New DIYTube SET 6B4G Amplifier !

[TomMcNally]

Those of you that follow the DIYTube forum know that Shannon has been working on a new SET amplifier with the 6B4G. I had the pleasure of building one of the first prototypes. All I can say is it's sounds amazing ! It will be released sometime in March, with the typical great manual, with parts sourcing, and support we are used to from Shannon's other boards.
The circuit board is the driver, a 6SL7, and the power supply, with a 6AX5 rectifier. The 6B4G's (which are 6 volt octal based 2A3's) are chassis mounted. Output transformers are the James 6115-HS, powered by a PA-774 clone from Triode, mine has Ned's tubezone.us nickel plated covers.

Take a look ...




More pictures on my site at: http://mcnally.cc/amps.htm

This is a nice one or two evening project for the experienced builder.

... tom

[TerrySmith]

That looks really nice! Are those the Sovtek 6B4G's ? I've wondered about their quality and sound.

Is this the board that could be used as a linestage preamp also?

[TomMcNally]

Hi Terry -

Yes, they are Sovtek 6B4G's and 6SL7, the rectifier is NOS.
I have over 100 hours on the amp, I had it on a board until
I got the chassis today. I have to tell you this amp has more
solid bass than my 300B which weighs a ton.

You could use the board as a linestage, it's self contained,
very nicely laid out and a quick build. Quiet and sounds
great. You could delete the DC supplies for the 6B4G's if
you use it as a linestage.

... tom

[Shannon Parks]

Hi Terry,

Sorry I missed my Groundhog Day release date, but I have been steadily tweaking this gem along with Tom's help and advice. I'll probably buy the production run of boards this week, with a 3 week lead time. Keith at Euphonia should has his fresh shipment of James transformers from Taiwan in by then, too. Still ironing out the chassis details. I'll post a Front Panel Express file so that custom units can be built for whatever wood enclosure someone has or builds. The RCA inputs layout will also be modified some in the next few units and a volume pot added.

[TerrySmith]

This may be a nice project for a blank mk3 or ST70 chassis from Soundtastick.

Last fall I was at evsentry3's house, and listened to a 2A3 amp driving an open baffle speaker with amazing bass! At that point I was officially bitten by the DHT bug.

Is there a website for the output trannies?

[TomMcNally]

Terry -

There are links on my website ... http://mcnally.cc/amps.htm

Shannon can supply the Front Panel Express data file for the top plate,
which is really nice and easy to work with.

... tom

[sorenj07]

Hi, the amp looks amazing and as elegantly simple as usual, but what's the final pricetag as seen? Also, stuff like output power etc.? I don't think SET's are viable for me because I want some headroom but it'd be interesting to see nonetheless.

[TomMcNally]

Hi Soren -

The 6B4G is a 6 volt, octal 2A3 basically - same power - about 3 watts.

I would guess it would cost between $ 400 and $ 500 to build, depending
on whether you did your own chassis, or had one made. You could also
opt to go with other transformers, etc.

... tom

[TerrySmith]

Is there a schematic we can look at?? Yellow_Light_Colorz_PDT_06

[TomMcNally]

That's a question for Shannon !

[Shannon Parks]

get*set*go manual

getsetgo BOM for PCB
getsetgo BOM for hardware

Still in beta really, so I wouldn't encourage anyone to order parts until I release the initial parts list with the launch boards. Get*set*go has been a name I've thrown around - if it seems stupid, let me know and suggest one. The name getsetgo pays some homage to the Japanese SE and DH triode revolution, but mainly refers to the super fast nature of the build & sound. In other words, this ain't a three year project like some SET builds.

Rough Cost Estimate Less Shipping
- James 6115 Outputs from Euphonia $145
- PA774 Power Transformer from Triode Electronics $59
- 1.5H, 55 ohm DCR Choke $10
- diytube board $49
- PCB stuffin' parts $35
- Other hardware from Mouser $35
- Pair of Sovetk 6B4G $68
- NOS 6AX5GT $2
- 6SL7 $10
- Sockets $10
- Chassis $100 (the biggest flexible cost right now)

This rings up to $523.

[SteveH]

That is awesome, excellent work Tom and Shannon ! You are an absolute terror on my bank account :D

Tom - I am quite envious; I have forgotten what grass and blue sky look like...

[TerrySmith]

Steve, if you like blue skies, green grass and a mountian view, move here to east Tennessee!

If you built a linestage with this board, leave out the output tube cathode circuits and connect jacks at the 6B4 grid connection?

[EWBrown]

Nice lookin' amp!

I've got a place down in Clay County, western NC, not too far from E. TN and GA... Just a vaca place now, but in the next year or two, it'll be home sweet home, as I get outa the frozen wastelands of NH. Lots of blue sky and mountains!

Those SOVTEK 6B4Gs look just like the Sovtek and EH 2A3s, except for the octal base. I'd SWAG that the grid and plate assemblies are identical.

The new JJ 2A3-40 (40 watts plate disp, is somewhat different, it's basically a 2.5V filament 300B.

"Getsetgo" sounds like some strrange food items from the far east Yellow_Light_Colorz_PDT_08 Check out Andrew ZImmerns "Bizarre foods" TV show:
http://www.commonsensemedia.org/tv-revi ... ndrew.html

He had one a couple years ago, about really strange food from all around Asia...


/ed B in NH / NC

[SteveH]

Terry,
Actually DE isn't bad at all. Some nice rocky hills, etc. But I can vouch for down your way; last year I took a ride down there and hit up the tail of the dragon on my way home - quite a trip !

Regards,
Steve