another upgrade question. i have a randall rh300 valve-dynamic amp head. it's a single tube in the pre-amp and the rest is solid-sate. i love tube amps, but needless to say in this case, am set back by the overwhelming prices. so this valve-dynamic thing has been working out pretty good for me. i recently been thinking how i can upgrade my rig. so my question is how should i go about upgrading this amp head? is it possible to rig it up to have more tubes, or change up the circuitry, etc? basically if anyone is familiar with this valve-dynamic technology, can i improve this amp head in any reasonable way? thanks

Upgrading the circuiting on a amp should be left up to the pros. Please do not try to modify the circuit until you know all the precautions. High Voltages can really kill you. The negatives out weigh the positives in this dilemma. With the time you will take to learn how to modify a circuit to the costs of the parts or costs to pay a pro your better off buying a tube combo amp.

I find that the preamp valves supplied from the factory in hybrid amps of this type aren't great quality.
Try swapping the valve for a really good quality one like a Groove Tube or something

Did you know Fender owns Groove Tubes now.

I think Randall use Sovtek.. not 100% sure.

Does Groove Tubes make tubes or do they just take them and make them better, rate them?

Also have you guys tried Telsa Tubes? I put a set in my 800 Marshall combo and I like them.

what makes groove tubes better in comparison to other varieties? i might as well check out the tube threads, but i just want to know is there really any desirable difference to expect if i was to replace the 12AT7 tube in my preamp?

I just looked up the specs: This amp is not cheap. How does it sound with pedals?

300 Watt head with new "Valve-Dynamic" power
2 channels w/3 modes
Gain 1: Classic hi-gain
Gain 2: Modern hi-gain
Voicing and Contour controls.
Clean channel w/boost option
Dual 3-band EQ's,
12AT7 tube driven MOSFET power circuit
Spring reverb
Effects loop w/level controls
Line out

honestly, i've never been a fan of distortion pedals. but as far as eq, i use the mxr 10 band equalizer pedal and it really powers the amp up. the amp sounds very "crunchy" and it's fairly low-end. mainly, i just want to spice it up a bit, add something "extra" to get a more "epic" sound.

Replacing the tube will give it a little more bit maybe warm it up a bit but that's about it.