Mad John
Member
- Messages
- 696
My Bruno Underground has been my main amp in the studio these past four years. I use all NOS tubes, but have had mainly "American" tubes in the amp - RCA AX7s and 5 GE EL84s.
I just put in a quad or Mullard EL84s and I could not believe the tonal difference! There is less head room. The Underground starts to break up a bit at 10-11:00, where with the Genral Electrics, about 1:00 to break up.
But the Mullards clearly have a richer tone! They sound more complex and yet still have chime and sparkle.
I feel that the Underground 30 sounds like the famous Mythological amp that it was rummored to sound like, due to rare availability outside of New York (new ones.)
I would say the amp has jumped up 45 percent in tone, meaning it is THAT much MORE of an amp with these power tubes in it! It makes my Stratocasters (Ron Ellis PUs) sound much more organic and present! I am getting more use out of rolling volume back on my guitar and still maintaining full rich tone with bite and chime!
Who could ask for anything more?
So I just had to share with you all this (to me) amazing tonal discovery!
Mullard El84 in quad (4) go for over $400! So I never even tried...I had GEs, I thought how much better could the Mullards pound for pound (or dollar for dollar) be than what I alreadt have.
The GEs cost me $250 and they have been well worth it...not causing any problems for four years of constant studio work!
I got the Mullards for $98.00!
Needless to say, I am very very happy with my tone on the Bruno!
Cheers mates,
I just put in a quad or Mullard EL84s and I could not believe the tonal difference! There is less head room. The Underground starts to break up a bit at 10-11:00, where with the Genral Electrics, about 1:00 to break up.
But the Mullards clearly have a richer tone! They sound more complex and yet still have chime and sparkle.
I feel that the Underground 30 sounds like the famous Mythological amp that it was rummored to sound like, due to rare availability outside of New York (new ones.)
I would say the amp has jumped up 45 percent in tone, meaning it is THAT much MORE of an amp with these power tubes in it! It makes my Stratocasters (Ron Ellis PUs) sound much more organic and present! I am getting more use out of rolling volume back on my guitar and still maintaining full rich tone with bite and chime!
Who could ask for anything more?

So I just had to share with you all this (to me) amazing tonal discovery!
Mullard El84 in quad (4) go for over $400! So I never even tried...I had GEs, I thought how much better could the Mullards pound for pound (or dollar for dollar) be than what I alreadt have.
The GEs cost me $250 and they have been well worth it...not causing any problems for four years of constant studio work!
I got the Mullards for $98.00!

Needless to say, I am very very happy with my tone on the Bruno!
Cheers mates,