+1 Keep your gain as low as you need to keep the drive down. Crank the master to compensate - in fact I would usually run the master at full and dial the gain up to volume for maximum headroom.
Distortion_101 wrote:
Now, can i try putting 5751 tubes in there (instead of 12AX7) without causing any damage to the amp?
Yup. Direct drop-in replacement. Usually just one to replace your 12AX7 in V1 - that covers two gain stages, so it's quite effective in increasing headroom.
I've heard also that 12AT7 are actually not a direct replacement for 12AX7 and people just assume so cause of the model number. Is this true?
Correct. If you look at the specs, the transconductance figures are similar between the 12AX7 and 5751, while AU7s and AT7s (the other popular replacements for AX7s) are way off.
has anybody else found the Cub12 with the rocket 50 speaker to be a little muddy? i don't know if this will get better the more the speaker breaks in, but its what Im finding.
Yes, the Rocket is a great speaker for inexpensive amps, but it does suffer in comparison to the better speakers in the Celestion range. And low end looseness/flub at volume is one of the biggest complaints. The amp does also suffer a bit from having a small cabinet, which isn't as easily rectified. If you want to be sure, take it to a shop and try the amp out with some extension cabs.
Anyways though, I have found a V30 for very cheap, and I'm thinking of swapping the speaker, but the V30 is 16 ohm and the stock cub 12 is 8 ohm. Is there a ohm selector in the amp so that I can use a 16 ohm speaker?
Off hand, I'm not sure if the output is switchable or not - check the manual. It might also have a different output for the 16 Ohm, rather than a switch. Either way It would need to be set to the same as the speaker, unless you can find another 16 Ohm speaker to pair it with in parallel.
