about to retube a MB studio preamp

[kirksflooring]

I just got a mesa studio preamp and opened it up today. There are 3 different kinds of tubes in it. There are JJ tesla ecc83s in the 1st and 3rd spots, and phillips ECG 12ax7wa in 2nd and 4th spots. Also an EH12ax7 in the spot above the four in a row. I've heard a lot about JJs, but very little about the phillips. Any opinions would be appreciated. I also have a 9100 marshall monobloc that has ten year old(at least) sovtek 6l6s that will also be replaced. Any suggestions on what to replace the power amps with?

 

[edgarallanpoe]

Don't know much about the Studio Pre-amp layout, but I have no idea why anyone would put a JJ instead of that Phillips in V1. The Phillips is a monster tube. It is fat an creamy sounding when overdriven. It is one of my all time favorites. I would swap those around and put that in V1 immediately and see what happens. Noise should be almost nil, and you might have to tweak the EQ a tad.

BTW Those are $50 a pop at any tube store. *Great* tubes.

IMHO the TAD 6L6s are the best current 6L6 on the market.

 

[Guitarzan]

Don't know much about the Studio Pre-amp layout, but I have no idea why anyone would put a JJ instead of that Phillips in V1.

I certainly would put a JJ ECC803 in V1. That's a nice tube. Also look to the Groove Tube 12AX7-M. The later would be my choice of tube for V1 position.

 

[edgarallanpoe]

That's a nice tube.

I know...I have a bunch. But it isn't anywhere near as good as the Phillips IMHO. The Phillips are dead quiet, built like tanks, and sound better. Granted, tone is subjective....build quality is not. The JJ can be microphonic in high gain situations, the Phillips won't budge. IIRC the Phillips is also higher gain.

 

[Guitarzan]

I haven't found that to be the case with the 803's. The 83's... yes! They are too harsh for a V1 position. .02

 

[edgarallanpoe]

I haven't found that to be the case with the 803's. The 83's... yes! They are too harsh for a V1 position. .02

Are you sure you aren't mixing these up? The 803 is the long plate, the 83 the short plate. In my experience the long plate get a little bright in the top end. The 83 does better in the microphonics dept, but sound sterile IMHO. I like the tone of the 803 better, but I wouldn't use it in high gain situations. Neither would KCA tubes...

Great in vintage and vintage style guitar amps. Not recommended for high gain amps.

 

[kirksflooring]

a few more questions... If I put the phillips in v1, which I assume to be the one on the far left as you look from the front, should the other phillips go in v3 or v4? Also, I have an EH12ax7 in the spot above the four, and it says to put a 12at7 there. What does that lone spot do and should I replace the current tube?

 

[Guitarzan]

I haven't found that to be the case with the 803's. The 83's... yes! They are too harsh for a V1 position. .02

Are you sure you aren't mixing these up? The 803 is the long plate, the 83 the short plate. In my experience the long plate get a little bright in the top end. The 83 does better in the microphonics dept, but sound sterile IMHO. I like the tone of the 803 better, but I wouldn't use it in high gain situations. Neither would KCA tubes...

Great in vintage and vintage style guitar amps. Not recommended for high gain amps.

Yes..I'm sure. I use the long plates in both of my heads. I use them to chill out my DR's.