Thank you so much, that is all I needed to know.
There is just one question remaining for me; for the power supply should I use a single 24V supply or a dual 12+12 supply? Because I'm gonna use the same supply rail for feeding the tube heaters.

Thanks again...
Sajad

Edit:
Besides here is the building diagram of what I have in mind: https://db.tt/G9a4Dfmm

Thanks man, I already have a High octane tube amp, but I found myself playing it at around TV level and the master volume doesn't pass 9 oclock!
So practically the output section doesn't color the sound and I get all the tone from the preamp!

Besides I have a diy combo cabinet around with a Celestion 8" 15W inside, so it may be fun to build  a tube preamp to get some triode tone and then feed into a pure clean SS power amp to take care of speaker driving, and maybe add a switchable PT2399 delay line before the output section in the case of lead...

I also tought about attenuating the signal to appropriate level for the chip amp, but looking at the 12ax7 plate curves, the signal level coming out of the preamp will be around 180V p-p! So I need a serious attenuation here...

I choosed 3.5V p-p because it is the max input headroom of PT2399. The problem with Chip amps is that they all have preamp section for voltage amplification too, so they all will clip very soon.
I wonder if there is a schematic for any ONLY power amp section for around 6-12W into 8 ohms?

I found these schematics but since I'm a total noob in the SS realm, maybe someone here can take a look at these schematics or maybe come out with a better idea  :
http://circuitswiring.com/fet-based-audio-power-amplifier-with-12w-output/
http://circuitswiring.com/12w-amplifier-circuit-based-741-op-amp/

Thanks

Hi guys, I'm planning on building a tube preamp/SS power amp style hybrid guitar amp.

The preamp section is basically from ax84 High-octane with tone stack:
http://www.ax84.com/hioctane/AX84_Hi-Octane_101004.pdf

After the preamp and tone stack I'm planning to use a fixed resistor divider in the place of MV to attenuate the signal level to around 3.5V p-p and feed it into an opamp buffer; something like this:
http://www.tremolo.pl/Przedwzmacniacze/JCM%20900%20Marshal.gif
I'm assuming the HV doesn't damage the opamp at start up, does it?

My main issue is the power amp; At first I was going to simply use a TDA20X0 chip, but it seems with a 12V+12V supply and 8 ohm speaker the input signal must be under 0.40V to avoid clipping.
So maybe I should build a discrete power amp section...
What's your opinion on this project?
Any help would be appreciated...

Thanks
Sajad

2N3819 is a nice replacement but with different pinout: D-G-S

Thanks alot, That's lots of helpfull information.

Thank you man, I've built a TDA chip amp before, but this time I wanted to avoid bipolars and build a complete FET amp. How about the signal's phase? Do I need the output phase to be the same as input's? Is it necessary for a guitar amp?

Hi guys, I'm new here, I was trying to build a FET-based practice amp and I found this:http://www.hawestv.com/amp_projects/amp_solid_tube/art_guitar_amp/2_IRF510adj_Dif_In.GIF
I modeled it with LTSpice with two stages of ROG Fetzer valve and I've got some interesting news:
Input signal of 100 mVhttp://i587.photobucket.com/albums/ss312/sajy_ho/FETInferno100mv-1.jpg?t=1388776143
Input signal of 300 mVhttp://i587.photobucket.com/albums/ss312/sajy_ho/FETInferno300mv-1.jpg?t=1388776150
The distortion characteristics is alot like tubes, but I'm wondering does the output sinal need to be in the same phase as the input signal or not? And what do you say about the circuit? Does have a worth of trying?
Thank you guys and sorry for terrible English :duh