IRs made with SS amps or Tube amps?

[Michael R]

What if IR companies did this?
One cab, one mic and position....one SS amp and 8 variations of tube amps. All 4 major tube families with a V= Vintage and M= Modern variation.
For example: last word in name is what kind of amp was used, EL34V or EL34M or _SS
I made these, what do you think?
I find it adds about the same difference sort of like changing the Speaker Impedance curve.

 

[Michael R]

If anyone DLd that 1960AX cab above (I deleted it)....I will have to redo that one. I messed something up there and had a few of those out of alignment/phase.

 

[Michael R]

Here is a Bogner 412 with V30s to try. One SS and 8 tube variations, sm57 mic

 

[Michael R]

Here is an Orange 1x12 with a G12H30 Anniversary. Same as above, one SS and 8 tube variations, Telefunken SH-M81 mic

 

[Greg Ferguson]

one SS amp and 8 variations of tube amps

Huh?

Ok, how are you going to combine a solid state amp and eight different tube amp types? There’s a dichotomy afoot. Solid-state amps do not use tubes and we don’t make IRs of tube amps because they’re not neutral.

Beyond that, what you are talking about is basically the same idea as profiling, only, if it could actually work, it’s a snapshot of that amp and multiple tubes, under those exact conditions, only you have cluttered it up with the microphone. You can’t force that snapshot to be any other combination, in other words, if those tubes are cooking, totally saturated, like a great rock sound should, how are you going to get them to react like any other real tubes and amp would if you rolled back the guitar volume to 2? You can’t.

Instead, you do what Fractal has done, and mathematically model the behavior of the tubes in the preamp and amp and then take a neutral snapshot of the cabinet with specific speakers through a known microphone and apply that to the whole. If the preamp and amp models are pure, with given specific tubes, and the IR filters their sound, we can adjust the guitar, preamp or power amp and if the modeling is correct, the sound will replicate that preamp, power amp, tubes and cab.

 

[Aivoryuk]

Didn't Ownhammer do this with one the packs (studio essentials???) - that captured an IR with a SS and then the same mic but with a tube amp.

 

[Grindcrusher]

Solid-state amps do not use tubes and we don’t make IRs of tube amps because they’re not neutral.

If you liked the sound of the tube power-amp IR with your amp-sim, why wouldn't you use it?


I haven't had time to try the files linked above, but I have tried making IR's with solid state and tube amp myself. My mids are more scooped when I use the power amp of my rectifier, or Orange AD200 bass amp, compared to a solid state amp.

 

[Michael R]

Huh?

Ok, how are you going to combine a solid state amp and eight different tube amp types? There’s a dichotomy afoot. Solid-state amps do not use tubes and we don’t make IRs of tube amps because they’re not neutral.

Beyond that, what you are talking about is basically the same idea as profiling, only, if it could actually work, it’s a snapshot of that amp and multiple tubes, under those exact conditions, only you have cluttered it up with the microphone. You can’t force that snapshot to be any other combination, in other words, if those tubes are cooking, totally saturated, like a great rock sound should, how are you going to get them to react like any other real tubes and amp would if you rolled back the guitar volume to 2? You can’t.

Instead, you do what Fractal has done, and mathematically model the behavior of the tubes in the preamp and amp and then take a neutral snapshot of the cabinet with specific speakers through a known microphone and apply that to the whole. If the preamp and amp models are pure, with given specific tubes, and the IR filters their sound, we can adjust the guitar, preamp or power amp and if the modeling is correct, the sound will replicate that preamp, power amp, tubes and cab.

