we are going.
 
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I would not waste money on a Horizon exploring that fact, though.

And it would be a waste of money better spent on other aspects of life IMHO.
 
Did not appreciate how fun this can be before upgrading to the Horizon.
After a few component switches... revisiting all the tubes.... still feels like there are many to try based on this thread and tube connoisseur back channels...

1674186860637.jpeg

1674186883846.jpeg
 
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Wow! Excited to see what you choose. I asked this on Horizon thread, but maybe better here:
For those using the Tungsol 6SN7 drivers and/or tube experts. Are the Hyvac branded ones the exact same tube?
 
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Did not appreciate how fun this can be before upgrading to the Horizon.
After a few component switches... revisiting all the tubes.... still feels like there are many to try based on this thread and tube connoisseur back channels...

View attachment 103211

View attachment 103212
Jeez, I thought I took on some considerable tube rolling projects, but compared to this...I am not worthy!!
 
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