Rolling Power Tubes

zingo

A new integrated amplifier rolled through my door which has the ability to roll a quad of any variant of the KT88, EL34, or 6L6 tubes. With past amps I have not had the option to roll different types of tubes, just variants within the same family, so I have moved up the tube line and usually ended with Shuguang Treasures. This amp however, I am focusing on rolling the different kinds of tubes as that will provide me with a variety of listening and aural experiences as each type of tube has a different design, and thus sound. I'm sure at some point I will be honing in on what type of tube sounds good with that system and focus from there, but right now I'm having fun just rolling different types, even if they aren't premium.

I started with Shuguang standard KT88s and EL34s. Obviously these are very different sounding tubes, and I found the KT88 very linear, and almost a little too un-colored and flat. The EL34 on the other hand was very nice sounding, but had a few unnatural bumps that made it sound very musical, but just off in a few places. Last night I popped in a quad of SED =C= 6L6GC tubes and will be giving a listen this weekend. Even though rolling variants is fun, being able to roll different tube types is even better! The last thing I need right now is a piece of equipment taking up more time and money...

PS. The pre-section uses stock 6N1 tubes, but also accepts any variant including 6N1P; which should be on my door step today. :biggrin:

heiney9

60's-70's Russian 6N1P's are pretty darn good. I bought a lot of 1960's Russian military 6N1P tubes a few years ago, but I've slowly sold off all but a couple pair that I still roll once in awhile. The most excellent ECC85/6AQ8 can be subbed for 6N1 and 6N1P's and they are superior to the Russian 6N1P's. My favorite 6AQ8 is either the Telefunken or early Valvo Hamburg "D" getters with the solid cross bar...........very hard to find and a bit pricey but worth it.

By far the best 6L6 is the early RCA with the gray glass.........superb and exepensive.

Overall, I've found signal tubes have a more dramatic influence on the sound of an amp than the power tubes, unless you are rolling a NOS Mullard for an inexpensive JJ, etc.

H9

P.s. The chinese 6n1's are horrible

heiney9

Jake, you need to start swapping in some older tubes. I only see you post about current production stuff. Get a pair of Telefunken of Valvo 6AQ8's in place of the 6N1's. Not a lot of manufacturer's actually produced 6AQ8/ECC85's so you find a plethora of re-labels so beware. If you actually go down that path I can help. I have a pair of just about every variant of the 6AQ8 that was produced.

Munich; Ulm; East Germany; Blackburn; Heerlen; Hamburg; France; USA; Russian; China.

michaeljhsda2

heiney9 wrote: »

The most excellent ECC85/6AQ8 can be subbed for 6N1 and 6N1P's and they are superior to the Russian 6N1P's

:cool: I didn't know this. I think I have at least 1 Siemens ECC85 (labelled Harmon Kardon) that I'm gonna roll in my integrated amp. I'll have to check my small cache of tubes to see how many I have. I currently have the Russian military 6N1P tubes in it now.

zingo

I realize that the specific tubes I'm rolling aren't the best, but the exercise for me right now is more in rolling different types than variants. Thanks for the suggestion on the 6QA8 as I didn't realized that could be swapped. Even if the 6N1P I ordered are not the best option for the tube, they are electrically different than the 6N1 they are replacing, and that's what I wanted to listen for.

michaeljhsda2

Brock,
Are you sure that ECC85/6QA8 is a substitute for the 6n1? I found the following post on the AK forum (hope that's ok to quote it) "the ECC85/6AQ8 has a gain of 57 and a transconductance of around 5500 umhos... the 6N1 has a gain of around 35 and a transconductance of around 4500 umhos. The gain difference will change the circuit operation...This so called "compatibility" has been bandied about for years... in reality, there IS NO real 1:1 equivalent to the 6N1."

heiney9

The problem is many of the Chinese sites state the 6N1 and 6DJ8 are compatible and they are not.

In all my research and usage I have used the 6AQ8 in place of Chinese 6N1's for a couple years with excellent results.

