That's a good question. My guess is that he was maximizing the output power in your amp. In my communications with Dennis, he never recommends the 5AR4 / GZ34 for best sound. My amp, the 17 watt KT88 one, also is shipped with a GZ34 as stock, as that is the only way it can produce 17 watts. It makes 15 watts with a 5U4G.

That link doesn't work for me.

Try this:

https://drive.google.com/open?id=0Bw...EYza1l5SDhQNzA

Try this https://drive.google.com/file/d/0Bwg...ew?usp=sharing

Tube# - Base - Fvolt - Famp - Vdrop - MaxPmA - MaxPv - notes
5U4-G - 5T - 5.0 - 3.0 - 44 - 225 - 450 - octal 5Z3
5U4-GA - 5T - 5.0 - 3.0 - 44 - 250 - 450
5U4-GB - 5T - 5.0 - 3.0 - 50 - 275 - 450

Both quite helpful, thanks for the info!

Dennis seems to never list the 5V4 rectifier in his list of different rectifiers to use in his amps. I suspect it is because it isn't very common. I happen to have 3 that I got out of a big bag of tubes several years back. I like them. I'm using one to drive 6V6s in my amp right now. It pushes those tubes a little harder than a 5Y3GT, but less than a 5AR4. It's indirectly heated, like a 5AR4.

I had my amp and the 6V6s running for about 6 hours today. Quite enjoyable. With those lower wattage power tubes, the output transformers were only slightly warm even after 6 hours.

Nice documentation! Thanks

After additional tube rolling this summer, the 5V4 is now one of my favorite rectifiers. (And they’re cheap.) I have a variety of USA 5V4G and 5V4GA, with more on the way.

One of my favorite combinations is now KT150 / 5V4 / 6DJ8.

The 5V4 also sounds good with the 6L6GC tubes. A particularly good looking combination is the new production Tung-Sol 6L6G (large ST shaped 6L6GC) and 5V4G (ST shape).

My other favorite sounding combination is: GT6L6 GE (performance rating 5) / 5AR4 / 6DJ8.

These results are based on my Inspire “Fire Bottle” SE Stereo Tube Amplifier HO (originally equipped with KT88 / 5U4 / 6CG7), Klipsch RF-7II, and Klipsch R-115SW sub, playing a wide variety of classical music, plus some big band music.

I have some vintage 6L6GA (ST shape) arriving tomorrow …

I'm not sure that you can infer that statement from the Moon Audio Quote. Dennis will use whatever sounds good and doesn't red plate the outputs or arc the rectifier. Our last listening session we rolled everything from a 5R4, 5Y3, 5U4 and a 5AR4 through the amp. The main thing is that each of these different rectifiers have a different voltage drop effect on the B+/Plate voltage, and it would be possible to over power some tubes, especially older 6V6 variants with the smaller voltage drop variants. Another consideration, although not in these amps, is not using a rectifier with a filament current draw higher than the filament current rating of the power transformer. For example, a 5U4 draws 3 amps and a 5AR4 draws 2 amps. If your PT is only rated for 2.5 amps/5V, you can burn out the filament winding, or overheat the PT....

Quick Question
 

Analog Addict,

You seem to be the most plugged in to what Dennis is working on; I have a LP-27a, KT-88HO, and as of next week will have a PSE. What I don't have is a tube phono preamp (I'm using the phono stage of a modified Superphon Revelation Pro Basic right now). Do you know if Dennis is planning on offering a version of your phono stage?

Thanks,
Randy

Great info.

I have on order right now a Preferred Series 274B for the rectifier.
I'm trying out a full Psvane kit for the input/output tubes. Psvane 6SN7 + Psvane KT88 pair.

I like NOS tubes, but I also have had good experiences with new tubes.
I'll post some impressions about the Psvane stuff once I get it, since I searched this thread and didn't find anybody trying them out.

If I go mad with rolling, I'll probably get Mesh tubes all around :scratch2:

Randy - as far as I know he's not planning on offering a phono pre amp anytime in the near future. Best alternative at this time would be for me to build you one with him looking over my shoulder.

If you'd like an idea of the quality of my work, go to Audiokarma's tube forum and search for the "Finally starting my 27/56 pre amp build" thread.....

I have Sylvania 6L6GAY's don't run them with a 5AR4. The 5V4 may be ok, Run them in the dark and see if they red plate.

Pull out your wallets boys!
 

Heard from Dennis today about his newest phono preamp build....

