Quality of line out in load boxes (iron man mini 2 & suhr reactive load)

[Guitarking]

Hi everyone,

Bought a Tone King Iron Man 2 mini. The attenuation is really fantastic! But not sure about the line out. Sounds dull to me. Anyone has the same experience?

So I'm using the line out of my trusty THD hotplate, which I think is much better (and adjustable). I have the speaker out of the hotplate into the iron man, and then the iron man on load. This also does something with the line out of the hotplate. Is this normal?

So what happens? What if one wants a full load (no speaker) but a great line out (without the load coloring the line out). How to do? Is this where the Suhr Reactive Load really shines (because all it does is being a load)?

[ef37a]

The whole area of guitar amp load boxes/power soaks etc is a minefield of subjective opinion. Heck! Peeps can't even agree on a good amplifier sound, complicate that with a 'not a loudspeaker' load and throw in various capacitors, resistors and maybe a few Henries and all opinionated hell breaks loose.

I do not have much direct experience of load boxes, have dabbled with some DIY devices a few years ago but since the combinations of amp make, model, power, bias type vary who does? One chap that knows more than most is ICBM over at the <thefretboard.co.uk> forum. He has tried several (but by no means all!) power soaks and loads on various amplifiers and has some conclusions. IIRC he favours partly 'inductive' loads on Marshall amps and totally resistive ones on others. Fenders perhaps?

The line outputs can be of two broad type. Flat where no fixed EQ is applied and 'speaker emulating' where an attempt is made to mimic the response of a guitar speaker. One of the properties of such speakers is that they have a very limited HF response, some start to dive as low as 5kHz and most are good 10dB down ref 1kHz at 10kHz. An A/B test with such a load's line out compared to a DI signal say from the guitar will sound dull. So, yer pays yer money and ....

Couple of thi9ngs to be wary of. The power rating of such loads should be viewed with the greatest suspicion. Something rated at 50W should not IMO be used with a '50W' valve amplifier since most of them can put out well over the book rating, some over twice that and you do NOT want a load to burn out and go O/C on a valve amp at full chat!

Do not use such loads on transistorized amplifiers. There is no point anyway because they almost all sound total **** if overdriven and there is a very good chance of the amp being destroyed, especially if an early design.

There will no doubt be come back on my opinions and I bow to anyone who has done some SYSTEMATIC testing but the combinations of load and amplifier types is so vast all one can really do is suck it and see.

Dave.

[Wonks]

You'll get the sound that's built into the load box, not your amps speaker sound and as ef37a says, that sound can vary a lot depending on what the designer sees as an amp sound.

The Tone King has one basic sound which you can tweak with the presence control.

The Hot Plate is quite similar in that you get one basic sound with hi and lo eq switches.

But something like the Two Notes Torpedo Captor X is a load box (up to 100W input) with downloadable cab and mic impulse responses, so it can sound like almost any speaker/mic combo you can think of.

https://www.two-notes.com/en/torpedo-se ... -captor-x/

Max (Studio Support Gnome) has one and loves it. And if Max says it's good, then it will be! Of course your opinion may vary, but he uses it for his Facebook live noodling sessions and it does sound very good indeed, as Hugh Robjohns and Martin Walker should be able to testify.

Certainly one to check out if you are looking for a pure load box. The other Torpedo products are also highly rated.

The UAD OX is another highly rated load box with cabinet emulations, and used by a lot of pros. https://www.uaudio.com/hardware/ox.html

If you want attenuation of a full load box with great DI sounds, then you will probably be best with this sort of product, part hardware, part software, that lets you get exactly the sound you want, rather than the limited choice you get for hardware-only units.

But you do pay a lot more for them.

[Guitarking]

Thanks!

Just to give some more info. I need a clean di signal to use with IRs in my Daw.

[Wonks]

Clean at what stage of the guitar signal? What IRs? Loads of different types of IR, so a bit more explanation of just what you want to do would be helpful.

[Guitarking]

I need the di signal from after the amp's output (so it encompasses all stages from the amp). In my daw i will use my own ir (impulse response) to fake a speaker.

My hotplate has a "clean"(=not dull) sound and works well with my ir when at 0dB attenuation (so i guess the signal from amp goes straight to speaker and hotplate only acts as a line out).
The Iron Man has a much duller sound at all settings wh
Both are advertised being line out signal. Also when i turn my hotplate to load the sound dulls too.

