goldtop0
Well-known member
- Joined
- Aug 19, 2003
- Messages
- 8,931
Any of you guys got this combo with the 12" Cannabis Rex speaker.
I presume there is no PCB in sight?
I presume there is no PCB in sight?
Good lord, there's a surprising lack of knowledge of this amp here.............so be it:hmm
Printed circuit board yes, but maybe no semiconductors?:
Cool pic.
Looks like Fender stuck with the 22uF in the first filter stage. Very common for techs to bump it up to 40uF when replacing the cap can on the old ones. The bias pot is a nice touch.
What effect does the use of a 40uf cap have.
Mostly tightens up bass response and also buys a couple watts of headroom.
That's a very positive effect...........thanks for that info:salude
It's a balancing act. The cool and funky vibe of a Princeton Reverb is partly due to what some consider the amps "deficiencies." Every little mod that is designed to address these quirks inevitably takes away a little bit from the uniqueness of the amp. If you go too far one way toward making the amp band friendly you lose what makes a PR such a fun amp to play and record. At that point you might as well go and get a Deluxe Reverb.
The bump to 40uF in the filtering has proven to be stable in the PR, especially with a GZ34 rectifier. Those little weeny power transformers also appear to be able to handle it. It's not going to be as dramatic a shift as going to a loud and efficient 12" speaker, but it does help to clean up a little of the bass frequencies without sacrificing too much of the PR flavor.
Getting my head and playing around this PR now, it's good up to 7/8 on volume(LP dimed) above that I have to be really careful with low E and A playing as it flabs out.
Will leave the Gold in it for the time being.
Depending on how hard the amp was played before you bought it fresh power tubes and a bias might help.
The 40uF in the first stage does take away a little of the PR funk, but it helps tighten up the bass. The originals ran a 20/20/20 cap can configuration and many techs recommend bumping the first stage in the can to a 40/20/20 when people go in to replace the electrolytic caps. Weighing my options I went 40uF in my clone and don't regret it.
Hot bias isn't anything over the top, basically 70% dissipation. Some players (and Fender factory) like it slightly colder, around 60-65%. If your tech is willing he can adjust bias while you play to dial in what you like best.