Adventures in Fractal's Dual Rectifiers

[Orvillain]

This is quite cool.

Same settings as above:

Dual Recto Red Modern:
Bass - noon
Mid - 2 o'clock
Treble - 2 o'clock
Gain - 2 o'clock
Master - 9 o'clock
Presence - 3 o'clock
FX Loop Bypassed
Bold
Diode

But the load changes: and nothing else.
Red: Egnater Tourmaster 4x12 with V30's at 16ohms.
Green: Marshall JCM800 Lead 1960 with T75's at 16ohms.
Purple: Marshall Mode Four with K100's at 8ohms.
Light Blue: Suhr Reactive Load IR at 8ohms.
Yellow: DIY Loadbox (schematic unknown) at 16ohms.
Dark Blue: Small 1x12 fully open backed cab with a T75 in it at 16ohms.

The three real life cabs are all quite similar. The two loads however, are quite different from the cabs and from one another.

Zoomed in version:

 

[GTR37]

This is a great thread ,lots of great insight being shared and tips and tricks

Now do you think possibly we could get the Bogner 101b?
I know there are schematics avail and Austin Buddy on the Fractal forum has offered his up
We have at 20th Anni but IMO the 101b is that classic Bogner sound
Sorry for the detail but at least it’s Alice in chains

 

[Orvillain]

@FractalAudio @James Freeman

So I'm working on dialling in Recto2 to match up freq. response-wise with my real amp. And tbh, with a few small tweaks I can get it close.

Red is the real amp. Greenish is Recto2.

I don't really know how to improve the closeness of the 60-80hz range. To my ears, it is quite critical.

Things I've tweaked so far:

Preamp > low cut frequency at 10hz
Preamp > high cut frequency at 40khz
Speaker > Low freq at 117hz
Speaker > LF Reso at 7.9
Speaker > LF Q at 2.096
Speaker > High Reso at 7.29

 

[la szum]

This is quite cool.
View attachment 15472
Same settings as above:


But the load changes: and nothing else.
Red: Egnater Tourmaster 4x12 with V30's at 16ohms.
Green: Marshall JCM800 Lead 1960 with T75's at 16ohms.
Purple: Marshall Mode Four with K100's at 8ohms.
Light Blue: Suhr Reactive Load IR at 8ohms.
Yellow: DIY Loadbox (schematic unknown) at 16ohms.
Dark Blue: Small 1x12 fully open backed cab with a T75 in it at 16ohms.

The three real life cabs are all quite similar. The two loads however, are quite different from the cabs and from one another.

Zoomed in version:

View attachment 15473

Wow! That is massive!

So this means we should all literally stay the fuck away from Load Boxes because they suck ass and
turn amps into something they are not??

 

[la szum]

This is a great thread ,lots of great insight being shared and tips and tricks

Now do you think possibly we could get the Bogner 101b?
I know there are schematics avail and Austin Buddy on the Fractal forum has offered his up
We have at 20th Anni but IMO the 101b is that classic Bogner sound
Sorry for the detail but at least it’s Alice in chains

This is why I am passing on the 20th I could buy for a great price. I really had
my hearts set on a 101b all along.

 

[GTR37]

This is why I am passing on the 20th I could buy for a great price. I really had
my hearts set on a 101b all along.

the 20th is really nice , its just a bit different , more open but doesn't quite have that chew ( hate the word) in the Mids , the 101b just has that addictive Mids ,that IMO no other amps do , its the Bogner Thing

 

[Orvillain]

Wow! That is massive!

So this means we should all literally stay the fuck away from Load Boxes because they suck ass and
turn amps into something they are not??

Well I wouldn't quite say that. But they're definitely just approximations, and are missing a lot of subtle information that a real cab moving some air gives you.

 

[la szum]

I was told graphs don't lie. Was it you, @Orvillain ??

The LBs are not even in the same drinking district as the Cabs. They are like
all the way across town. Says the graphs.

 

[0XI0]

Wow! That is massive!

