6SN7 Tube Recs

audiocr381ve

Can you guys recommend some tubes to try in my Dodd Reference Level Pre?

I really love the 12AU7 Amperex Bugle Boys I threw in my Rogue Perseus so I'm hoping to find something with a similar sound in the form of a 6SN7.

voltz

In my MC-100b I put some New production Tung-Sol 6SN7GTB's from Tube depot and now it looks like the just have some GT's for $20 I think I gave $25 for the GTB and I liked them just fine and I am sure they are the same Marvin uses in his MC100B also. never tried any others though.

https://www.tubedepot.com/t/tubes/preamp-tubes/6sn7

Should PM Snow to see what he can get for ya!

txcoastal1

My favs are the RCA VT231 gray glass

mhardy6647

I use these and like them -- I cannot say they sound better than anything else (I don't think I've encountered a bad-sounding US-made vintage 6SN7) -- but they look very... purposeful (and I like that).

Westies closeup by Mark Hardy, on Flickr

GlennDog

audiocr381ve wrote: »

Can you guys recommend some tubes to try in my Dodd Reference Level Pre?

I really love the 12AU7 Amperex Bugle Boys I threw in my Rogue Perseus so I'm hoping to find something with a similar sound in the form of a 6SN7.

FYI
I've scored some nice tubes from Andy at Vintage Tube Services
He is a valued asset (NO affil)
He is a great resource for all things Toob! He's honest and won't steer you wrong, IMHO

(616) 545-3467

george daniel

I like the brown base sylvanias

marvda1

http://app.audiogon.com/listings/tubes-sylvania-rca-ken-rad-6sl7-gt-nos-platinum-matched-quad-2015-07-06-accessories-07109-belleville-nj

GlennDog

marvda1 wrote: »

http://app.audiogon.com/listings/tubes-sylvania-rca-ken-rad-6sl7-gt-nos-platinum-matched-quad-2015-07-06-accessories-07109-belleville-nj

Those are advertised as 6SLs . . . NOT like the OP was look'n for 6 SNs . . . just say'n

marvda1

GlennDog wrote: »

marvda1 wrote: »

http://app.audiogon.com/listings/tubes-sylvania-rca-ken-rad-6sl7-gt-nos-platinum-matched-quad-2015-07-06-accessories-07109-belleville-nj

Those are advertised as 6SLs . . . NOT like the OP was look'n for 6 SNs . . . just say'n

my bad, saw what i wanted to see

heiney9

1950's Sylvania JAN CHS 6SN7WGT's (chrome Domes). 2nd choice would be the 1960's version.

H9

heiney9

mhardy6647 wrote: »

I use these and like them -- I cannot say they sound better than anything else (I don't think I've encountered a bad-sounding US-made vintage 6SN7) -- but they look very... purposeful (and I like that).

Westies closeup by Mark Hardy, on Flickr

Those are RCA manufactured 5692's. A militarized, over built, 6SN7. I use it's very similar cousin 5691 which looks identical except it's a 6SL7. Legendary "red base" tube. Among my favorites also.

[Deleted User]

just commenting here to have the eight newest comments.

pitdogg2

stay away from any "coin base" I find them gritty in the upper registers

you can also use 6BL7/6bx7 and some of those you can get high end triple mica like 5692's and they are CHEAP...er

I have bought from this guy and he is true to his word on all tubes EXCELLENT and if you ask after a few buys he will give you a 10% discount...

http://www.ebay.com/sch/m.html?_odkw=&_ssn=presence01&hash=item25a9c0f084&item=161761783940&pt=LH_DefaultDomain_0&_osacat=0&_from=R40&_trksid=p2046732.m570.l1313.TR10.TRC1.A0.H0.X6sn7.TRS1&_nkw=6sn7&_sacat=0

mhardy6647

heiney9 wrote: »

mhardy6647 wrote: »

I use these and like them -- I cannot say they sound better than anything else (I don't think I've encountered a bad-sounding US-made vintage 6SN7) -- but they look very... purposeful (and I like that).

Westies closeup by Mark Hardy, on Flickr

Those are RCA manufactured 5692's. A militarized, over built, 6SN7. I use it's very similar cousin 5691 which looks identical except it's a 6SL7. Legendary "red base" tube. Among my favorites also.

per-zackly; thanks. Definitely US made.
Found those in a cigar box in the basement, still not entirely sure of their provenance (I think probably from my father's tube stock... but not really sure why he had them either).

6SL7s sound good in that amp as well -- but of course they're a little bit "hotter" (higher amplification factor) than the 6SN7, which I don't always prefer from a sonic perspective.

george daniel

Guys,, the RCA red bases were made and I believe that they were used in the older ICBM missiles at the time,,anyhow,, a rugged tube indeed!

mhardy6647

Yup -- tubes and missiles; even better than tubes and hifi!

mhardy6647

rednedtugent wrote: »

just commenting here to have the eight newest comments.

