Marshall Offset

[LOVETONE]

"T.B.R. Electrics" I think that became T & R music, I bought a stright front 4 x 12 new from them in 1976, the good old days.
Geoff

 

[LOVETONE]

Just checked, they are still there now called "T R Music" They still have the same phone number 01922 613101 amazing after all these years.

 

[tomsvintage]

Hope you and the family are feeling better soon ! Thanks again for the great close up pictures !!

 

[JeffH]

That's beautiful!

Congrats!

 

[neikeel]

Thanks for sharing. Despite some minor and neat resto work it is the most genuine one of these I have seen (Ma shallheads is nice too!!)
Hope to hear it wh n family better!

 

[Two Alpha]

Thanks for all the pictures of this beautiful old amp pleximaster, and congratulations on acquiring it!
One thing that caught my eye was the twisted filament wiring, this amp looks to me like the wires were twisted by a left hander.

 

[London John]

Send the photos to Ken Underwood and see what he thinks.

Oh, and the tolex looks good to me. Any chance of interior pics of the head cab?

 

[neikeel]

So You are mow running the preamp heaters off the front 6.3vac tap and the outputs off the back one? Running them all off the front tap will only work for low heater current 6L6s, KT66s would draw too much current from one set of heater taps. You see the later amps with the self wire heaters have the dark green and grey/black wires doubled up and routed up the middle between the PT and the board.
Looking carefully a the board it seems quite a lot has been restored with newer carbon comps.

 

[pleximaster]

inside and glove compartment. I did´t get the screws but they are flat slotted brass it seems.

Best Lenny

 

[pleximaster]

.

 

[pleximaster]

John!

I send Ken Underwood a message on FB!

best plexi

 

[pleximaster]

So You are mow running the preamp heaters off the front 6.3vac tap and the outputs off the back one? Running them all off the front tap will only work for low heater current 6L6s, KT66s would draw too much current from one set of heater taps. You see the later amps with the self wire heaters have the dark green and grey/black wires doubled up and routed up the middle between the PT and the board.
Looking carefully a the board it seems quite a lot has been restored with newer carbon comps.

Neil

Yes there are a few changed carbons but I knew that then I bought it and it can be fixed... Remember

Heaters
I just us one set for both pre and power tubes

Do you mean I should double them using both at the same time? How do I wire that? As the MT with flying leads? Just double them , I ´ll have 5.5 A then. Could I just link them on the transformer? Are they separate windings?

Best regards plexi

 

[neikeel]

They are separate windings. On mine I used the 3A for the outputs only and 2.5A for the preamp tubes. Look at this early Matamp and you will see how they did it:

The nearest yellow/blacks are the GZ34 heaters, the next are the output heaters. Furthest away are the preamp heaters.
ECC83s will draw 300mA each.
An EL34 1.5A each, a 6L6 just under 1A each and KT66 1.3A and an EL37 1.4A.
So you see if you are only using one heater tap for 6L6s you will be drawing 2.9A, a pair of EL34s 3.9A and KT66 3.5A. All higher than the 3A pair on your PT alone.

 

[Wildeman]

What a cool amp, Congrats

 

[pleximaster]

They are separate windings. On mine I used the 3A for the outputs only and 2.5A for the preamp tubes. Look at this early Matamp and you will see how they did it:

The nearest yellow/blacks are the GZ34 heaters, the next are the output heaters. Furthest away are the preamp heaters.
ECC83s will draw 300mA each.
An EL34 1.5A each, a 6L6 just under 1A each and KT66 1.3A and an EL37 1.4A.
So you see if you are only using one heater tap for 6L6s you will be drawing 2.9A, a pair of EL34s 3.9A and KT66 3.5A. All higher than the 3A pair on your PT alone.

Thanks Neil! Then the old I have 6L6 are going in today!

Should have send this one to you like Tom did with his amp. That ws a beautiful work you did there! I am an amateur i restos compared to you!

Best regards

 

[tomsvintage]

inside and glove compartment. I did´t get the screws but they are flat slotted brass it seems.

Best Lenny

 

[tomsvintage]

Plexi ~ Here is a link to my early JTM45 for comparison. I am looking forward to the video clip !!

https://www.facebook.com/Toms-Vinta...75/photos/?tab=album&album_id=190660701140110

 

[neikeel]

Yes, you can see on this amp of Tom's that the RS selector on top type is running both pairs of 6.3v heater wires to V 5 and then on to the chain. His is slightly unusual as it has the white wires to the lamp at 6.3v running with them. More normally would be 240v off the switch.

 

[pleximaster]

I put in the 6L6GC tubes from 1962 in the amp and some mullards preamp tubes. The GZ34 mullard I had was tiered so I used the TAD that came with the amp. I just made two quick and dirty clips with my iPhone.

I used a Les Paul and an hotplate -12db as the kids are off to bed. Cab was a Marshall 1x10 for the 1 watt offset (I didn't feel like hauling out a big 4x12 cab.

Sounds ok as is, but just for my personal satisfaction I'll find the nos parts like the replaced resistors.







plexi

 

[tomsvintage]

Oh Yeah !!!! Does the 1st clip start with Purple rain !!!?!!!

2nd clip Gary Moore " Still got the blues " ?

It's alive !!

Excellent range from crytsal clean to heavy grind