Tube amp questions

[EAdanikDG]

Hi, I saw on the decription for a Markbass R500 that the tube pre-amp breaks up like a real tube amp (eg. Ampeg SVT), which left me wondering.

Why don't other hybrid amps break up using only the gain control, does the "tube tone" come from the power or preamp, and what's the point of spending thousands more on an all-tube if not? Thanks.

[jordie65]

most of the hybrids ive encountered have a gain or drive option. i don't want to be that guy but if you do a search you will find some great discussions on the basis of "tube tone"
a lot of people will say that the power amp and output transformers have a large part in the tube amp sound.
i went from a genz shuttle to an all tube orange head and to me its a totally different feel and sound, for me the thousands of dollars more was worth it. others will chime in with better explanations than me.

[EAdanikDG]

Most have a gain, but that doesn't break up the tube preamp, from what i've seen anyway. If the gain does break up the tube amp, however does that mean there's no point in getting a R500 and that the LM Tube would do the same? (The LM Tube is a few hundred AU dollars cheaper.)

[tony_clifton]

All solid state/hybrid amps break up because of the preamp circuitry. Gain is as good as always preamp volume, master is volume to the cabs. You can't make a solid state power amp clip like a tube power amp because it would destroy the speakers.

What that advertisement said is that there is a tube in the preamp instead of a transistor and that it can break up and they call it a tube sound. Nothing more. As far as I have read over here even solid state markbass amps can do the SVT (tube) trick pretty good, so it's not really a must have feature.

Then we come to the point where the discussion escalates in 'preamp distortion is cheap and you need big trannies'. Something I want to steer clear from. I haven't 'expierenced' it myself, and for me the advantages of a (portable) hybrid outweigh true tube anyway.