Reactive Loadboxes in 2023

tallcoolone said:
The only reason I found an issue with your post was that you stated something as fact that I do not find to be true at all:

I’ve run at least a dozen amps through the TAE that I know backwards and forwards. I assume Steve Stevens and Pete Thorn also are aware how their amps are supposed to sound and also are looking for load boxes that are “faithful to the real thing”. I’ve seen dozens of major acts with Ox boxes on stage. What you said is just wrong man.
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Faithful impedance curve is what I meant.
 
tallcoolone said:
Ahh….

….yeah I don’t know what that is haha
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It’s most easily understood by looking at the frequency plot of a speaker. Below is the plot of a greenback cab and v30 cab from the tgp thread linked earlier. These are 8 ohm cabs, see the ‘ohms’ on the right hand side of the scale.

6952FB99-D40C-4806-B67F-CBBFF28445B3.png

When you measure an 8 ohm speaker with a multimeter you read a dc resistance of about 7.5 ohms since that is measured at 0hz (DC). However the actual resistance varies quite dramatically at different frequencies. The big low peak around 100hz is the resonant frequency of the speaker cone (cab internal volume also influences what frequency it is at). The rising impedence from about 1000hz up is due to the inductance of the voice coil. Each speaker and enclosure will result in a slightly different curve (where the low peak is, how tall and wide, how much the high frequency increase, etc) but every speaker will have that same general shape. Compare to the plot of the various settings of TAE, which doesn’t represent a real speaker load.

Many older load boxes modeled the high frequency impedence only with no low peak. This is because getting the low resonant peak right is expensive, and requires a pretty specialised capacitor (big, bipolar, very low esr) and inductor (big, high current capacity, as close to zero dcr as possible, no saturation). Easier now as those parts have gotten easier to make and cheaper.

But regarding sound, does it matter? Some people still use hotplates and they sound good to them, and they are much further off. Answer is, it depends.

With my recto in modern mode, there is no negative feedback in the power amp (power amp is ‘undamped’), so the output of the amp follows the impedence curve (which is why recto’s in modern mode have huge bass and treble response). Any change to the load has a large effect on the sound. When I built my DIY load I put a switch on it that shorts the reactive element and turns it into a resistive load. I flip that switch and the recto goes from sounding very punchy and big, to sounding like a practice amp in a cardboard box.

However with my jet city jca50, which has much more power amp negative feedback, there is almost no difference I hear flipping between reactive and resistive. Though if I run the presence high, it’s more noticeable (since turning up presence and depth decreases power amp damping in the high and low frequencies, respectively).

A bit of negative feedback, which linearises the amp output and makes it more stable and less sensitive to the load, and differences between loads become less noticeable.

Thank you for reading my blog
 
mnemonic said:
It’s most easily understood by looking at the frequency plot of a speaker. Below is the plot of a greenback cab and v30 cab from the tgp thread linked earlier. These are 8 ohm cabs, see the ‘ohms’ on the right hand side of the scale.

View attachment 239105

When you measure an 8 ohm speaker with a multimeter you read a dc resistance of about 7.5 ohms since that is measured at 0hz (DC). However the actual resistance varies quite dramatically at different frequencies. The big low peak around 100hz is the resonant frequency of the speaker cone (cab internal volume also influences what frequency it is at). The rising impedence from about 1000hz up is due to the inductance of the voice coil. Each speaker and enclosure will result in a slightly different curve (where the low peak is, how tall and wide, how much the high frequency increase, etc) but every speaker will have that same general shape. Compare to the plot of the various settings of TAE, which doesn’t represent a real speaker load.

Many older load boxes modeled the high frequency impedence only with no low peak. This is because getting the low resonant peak right is expensive, and requires a pretty specialised capacitor (big, bipolar, very low esr) and inductor (big, high current capacity, as close to zero dcr as possible, no saturation). Easier now as those parts have gotten easier to make and cheaper.

But regarding sound, does it matter? Some people still use hotplates and they sound good to them, and they are much further off. Answer is, it depends.

With my recto in modern mode, there is no negative feedback in the power amp (power amp is ‘undamped’), so the output of the amp follows the impedence curve (which is why recto’s in modern mode have huge bass and treble response). Any change to the load has a large effect on the sound. When I built my DIY load I put a switch on it that shorts the reactive element and turns it into a resistive load. I flip that switch and the recto goes from sounding very punchy and big, to sounding like a practice amp in a cardboard box.