So this means we should all literally stay the fuck away from Load Boxes because they suck ass and
turn amps into something they are not??

if the amp uses negative feedback (damping) the really good load boxes made to replicate the SIC are great, not that far off from the emulated cab. For silent recording u can't beat the tone of a good load box vs just preamp into IR.

the problem with amps that don't use negative feedback (recto modern, AC30, no damping) is the SIC has a lot more effect on the output EQ, so compared to the right cab the load box is way off

with recto modern the mesa oversize V30 4x12 is supposed to be the intended output eq curve for the amp, the recto OS 4x12 cab is essentially equivalent to the Mark Graphic EQ scoop shape, but supposed to be dynamic as the cab and power amp push against each other. load boxes don't flex

 

[EOengineer]

That first post has me missing my old Rev G so hard right now. Acquiring a replacement is literally one of my 2024 goals on paper. That revision just sounds best to me. It rips and crunches in a way the newer ones don’t…and yeah…there’s a top end too.

One of the biggest mistakes Mesa ever made was to abandon the Rev G for anything beyond basically a Rev G with a better FX loop. Absolutely killer amp anyway.

 

[Whizzinby]

FAS Modern is instant chunk.

@Whizzinby have you tried FAS Brootalz?

I had tried it before but sort of quick scrolled it. I just spent about an hour playing the Brootz and it’s really great. I dropped the master down to about 1.5 and left everything else default, granted that takes a touch of brutalz out of it, but super punchy and crisp. I kept trying to add drives and input boosts almost out of reflex, but it totally doesn’t need anything unless you want that top end sizzle.

 

[riffy]

This is a great thread ,lots of great insight being shared and tips and tricks

Now do you think possibly we could get the Bogner 101b?
I know there are schematics avail and Austin Buddy on the Fractal forum has offered his up
We have at 20th Anni but IMO the 101b is that classic Bogner sound
Sorry for the detail but at least it’s Alice in chains

That sounds awesome!!!!! Love it!

 

[MirrorProfiles]

This is a great thread ,lots of great insight being shared and tips and tricks

Now do you think possibly we could get the Bogner 101b?
I know there are schematics avail and Austin Buddy on the Fractal forum has offered his up
We have at 20th Anni but IMO the 101b is that classic Bogner sound
Sorry for the detail but at least it’s Alice in chains

what’s the difference? or what can the 101b do that the 20th Anniversary can’t?

 

[GTR37]

what’s the difference? or what can the 101b do that the 20th Anniversary can’t?

it is a different circuit , the 20th was based on 6l6 but the bright switches are different , it has a more traditional Marshall Midrange vs the 101B
the 20th has a lot less gain on the blue channel, the biggest thing is the mids the 101b has more compression and squish and just feels incredible to play , the 20th is tighter out of the gate ,but the 101b is still tight enough for rock , if you go metal it boosts well too

 

[saarangnarayan]

But the FAS Modern version is turning me into a believer.

I thought Modern was a 5150-ish thing (and also Modern II), and Modern III was the Dual Rec thing?

 

[dean701]

Modern 1 is based off recto with tighter lows. Modern 2 is 5150ish

 

[dean701]

Amplifier models list - Fractal Audio Wiki

wiki.fractalaudio.com

 

[DLC86]

@FractalAudio I've already said it several times on Fractal forum, but I'll repeat it here one last time anyway:
A tool in axe-edit or cab-lab to let the users import their own SICs into the Axe/FMx would be a great step-up in terms of accuracy, especially for those of us who use a real cab and/or custom IRs, or those that like to make this kind of comparisons with real amps.

 

[SwirlyMaple]

@FractalAudio I've already said it several times on Fractal forum, but I'll repeat it here one last time anyway:
A tool in axe-edit or cab-lab to let the users import their own SICs into the Axe/FMx would be a great step-up in terms of accuracy, especially for those of us who use a real cab and/or custom IRs, or those that like to make this kind of comparisons with real amps.

That would be rad. For the serious IR vendors out there, it’d give them the ability to produce the dynamic component of cab response that no other modeler lets you adjust. Would get you even closer to the true sound of that cab with the amp model you’re using.

 

[MirrorProfiles]

i think the amp has a bright cap on the master too, there is a master bright cap in the model but it's not on by default. also the model bright cap defaults to 250, to my ears ~500 behaves way more like a stock dual rec

Had some time today to play around with this, and it makes a big difference to me as far as hearing what I'm looking for. Definitely more than the other parameters (lowering MV and speaker parameters as much as possible only goes so far). Quite hard to rely on Mesa schematics because they generally aren't accurate - what do we know about the bright caps used on Dual Rectifiers? which revisions have which values?

Ill try and open my amp up later to take a look.

If my amp does indeed have a bright cap on the MV, presumably the correct bright cap value for me will need to factor in the taper of the model. So rather than matching an accurate cap value, I'll need to compensate for the pot taper a bit