[SOLVED] Amp + reactive loadbox + IR'S

andres6505

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Hey guys 👋
Need a bit of help here. I’m running a Peavey 6505+ 112 tube amp into a loadbox with a line out, going straight into an SSL2 interface.
When I run it through different IRs, I always have to EQ pretty hard with a low shelf and a high shelf to make it sound nicer—especially on the low end. Is it normal for the amp or the loadbox to behave like this?
I already checked the cables and everything’s fine. When I noticed the issue, I did some digging and found the speaker impedance curve Fractal uses on their sims. I copied that EQ curve and it actually improved the tone.
So my question is: do you guys EQ before or after the cab when running amps with IRs?
I’ll upload a clip or audio soon so you can hear what I mean. 🎸🔥

Sorry if I'm in the wrong thread
 

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What load box are you using? The impedance curve is not an EQ curve, it’s how the impedance the poweramp see’s changes with frequency.

With some load boxes, boosting in a similar way with eq can definitely help. Decent load boxes don’t really need that much correction to sound close to a cab
 
What load box are you using? The impedance curve is not an EQ curve, it’s how the impedance the poweramp see’s changes with frequency.

With some load boxes, boosting in a similar way with eq can definitely help. Decent load boxes don’t really need that much correction to sound close to a cab
Hi
I don’t have much info, but here’s a video of a well-known amp 👉 Toroamos.loadbox. go to minute 2:11.
Thank you for the clarification on the curve. The spot where I really need to push it is around 100Hz — I can end up adding almost 5 to 7 dB depending on the IR.
About the loadbox: in one of the videos they mention it’s reactive and even show an image of the impedance curve.
What I can tell you is that its line out is around 150–200 kΩ. I’ve tried it on the SSL2 in Line mode, and the tone feels more open with brighter highs. On Hi-Z though, it sounds more balanced, with the lows standing out a bit more.
Other than that, I’m not really sure 🤷‍♂️.
Maybe the amp or the tubes are acting up.
 
Maybe that's the problem but i go to upload a video hold on
If its amp in the room sound, thats your problem.

Using a load box with IRs and Montitors is the equivalent of listening to a Mic'd up amp in another through the control room console, or in fact the "sound on the album".

Which is totally valid, the sounds in my head are mostly album sounds.

In any case, those sounds almost always have some amount if EQ applied to them.
 
Hi
I don’t have much info, but here’s a video of a well-known amp 👉 Toroamos.loadbox. go to minute 2:11.
Thank you for the clarification on the curve. The spot where I really need to push it is around 100Hz — I can end up adding almost 5 to 7 dB depending on the IR.
About the loadbox: in one of the videos they mention it’s reactive and even show an image of the impedance curve.
What I can tell you is that its line out is around 150–200 kΩ. I’ve tried it on the SSL2 in Line mode, and the tone feels more open with brighter highs. On Hi-Z though, it sounds more balanced, with the lows standing out a bit more.
Other than that, I’m not really sure 🤷‍♂️.
Maybe the amp or the tubes are acting up.
A lot of reactive load boxes don’t quite have enough of a resonant bass peak, nor enough of a treble lift. The Driftwood load boxes for example was miles off an actual 4x12. The Suhr and Fractal boxes get much closer but still aren’t quite exact.

Really you’ll just have to isolate the variables and work out what’s going on step by step
 
here an update
- Hello, sorry for the delay and thank you very much for responding.

- I couldn't record with OBS, but here's an audio file only lead channel amp. I'll try again another day; I need to reinstall Windows.
- I've noticed that the rhythm channel (crunch) sounds amazing! Lots of bass and a more organic distortion, maybe it's a tube...
- Chain: tubescreamer->amp->loadbox->interface

- Don't worry about the post; I usually use it between 2-4.

https://www.dropbox.com/scl/fi/d8ih...ey=0pjb3b3nlabwa2072wrpm1yc8&st=j4x1k19c&dl=0

amp.jpg
 
here an update
- Hello, sorry for the delay and thank you very much for responding.