So im looking for why this happens (curious) and im looking for a load (100% attenuation) with the not dulled line out of the hotplate.

[Wonks]

OK, ‘line out’ only refers to the signal level of the provided output. It’s down to the load box maker to determine and describe what the line out signal’s function is.

Before software modelling and IRs came along, you wouldn't want a straight amp signal copy from a 100% load box. You'd want a signal that emulated a miked-up speaker signal, so you'd have a filter network that added quite a steep HF roll-off between 5kHz and 6kHz.

Even now, most load boxes provide a speaker-emulated signal. This will definitely sound 'dull' compared to the straight low level amp signal.

So you need a load box that can switch off the speaker emulation. I don't know the load boxes well enough to say which ones can do this and which ones can't, and I'm sure you're just as capable as looking up the specs as I am. But I'd have thought that the ones with software IR modelling built in would have 'none' options for the speaker, cab, and mic IR slots, so that you'd then get a full range amp out signal.

Also, most passive DI boxes have a -40dB switch allowing the DI box to be placed in line between an amp and speaker (or amp and loadbox), which will always give you the straight signal at a mic-level output. What I don't know is at what sort of amp power levels it's safe to do this at. It may be fine all the way up to around 100W of input power. Hopefully someone else will chip in on that.

[BigRedX]

I've always seen load boxes/power soaks as completely separate from DI and amp/speaker emulation.

The big problem with devices that do both is that while the speaker attenuation is always good at the very worst, the DI signal, even with speaker emulation, often bears no relationship to the sound of the speaker/cab that it is replacing. And unless you have a combo with DI speaker emulation built-in, the manufacturer of the DI has no way of knowing exactly what amp and cab sound you need to replicate.

While some of the better units will have multiple cab options that is still no guarantee that any of them will be the right one for you.

[ef37a]

I think Wonks has the best solution. Just put a load box on the amp and use a DI box that can handle speaker levels afore it. This Art unit seems ideal,
https://artproaudio.com/framework/uploa ... 6_V1.3.pdf Ok, it is a dual DI but it took me long enough to track THAT down!

The DI part can handle at least +18dBu and 'worse case' 100W into a 16R speaker is 40V rms* so a 40db attenuator is going to chop that to 0.4V rms (-8dBV) and so no problem.

* 56V peak and remembering what i said about valve amps when you really stick it to them? Could be a lot higher but ART gear has a very good rep and I doubt there would be a problem in practice. A lower speaker Z will of course give a lower voltage at 100W, only 20V at 4R.

And! IF you put a continuos 100W+ into any load that tin is going to get bloody hot!

Dave.

[Guitarking]

Thanks!

Just a silly question: putting a di in between amp and load, will the amp still see the load? I figure i use the thru so its like the signal goes straight to load and im only tapping of the ljne out signal?

My loudest amp is 32 watts by the way

[Guitarking]

Whilr were at it: another silky question. Can an active di be used? I gave a bss ar133 di.

[Guitarking]

Tried the BSS AR133 active DI. Seems to work. But, even now, there's a difference in clarity when my Iron Man 2 mini is on load or when it's on 0 attenuation. In the latter, it sounds (with a home made IR of the exact same cab and mic) quite identical to the live miced up cab, whereas in the former the sound is somewhat dulled. So apparently, a load still changes the sound of the di?
The question also is: would a different load, say Suhr Reactive Load or a Torpedo Cap 8 ohm react differenty?

[Wonks]

You've answered your first two questions. Yes, the amp will still see the load, and an active DI box will work if it's one with a -40dB pad on it.

A valve amp interacts with the load it's driving, so you'll get a slightly different output signal from the amp just by changing the speaker used, say from a Celestion Vintage 30 to a G12T-75.

Some speaker attenuator/load boxes are entirely resistive, which will result in quite a different signal coming from the amp than a 'reactive' one that uses inductors and capacitors to try and more accurately represent a speaker's varying impedance characteristics at different frequencies.

This is always going to be a compromise with a speaker attached, and even pure 'reactive' load boxes will give a slightly different sound from the amp.

As all the different load or attenuator boxes have different circuits, it's very likely that a DI box sampling an amp first running into a Suhr Reactive Load and then a Torpedo Cap 8 ohm will sound a bit different.