I'm sorry, I probably didn't state that well enough. In the files I posted above, each folder contains 9 individual IRs. Each IR is the same mic and cab but made with different power amps. The IR with the "_SS" at the end is the solid state version and the IR with the "_EL34M" is the version made with an EL34 Modern style power amp, etc. This is not modeling or capturing a power amp. It is simply making an IR with different power amps.
I am fully aware that there are people who say that you must make an IR with a SS amp. Which one? They all have their own frequency response. You could make 10 different IRs with 10 different SS amps and the result would be 10 different IRs that sound different. A tube amp will surely impart it's frequency response on the created IR. That is my point here. I believe if you want to use a specific IR that would/could work with any amp, then an IR made with a SS amp is probably best choice. The theory of using a neutral amp would apply here. But, if you are going for example, a Plexi type tone, it might be best to use an IR made with a vintage styled EL34 power amp. Let your ears be the judge.
In the AF, we can select between different impedance curves. What is that doing? Adding a resonant frequency which would align closer to the real deal. I will submit that using an IR made with the power amp which the modeled amp is using works kind of the same way and would add more to the realism of that tone. Would it be perfect? Absolutely not. Neither using an SS version either. Both ways have the same problem. An IR can not adjust to the differing db levels that a real amp would do to a speaker. In other words, shoot an IR with a very low signal to the cab and then compare it with one shot with a very high level. They will sound different because the speaker will react different depending on the volume. Now, when it comes to using a tube power amp there is a whole other thing to consider. What about how hard or soft you send that signal to the power amp?
Go light on that signal and it will sound thinner. Hit it harder and the frequency response will improve. Go too hard and the power amp will compress and flatten out.
I would submit that the best way to model/capture a tube amp would be to set the master or gain on a NMV amp to 1 then shoot an IR. Keep moving that volume up and shoot an IR of that cab on each step until you get to 10. Then, make the model use the correct IR at that specific level. The result would be much more accurate. Maybe you would name it a "Dynamic IR player" that chooses the IR depending on the volume of the amp?
I think many of the IR companies that have used tube power amps 1) don't say what amp was used. 2) probably are not paying enough attention to the volume they shot those IR at. What did I do here? I used a happy medium in which the frequency response is at it's largest with each tube amp being used.
Again, use your ears and not your internet eyes. DL those files and listen for your self.

 

[Michael R]

If you liked the sound of the tube power-amp IR with your amp-sim, why wouldn't you use it?


I haven't had time to try the files linked above, but I have tried making IR's with solid state and tube amp myself. My mids are more scooped when I use the power amp of my rectifier, or Orange AD200 bass amp, compared to a solid state amp.

Exactly!

 

[Grindcrusher]

All this is to the side, if you really wanted to make the amp have minimal impact of the final sound - is anyone using software to compensate for the amp? I know ML Sound mentioned this in his video about making great IRs and I'm wondering if REW would be a good tool for this.

By making a profile in REW you could use something like a Torpedo Captor to make a loop out of your DAW and through the amp and back in again. REW would then compensate for this when you make the sweeps.

My only question is how much the torpedo itself will colour the sound. The torpedo would be in the chain for the profile but not when you make the real IR.

I guess there's only one way to find out.

 

[Michael R]

Here is a vid of me showing the difference in sound between a SS IR to a few tube IRs of the exact same cab and mic position.

 

[FractalAudio]

All this is to the side, if you really wanted to make the amp have minimal impact of the final sound - is anyone using software to compensate for the amp? I know ML Sound mentioned this in his video about making great IRs and I'm wondering if REW would be a good tool for this.

By making a profile in REW you could use something like a Torpedo Captor to make a loop out of your DAW and through the amp and back in again. REW would then compensate for this when you make the sweeps.

My only question is how much the torpedo itself will colour the sound. The torpedo would be in the chain for the profile but not when you make the real IR.

I guess there's only one way to find out.

The Axe-Fx III can automatically compensate for the amp if you use the "Mic + DI" mode when capturing IRs.

Re. the OP. I fundamentally disagree with this approach but if you like the results that's all that matters. IMHO, an IR should only include the sound of the mic and speaker. The amp and mic preamp should be neutral.

 

[Michael R]

The Axe-Fx III can automatically compensate for the amp if you use the "Mic + DI" mode when capturing IRs.

Re. the OP. I fundamentally disagree with this approach but if you like the results that's all that matters. IMHO, an IR should only include the sound of the mic and speaker. The amp and mic preamp should be neutral.

