"0 Watt Power Amp" - Synergy, now Tone King

[jbrrrrr]

I was watching a clip of Tone King's new tube preamp/IR cab simulator box from NAMM 2025, and they're incorporating a "0 watt power amp", which was said to be similar to the tech used in the Synergy Z Wreck model. On the Tone King unit, it has an attenuator control which allows driving the power section harder like an actual full amplifier for different kinds of gain.

This unit has no functional power amp in terms of being able to power speakers directly, so I'm wondering wtf is in this thing - it seems like a cool idea and I'd like to tinker with it, as I'm currently playing with some similar concepts myself for integrating tubes, IRs, and power amp feel into a digital recording "helper" box. From the Synergy page, it sounds like there's a transformer in the Z Wreck unit;

I'm wondering if they're just using a really low wattage tube power section like a 6AK6, and reactive loading it with a small transformer... or if its even simpler than that with less costly components. Anyone got any additional info, insight, guesses, or other topical bullshittery?

New Tone King IR preamp demo video:



Synergy Z-Wreck module description

[jbrrrrr]

For anyone else interested in this: I realized this video actually references 3 12AX7 tubes, so I doubt there's an additional tube for any power amp driver just to dump it into a reactive load.

Also, this Tone King box has an "attenuator" control for both channels, implying that whatever this feature employs, it has two separate drive/saturation channels as well, so any triode involved would have to have two available.

My best guess right now is a low wattage audio transformer like a Hammond 119, driven by a 12AX7 cathode follower or phase inverter stage on each channel. That'd leave 4 triodes to make up the other two channels, + reverb and tremolo maybe being half triode/half MOSFET design. That is the best I can come up with that seems economical enough to fit into a reasonable price point, size, and fit with the 3 12AX7 arrangement.

Kind of an interesting thought to build into a DIY tube preamp box - drive a small transformer with a miniature reactive load simply to garner the upstream impedance effects it would present.

Would love anyone else's two or three cents - I don't think I've heard of something like this being done before.

[Reeltarded]

It is an Impulse Response.

Do you have a way to play IRs?

Here is a Dumble style 102 power section with a Dumblator Stelligan put up for Tonex. I have more than one Tonex with preamps on one and power amps on another. The processor has a 200 sample @48k capacity with 192k (4x oversample) converters. This part cost about $19 and not in bulk.


https://www.tone.net/tonex/tonemodels/66871

And this is the whole amp.

https://www.tone.net/tonex/tonemodels/68071

This is how to use it with one unit. Import the IR wave file as a speaker IR.

lol

[jbrrrrr]

Do you have a way to play IRs?

Here is a Dumble style 102 power section with a Dumblator Stelligan put up for Tonex. I have more than one Tonex with preamps on one and power amps on another. The processor has a 200 sample @48k capacity with 192k (4x oversample) converters. This part cost about $19 and not in bulk.

I have all kinds of fakey-fake versions of power amp captures including Stelligan's that you mention (as well as some for Neural Amp Modeler/NAM - you should check those freebies out too), and they're better than nothing but I'm not opposed to reverse engineering this real-but-fake power amp for the next tier up to the real thing, which ironically wouldn't be any less difficult than getting a 57 and putting it in front of one of my cabs.

The idea of getting that extra fraction of a percent closer to the real deal - especially if it has anything to do with getting that sterile crap plastic feel thing solved with some real components pushing electrons around - is very attractive to me.

From the Synergy page - and that video has some whoever he is claiming that Tone King is using the same thing in the Synergy box:

In collaboration with Mike Zaite the Synergy team resolved this issue by incorporating an actual “0 watt power amp”, phase inverter and small transformer into the module design. This innovative solution resulted in this module authentically capturing the harmonic and dynamic content of the Z WRECK power amp including the “CUT” knob, which is a part of the power amp section.

I'm just gonna try to build this damn thing and figure out what they're doing and whether it's worth it. It can't be that cost prohibitive since they still have to convince people to buy these things, so I'd be shocked if it was more than an extra $60 worth of parts on one of these preamp IR box thingies.