The Dared MP5 clone I have uses Chinese 6N1 as driver tubes. I have used Russian 6N1P and 6AQ8/ECC85. In fact the owners manual for the Dared clone states an ECC85/6AQ8 can be used in place of the 6N1.

I did a alot of research when I bought the Dared clone and this works. Now if you don't believe me or are worried you can contact your manufacturer. One thing I will say is NEVER use a 6DJ8 in place of a 6N1 or 6N1P or visa versa.

You are correct there is no 1:1, but the difference is minimal. Of course I only listened to the Chinese 6N1's once so perhaps they have more gain. I just know the TFK and Valvo ECC85 sound superb.

H9

P.s. The American market Dared MP5 uses 12AX7's instead of 6N1's. It has a different resistor value.

drselect

Jake,
George suggested I check out some 6P3SE for the amp that I got from you so I picked up a quad. I currently prefer them to the EH 6CA7 or the Shuguang that came with the amp.

zingo

I can't seem to find 6P3SE anywhere... Got a link?

The manual for the amp claims signal tube options include but are not limited to 6N1, 6DJ8, 6922, ECC88, 7308 and 6N1P. You think the 6AQ8/ECC85 will work Brock?

heiney9

Best check with the manufacturer. I use them in place of 6N1's and they are recommended in my manual. I have been told and read the 6N1 and 6DJ8 and family are not compatible, perhaps yours is wired differently.

drselect

zingo wrote: »

I can't seem to find 6P3SE anywhere... Got a link?

Got them from Jim Mcshane.
They are about 1/4 or less down on the list.

http://www.mcshanedesign.net/tubes.htm

michaeljhsda2

drselect wrote: »

Jake,
George suggested I check out some 6P3SE for the amp that I got from you so I picked up a quad. I currently prefer them to the EH 6CA7 or the Shuguang that came with the amp.

Are the Shuguang's the EL34-B's?

drselect

michaeljhsda2 wrote: »

Are the Shuguang's the EL34-B's?

No. They have EL34A printed on them.

michaeljhsda2

Ok, thanks anyway. I'm looking for the EL34-B's.

thsmith

WIng C EL34s worked well in my Athem. I agree with H9 on power tubes not being a dramatic as signal tubes, in most places but the Anthem responded very well with power tubes.

If you could get your hands on some treasure KT88s you might be surpised.

heiney9

Don't get me wrong I have tried Original Tesla EL34's, JJ EL34's, Late Tesla E34L, EH EL34's, JJ Blue glass EL34's and they all sounded different but not as much difference between those as I notice with pre/driver tubes. Those *can* have a dramatic swing in sound.

H9

zingo

I've rolled many Treasure tubes through many amps, and they are fantastic tubes. I'm sure I'll head that way in the future once I've felt out all the different power tubes.

zingo

Anyone rolled the new Gold Lion KT77 or KT66? I know they have been mentioned a few times on here a few years ago, but anyone recently?

I know you recommend NOS tubes Brock, but I've had good success with new Gold Lion and Shuguang Treasure, and it's easy to buy new tubes because you don't have to hunt for availability, condition, etc.

heiney9

zingo wrote: »

Anyone rolled the new Gold Lion KT77 or KT66? I know they have been mentioned a few times on here a few years ago, but anyone recently?

I know you recommend NOS tubes Brock, but I've had good success with new Gold Lion and Shuguang Treasure, and it's easy to buy new tubes because you don't have to hunt for availability, condition, etc.

I understand about availability and condition, but I will say I've never had a condition or availability issue other than having to wait for more rare tubes to come up for sale.

For me, buying Treasures or Gold Lions is really about cost first and then not trusting the longevity and consistency. For what places are charging for these premium current stock tubes I can buy almost 2:1 old stock used tubes, unless you are talking the really premium tubes. Even then I've paid ridiculously cheap prices for even "holy grail" tubes, by waitung and being selective.