However with my jet city jca50, which has much more power amp negative feedback, there is almost no difference I hear flipping between reactive and resistive. Though if I run the presence high, it’s more noticeable (since turning up presence and depth decreases power amp damping in the high and low frequencies, respectively).

A bit of negative feedback, which linearises the amp output and makes it more stable and less sensitive to the load, and differences between loads become less noticeable.

Thank you for reading my blog
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It was a good blog.
 
For my silent recording workflow I just run a tube preamp into my interface and use an IR loader plugin. One less thing to worry about especially during longer sessions.
 
mnemonic said:
It’s most easily understood
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Apologies, I should have said, “I have no interest in knowing what that is”

Guitar box does what it says it does, better than the 14-18 other guitar boxes I’ve had. Plus it does a lot more than other boxes. Not surprised other guitar box manufacturers are trying to disparage it, it’s that good and kind of makes their boxes obsolete. Thorn has a freakin sig amp with Suhr lol
 
Aynirar27 said:
I haven’t used my Captor X as just a loadbox, I alway use it as an IR loader as well, but I have zero complaints. I haven’t A/B’d it with the real cabs, but it’s really easy to find really good sounds in it.
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For the last year and a half I've been basically running amps into the Captor X direct to a studio monitor, or PA when playing with the band. I've never been more pleased with my guitar sound.

I've also been running amps cranked into it the whole time basically. Suhr Badger 30 on Full Blast for 9 months, Laney GH50L similarly. Haven't had a questionable moment yet. An EVH 5150 Iconic I briefly had didn't sound that great through it, but I figure that its not really geared towards Poweramp based tone. Kind of flubby.
 
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mnemonic said:
It’s most easily understood by looking at the frequency plot of a speaker. Below is the plot of a greenback cab and v30 cab from the tgp thread linked earlier. These are 8 ohm cabs, see the ‘ohms’ on the right hand side of the scale.

View attachment 239105

When you measure an 8 ohm speaker with a multimeter you read a dc resistance of about 7.5 ohms since that is measured at 0hz (DC). However the actual resistance varies quite dramatically at different frequencies. The big low peak around 100hz is the resonant frequency of the speaker cone (cab internal volume also influences what frequency it is at). The rising impedence from about 1000hz up is due to the inductance of the voice coil. Each speaker and enclosure will result in a slightly different curve (where the low peak is, how tall and wide, how much the high frequency increase, etc) but every speaker will have that same general shape. Compare to the plot of the various settings of TAE, which doesn’t represent a real speaker load.

Many older load boxes modeled the high frequency impedence only with no low peak. This is because getting the low resonant peak right is expensive, and requires a pretty specialised capacitor (big, bipolar, very low esr) and inductor (big, high current capacity, as close to zero dcr as possible, no saturation). Easier now as those parts have gotten easier to make and cheaper.

But regarding sound, does it matter? Some people still use hotplates and they sound good to them, and they are much further off. Answer is, it depends.

With my recto in modern mode, there is no negative feedback in the power amp (power amp is ‘undamped’), so the output of the amp follows the impedence curve (which is why recto’s in modern mode have huge bass and treble response). Any change to the load has a large effect on the sound. When I built my DIY load I put a switch on it that shorts the reactive element and turns it into a resistive load. I flip that switch and the recto goes from sounding very punchy and big, to sounding like a practice amp in a cardboard box.

However with my jet city jca50, which has much more power amp negative feedback, there is almost no difference I hear flipping between reactive and resistive. Though if I run the presence high, it’s more noticeable (since turning up presence and depth decreases power amp damping in the high and low frequencies, respectively).

A bit of negative feedback, which linearises the amp output and makes it more stable and less sensitive to the load, and differences between loads become less noticeable.

Thank you for reading my blog
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This is an excellent post, should probably be a sticky. And forget blog, I think it could become a TED talk or a limited Netflix series.

tallcoolone said:
Ahh….

….yeah I don’t know what that is haha
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No worries man. First rule of having a disagreement with someone is to try and agree what the disagreement is about. Now that we know, there's actually no disagreement at all... and that's a win.
 
