Reactive vs Resistive loads (Clips inside)

[TheWinterSnow]

So in my loadbox thread there has been the question of reactive loads vs resistive loads. Becuase the my loadboxes have a cabinet out and still act as I DI, I did a quick mix of when the amp (5150) was loaded by a cabinet and when it was loaded by the resistive load in the loadbox.

I won't reveal which is which, but I will say that all the clips are unprocessed.

Solo'd the clips are pretty drastic, however, they are hard to distinguish in the mix. You can tell they sound different, but one doesn't necessarily stick out as better.

Mix:

A:https://dl.dropbox.com/u/1170463/Loadbox Demos/A.mp3
B:https://dl.dropbox.com/u/1170463/Loadbox Demos/B.mp3

Solo:

A:https://dl.dropbox.com/u/1170463/Loadbox Demos/A Solo.mp3
B:https://dl.dropbox.com/u/1170463/Loadbox Demos/B Solo.mp3

Its a blind test, guess which one is which

 

[viralz]

B sounds chunkier but A sounds clearer.

 

[TRUIE]

To me B sounds harsher, thiner, and more "static".
A sounds way more natural and "moves" better.
I voted A.

Nice test by the way, as I still plan on buying your loadbox but only for the DI part, with a reactive load behind (TubeTown Tonehound).
Of course I'll compare both techniques too (and if your loadbox sounds better on its own, I'll sell my Tonehound ).
Still broke as fuck too, so I'll have to wait... but I saw you're still improving your loadbox, so it's all good !

 

[TRUIE]

Oh and I only listened to the solo'ed guitars.
But fuck... now I listen again, and B seems better to me !
The low end sounds more "real" on the palm mutes.
I think the more prominent hi end on B fooled me the first time...

Anyway, I'm listening on cheap headphones so it doesn't help at all.
But now, I think that B "moves" better than A wich sounds much static to me...

I think B is the real cab load, and A is the loadbox

 

[PD-Baraka]

i like b the most, i has more depth.

 

[AceFireForce117]

B is the real cab for me. much better low end, even though a tad too chunky for me they sound better IMO

 

[prayfordarkness]

I think B might be the cab load, but as far as which I prefer? I voted A.
B has some flub that I would HP out, until I get something closer to A.

 

[Clark Kent]

This reminds me of the difference between Axe-Fx and real amps. The A would be the Axe and B the real amp in that.

I actually prefer the A in the mix but soloed the B had a cool low end. Too bad that low end didn't work that well in the mix.

 

[existencedenied]

I think B might be the cab load, but as far as which I prefer? I voted A.
B has some flub that I would HP out, until I get something closer to A.

this is pretty much how I feel, but I slightly prefer B. both tones have aspects that I like.

 

[FIXXXER]

A, mix and solo

 

[TheWinterSnow]

So The results are:

A: Resistive Load
B: Cabinet (Reactive) Load

Most of you guys nailed it on the head though, the real cabinet is a bit more dynamic mostly in the low end which is the result of speaker resonance. There is some more high end in there as well but it comes across as more of a linear boost where the low is more dynamic to playing.

 

[Axonic Rot]

I'm glad to see that someone did this test. Really cool.

 

[aortizjr]

Very interesting test!

I think that THD and the Powerbrake use a fan as a reactive load. The Weber MASS uses a speaker motor.

Adding something like that to your load box would up the price, but I thought the cab tone was better. I liked it so much better in fact, I think I will be trading in my reactive load box for a MASS to compare with my THD. I need two for silently tracking two guitars live.

 

[ArthurD]

B

 

[TheWinterSnow]

I think that THD and the Powerbrake use a fan as a reactive load. The Weber MASS uses a speaker motor.

The hard part is finding a 120W 45Vrms capable fan with similar frequency reactance to a real speaker. I would do it if I can find something of the sort for relatively cheap.

 

[hsnyder]

Indeed thank you for doing this indeed! Very interesting. Just had a thought - maybe someone should make a load kind of like weber's but with a spring attached to simulate the effect that the air pressure of a closed back cab would have... I may have to do this - that would probably be the most accurate load practical...

 

[TheWinterSnow]

Indeed thank you for doing this indeed! Very interesting. Just had a thought - maybe someone should make a load kind of like weber's but with a spring attached to simulate the effect that the air pressure of a closed back cab would have... I may have to do this - that would probably be the most accurate load practical...

The big effect in a real load is that you have speaker resonance (something that we should simulate as I have mentioned) and a 6dB/octave high shelf boost. Then the saturation design in my loadboxes takes into account the air pressure and flux variation non-linear characteristics. So for the most part, I think a software plugin could recreate the sounds of a reactive load when a restiveness load is being used. Again I could imagine that it would be cheaper.

You are right though, the Webber Speaker Motor does not simulate air pressure compression in a closed cabinet and its effects on the load and how the amp reacts to it.

I could imagine that writing software to simulate this would be cheaper than coming up with mechanical prototypes which could be physically impossible to recreate. Just my .02

 

[hsnyder]

The big effect in a real load is that you have speaker resonance (something that we should simulate as I have mentioned) and a 6dB/octave high shelf boost. Then the saturation design in my loadboxes takes into account the air pressure and flux variation non-linear characteristics. So for the most part, I think a software plugin could recreate the sounds of a reactive load when a restiveness load is being used. Again I could imagine that it would be cheaper.

You are right though, the Webber Speaker Motor does not simulate air pressure compression in a closed cabinet and its effects on the load and how the amp reacts to it.

I could imagine that writing software to simulate this would be cheaper than coming up with mechanical prototypes which could be physically impossible to recreate. Just my .02

But if the load WERE a speaker with a ripped out cone (magnet, spider, voice coil basically) then the resonance, flux variation, etc would be there. The main thing that wouldn't be would be the effect of the cab being closed back (ie the restoring force of the air in the cab). Also I just did the math and the relationship for air compression isn't linear as it would be with a spring. I'm about to do a first order taylor polynomial and integral remainder and find out exactly HOW non-linear. My guess is that for the distances we're talking about (delta x I mean), the error is extremely small.

Keep in mind, we're just talking about the load here. At that point, it would be software's job to recreate the frequency response of the speaker, and speaker distortion.

But again, this is just another idea... I agree that it could be done with software as well.

 

[polifemo]

my loadboxes have a cabinet out and still act as a DI

I wasn´t aware of this, but I did a quick test and the reactive/speaker load doesn´t only sound better, it feels better as well!
More alive and touch sensitive somehow.

I´ll do some EQ matching to get closer to the tone of the reactive/speaker load, as the resistive load sounds a bit hollow.

Cool feature though, as it is possible to do some low volume (home studio) recording using the loadbox as a DI when going thru the speaker cab. (Takes care of some monitoring issues compared to using a mic)

 

[hsnyder]

Well I just got a free SUNN O))) 8 ohm speaker with a ripped cone, so I'm going to try what I mentioned above, and compare to a power resistor and to the Palmer PDI-03 which is inductive but not dynamic.