Dehavilland Mercury tube swaps


A quick question to all Dehavilland mercury 2 owners.

Its only about tubes basicaly.
Have any one of you experience tube swapping the 6BX7 and the 5U4(5AW4) rectifier in this pre-amp.
I love the unit that i just acquired recently but always looking to experiment.

I noticed quite a few 5U4 or 5AW4 variants for sale on the net, does this rectifier make any difference in the Pre?
Also some older NOS 5U4 are shapped with a bigger glass above the bottom pin support and was wondering if these fit in the Mercury since half the tube is recessed into the chassis.Diameter maybe too big.

- 6BX7 tubes i think are worth eperimenting with, are these replacable by anything else because it seems very hard to find any info on these on the net, is there a NOS that fits the bill or a newer version with a different code?
Original Mercury tubes where 6BL7 tubes but when it was sent for an upgrade it came back with 6BX7 tubes, is there any difference between both?

Any feedback would be greatly appreciated.

Regards, Nick 72
128x128nick72

Showing 2 responses by nick72

I have a pair of(NOS) Tung-sol's black plate installed in the unit curently.
I think it would be hard to get better on that side.
The output tubes are 6BX7GT and i would love to roll these but i have a hard time locating some.
I have a few rectifiers( 5U4 type) on order for rolling.
a pair of Tung-sol 5AW4GT, a pair of raytheon 5AW4GT, a sylvania 5AW4GT, a vintage Hytron 5AW4GT, also a GE 5AW4GT.
so i think i will be covered in that field.
If anyone Knows where i can get some vintage sylvania or tung sol 6BX7 types please let me know.

Regards, Nick