My Vox Ac30 and my V1 V2 V3

[albano1973]

Bought a used Vox AC30CC2X recently and decided to replace the tubes as I think they're stock and the amp has like 3 years on playing on it

 

I'm in a band that plays regularly Northeast Boston and Brooklyn, so I want to make sure the pressence is there, you know?

 

So for the power tubes I'm going to put in JJs EL84s and also putting in a GZ34

 

so for the preamp tubes, I got advice for V1 to put like a JJ longplate ECC803S

 

I also read an article talking about the V3 PI and that they suggest a Sovtek 12AX7LPS

 

But I also keep hearing people saying to have a Tung-Sol over JJs

 

so I'm starting to think these 3 options before I move into putting things into reality and thought I'd ask for some input

 

Option 1 V1 JJ longplate ECC803S  V2 and V3 JJ ECC83s 

 

Option 2 V1 JJ longplate ECC803S V2 JJ ECC83s  V3 for PI consideration Sovtek 12AX7LPS

 

Option 3 Maybe get crazy V1 JJ longplate ECC803S V2 Tung-Sol 12AX7  V3 Sovtek 12AX7LPS

 

Kinda leaning towards option 2...Am I overthinking this and just should do something like option 1?

 

 

[t_e_l_e]

my first answer, if it ain't broken, don't try to fix it

 

if your amp works and sounds great why do you want to change the tubes?

 

i use the cheapest tubes available and don't care about NOS

so for preamp i use usually sovteks, depending on which amp and how much gain i want/need i select the "right" for V1

 

putting a 12AX7LPS with less gain output in V3 seems counter productive...

the biigest single change you get at V1 by controlling the input gain, decide if you want more or less...

 

but define your goal and then select your tubes, just putting some NOS stuff randomly in your amp will not help

[albano1973]

yeah I might be over thinking it 

[WRGKMC]

The differences between tubes is very little. Its going to be hard for you to notice a change, difficult for your band mates to hear any difference and the chances of your audience hearing a difference? They wont have a clue.

I usually stick with matching tubes all around. I've done all that kind of swapping around over the years and for some amp builds it makes a very small difference. If you want different tone you'd be better off trying different speakers. That's where you get the biggest bang for the buck. You can get higher SPL speakers and make the amp much louder, thinner speakers so you have more string touch come through, lower SPL to reduce the volume so it sounds better miced, and you have a wide variety of frequency responses for tonal shaping.

 If all you need is a small change go for it. Just don't expect a big difference. Changing string brands can easily produce double or triple the difference in tonal changes than a tube substitute can have in most guitar amps.

The reason is because guitar amps are midrange amps and speakers rarely produce any frequencies below 100Hz or above 6Khz. Where you hear the difference in tubes is with high end Hi Fi gear where the super highs and lows are heard. There you can hear the transparency much better but a guitar producing most of the frequencies between 500~4Khz, the bandwidth is just so limited the differences in tubes just can't be appreciated much.

Tube bias for the power tubes can make a difference. Some tubes have higher milliamp ratings and you can bias many amps up do they drive cleaner or break up easier. Some Voxes use class A circuitry and are a bit different than an A/B amp when it comes to drive. I wouldn't experiment much with biasing them hotter or cleaner. The old Voxes used to blow up regularly because tubes changed value over time and the circuitry design was pretty poor. I believe some of those flaws have been fixed in reissues but there's no sense in tempting fate.  

[Steve2112]

I've been swapping out tubes on a 1964 Fender Twin and JSX combo. The preamp tubes...in a real world application (like on stage) seem to make little noticeable difference. Certainly not enough to spend a bunch of money and headache about.

The JSX can use EL34 or 6L6...and there is see a difference...obviously. 34 are a bit more agressive and much louder. 6l6 are a bit softer and quieter. This would be preference rather than better or worse. 

 

I'm not a tech nor immensely discerning (don't get me wrong I like good tone and know it when I hear it)...but I don't reccomend messing with preamp tubes just to mess with them. Waste of time. Just have a "good" working tube in each socket and rock it out.