Gu50

[cristelu2006]

Hello!Please can you help me with some plans of PP GU50 and eventually with the data of output transformers.
Thank you!

 

[azazello]

Gu50 Post #1
Hello!Please can you help me with some plans of PP GU50 and eventually with the data of output transformers.
Thank you!

Friend!
Welcome to me - Bulgaria, /very close to You/, and You will hear my amp GU50 and another tube amps and accust. system.
We will talk about Your PP project.
1.I use for SE output transf. Hammond 125 FSE
2....I will waiting for You....

 

[cristelu2006]

GU50

Hello! Thank you for the replay.This is the plan i want to make.
http://img18.imageshack.us/img18/6555/schemaoriginalagu50i.jpg

 

[Funker]

Hi Christelu,
you will find a superb homebrew version of an GU50 Amp here:

http://www.christl-ludwig.de/neueseite1_old.htm

This guy has designed a 160W mono and a 2x120W stereo amp. Each channel employ 4 GU50 or the WW2 equivalent LS50 (tfk)

The HP is written in german but the pics an the circuit diagrams speaks for themself.

Its contains also the trafo windings scheme and a suitable power supply.

A real "Eisenschwein"

regards
Wolfgang

 

[Wavebourn]

Here is 2x80W stereo amp, uses GU-50 output tubes.

 

[rdf]

Didn't that end up on e-bay?

 

[Wavebourn]

Didn't that end up on e-bay?

Yep. To cover expenses on pats used.

I'm building a new version now.

 

[Asatplayer]

Im amazed at how little te heaters draw on these tubes.
I bought a quad of them this week, with sockets, just on the appeal of the look and the wattage. way cool.
Came from sovcom too, paid very little for them, in fact got 2 RFT 12AT7's as well i paid the same for them!
I maybe dreaming, but amp planning a build of a bass guitar amp for a friend first, then for a customer if it works out. Looking at combining a couple of ampeg schemos.
Google GU50, and its this forum that gets all the hits!
Oh, my first post too
Hope the GU50's make a cool, very clean bass rig, should be frustrating fun finding out!
Don

 

[Jeb-D.]

GU50 seems like a good choice for a guitar/bass amp. They are built sturdy and have some pretty serious snap in sockets available.

Speaking of the sockets....have you plugged any of the tubes in the wrong way yet?

 

[Asatplayer]

GU50 seems like a good choice for a guitar/bass amp. They are built sturdy and have some pretty serious snap in sockets available.

Speaking of the sockets....have you plugged any of the tubes in the wrong way yet?

Ive not actually got my hands on them yet. Should be here in a week. Then i can go ahead and put them in wrong!
I have a pretty decent idea of the schemo im gonna try, trying to work out the order for transformers is tough. I order direct thru heyboer for my usual guitar amps, they have been great. Im just trying to work out the spec i will need to run a quad of these GU50's, and how im gonna get the screensupply lower, and higher heaters. Hmmm. I can order multi taps, for 5 dollars extra a tap, so if it all gos to hell, im gonna get taps to suit the standard ampeg with 6550's. Make it all usable.
Should be interesting!

 

[Matt BH]

I have been thinking about buying an 8 pack of these. I found a few designs.
Sorry I have no links. There is some great info on Jogis site. Also Elektor featured an article by Gerhard Haas, using EL156. This whole series is esentially similar. So most EL15XX designs could be used.
It would be interesting to know if the Chinese are still making the EL156 with an octal base?.

 

[Gordy]

It would be interesting to know if the Chinese are still making the EL156 with an octal base?.

Yes, they are.

: )

 

[Asatplayer]

I have gotten my tubes this week. For the life of me, i cant get the damn things out of the socket/cage thing. Pulling on the knob at the top with all the strength i can given the available grip is producing no results.
Anyone have some clues?

 

[costis_n]

I have gotten my tubes this week. For the life of me, i cant get the damn things out of the socket/cage thing. Pulling on the knob at the top with all the strength i can given the available grip is producing no results.
Anyone have some clues?

Same thing happened to me , when i got mine. So.

Spray the base/pins with contact spray (with oil).
Insert small flat screwdriver between base and glass.
Twist c-a-r-e-f-u-l-l-y to loosen . Repeat on the other side.

After it has lifted for 3-4 mm, it will come off. Then you can spray and wipe the pins and the socket, so that next ime it will be a little easier. Actually tou need a specialised tool to get them out of their bases....