But what does it sound like passed through the speaker and cab IRs? As these will roll off most of the high frequencies giving the 'bright' sound you get coming direct from the amp, the end results may be very similar, nothing a touch of EQ won't fix. It's not something I've done, so I really don't know.

[hotlegs]

Yes, it really sounds dull. I wrote an Email to support and they told me, this is normal. I play an slo-30, this amp has a line out at the end of the output transformer (speaker side). Taking the ironman as a load and comparing ironman line out vs slo-30 line out, ironman sounds like an old Tapedeck of the sixties. Today I got my fractal x-load, sounds same like slo-30 line out. Now I use the ironman only as power-soak for Appartement level, this works. For recording my Fender amps or my SLO, I use the fractal unit. For SLO I can also use the SLO lineout with x-load or speaker connected. Ironman has obviously an error by design with the line out.

Michael

[Guitarking]

One would start to think there is a cab sim on the Iron Man line out...

[hotlegs]

No, no cab sim. Go to your DAW and listen with no impulse response, it sounds awful. I think it's only bad design, it kills highs and shape the bass a little bit. I think it's not ok, you have to turn to much to compensate in the DAW. For recording, I use another load.

[Wonks]

Yes, it has already been mentioned a couple of times that a lot of these load boxes have a line out with a speaker emulation, which is often not switchable. All these units are slightly different to each other in what they provide.

It is not a design fault, it is a design choice. Some of the manufacturers could be clearer about what the line out is, and whether it has a speaker emulation or not, but a lot do explain it in their manuals.

It does help to read the manuals in advance before purchase, to know as much about the unit as you can.

I don’t claim that these units have great speaker emulations (it’s often just a couple of capacitors and a few resistors), so some will sound better than others. But at sone point the design team will have said that it sounds good enough to them.

Not everyone will want to record a non-speaker emulated signal from the DI out and then pass it through software IRs. A lot will like the emulated signal. So the load box/attenuator needs to have the right features to do what you want.

Personally I’d get a Captor X and use its IRs and record direct from that.

[hotlegs]

Well, I know both Tone King attenuators, the 100 Watt version (this has a selectable DI and line output. The DI output is frequency compensated for direct recording, switchable axis between cone or edge.

This from the manual:

Line Out
The Ironman II's Line-Out jack provides a line-level signal that can be used to drive another amplifier, mixing board, computer sound input, or any other line level input. This is useful if the Line-Out is being used to drive another guitar amplifier, where you need to reduce the level to avoid overdriving the guitar amplifier. The line-out signal is generated from the amplifier input, and does not change as you vary the attenuation knob. The line-out signal will be present even when the attenuator is bypassed. The line-out signal is a non speaker simulated output.

DI Output
In this new design Iron Man II design we included a cab-simulated (OP amp driven) balanced XLR output XLR output. Comparing this analog circuit to some of the most intricate computer-based IRs, we achieved a great sounding output you can send to front of house or use in the studio. The XLR output includes a ground-lift, level, and center/edge of speaker cone simulation switches.

The Tone King mini 30 Watt has only a line out, not marked in the manual as frequency compensated.

Line out: Recording / DI out, impedance 10 k, level -10 dbu

The sound of the mini sounds not frequency compensated for direct recording (I know, how these palmer, redbox etc., all these passive compensated DI boxes sound. Like you said, these are build by resistors and capacitors.

Best how you can describe the line out of the TK mini is, it sounds wit a blanked over the speaker. Anyway, I don't have a problem with the unit, I take it for level reduction and not for recording (Fender Tweed Deluxe) and this sounds very good - better than the captor x with his two choices of attenuation. For a well build loadbox (silent recording) I prefer suhr reactive load or fractal audio x-load. These are reactive loadboxes simulating the behavior of real loudspeakers and they have very clean DI outputs for feeding IR via DAW or feeding another poweramp.

I'm only answering to the first post:

Hi everyone,

Bought a Tone King Iron Man 2 mini. The attenuation is really fantastic! But not sure about the line out. Sounds dull to me. Anyone has the same experience?

and I have the same experience.

Michael

[Guitarking]

Would the Two Notes Cap 8 ohm have a clean line out? As I already have the Iron Man 2 mini, all I need is a good load box with a clean di and the Cap 8 ohm is pretty affordable.
Again the attenuation of the Iron Man 2 mini is very good.

[hotlegs]

Don't know about the quality of the Two Notes. Fractal Audio X-Load is working perfect, they have a sale for 299.- dollar.