Hey Allan, behind your back I have been readying a new revolutionary phono preamplifier. It is just about ready. The tube line up is as follows ….. 8 units of the 27 tubes for pregain MC stage followed by 10 of the 56 triodes as the passive RIAA section and then 4 parallel 6V6 tube as the output. The power supply is fully regulated 3000 volt design for maximum output and electrifying clarity!!!!!!!! Hook that to your tone arm!!!!! You will get a one time cartridge needle drop on the record sound like you ain't never heard before, one time only that is

Lol

Am I reading that right? 22 tubes in a phono pre?

Boom, baby!

As much as I might like Dennis to make a phono preamp, I got lucky with a PH3 locally. He's a funny man, Mr. Had.

Yeah I told him that the instant the stylus hit the record, all the tubes were going to explode....

I too like the Psvane tubes. The KT66z works well for me.

I have these CV181's: clear glass UK series, Psvane CV181-T Mark II bronze base and Shuguang Treasure CV181-Z white ceramic base. Not a dog in the bunch. I've had good luck with seller hsalience and Ice Lake Audio on the auction site. Be sure that you are getting premium series tubes.

Which mesh tubes are you considering? I bought 5 Full Music 274A, a 4 pin version, perforated plate rectifiers for a great price. There some posts here about the Sophia and EML tubes.

I'm thinking about the EML 5U4 or 274B for the rectifier.

I can't find any mesh alternatives to the output/input tubes, I wonder if any exist?

Anyone here with experience with a 6N8S? I ordered 1 today to try as a driver tube. I hope it is worth the $.

How much did you pay for it? I've seen the Russian ones going for $2 each. I know the older, metal base ones are pricey.

Metal base, round holes in plates, quoted as NOS,... $75+shipping.

From another forum:

I have a pair of EML 5U4G tubes and use them from time to time. I also use NOS Brimar, GEC, Marconi 5U4G tubes. I find the EML 5U4G´s just as good as the NOS tubes, nice glow due to mesh. The only down side is their size, they are BIG!

Me? I'll pass. However, I have considered them. :D

EML does have mesh plate triodes. There are no mesh plate pentodes or any other mesh power tube that will work in these amps.

FB,
Could this be the same people?
amazon.com/sp?_encoding=UTF8&asin=B01E57OA72&isAmazonFulfille d=0&isCBA=&marketplaceID=ATVPDKIKX0DER&orderID=&se ller=AT9HPTJQR9BRT&tab=&vasStoreID

Looked on the auction site and found a previous seller that went by Salience HiFi but no recent activity. Quick google search turned up the Amazon web store. Looks like they may have moved there business from the auction site.

If so, I am gonna order one of the UK CV181 to try on my 45 SET.

PS: Still in FL? Im over on the Treasure Coast myself.

I can (I think) hear differences when I switch between 5Y3, 5V4, 5U4G/274B, 5U4GB (I think I hear a tiny difference between this and 5U4G, but wouldn't bet money on it in a blind comparison), and GZ34. But within rectifier tube types, say a vintage Sylvania 5U4G vs a vintage RCA 5U4G vs Tubestore Preferred 274B, I am not convinced I can hear any differences. Many tube amp owners say the same. So I've decided to not spend a lot of money on rectifier tubes. Dennis has told me that he considers the low cost JJ GZ34 to be very good.

However in my comparisons of 6SN7 tubes, I did consistently hear differences. I have 7 of them, and each one sounds a bit different, a couple of them a lot different. A couple have brash upper midranges which can be pretty aggressive. Another one is both recessed on highs and flabby/loose in the bass. The difference is immediate.

Despite their reputation as frequently being noisy tubes, I haven't found that to be the case with mine. I turned up the volume a long way with no signal and could not hear any hissing, pops, noise at all. And this is through Focal speakers with their detailed tweeters. No humming either.

I have found that I can "tailor" my sound a bit via my selection of 6SN7 tube.

Mistaken post. Please ignore.

In my rig:

Inspire KT-88 SET amp with 20 Watt trannies and DACT step attenuator; LP-27a Inspire preamp with DACT Step attenuator; Yggdrasil DAC; Tekton Lore 2.0; Velodyne DLS 3500 R Subwoofer

Preferred combinations:

No. 1 (Best sound):

Decware Zbit (Balanced; No preamp);

Amp:
Super Radiotron 6SN7 GTA; Sophia Electric 274-B Mesh Plate; Russian 6P3S-E

No. 2:

Preamp:
GE 6BX7 GT, RCA Radiotron 80, Silvertone RCA 27*

Amp;
Super Radiotron 6SN7 GTA; Sophia Elecric 274-B Mesh Plate ; Russian 6P3S-E

No. 3

Preamp:
GE 6BX7 GT; RCA Radiotron 80; Silvertone RCA 27*

Amp:
Super Radiotron 6SN7 GTA; Sophia Electric 274-B Mesh Plate; Genalex GL KT88

No. 4

Preamp:
GE 6BX7 GT; RCA Radiotron 80; Silvertone RCA 27*

Amp:
Phillips JAN 6SL7 WGT; Sylvania 80 (Green); RCA 6V6 G ST

*Most of the time, the Silvertone Balloon-type RCA 56's in lieu of the equivalent 27's, produce the same results!