- I couldn't record with OBS, but here's an audio file only lead channel amp. I'll try again another day; I need to reinstall Windows.
- I've noticed that the rhythm channel (crunch) sounds amazing! Lots of bass and a more organic distortion, maybe it's a tube...
- Chain: tubescreamer->amp->loadbox->interface

- Don't worry about the post; I usually use it between 2-4.

https://www.dropbox.com/scl/fi/d8ih...ey=0pjb3b3nlabwa2072wrpm1yc8&st=j4x1k19c&dl=0

View attachment 52340

That almost sounds like it's blending the direct signal from the load box and an IR, when it should only be the IR. That bright, fizzy sound is exactly what a preamp sounds like when not going through a cab/speaker sim.

What's the routing in the AxeFX look like?
 
That almost sounds like it's blending the direct signal from the load box and an IR, when it should only be the IR. That bright, fizzy sound is exactly what a preamp sounds like when not going through a cab/speaker sim.

What's the routing in the AxeFX look like?
- the audio is just the direct sound from the amp going through the load box. The chain is simple:
guitar -> tubescreamer -> 6505+combo (no speaker conected) -> load box -> interface -> cubase -> no cab.
I shared it so you could hear the amp directly.
- its not a multiefect
- So I always equalize around 80-110 Hz with peak EQ with a very high Q so that it focuses only on certain frequencies, as in the image I uploaded in the first post. I add 4 to 10 dB depending on the IR. In the high frequencies, not so much, maybe 2 to 4 dB highshelf around 1-3 kHz or a few dB at 8 kHz with normal peak Q.
 
- the audio is just the direct sound from the amp going through the load box. The chain is simple:
guitar -> tubescreamer -> 6505+combo (no speaker conected) -> load box -> interface -> cubase -> no cab.
I shared it so you could hear the amp directly.
- its not a multiefect
- So I always equalize around 80-110 Hz with peak EQ with a very high Q so that it focuses only on certain frequencies, as in the image I uploaded in the first post. I add 4 to 10 dB depending on the IR. In the high frequencies, not so much, maybe 2 to 4 dB highshelf around 1-3 kHz or a few dB at 8 kHz with normal peak Q.
Post a clip with a cab sim. The one you posted sounds pretty horrid and somehow weird to me like there's something wrong with it.
 
Post a clip with a cab sim. The one you posted sounds pretty horrid and somehow weird to me like there's something wrong with it.
hi!, I forgot to mention that the audio I posted was for you to try with your own IRs. Now, if you put in an IR and it sounds awful, that's the opinion I need to have about what I said in the first post.
 
hi!, I forgot to mention that the audio I posted was for you to try with your own IRs. Now, if you put in an IR and it sounds awful, that's the opinion I need to have about what I said in the first post.
I think it would be useful to have yours for comparison.

In any case I gave it a spin and threw ML Sound Lab MIKKO 2 at it. Your clip is so aggressively midrangy in the 1 - 2.2 KHz region that I wanted to pick cabs and mics that would counter that, and apply some EQ.

I don't think it needs any impedance curve stuff at all.
 
I think it would be useful to have yours for comparison.

In any case I gave it a spin and threw ML Sound Lab MIKKO 2 at it. Your clip is so aggressively midrangy in the 1 - 2.2 KHz region that I wanted to pick cabs and mics that would counter that, and apply some EQ.

I don't think it needs any impedance curve stuff at all.
Yes I have tried a lot of IR's, and I agree with you, the mids are very pronounced, but that is common in peaveys, right?
That's why I always EQ in a V shape.
And as you can see in the amp picture the resonance knob is at maximum, and the low knob in the 7 position has more bass than in 10.
I think maybe its a tube problems...

Thanks for taking the time to give me your opinion.
 
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