Harsh Sounding Pre Amp(slo100 clone)

[anchovie]

I think we still need to confirm or rule out the possibility of grossly exceeding the power amp's input sensitivity. You said the power amp sounds great with a Metal Zone - where's the volume set at on the pedal? Does it start to sound bad if you crank the MT-2's level? Have you tried putting a large value resistor in series with the SLO master volume to heavily attenuate it and provide finer control over the lower volume range?

[slacker]

You could also try putting a buffer after the tone controls, no need to build anything just use a buffered pedal in bypass. The input impedance of the power amp is pretty low < 20k Ohms so it could do funny things to the frequency response of a typical tube amp style tone control.
It could just be that what you're hearing is what your preamp really sounds like though.

[DA-Drummer]

Had,t much time lately,
The Eq isn't the problem, beacuse it filters frequenties not the form of the signal.

You didn't say what kind of EQ is what you tried

Tone control is after te buffer, same as the Dual Rectifier, but (yet) without prescence control.

There is your answer.
And i dont think there is need for a higher order filter.

I think we still need to confirm or rule out the possibility of grossly exceeding the power amp's input sensitivity. You said the power amp sounds great with a Metal Zone - where's the volume set at on the pedal? Does it start to sound bad if you crank the MT-2's level? Have you tried putting a large value resistor in series with the SLO master volume to heavily attenuate it and provide finer control over the lower volume range?

The volume control is fine, just move the pot not to much around.

You could also try putting a buffer after the tone controls, no need to build anything just use a buffered pedal in bypass. The input impedance of the power amp is pretty low < 20k Ohms so it could do funny things to the frequency response of a typical tube amp style tone control.
It could just be that what you're hearing is what your preamp really sounds like though.

I maybe will try that buffer after tone control.

It could just be that what you're hearing is what your preamp really sounds like though.

And yes i realise it's maybe the slo100 clone that sounds that sharp, but diode clipping etc, sounded "sharp" so that's why i build a tube pre amp. But why can the tube amp than be sharper than a not Tube preamp

[zambo]

I would do the simple things first. try a bypassed buffered pedal into the power amp. should help some. Does the vox have a tube preamp? If so, putting a hot signal into it will just make the voxs tube warm up or distort a little.

[anchovie]

But why can the tube amp than be sharper than a not Tube preamp

Filters, EQ and the best pairing of preamp and power amp. There are many solid-state circuits that don't sound harsh thanks to good design.

Simply using tubes isn't a guarantee of smoothness, especially with SLOs and the like that are deliberately designed to produce a huge amount of clipping. When I go and see extreme metal bands blasting through Dual Rectifiers/5150s/etc, I rarely find myself thinking "hmm...nice warm tube sound"! 

[DA-Drummer]

Well that buffered pedal worked. it's still a bit sharp, but that doenst matter. I am goin to remove the IRF820 and sees waht it does then,
but first, how do i make a buffer?, i tried an BC549, with 12V collector and 10K on emitter, but there was no sound depending if i were playing or not, and sometimes it stopped. so my buffer didn't work.
This is the schematic i used: http://www.circuitstoday.com/wp-content/uploads/2011/11/voltage-follower-using-transistor.png

[anchovie]

That diagram isn't complete for this application as the input isn't biased to anything, which is why you're having trouble. Plenty of complete buffer circuits to choose from here: http://www.muzique.com/lab/buffers.htm

[DA-Drummer]

The bias is around 1.6 volts, but then i realised that the buffer i need is behind the tone stack