[Reeltarded]

I have not been impressed by Synergy things but I also don't use in-ears. I just watched the video. Umm.. ok, another $1,000 pedal-pedal platform with a guy playing a pedal platform clean sound. It all comes down to cubic inches. I know that these interesting people with interesting ideas haven't broken the laws of physics. I loathe the barrage of Youtube videos convincing me that no, in fact were wrong and nothing ever sounded great, until now. Listen to this hype!

Other than being told, my ears still might not be getting the message.

The graphic from the last time I used an actual TK Imperial melting to record. I Will Go Wrong. Not to be snarky, I just love it because it's funny.

IMG_3082.png

[B Ingram]

I think "0-watt power amp" is just marketing misdirection to explain that while there's a control marked "Attenuation," don't expect this pedal to drive a speaker, or to be an attenuator for one of your other amps.

I was watching a clip of Tone King's new tube preamp/IR cab simulator box from NAMM 2025, and they're incorporating a "0 watt power amp" ... it has an attenuator control which allows driving the power section harder like an actual full amplifier for different kinds of gain.

This unit has no functional power amp in terms of being able to power speakers directly, so I'm wondering wtf is in this thing ...

I'm just gonna try to build this damn thing and figure out what they're doing and whether it's worth it. ...

I think you're over-thinking this a bit, and trusting that there's technical-accuracy in a label or marketing-statement.

It's a tube preamp made to simulate Tone King's Imperial amp, right? You've got the Rhythm Channel with its Treble & Bass controls, the Lead Channel with its Tone and Mid-Bite controls. And you get the Imperial's Trem and Reverb, along with a Dwell control to tune the reverb that the Imperial doesn't normally have.

The actual Imperial amp also features an onboard Iron Man Attenuator, which can be applied to both channels or just the Lead Channel (Page 13 of the Imperial manual). What that does is alter the the volume/dirt balance between the two channels of the Imperial.

So the "0-watt power amp" and the "Attenuation" controls are just the mechanism for simulating that feature of the Imperial: change the relative-loudness of each channel, control the amount of dirt in each channel. You're assuming some analog amp-equivalent underpinning that "Attenuation" control, but it could simply be a pot controlling some part of a digital simulation the way Strymon has various digital pedals with adjustable dirt added to a base effect. Or perhaps it's a not-sexy analog overdrive-pedal circuit. Point is, it only has the name "Attenuation" to mirror a control on the actual amp this is simulating.

[jbrrrrr]

So the "0-watt power amp" and the "Attenuation" controls are just the mechanism for simulating that feature of the Imperial: change the relative-loudness of each channel, control the amount of dirt in each channel. You're assuming some analog amp-equivalent underpinning that "Attenuation" control, but it could simply be a pot controlling some part of a digital simulation the way Strymon has various digital pedals with adjustable dirt added to a base effect. Or perhaps it's a not-sexy analog overdrive-pedal circuit. Point is, it only has the name "Attenuation" to mirror a control on the actual amp this is simulating.

You definitely could be right, and I'm aware of how "technological" this must sound to consumers who have no clue how the sausage is made. If it came from anyone else like Boss or Line 6, I probably wouldn't have thought twice about it. Synergy isn't even really credible enough to me to warrant thinking too much about it. But Tone King has a bit more cachet and I'd be surprised to see them invent a whole "fake" analog circuit section that's really just a post-preamp master volume on each channel, especially since the Synergy version, which they name-checked in the video, uses a transformer in the preamp - so there's at least that going on with this marketingly-named feature.

Ignoring the "attenuation" feature on the Tone King variant, I'm primarily interested in some new way of achieving the post-preamp nonlinearity in a small format, but I'm also aware that between all of the brains on forums like these, something like that probably would have either been thought up already, or deemed functionally insufficient or high effort/low reward. That's kind of what I was hoping to get a sense of - perhaps someone saying something like "oh yeah that tired old fake power amp thing - peavey tried it in 1993 and they just brought it back with a new name".

My personal interest in this is based on the idea that I think a lot of these recording-amplifier-utility things are missing out on how speaker impedance and power tube saturation might have an upstream effect back in the preamp, where these things are actually supposed to be doing the heavy lifting, but can't without having those functional pieces accounted for. I'm a big fan of the convenience of modeling and small format boxes like this, but there's always a "feel" thing that doesn't sit right with me, and I suspect it's something to do with this end of the equation.

