TH30 fizzy sound - change tubes?

[Exxeca]

Hi there,

I really like the dirty channel of my Orange TH30, but the sound is always a bit fizzy. After some research I found out that changing the preamp tubes may help.

So my question: is it possible to replace the V1 (ECC83) with a JJ 5751 but still keep the ECC83 in V2?

[Ronnie Robinson]

Fizzy?..... how loud are you running your master volume? and how old are the Preamp tubes? If they are older than 2 years yes Id change them, I'd also change them whatever age if they were chinese tubes.

[Phlowen]

I know exactly what you mean. That's the transformers of the TH30 (and the Dual Terror): They're not the best (but that's part of what makes the amp more affordable). I ended up upgrading my transformers and that took care of the issue, but it's an expensive solution.

I'd be interested in hearing if you can reduce/eliminate that fizziness with tubes. Let us know what you find!

[secretsoundz]

Hi there,

I really like the dirty channel of my Orange TH30, but the sound is always a bit fizzy. After some research I found out that changing the preamp tubes may help.

So my question: is it possible to replace the V1 (ECC83) with a JJ 5751 but still keep the ECC83 in V2?

Yes, the JJ 5751 will help warm it up and make it a little smoother and less fizzy/harsh.

You can always mix preamp tubes for a 12AX7/ECC83 as long as they are compatible dual triode types like 5751, 12AT7/ECC81, 12AY7, etc.

[Jondog]

I can't say for the TH30 because I don't have a schematic, but on Tiny Terror and a Dual Terror I've cleaned the fizziness up by lowering the phase inverter cathode resistor value.. Modern Orange's tend to have a 1.2k resistor there. Put it down to an 820 ohm or so. 820 ohm is actually the value on the AD30 and AD15 phase inverter cathode resistor. Tube changes work sometimes.