Darkvoice 336i & 336SE Tuberolling PartII
Oct 4, 2019 at 9:30 AM Post #2,479 of 14,501
I've had pretty good hifi in the past marantz cd17 ki signature , sonus faber musica amplifier and a rebuilt pair of Quad esl 57s , a,so had jamo concert 8 so i like solid bass christal clear mids and a sparkling top end with cymbals , if possible .I use hd650 headphones I might have to rethink them as they are now bass heavy and verry dark sounding ,regards taffy
 
Oct 4, 2019 at 9:39 AM Post #2,480 of 14,501
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Brimar is pretty good, I have one with clear glass instead of black glass...GEC is even better... actually all British valves are very expensive
I just bagged 1 from the uk NOS £70 including postage made in 1960 I think I did well
 
Oct 4, 2019 at 1:55 PM Post #2,482 of 14,501
HD650 is considered a dark headphone, but OTL amps can help to reduce its darkness.

It is a warm and non-fatiguing headphone, good for long listening sessions, and it's forgiving to bad/harsh recordings.

It's always a pleasure to listen to my HD650. Definitely a keeper. Many audiophiles keep one in their stashs.
 
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Oct 4, 2019 at 1:57 PM Post #2,483 of 14,501
Ok thanks , I have to start somewhere sooo I listened to all the comments and advice from you guys , I'm pretty sure I can try it out and resel it easily for what I paid for it ( you saved me a lot of time and money ) thanks again all my ducks in a row now I've just bought a used power cable supra sheilded for £13.00 delivered ,I'm retired " I'll health " I have plenty of time to look for good deals
 
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Oct 5, 2019 at 7:08 AM Post #2,485 of 14,501
Hi ,guy just to let you know some information I ordered a NOS Brimar 6SN7GT From VALVE TUBE GUITAR GUITAR AMPS in Scarborough for £70.00 (scruffy box) at 15.40 Yesterday it arrived am this morning WOW That's Boody service, I'm just waiting until next Wednesday until my Darkvoice 336se arrives lol
I have no ties or do not know anyone at that company
 
Oct 5, 2019 at 2:08 PM Post #2,486 of 14,501
Hi ,guy just to let you know some information I ordered a NOS Brimar 6SN7GT From VALVE TUBE GUITAR GUITAR AMPS in Scarborough for £70.00 (scruffy box) at 15.40 Yesterday it arrived am this morning WOW That's Boody service, I'm just waiting until next Wednesday until my Darkvoice 336se arrives lol
I have no ties or do not know anyone at that company
You scored!! Nice tube!! Your gonna be in audio NIRVANA!!
 
Oct 5, 2019 at 2:16 PM Post #2,487 of 14,501
7N7-CF8G-6CG7 Lets Do This...

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So I've been wanting to do this rolling session for awhile and with my little knowledge on adapters it took some time to get these all together for this comparison write up. Before we get knee deep into this I decided to exclude the 12AT7 as it has no breath of air to be considered for this roll up... it's gonna be super hard for me to express in adjectives on the remaining three tube types, The 7N7, CF8G , and 6CG7. All of these exude that open airiness, So lets begin this tough task....

(Before I begin you need to know one size does not fit all as far as adapters go...get the adapters now..even if your just thinking of buying one of these tubes...just get them).

Headphones - Senheiser HD6XX & Fidelio X2

Tidal Playlist (Miles Davis-Radiohead-Bob Marley)

https://tidal.com/browse/playlist/b5ea485b-fdff-440a-944c-ca4ecca5f977

Tung Sol 7236 used for the push duties

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Marconi 6CG7 1950's

History:

"In 1954, RCA came out with the 6CG7, which was pitched as a direct equivalent of the 6SN7GT. Although audiophiles found that the 6SN7GT typically sounded better, this was the beginning of the end for widespread usage of the 6SN7GT. The 6CG7 was unique in having a shield between the two sections". - effectrode.com

The 6CG7 caught my attention going through the Darkvoice Massdrop Forums, especially this post from user LIBY555

"Personally, I liked to use another different tube socket adapter and use a 6CG7. The 6CG7 has been called a 6SN7 in a 9 pin bottle. Electrically they are very, very similar but the 6CG7 does not sound like a 6SN7. The 6CG7 is brighter and faster sounding. Most of the 6CG7's are brighter sounding tubes, again, except for the RCA . You will find Sylvania, GE, Raytheon and even the occasional Tung Sol gray plate 6CG7. Depending on your ears all of them may be good for you. The RCA 6CG7 later became 6FQ7 and either will work ok but the RCA is richer sounding than the other 6CG7's but still brighter than most 6SN7's. I liked the 6CG7's a lot better most of the time.
The investment in a 6CG7 and adapter is much less than any good NOS 6SN7". - LIBY555

I grabbed a set of the RCA tubes for a side comparison to the Marconi, and yes as user LIBY555 described it the RCA sound fuller but I suspect only because the highs are not as extended as the Marconi, the RCA are without the shield between the plates so not sure how that effects sound just a note in build. These tubes do rival the nicer 6SN7GT out there and if on a budget, worth the collection.

(Kind Of Blue) Instruments are really life like here, I got front rows seats, no I'm sitting in the middle of this jam session. The double bass instrument just bellows beautifully. Smoked filled bar sipping on a beer kinda mood.


