Best 12AX7s for high gain preamps....

[Duke of Metal]

Re: Best 12AX7s for high gain preamps....

For the stock MP-1, I'd look into either the Highgain graded JJ ECC83S rated at 110mu+ per side (on each tube). those sound better than the "standard" off the shelf JJ ECC83S. More gain, no where nearly as dark but wont have that harsh highend.

I did some testing in an MP-1 a while back and the Highgain JJs where less noisey and tighter sounding than the EHs. Only thing with the JJs the gain controls needed to be cranked by 0.5 on each to match the EHs gain but still were lower noise.

your other choice is some Highgain graded chinese 8th generation at 110mu. or Highgain graded Chinese 9th generation. There is no tonal difference between the 2. The 8th generation 1 has something on the inside of it thats different from the 9th generation. but doesnt affect the tone.

The 9th generation ones dont come highgain graded at the 8th generation, but they're still pretty highgain even if you get them at 100mu.

if you'd like, check out www.adadepot.com's forum if you have any questions.

If you'd like, check the Mod4 Mark II mod for the MP-1. it gives the MP-1 tighter and thicker tone. very hot rodded thick marshally tone.

Hope that helps!


Good luck

 

[sosomething]

Re: Best 12AX7s for high gain preamps....

I've used a lot of different preamp tubes, but I keep coming back to the JJ's 12ax7s. Clear top, smooth mids, and a tight but present low end. I've tried and A/B'd all kinds of stuff so I'm not just touting what I use without any real perspective.

I tried the EH tubes, including a set of the EH gold pins, and found them to be almost TOO high-gain. I'm sure they work great for getting some extra crunch out of a relatively mid or low-gain amp, but for a bonafide high-gain head they were overkill, IMO.

 

[Fresh_Start]

Re: Best 12AX7s for high gain preamps....

I've spent parts of the last week swapping back and forth among the following 12AX7's in a Blues Jr. Some have been here for a while and others are new arrivals:

Electro Harmonix (been there a couple years) $9
JJ ECC83S $8
JJ ECC803S $12
Shuguang 12AX7C (9th gen. Chinese) $9
Tung Sol re-issue $15
Ei $9
NOS JAN 5751 $19
NOS JAN 12AT7WC $?? (old for me)

YES, it does make a difference which tube position you play with. "V1" is the first preamp stage and seems to have the biggest impact on tone and feel - it comes before any "Gain" or tone controls in the preamp circuit.

Just talking about V1, Christian's comments seem to be on the mark. The Tung Sols had the most gain of the bunch. The high end seemed a bit harsh/raw to me, but might be perfect for another amp or set of ears. The Shuguang is next highest gain, and sounds OK with pretty well balance tone. The Ei has the sweetest high end and nice gain but these tubes are notorious for being/going microphonic. Both JJ's are a bit dark for my taste, but they also have smooth highs and decent gain. The ECC803S sounds a little sweeter, but it could be my imagination. The EH's have been really reliable, but they don't have much character and are not high gain.

The 5751 in V1 produced much less gain, more clean headroom, and let me really crank the power tubes. With lots of reverb and the bridge pup, I got some serious cowboy twang! That'll be fun sometimes.

Please keep in mind that I didn't record anything and had to wait for the tubes to cool (while I actually worked ) between tests, so this is all super-subjective. Just my amp, my ears, my guitar, and my inept playing style.

The really interest part has been going back & trying out the tubes in V2 and V3. In the Blues Jr. only 1/2 of V2 is used as an additional gain stage after the tone stack. Putting the Tung Sol in there overdid the gain (for me), so the JJ ECC803S is in there now. V3 is the phase inverter (and no, I don't completely understand what that means). Others have recommended the 12AT7 for that spot, but for whatever reason I like the hottest Tung Sol there. Go figure!

All this is subject to me changing my mind in a week or two...

Good Gawd, I got tube G.A.S.!!!

Chip