Yet another tremolo thread...

[AmberB]

A question for the hive mind...
If a person was contemplating building a bias vary tremolo circuit, like the Fender, for instance, which tremolo has more intensity and speed control, the dual triode design of the old 5E9 and 5F9 Tremolux, or the more recent 1 triode version such as the Princeton or Deluxe 6G3?
I realize that most of the later Fenders used the "vibrato" roach circuit, which is not what I'm looking for.
I was looking past threads, but I didn't see much discussion about the sound difference between the single triode and the dual triode bias vary tremolo...
Side note, this started because I'm trying to optimize the tremolo on my 1970 Princeton non reverb amp...I found the info I needed for that.

[sluckey]

It would be useful to know which amp circuit you plan to put this tremolo circuit in.

[AmberB]

It would be useful to know which amp circuit you plan to put this tremolo circuit in.

I have the guts from a tube powered record player that uses a pair of 6V6s in push pull.  The B+ voltage is not real high, if I remember, it's somewhere around 300 volts, maybe a bit less.  I had built a mini 5F6A in the chassis, but I recently took the parts out of the original chassis, which was small and rather tight, and am going to rebuild it in a more spacious chassis.  It will still be a push pull 6V6 amp.  My plan is to build something similar to a silver face Princeton.
The amp was cathode biased, so I will probably have to build a negative bias supply and convert it to fixed bias for the Fender type tremolo.

Also, I'd like to build a tube powered stand alone tremolo if I can figure out how to do that.

[Esquirefreak]

A single triode is usually (if the tube is strong) enough to wiggle the grid of a 6V6. A colder bias on the power tubes makes the trem effect greater.

The dual triode trem is good when wiggleing cathodes of preamp tubes or the grids of bigger (6L6) tubes. However, injecting trem on the grids of bigger power tubes is a bit finicky. It's often a compromise between weak trem or thumping speakers...

At least that's what I've found in my builds and experiments.

/Max

[sluckey]

The single triode tremolo as found in your Princeton works well with 6V6s. Doesn't matter if its cathode or fixed bias. You can make the tremolo much stronger by replacing the cathode resistor/cap with a 5mm red LED. The LED will also allow a wider speed range.

You may be interested in the Revibe, a stand-alone reverb tremolo unit.

[HotBluePlates]

... which tremolo has more intensity and speed control, the dual triode design of the old 5E9 and 5F9 Tremolux, or the more recent 1 triode version such as the Princeton or Deluxe 6G3? ...

Do I need to wiggle a 1 ounce object, or do I need to wiggle a 100 pound object?

Wiggling a preamp tube cathode is "easy" because it only takes a small voltage, but "hard" for a tube plate because the circuit impedance is so low.

   Fender's original improved tremolo in the 5E9 Tremolux wiggled a phase inverter cathode, so the oscillator got a cathode follower buffer.

   Fender's 5G9 Tremolux likely retained the cathode follower buffer not from necessity, but because it was already there in the prior model.

   Fender subsequently dropped the cathode follower buffer in the 6G3 Deluxe and blackface Princeton Reverb because they're wiggling relatively high-impedance output tube grids.

   But Fender retained the cathode follower buffer when the Vibro Champ wiggled a low-impedance tube cathode again.