It took me like three hours to understand what that post meant! :-P

heiney9

george daniel wrote: »

Guys,, the RCA red bases were made and I believe that they were used in the older ICBM missiles at the time,,anyhow,, a rugged tube indeed!

That's the legend, not sure how much truth there is to that. They are often confused with Bendix Aviation and the "Red Bank" division that manufactured tubes of herculean build quality. Those went into ICBM missiles and were used in other highly hostile environments and where supreme accuracy under the most intense circumstances was a must.

The 5691 and 5692 "special red" as they are called are indeed very rugged and they are highly sought after because of limited supplies. The late 50's and early 60's production are better built and more sought than the late 60's and early 70's version. RCA is believed to be the only manufacturer regardless of brand markings. Although some suggest there is a reference to the same type tube in a General Electric product manual. So perhaps GE produced some as well.

I have a pair of late 50's and a pair of early 60's (5691's). You can tell the decade by the mica spacers. Smooth vs. serrated. Although I forget which is which. If you are buying a pair make sure they mica spacers are the same on each tube. Also anything marked as 5691 or 5692 w/a black base is NOT a true 5691 or 5692 same goes for a 2 mica version. 3 mica and extra supports are also a feature. IIRC, really late production has less extra support rods. All were rated for 10,000+ hours of use. Tightly matched from the factory as well.

They sound wonderful. Maybe a tad bloated in the mid-bass, highs a tad rolled off. Nice big soundstage, wonderful warmth and presence. These characteristics are only really noticeable after listening to something like a Sylvania JAN CHS 6Sx7WGT tube. Female vocals sound fantastic.

audiocr381ve

mhardy6647 wrote: »

I use these and like them -- I cannot say they sound better than anything else (I don't think I've encountered a bad-sounding US-made vintage 6SN7) -- but they look very... purposeful (and I like that).

Westies closeup by Mark Hardy, on Flickr

I can't get over how cool those look. I'll have to hunt down a pair!

Thanks everyone. I have a lot to work with now.

Brock, we're about to be amp buddies. I have a Pass Aleph 30 Volksamp on the way

Thanks again guys

heiney9

audiocr381ve wrote: »

mhardy6647 wrote: »

I use these and like them -- I cannot say they sound better than anything else (I don't think I've encountered a bad-sounding US-made vintage 6SN7) -- but they look very... purposeful (and I like that).

Westies closeup by Mark Hardy, on Flickr

I can't get over how cool those look. I'll have to hunt down a pair!

Thanks everyone. I have a lot to work with now.

Brock, we're about to be amp buddies. I have a Pass Aleph 30 Volksamp on the way

Thanks again guys

If you need help identifying them let me know!

Cool beans on the Aleph 30. What are you driving as far as speakers? The amp gets really hot and will raise my room temp 2-3*. It always takes about an hour of warm-up to sound it's best so make sure to make allowances.

Give this one a chance because the more you listen, the more you hear how good it is.

H9

If you don't mind, PM me what you paid, just curious as I'm loosely thinking of maybe getting the new First Watt F6. Be interested to see what you paid vs. what I paid 7 years ago and what I could reasonably expect to get if I sold mine.

audiocr381ve

heiney9 wrote: »

audiocr381ve wrote: »

mhardy6647 wrote: »

I use these and like them -- I cannot say they sound better than anything else (I don't think I've encountered a bad-sounding US-made vintage 6SN7) -- but they look very... purposeful (and I like that).

Westies closeup by Mark Hardy, on Flickr

I can't get over how cool those look. I'll have to hunt down a pair!

Thanks everyone. I have a lot to work with now.

Brock, we're about to be amp buddies. I have a Pass Aleph 30 Volksamp on the way

Thanks again guys

If you need help identifying them let me know!

Cool beans on the Aleph 30. What are you driving as far as speakers? The amp gets really hot and will raise my room temp 2-3*. It always takes about an hour of warm-up to sound it's best so make sure to make allowances.

Give this one a chance because the more you listen, the more you hear how good it is.

H9

If you don't mind, PM me what you paid, just curious as I'm loosely thinking of maybe getting the new First Watt F6. Be interested to see what you paid vs. what I paid 7 years ago and what I could reasonably expect to get if I sold mine.

Sure thing!

I wanted to get my feet wet with Pass Labs before I dropped coin on the big boys but who knows, I may end up loving this one.

Msabot1

I think 6SN7's have been out of production for quite some time in this country but not saying they can't be had here...old stockpiles...I think there still in production in Russia??.......

heiney9

Yes, New Sensor makes them (New Russian) and I'm sure there are Chinese versions available.

