Fender Super Twin.

[Marcel]

I know where you are coming from on that...

There is a simplicity and a danger in tube gear that solid state just doesn't have. When you think of it nearly all tube gear gets their results with typically less than 10 active elements. Some how I think, and regardless of how it may sound or cost, we will never see the day where a solid state 50W 2204 style amp will ever be released boasting only 8 transistors.

Yeah, the danger is all pretty much the high voltages at potentially lethal currents. 500VDC @ 300mA in a guitar amp is more than enough to switch off a human life... and if working on that gives you a 'buzz' then maybe old school AM radio broadcasting repair might be worth a try where 6kVDC @ 700mA is quite common and 25kVDC @ 1.5A over two serious power tubes in series is often encountered, The thoughts of working anywhere near those voltages make some break into a severe nervous sweat, whereas others like myself it is our day-to-day job ... go figure...

Regardless of all that my heart just loves hearing a good tube guitar amp. 2nd harmonic and even overtones sound so much better when produced by real tubes than the filtered third and odd harmonic overtones that are the more natural condition of solid state. I suppose it is all a question of balance really....

[DrNomis_44]

I know where you are coming from on that...

There is a simplicity and a danger in tube gear that solid state just doesn't have. When you think of it nearly all tube gear gets their results with typically less than 10 active elements. Some how I think, and regardless of how it may sound or cost, we will never see the day where a solid state 50W 2204 style amp will ever be released boasting only 8 transistors.

Yeah, the danger is all pretty much the high voltages at potentially lethal currents. 500VDC @ 300mA in a guitar amp is more than enough to switch off a human life... and if working on that gives you a 'buzz' then maybe old school AM radio broadcasting repair might be worth a try where 6kVDC @ 700mA is quite common and 25kVDC @ 1.5A over two serious power tubes in series is often encountered, The thoughts of working anywhere near those voltages make some break into a severe nervous sweat, whereas others like myself it is our day-to-day job ... go figure...

Regardless of all that my heart just loves hearing a good tube guitar amp. 2nd harmonic and even overtones sound so much better when produced by real tubes than the filtered third and odd harmonic overtones that are the more natural condition of solid state. I suppose it is all a question of balance really....

I think part of my fascination with Tube/Valve technology is that I'm tired of trying to work with components that require a magnifying glass and a pair of tweezers just to read the component values and solder them onto circuit boards, I prefer working with components that I can easily hold in my hands and read without squinting my eyes, I've found that in reality, surface-mount devices are not more reliable than conventional components, but if other people like SMD technology well then each to their own.

When a Valve amplifier distorts, or is overdriven, as you have said, they do generate even order harmonics, and they definitely do sound more musical, to my ears the difference between an overdriven Valve amp and an overdriven Solid-State amp shows up as a high-frequency crackling when a Solid-State amp is overdriven, a Valve amp sounds a lot smoother to my ears, it has a fuzziness in the high-frequencies, plus the distortion harmonics tend to be mostly in midrange and upper midrange frequencies, but the overall tone is more determined by the circuit-topology of the amplifier, my Marshall MA100C is an all Valve 100 Watt amplifier and the signal-path is all through Valves from the input through to the output, there is some solid-state circuitry but that's mainly for channel-switching, reverb, and the resonance control which affects the low end in the amps power-amp section.

And it's true, for a basic Triode gain-stage you need less passive components to get it working correctly than you need for an equivalent Bipolar Transistor gain-stage, you only need three fixed resistors to get a Triode gain-staged biased correctly, whereas a single Bipolar-Transistor needs four, yes there is the Fet (Field Effect Transistor) which is like a Solid-State equivalent of a Triode, but in actual fact, the Fet behaves more like a Pentode.


If you do know what you are doing and follow the correct electrical safety procedures then Valve amps can be safe to work on, provided that you keep your head screwed-on.