Many years ago, lots of guys said Modeling was not the right way to do it Like I had said above, I liken it to "Speaker Impedance curve". It just adds that more to the realism of the tone, IMHO. Really, no different than adding an EQ to your tone. I like the EQ curve of a real tube power amp.

 

[yek]

Ownhammer provides or used to provide IRs created with a tube power amp.

 

[Michael R]

Here are those IRs in the above vid I posted.

 

[666was999]

Many years ago, lots of guys said Modeling was not the right way to do it Like I had said above, I liken it to "Speaker Impedance curve". It just adds that more to the realism of the tone, IMHO. Really, no different than adding an EQ to your tone. I like the EQ curve of a real tube power amp.

Besides EQing, poweramps also add compression. And since the poweramp only gets one tone at a time when running the sweep for the IR this is the compression a poweramp adds alike when playing single notes. The poweramp didn't get any chords from the sweep, so it wasn't compressing as much as when the supply had to take chords. But that means you actually can't catch everything of a poweramp, only a certain part. When you like it, that's good, but is it a sound method?

 

[Michael R]

Besides EQing, poweramps also add compression. And since the poweramp only gets one tone at a time when running the sweep for the IR this is the compression a poweramp adds alike when playing single notes. The poweramp didn't get any chords from the sweep, so it wasn't compressing as much as when the supply had to take chords. But that means you actually can't catch everything of a poweramp, only a certain part. When you like it, that's good, but is it a sound method?

If you read my looong post above I kind of go over this
You can take a DI box and place it between the power amp and the cab. Record that signal with your IR sweep. It does not matter which amp whether SS or tube you use. It will be different on each recording. All power amps will add their own color to the result. Obviously tube amps will add more and that's why we like tube amps, isn't it? Now use that same DI box and then use a tube amp and drive it real hard. The result will be that because of the compression that signal will flatten out and effectively be like the SS amp. So, like I mentioned above, the key to do it is hitting that tube power amp correctly. If the modelling amps are doing their job right by compressing at higher volumes then an IR done with the appropriate Tube amp will add the more correct frequency response, which a SS version will not.

 

[666was999]

If you read my looong post above I kind of go over this
You can take a DI box and place it between the power amp and the cab. Record that signal with your IR sweep. It does not matter which amp whether SS or tube you use. It will be different on each recording. All power amps will add their own color to the result. Obviously tube amps will add more and that's why we like tube amps, isn't it? Now use that same DI box and then use a tube amp and drive it real hard. The result will be that because of the compression that signal will flatten out and effectively be like the SS amp. So, like I mentioned above, the key to do it is hitting that tube power amp correctly. If the modelling amps are doing their job right by compressing at higher volumes then an IR done with the appropriate Tube amp will add the more correct frequency response, which a SS version will not.

I don't know if the curve gets more or less correct, however an IR is not just only the frequency response curve. There's also the magnitude/impact over time and the phase. A compressor changes the impact curve.
Now a comp baked in in the IR is not the same as a comp block in the chain with a plain IR. It isn't really working. The baked in comp got triggered by a sine sweep and does not react depending on the signal. An actual comp block in the grid gets triggered by the signal and is different.
So you just baked in something undefined, but you liked it.

 

[cole lewis]

The thing I would assume this is useful for in at least some way would be when you’re running a preamp pedal into IRs. A revv G4 or something.

The color from the tube poweramp could work really well there.

 

[Postretro]

I did try one of these IR's against my regular IR. Elements of the tube distortion were there. And the chug was definitely nicer and more pronounced. I am all for for adding harmonic complexity. But, the loss of clarity and definition was too much for me. It also seemed less organic and displaced. Perhaps, because it was used in a different evvironment than it was generated in.

My experience is that it isn't easy to add complexity with a general strategy that feels organic and has a sense that it was "meant to be." I feel the same way about Room IR's. There are elements I like. And yet, it feels foreign and out of place in other environments,

I remember when everybody said a post-PI master volume would never work because a dual pot would not have a matched resistance that was close enough.for a push-pull power amp.

Collective blind spots are all-around us and untouched,