I've heard the Tung Sol's..........nothing compared to Old Stock tubes.

mhardy6647

They (6SN7s) were used in many, many applications including even early televisions... there are plenty of vintage (good used and even NOS) 6SN7s of various flavors still floatin' around.

pitdogg2

to add to what Brock has said

"5692 types

The 5692 was designed by RCA in response to a particular problem involving radar-controlled artillery pieces. Bouts of intense vibration (while firing) were rapidly destroying 6SN7GT types in such equipment. The 5692 was designed to withstand such stress, and has extra rugged construction with features such as an extra top mica, 5 additional freestanding support posts and a low profile. The 5692 was patented in 1948 but not produced till 1951.

5692 types were advertised as a 6SN7GT substitute that had a vastly extended lifespan – 10,000hours. This outlandish claim, however, falls apart when you examine the recommended operating specifications of the 5692. The 5692’s recommended operating parameters are much lower than those of the 6SN7GT; any 6SN7GT would last far longer (maybe even 10,000hours?) when run at 5692 ratings.

There are 2 ‘general types’ of 5692s – red bases and brown bases. The red bases in particular may have their color vary from a bright cherry-red to a dark, deep red easily confused with brown.

Who actually produced 5692s in the USA is a controversial issue amongst tube lovers; here are some of the competing theories:

-All red base 5692s were made by RCA.
-All red base 5692s were actually made by GE, but for RCA (explains the high incidence of GE labeled red bases).
-All brown base 5692s were made by CBS-Hytron.
-Raytheon made a brown base 5692.
-Sylvania made a brown base 5692.
-Westinghouse made a brown base 5692.

[My opinion, based on personal experience, is that GE made red-based 5692s for RCA, and that CBS-Hytron (earlier) and Sylvania (later) made brown-based 5692s.]

There is only one known European equivalent of the 5692 type: a Swedish-made brown base version designated either 33S30A or 33S30B.

In the late 1960s, 6SN7GTBs were often relabeled as 5692s. Remember – if the construction doesn’t include the special features unique to 5692s (mentioned earlier), it isn’t a ‘real’ 5692.

(Very) rarely, 5692s have been known to be labeled as 6SN7GTBs."

^^^^^^^^^Taken from this link VVVVVVV

http://www.head-fi.org/t/209782/the-6sn7-identification-guide

heiney9

Thanks for adding even more info. Some of it I have heard and some was new to me. One thing is for sure, the exact origins remain a bit clouded as to who really manufactured them and when and if red and brown are the same.

IMO, the earlier, the better. But IMO, that holds true for most tubes, not all but most.

Enjoy the hunt

H9

george daniel

Ah,, you are all a bunch of bad boy chrome domes

heiney9

If I had to have a desert island tube that fit my one of my amps 6SL7 spot it would be a pair of mid 50's JAN CHS6SL7WGT's (Square getter - chrome dome). What an engaging tube. Puts it the 2nd or 3rd row of a musical event. The soundstage and 3-D realism is pretty much untouched by any other tube. Extremely vibrant and fast top end with transparency you don't find very often. I have 5 pairs for a rainy day.

I believe in all I've read it's cousin the 6SN7 version is just as good, if not better.

H9

Mikey081057

I can speak for the CV181Z Shuguang Treasure as a replacment for the 6sn7. Very musical if they can fit in your amp;;

doctor r

I have experimented with a few of these. Loved my red base RCA 5692s but they tend to be more earthy and rich in the midrange. They have decent extension, but the Sylvania's have that open shimmering highs along with a fairly flat response. As I said I loved my 5692s and my 5691s (for my 6SL7 applications) but eventually found the Sylvanias to do more of what I really wanted in sound. Andy at Vintage Tube Service is outstanding if you want top quality NOS or gently used tubes that have been extensivley tested (check out his website). The prices are higher but not ridiculous for what you receive.

On the other hand I have some early 1950s Sylvania GTA (pair), GTB chrome top (quad), later 1950 GTB pair (one red and one yellow print on black base) and, one Ratheon GTB pair that I plan to list for sale soon after I get them on my Hickok USM-118 Cardmatic tube tester (which may also be looking for a new home) to recheck them again as they have been in storage in my closet for the past few years. They originally tested strong and had decently matched sections, but some of the early ones are noted to be prone to becoming a little micro phonic and I do not have any way to test that aspect of thier performance presently.

mhardy6647

I have a pretty amusing deposit of old stock (pulls) 6SN7s of various flavors... I really ought to do some vertical tastings... someday.

Of course, that said "earthy and rich in the midrange" sounds like just about where I wanna be ;- )
(heck, come to think of it, it's where I am! There really aren't many better midrange reproducers than 604-series Duplex coaxes, IMO)