I also think the big difference for me is some of the tubes I use aren't the most popular designations so I can buy them used a lot cheaper. Although I have a pair of Valvo ECC83/12AX7's from the 50's with the slant getter (very desirable) and I paid less for those than I would have for a new pair of Treasures. So you can see my dilema because the Valvo slant getter from the 50's is one of the best sounding 12AX7's out there and the quality of the tube is superb.

I would like to try some of these well reviewed new tubes, but frankly the cost is enough of a deterent because I can buy premium Old Stock tubes for the same amount or less. The wild card(s) are availability and condition and I've had no problems w/either. I will admit a large part of the fun is the research and the hunt for older tubes. I have so many more tubes than I could ever listen to in a life time.

Now that New SED Winged "C" have jumped way up in price I may try the Gold Lion KT77 in place of my EL34's.

Outside of the Treasures and Gold Lion, I have tried several New tubes and none of them have come close to stuff from the 50's and 60's so that makes me a little uneasy as well.

Just a little insight into my thoughts on the subject.

H9

doctor r

I have used the New Svetlana EL34s, Old Svetlana EL34 (Winged "C"), Tung Sol EL34B, RTC EL34, New Winged "C"s and Gold Lion KT77s. The Gold Lion KT77s had excellent presence with good extension at both end of the spectrum, but their sound stage was flat. After all my power tube rolling for the EL34 I kept returning to the Winged "C" EL34s. They provided the best 3D sound stage with excellent mid-range and very open airy highs. Again the KT77s were very nice, but more in your face without the open sound stage I was looking for IMO.

heiney9

I agree Dr. R the Winged "C" are just so balanced and have a great, open soundstage. I haven't put enough time or done a really controlled comparison to some original Tesla's I have. Do you notice any differences between the original Svetlana Winged "C" and the SED Winged "C"?

The reason I ask is I have a chance to buy some original Svetlana Winged "C" but they are a bit pricey and if there isn't any difference I'd like to save my $$$.

doctor r

My Shanling Amps came with original Svetlana (winged C) tubes. They sounded excellent but after a year I started rolling the other EL34s. My first aquisition was Svetlana tubes made by the New Sensor corp. I thought I had lost my mind (and sound) (or was that sound mind, I don't know) until I started doing my research. The new Svetalna tubes did not perform well in my system. I eventually aquired another used quad of original Svetlana SED EL34s and a new quad of Winged "C" from Jim McShane. I changed them around a few times and found no real difference. They bested all the other new production (New Sensor) brands and types in my system. I have since upgraded to a KT88 based amp and will be selling the EL34 based mono blocks.

zingo

heiney9 wrote: »

Outside of the Treasures and Gold Lion, I have tried several New tubes and none of them have come close to stuff from the 50's and 60's so that makes me a little uneasy as well.

What would you suggest for me then for NOS tubes that are currently available to purchase? Amp can use a quad of KT88, EL34, or 6L6 variants as output, and a quad of 6922 variants as input. I like EL34 variants as I think they have a very musical sound, but I'm open to any tubes that sound good. :biggrin:

heiney9

Jake,

If you looking for actual New (as in new in box and never used) Old Stock in an EL34 you might have to take out a 2nd mortgage. All my EL34 tubes with the exception of the Siemens were bought used. I paid a lot for the Siemens considering I use them in a secondary rig and the little Norh SE-9 integrated cost so little, I now have more in tubes for it than the unit cost by almost 3 times. For the main rig I don't tend to put cost limits on myself, but for the office rig I just can spent $300-400 for a pair of NOS Mullards

So here are my recommendations

There is no better 6L6 than the 50-60's RCA gray glass 6L6, they are a bit pricey and new will cost a lot. Buttery smooth midrange, great upper end and real solid meaty bass. The nice thing is IIRC, these were one of the most popular tubes made so they should be plentiful so if you are patient you can find a good deal.

