Here is mine
Sound clips:
Ultra Sample.mp3 - Wet
Ultra Sample1.mp3 - Dry
Images of THE AMP

Thanks, yes it is super hi-gain, I like Marshall on steroids kind of amps :tu:

I repaired it, it should work now.
Ultra Sample1.mp3 - dry
Ultra Sample.mp3 - wet

Hi, you can use anything as a follower (what suits you the best), first use tubes, and if you like the sound let them in the circuit, as for SS followers you can use high voltage mosfets (with 100K bias and divider), or fet (supplying it from the PA supply).

Quote from: Brymus on August 17, 2009, 06:53:49 PM
I think you misunderstood my fault.
The idea was to go from the phase inverter in the Marshall to 2 X 3886 in bridged mode.
But instead of inverting one chip to get the inverted phase for BTL mode.
I would take it from the phase inverter of the Marshall 18 watt.
This ways both chips would be non-inverting.

Maybe better to use the signal before the PI and use the 3886 X 2 in normal BTL form?

Would the 3886 chips work?

And would the signal be TOO much for use as a pre amp to the 3886s as the plates are at
high V?

That's a different story,
try the boath ways, and see wich one suits you the best.
LM3886 will do the job, but you'll have to put voltage follower between preamp and PA, because phase inverter has hi out Z. Put 1M attenuator resistor in series with power amp input, as a  protection for your IC's.

Quote from: Brymus on August 17, 2009, 01:00:19 AM
WOW thats a really nice sounding amp indeed then.
Very nice job.
I was thinking of trying a hybrid too.
DId you still go with 4 gain stages -2 triodes?
I have 4 stage SE amp it is a Trainwreck Francesca pre with a Marshall stage .68uf 2k7 bypass in front of that,Very high gain I was considering using that in front of my LM3886 chip but read here 12ax7s not so good for use with the SS power amp.
After hearing yours I think the tone is incredible, exactly what I am after for the dirty channel.
I was also considering using my Marshall 18 watt pre-amp all the way to include the phase inverter -
Into two 3886 chips both non-inverting BTL,wouldnt this work as well?
That way the signal is already 180 off so both chips would be non-inverting.
Or is that too much?
The normal channel is both halves of triod in parallel the other is tremelo channel.
I would just have to adjust the power rail a little to keep the V down with  the PA not being used.Or just use a different transformer.

Thanks,
You see, you could do that, but I think you wont be happy with it.
First: your poweramp is LM3886 (super clean hi-fi powermp), I'm sure that BJT's wont give sound characteristics as MOSFET's, plus mine is little distorted in front end.
Secondly, if you put the preamp signals out of phase with each other they will cancel each other on the speakers and you'll get quiet dull sound.
Use two transformers, I wound mines by myself.
Tube trafnsformer:
Primary: 220VAC/50mA
Secondary:6.3VAC/4A

Quote from: Brymus on August 16, 2009, 03:49:34 PM
If that sound clip is just the amp and no pedals then I am BLOWN AWAY :tu:
Sounds crazy, good nice heavy tone.
Is it possible to translate your PDF to English?
Sorry I only know English and little Spanish.

Well, It was intend to be the Roccaforte preamp, but I didn't like the tone of that preamp, it was dull for my taste, and I completely redesigned it to suit my taste.
Yes, this clip is only amp, no pedals,compressor or any kind of boost,I only added slight reverb and little delay in the mix nothing else.Which thing's do I need to translate?

Hi guys,

I fixed the problem and here is the sample of my amp:
Ultra Sample.mp3
It was recorded with cheap PC mic.

Hi,
Phil, thank you for your replays, but I fixed the problems, now, amp is quiet as dead and it's lot of rocca in the tone. I just did the hi-fi trick (that mesa do too) put 6,3VAC on diode bridge, than on a large cap, and you get 6,3VDC, it works flawless.

I'll post some clips soon.

Quote from: phatt on August 05, 2009, 08:12:21 AM
Almost forgot! 
IF That tone stack is running directly to the TDA7294 then you need a high imp buffer stage otherwise you are wasting your tone stack, it will be hardly working. Phil.

Hi phatt, it's not the trainwreck it's Roccaforte HG100 (4 gain stages preamp):
Roccaforte Project.pdf

Well, I think it's problem with ground, as I'm turning the Master pot squiling and hum become less or opposite.
Actually tone stack is very responsive

Hi guys,
I made a hybrid amp. Roccaforte preamp and 100W MOSFET (TDA7294) SS amp.
I designed PCB (for the rocca and TDA):
Roccaforte Schematic & PCB.pdf
Some pics:







But I have a problem, I have noise and hum in the amp, here is sample:
Rocca Problem.mp3
and here is layout how i connected the amp,internally:
Rocca Layout.pdf

What can be the problem? Help me to solve this.

Hi,
it's like this in the SS power amps:
If you have 2xLM3886 which is about 140Watts of output, you'll need 1VA per watt of output.
So, 140Watts/0.85= 167(170Watts transformer)., You have 200VA*085=170Watts, which is perfect.

Bye.

More gain - 2N5484 FET's witch are hi gain(transductance) amplifiers
Better low end - Master Volume coupling cap is 100nF, output buffer coupling cap is 1uF not polarised cap(Wima).

Sorry, i can't give you the layout(I spent too much time on it), but you can make your own layout from picture.

Power supply is basic (200 power transformer, 2*4700uF power amp filter caps, lm317 regulated preamp supply.
Power amp is MOSFET TDA7294, all the information's you can find in datasheets, but I did minor changes.

That is basically it.