St.Rock ReactIR 2 now available! (frequency response graphs included)

...I shot the Suhr Reactive Load through the Behringer GI100 as that one has a low impedance balanced output which plays nicely with the Quad Cortex' balanced input:

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As I suspected, the worst part of the Suhr RL is the I/O section. Put through something just a smidge better, it looks great.
 
I reshot the sweeps with a louder sine signal (only attenuated by -30dB compared to -60dB in the first round of tests).

I "shot" the Suhr through the Behringer GI100 (tapped the signal from its XLR out instead of the Suhr) and via the DI port on the Suhr itself.
Graphs:
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Got to try out the attenuator feature. Got to test my Ceriatone King Kong 100W today in the apartment building I live in and through my Mesa 4x12 OS Straight cabinet so really put it through its paces.

The attenuator is simply awesome.

There is no perceivable tone-suck compared to running the amp straight into the cab. When I run it in Mode I (pushed in) the cab sounds / reacts much like it does with just the cab straight into the head. I know looking at the graphs I plotted that it ought to have about -2dB lowend but yeah.. can't tell when playing through the Mesa 4x12 OS Straight cab.

The "Attenuation" dial is completely usable throughout the entire range. The more you turn it clock-wise the louder it gets.

TBH it was one of the features I was least excited to try but now that I've taken it for a spin, I'm actually happy that I can play my amps through the cabs for a change instead of just routing them through my PC & headphones; there's just something to be said when you have that floor coupling effect /
#ampintheroom. :headbang
 
A quick sample vid with some noodling using the st.Rock React:IR 2's attenuator feature.



Signal chain:

Chinese Tele knock-off with SD Black Winter -> Ceriatone King Kong 100W -> st.Rock React:IR II attenuator -> Mesa Boogie 4x12 Oversized Straight cabinet

Captured with my Samsung S21 & my kids screaming in the background :pitchforks
 
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Couple of questions: I couldn't find a link to the manual on the St. Rock website... or perhaps it's so simple no manual is required?

I assume this works just fine with macOS and doesn't need drivers because it will simply appear as a USB audio device?
 
Couple of questions: I couldn't find a link to the manual on the St. Rock website... or perhaps it's so simple no manual is required?

I assume this works just fine with macOS and doesn't need drivers because it will simply appear as a USB audio device?
It's fairly straight-forward, yes. There was a quick-start / manual doc for the first revision - probably one'll come out for the newer one sometime soon.

As far as the app's concerned, you have to download the management app from app store https://apps.apple.com/us/app/reactirii/id6503413820 then just hook it up via USB or bluetooth.
 
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A quick sample vid with some noodling using the st.Rock React:IR 2's attenuator feature.



Signal chain:

Chinese Tele knock-off with SD Black Winter -> Ceriatone King Kong 100W -> st.Rock React:IR II attenuator -> Mesa Boogie 4x12 Oversized Straight cabinet

Captured with my Samsung S21 & my kids screaming in the background :pitchforks

awesome! To continue the conversation from my ox box thread, are the impedance curves like presets or do you make them yourself?
 
A

awesome! To continue the conversation from my ox box thread, are the impedance curves like presets or do you make them yourself?
The impedance curves are determined by the "Mode" switch on the front of the unit.
...you can get nerdy and if you have cab and are able to run some sweeps into its FX Return, you can use the "Tone Match" feature in the REACT:IR to create an adjustment IR (matching the React frequency response to your cabinet's), load that IR on the React:IR and voila... you now have an IR that adjusts the vanilla React:IR frequency response to the one of your cab. I did a few of those and loaded them on ToneHunt.org
 
A quick sample vid with some noodling using the st.Rock React:IR 2's attenuator feature.



Signal chain:

Chinese Tele knock-off with SD Black Winter -> Ceriatone King Kong 100W -> st.Rock React:IR II attenuator -> Mesa Boogie 4x12 Oversized Straight cabinet

Captured with my Samsung S21 & my kids screaming in the background :pitchforks


Sounds like Decapitated. Great band.

How does the impedance curve of the St Rock compare with the Suhr?
 
Sounds like Decapitated. Great band.

How does the impedance curve of the St Rock compare with the Suhr?
It is - Earth Scar :)
I listed some graphs in the earlier posts where you can see the React:IR II frequency response curve vs that of the Suhr and the 2 cabs you see in the vid
 
It is - Earth Scar :)
I listed some graphs in the earlier posts where you can see the React:IR II frequency response curve vs that of the Suhr and the 2 cabs you see in the vid

Wow, no idea how I missed those. Doh. Thanks though!

I'm still just a bit confused about the Suhr readings where one looks way off and the other looks more accurate. Are you saying you did the Suhr readings both direct and through a DI box? So the ones where the Suhr loses a ton of low end just [Suhr -> measuring device] while the one that looks more accurate is [Suhr -> DI box -> measuring device] ?
 
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Wow, no idea how I missed those. Doh. Thanks though!

I'm still just a bit confused about the Suhr readings where one looks way off and the other looks more accurate. Are you saying you did the Suhr readings both direct and through a DI box? So the ones where the Suhr loses a ton of low end just [Suhr -> measuring device] while the one that looks more accurate is [Suhr -> DI box -> measuring device] ?
Yeah... I found out the Suhr's output circuitry cuts lowend.
But when you put something like the Behringer GI-100 between the Suhr and the Amp and tap the Signal from that DI (Behringer GI-100 in my case) you bypass the output circuit of the Suhr and just use it's internal reactive load - the result speaks for itself.. a more satisfying lowend thump.
 
Yeah... I found out the Suhr's output circuitry cuts lowend.
But when you put something like the Behringer GI-100 between the Suhr and the Amp and tap the Signal from that DI (Behringer GI-100 in my case) you bypass the output circuit of the Suhr and just use it's internal reactive load - the result speaks for itself.. a more satisfying lowend thump.

Interesting. And just so i understand, you’re saying [Suhr unbalanced 1/4th inch DI out -> Behringer DI 1/4th inch input -> Behringer XLR out -> measuring device] correct?
 
Interesting. And just so i understand, you’re saying [Suhr unbalanced 1/4th inch DI out -> Behringer DI 1/4th inch input -> Behringer XLR out -> measuring device] correct?
Not quite:

Amp (speaker out socket) -> Behringer GI100 ( "INPUT" socket )
Suhr ("FROM AMP" socket) -> Behringer GI100 ( "DIRECT LINK TO CABINET" socket)

Then XLR from the Behringer GI100 into the audio interface.
 
Not quite:

Amp (speaker out socket) -> Behringer GI100 ( "INPUT" socket )
Suhr ("FROM AMP" socket) -> Behringer GI100 ( "DIRECT LINK TO CABINET" socket)

Then XLR from the Behringer GI100 into the audio interface.

Oh ok I see. You're basically using the Behringer to create an amp Line Out, tapped at the amp's speaker jack, using the Suhr as a dummy cab for its impedance curve.
 
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Here is the frequency response of the Red Seven Amp Central reactive load compared to the st.Rock React:IR 2.

Both loads were connected to the same tube amp (Ceriatone King Kong 100W) using the same settings / volumes.

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