For EL34's I like 3:

Original 70's and 80's Tesla are very nice, the older ones are pricier than the later ones. There is a whole tutorial on the net about how to date them.

SED Winged "C" EL34 are really nice, well balanced, nice airy top end and great midrange and used to be a great bargain. In the past 6 months they have increased in price about 30-35%.

Siemens E34L - Siemens never made their own EL34 early Siemens were relabeled Telefunkens and later relabled RFT's you can tell because they have crimped plates rather than welded plates.

The Siemens in the link is a very late Tesla manufactured E34L right around the time JJ/Tesla started making tubes. It's a great sounding tube w/ more bottom end than the Winged "C" but still maintains the airy top end and very good midrange. This is the seller I bought them from and he is soild and these are NOS in Siemens boxes. I had to do a LOT of my owne research to figure out the origin of these tubes.

http://www.ebay.com/itm/260763693094?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Problem is these have gone up because of the fluxuation of the GBP/$$. I paid about $87/pr about 9 months ago.

As far as the 6922, I'm not that familiar but my brother's Dodd ELP used them and I did a little research for him and the Amperex Bugle Boy "A" frames get high marks.

H9

michaeljhsda2

H9,
Are these similar to the ones you linked to? Seems like a good price. http://www.ebay.com/itm/TESLA-EL34-6CA7-MATCHED-QUAD-OO-GETTER-/110730866959?pt=Vintage_Electronics_R2&hash=item19c812f10f#ht_928wt_1272

heiney9

michaeljhsda2 wrote: »

H9,
Are these similar to the ones you linked to? Seems like a good price. http://www.ebay.com/itm/TESLA-EL34-6CA7-MATCHED-QUAD-OO-GETTER-/110730866959?pt=Vintage_Electronics_R2&hash=item19c812f10f#ht_928wt_1272

Construction wise they are a little different but those are nice Tesla tubes and yes that's a pretty good price.

Yellow label with the 33 on it means Roznov plant and think those are mid 70's.

H9

heiney9

A little secret, I use the Tubemonger Library as one of my sources for tube research. They have some really great pics of all types of tubes. It's usually the first place I start when I'm trying to identify a tube. It really helps to see the internal construction because many of the photos are fairly large and detailed.

I rarely rely totally on a sellers identification especially if they aren't a reputable dealer, so I do my own research and verifying before I buy tubes off Ebay or Audiogon, etc. 50% of the time people are wrong in some aspect about what they are selling. Not maliciously, just by making assumptions or haphazardly doing research. If I see something really wrong, even if I'm not buying, I always send the seller a nice note.

http://www.tubemongerlib.com/gallery2/main.php?g2_page=2

H9

michaeljhsda2

heiney9 wrote: »

I use the Tubemonger Library as one of my sources for tube research.

Just saved it in my favorites. Thanks!

heiney9

Here's a review of EL34's from the POV of a guitar amp, but other than the overdrive capabilites they should be the same in an audio amp. Although in my rig I don't find the E34L (Siemens) bright or forward like the review states.

Pay close attention to the E34L/STR HARMA in the third column on the first page. That's what the Siemens I have and linked to are, rather than typical Siemens made by RFT, which they also rate farther down.

http://www.watfordvalves.com/cgi-bin/documents/testreport_46.pdf

H9

heiney9

As a side note; if you read the entire review I posted you'll note the 1st, 2nd and 3rd place valves (behind the Original Mullard and Original Tesla, of course) and I have all 3 of those EL34's and listened to them before finding/reading the review and those are pretty much how I rated them. The Winged C and E34L are very close, IMO. The EH's that came with my amp do a pretty decent job too.

H9

zingo

heiney9 wrote: »

http://www.ebay.com/itm/260763693094?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

This British guy has some sweet tubes! He is offering a quad of the Siemens EL34 for $205, which seems reasonable if they are as good as you say. I've seen that Siemens also made an E88CC which are not cheap, but reviews are very good, and thatpairing of German made tubes seem like they might be a dynamite combo...