I have a PS2, a suhr RL and a Suhr RLIR, I want to get a Fractal Xload to compare. When I have compared the just the load in the PS-2 to the surh, I have preferred the suhr, just sounded clearer, but the PS2 load seemed to sound thicker with more lows.

I like to reamp with the suhr RLs and I added a high cut switch on the normal suhr RL, which is useful if you are using a tube power amp.
 
tallcoolone said:
The only reason I found an issue with your post was that you stated something as fact that I do not find to be true at all:

I’ve run at least a dozen amps through the TAE that I know backwards and forwards. I assume Steve Stevens and Pete Thorn also are aware how their amps are supposed to sound and also are looking for load boxes that are “faithful to the real thing”. I’ve seen dozens of major acts with Ox boxes on stage. What you said is just wrong man.
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He ain’t wrong in the least homie. I realize this was already squashed, but the speaker impedence is a huge, huge thing here. He’s not saying they sound “bad”, they just aren’t accurate. And they ARENT. PERIOD. Just because some of yiu don’t hear it or feel it doesn’t mean the rest of us don’t, especially those of us with great sounding rooms. Just because Steve Stevens used it, great. Do you have his FOH or his pro audio equipment? I don’t think so. The problems we Mortals have may not be issues someone like Steve Stevens has considering the arsenal of resources players like that have.


They aren’t accurate. The driftwood and st rock is the only ones even close, and even then, the way they react with an amps poweramp compared to a cab is STILL off.
 
I’ve owned most of them, and played through almost all except the redseven.

St rock is the best… but I have no idea what his current situation is being in Ukraine. I’d follow that with the driftwood. Closely behind that is Suhr. Waza is okay, I can understand people being skeptical of it though.

Stay away from two notes and UAD ox. I say this as someone who is very big on UAD plug-ins but the ox box should be a 400 dollar unit, if that. The impedance curve DOES make a difference.
 
VESmedic said:
And they ARENT. PERIOD.
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I disagree. You are welcome to disagree with me, I’m just a guy who has been playing for 30+ years and uses the thing every day.

I don’t throw my opinion out there about gear I have zero experience with. Those opinions aren’t worth much at all IMO/IME
 
tallcoolone said:
I disagree. You are welcome to disagree with me, I’m just a guy who has been playing for 30+ years and uses the thing every day.

I don’t throw my opinion out there about gear I have zero experience with. Those opinions aren’t worth much at all IMO/IME
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I don’t think either zen or myself are throwing around opinions on gear we haven’t used extensively, I can assure you of that. Like I said, maybe you don’t get what we are talking about here and that’s totally fine, but below 200hz, these things fail big time.
 
VESmedic said:
I don’t think either zen or myself are throwing around opinions on gear we haven’t used extensively, I can assure you of that. Like I said, maybe you don’t get what we are talking about here and that’s totally fine, but below 200hz, these things fail big time.
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All I care about—repeat, ALL I care about—is if it works the way it should and my amps sound and feel the way they are supposed to. After over 5yrs of daily testing, I have come to the conclusion that this box does and my amps do. Not sure what the issue is here—don’t use the thing if you don’t want. I promise you I will lose no sleep.
 
tallcoolone said:
All I care about—repeat, ALL I care about—is if it works the way it should and my amps sound and feel the way they are supposed to. After over 5yrs of daily testing, I have come to the conclusion that this box does and my amps do. Not sure what the issue is here—don’t use the thing if you don’t want. I promise you I will lose no sleep.
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The issue is that you straight up argued with zen about something you admitted you know absolutely nothing about, instead of just listening for a second. He IS right, and I get “all you care about” is if it sounds and feels like your amps with a cab, but just because you don’t get what zen is explaining, doesn’t mean he’s wrong in the least; because he isn’t. That’s the problem.
 
VESmedic said:
The issue is that you straight up argued with zen about something you admitted you know absolutely nothing about, instead of just listening for a second. He IS right, and I get “all you care about” is if it sounds and feels like your amps with a cab, but just because you don’t get what zen is explaining, doesn’t mean he’s wrong in the least; because he isn’t. That’s the problem.
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We've already moved past that my man--it wasn't an argument, I disagreed with a statement he made, explained my position and he clarified:
ZEN Amps said:
No worries man. First rule of having a disagreement with someone is to try and agree what the disagreement is about. Now that we know, there's actually no disagreement at all... and that's a win.
Click to expand...
 
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