YMMV

Just for your reference, these are all the tube candidates at hand:

NOS Russian 6P3S-E
NOS RCA 6V6 G ST
NOS RCA 6V6 GT
NOS TungSol 6AR6WA w/Adptr
GENALEX Gold Lion KT-88
NOS Philco Globe-Type 27
NOS Philco 27
NOS RCA 27
NOS Sylvertone Globe-Type 56
NOS RCA-Radiotron 56
NOS Silvertone RCA 27
TungSol 6V6 GT

Sophia Electric 274-B, Octal
NOS RCA Radiotron 80
NOS Sylvania 80
NOS RCA Victor 80
NOS RCA Cunningham 80
NOS JAN Sylvania 80
NOS RAD-TEL 5Z3 (4-Pin)
NOS RCA 5Z3 (4-Pin)
NOS Brimar 5Z4 GY (Octal)
NOS Westinghouse-Holland 5AR4

NOS RCA 6SN7 GT
NOS Sylvania 6SN7 G/B
NOS Sylvania 6SN7 GTA
NOS Super Radiotron 6SN7 GTA
NOS GE 6SL7 GT
Tung-Sol 6SL7 GT
NOS Sylvania 6SL7 GT
NOS Phillips JAN 6SL7 WGT
NOS Tung-Sol 6SL7 GT
NOS GE 6BX7 GT (Preamp)
NOS JAN Phillips 5691
NOS 6N8PJ (Chinese)

Speaking of Pope 6SN7 tubes, someone is offering a pair on Agon for $600!!! My goodness! They would have to sound extremely good.

That's funny! They are excellent tubes but not $600.

Same folks. h_salience is the seller id. The UK version is very transparent and open sounding. All the Chinese CV181's are good tubes just different 'flavors'. I just searched their fleabay store and they only have pairs of the UK version.
Can you get a single tube on Amazon?

I'm near Ft. Myers.

The new GL GZ34 is also very good.

IMHO, using the right rectifier..the one that delivers the right amount of B+ voltage for a given tube to sound 'right' in your system is more important than the brand.

You should get another quad of the 6P3S-E. That appears to be your favorite power tube. The good ones are getting hard to come by. :thumbsup:

Try the amp with an 80, Sylvi GTA (bottom flashed getter is preferable) and the 6V6Gs. I might also dig up a 5Y3 rectifier...

I haven't popped for any 6P3S-e tubes. Have read mixed reviews of them, most of them positive but not all. Tube Amp Doctor says that today's Sovtek 6L6WGC is the same tube and that they substitute one for the other depending upon what they have in stock. Others say the 6L6WGC is the standard 6P3S, while the 5881WXT is the 6P3Se. Confusing.

Here is a good guide to the various versions
http://www.jayskyler.com/guitar-gear...ube-guide.html

Cheap enough, maybe I should try them.

Do you mean a Sylvania GTA (bottom flash getter ) 80?

I thought all the following I had listed are equivalent to the 5Y3 you suggest, except these are 4-Pin (I use them w/adapter) and the 5Y3 is Octal:

NOS RCA Radiotron 80
NOS Sylvania 80
NOS RCA Victor 80
NOS RCA Cunningham 80
NOS JAN Sylvania 80

Is there something I'm missing? Thanks for the feedback.

Perhaps the 6SN7 is a GT version, like this one....

http://tctubes.com/images/products/d...GT_SYL_800.jpg

And yes, the 5Y3 and 80 rectifiers are supposedly electrically identical, but Dennis and I found that even though the distortion curves didn't necessarily change much, we were able to notice a significant sonic difference between rectifiers.

I bought a quad years ago from Jim Mc Shane and sent two of them to Musica. They are a coin base tube and good ones are getting hard to find.

Search both 6P3S-e and 5881WXT you'll see the difference. I have no clue who a good seller is now. I just looked at both on fleabay and it is confusing. The military one are from the 70's-80's and have a gold grid.