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7N7 1950's (Philco, Sylvania)

History:

"Sylvania and Raytheon came out with a loctal version, called the 7N7, which, interestingly, was registered in 1940, well before the 6SN7GT. Primarily due to the non-acceptance by RCA (the Microsoft of its time), the loctal line, though technically superior to the octal types, withered away in the late 1940s". - Effectrode.com

They do make a strong case for sounding technically superior. These tubes can exude mad air of sound around you (especailly with the Fedelio X2), a very lively tube. And when you find a great jazz recording like Kind Of Blue by Miles Davis.... does it get any better?

The 7N7 is basically a 6SN7GT tube without the base, all the internals are the same (especailly/mostly with the short bottles). I don't see much or have yet to see a tall bottle 6SN7GT bottle that shares the same innards as the tall 7N7. The other differences would be the pin layout.

For the most part of the three 7N7 tubes I have (one short, two tall bottles) the tall bottles have the better imaging and overall stage presence. I do have to mention Headphoneus Supremus member bcowen has named a particular 7N7 tube, one that he states..

" I ran across an Ebay ad for the tall bottle pictured below. And the rest is now history. Powerful bass, dynamic and punchy, a midrange that's *just* right, beautiful treble, the rhythmic drive of a Foton. But there are two things that are remarkable with this tube: imaging (or maybe soundstaging) that locates each performer or instrument in its own acoustic space. You can pick out the individual voice in a chorus and the 3rd violin from center in an orchestra. And you hear the space surrounding them. I haven't heard this space-reality thing with headphones before". -bcowen

He's named this tall 7N7 tube "The FRANKENTUBE" and it's caught on by all headfi members following this guy. The one tube that will for sure qualify as The FRANKENTUBE is the JAN CBRZ 7N7 (Lansdale). These are super rare and hard to find. He does point out there are carbon copy builds with no notable differences in sound. (General Electric for example) again more from bcowen..

"The stuff required to be knighted as a Frankentube:

1) Tall bottle with unique 'squared-off' top shape.
2) Top getter with flashing that completely covers the inside of the bottle at least a 3rd of the way down, and usually half way down.
3) T-Plates where the flat part of the plates face each other. There are gray plate and black plate versions. I have both, and can't honestly tell much difference between them.
4) True racetrack mica supports, top and bottom. By that I mean that the shape is a true oval, and not like a rectangle with ends that are rounded (see below).
5) Square (or slightly rectangular) pan-type getter tray (or support)".

-bcowen

I can only imagine what a FRANKENTUBE would sound like as the tall tubes in my possession lack the very flat top tube appearance. As they are now, they sound incredible. Instrument separation above average, and lively.


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Sylvania CF8G VT-99 1940's

History:

"The immediate predecessor of the 6SN7GT was the 6F8G, developed by RCA in 1937. The 6F8G was a dual version of the 6J5, which was a slightly “hotter” version of the 6C5 of 1935. The 6F8 had the larger “G” (or ST-12) bulb with the troublesome grid cap for one of the triodes. The compact straight-sided GT “Bantam” types, introduced by Hytron in 1938, had become the rage by the early 1940s, and the 6SN7GT was the natural evolution of the unwieldy 6F8G". - effectrode.com

The Sylvania VT-99 CF8G has a lush warm sound, with sweet reverb that seems to echo off walls of a concert hall. Laid back and smooth. As what you would expect from a tube made in the 40's, an 80 year old tube..let that sink in for a minute. Of the three this one will stand out the most as an interesting conversation piece, the small coke bottle and wired top cap design, you almost want to call this your end game tube and permanently leave it there. Because of the afore mentioned qualities I can forgive it's small short comings, it's not as dynamic or as fast as the 7N7 or 6CG7, but it doesn't need to be, it's perfect as it is, romantic and musical.

Note: This tube runs the coolest of the three

Tid Bits:

Kind Of Blue (by Miles Davis) if your into this album or new to it, I highly recommend Somethin' Else by Cannonball Adderley. If there's a resemblance in style it's because Cannonball left his group to help Miles Davis on the Kind Of Blue recording (the highest selling jazz album of all time), a year later Miles Davis returned the favor and helped him record Somethin' Else. both classics.

 
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Oct 5, 2019 at 10:18 PM Post #2,489 of 14,501
7N7-CF8G-6CG7 Lets Do This...


So I've been wanting to do this rolling session for awhile and with my little knowledge on adapters it took some time to get these all together for this comparison write up. Before we get knee deep into this I decided to exclude the 12AT7 as it has no breath of air to be considered for this roll up... it's gonna be super hard for me to express in adjectives on the remaining three tube types, The 7N7, CF8G , and 6CG7. All of these exude that open airiness, So lets begin this tough task....




Fantastic write up! :thumbsup:

Always a pleasure to read articles like this.

I become interested in getting some of these adapters just to dip my toes into the neverland of new tubes :D
 
Oct 5, 2019 at 10:23 PM Post #2,490 of 14,501
Ok thank you very much , I just bagged a pair or used Sennheiser HD600 for £88.00 Delivered, WOW I couldn't believe it I'm going to be busy the next few weeks A/B comparison between my HD650s before tube rolling , thanks again all for brilliant advice ,and coments


HD600 shares a lot things with HD650, and is a more neutral sounding headphone, can be bright sometimes (vs. HD650)
 

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