At the very least, with preamp tubes running at high voltage, saturating a transformer connected to a reactive load probably does something in the recording output that could be a desirable artifact. That could be all it is, but similar to how some people have figured out ways of faking a phase inverter in single-ended amp designs to fix some of the feel, maybe there's some less-utilized and wasteful way of employing a triode in a preamp pedal format to get another 3-5% more "realism" out of these boxes that would be interesting to at least capture the concept of somewhere and discuss.

Personally, I want to see if taking a small trafo and sticking a phase inverter stage in front of it does anything worth repeating in a box like this - if it helps direct-recorded sounds respond more realistically to an actual amp rig, I wouldn't mind having my own little soak-box thing in front of my audio interface.

[printer2]

No transformer but some say power tube distortion may actually be from the PI. So how do you simulate the power tubes effect on the PI when clipping? Have not tried it, I doodle so many circuits but never get to try most of them.

[B Ingram]

... So how do you simulate the power tubes effect on the PI when clipping? Have not tried it, I doodle so many circuits but never get to try most of them. ...

That does look like it could simulate clamping of the phase inverter's output due to grid-current in the power tubes.

I'm not entirely grasping the changing bias on the '072. Some kind of simulation of sag?

[jbrrrrr]

Some more context that I've unearthed, in case this is making anyone else curious...

From another forum, regarding the Synergy Z-Wreck module which was the first to have this "0 watt power amp" whatever-it-is:

What I find interesting is that this is the first one with a phase inverter in the preamp module in order to simulate aspects of the power amp. Sounds weird to me, but they claim to have incorporated a "zero watt power amp" (including a small transformer) into the module design. Synergy says this idea may find its way into other modules in the future.

It sounds like it might very well be a phase inverter triode, driving a transformer and reactive load.

Maybe the "attentuation" is more like a post-PI MV, just unique to both channels, so you can tailor how each channel incorporates the change in feel from it.

I guess my neophyte question would be whether the interaction with the upstream phase inverter and reactive load would really have a big effect on preamp "feel" - I imagine it would, though I don't really understand how to math that out.

I can see how breaking apart a preamp and a power amp, even into two separate rackmounted units, could miss out on this piece of interactivity - and that'd be a big deal for a Fender-style design like this. In which case, adding one triode and a dinky transformer could potentially bridge that gap usefully in a lot of other use cases as well - even a simple tube preamp/overdrive pedal might benefit from adding this kind of an idea into it.

There's a new Tone King Synergy module made where this tech gets mentioned a bit - sounds pretty great for what is is.

[andp]

Since the "0 Watt Power Amp" topology is also referenced in the Dr. Z Z Wreck Synergy module, I don't believe the attenuation control on the tone king pedal is specific to the 0 watt feature. The attenuation control is just what's on tone king and it's what people expect to see in a tone king imperial control set so I'm pretty sure they just used that word to match the actual amp.

I know the Kingsley uses a 12ax7 in the crucible to simulate the phase inverter which I think is pretty standard. In the tone king pedal there is reverb + trem as well - assuming the reverb is not tube driven, I suppose they could be using just one triode on a 12 ax7 as just a backboard to absorb preamp gain and simulate power amp distortion? Unsure how many stages you need for tube tremolo but there are three tubes in the tone king, 2 of which are certainly dedicated to the preamp.

For what it's worth the Z wreck synergy module (which also has 0 watt power amp) has 2 12ax7s so it may not be a tube driven feature at all!

[Vurguuz]

Over on The Gear Page there is this user @politoleo, who answers questions about the TK Imperial Preamp pedal and the Synergy module. He says he is part of the Synergy DSP team. Here is what he says:

2 preamp tubes and 1 PI tube, power section, attenuation

You and Randal are right! Big part of the tone comes from the poweramp, more so on this model.
That's why there is a actual third tube inside, as phase inverter with the exact same circuit of the amp.
FYI most of the distortion comes from driving it rather than the power tubes, expecially when no feedback is present.
On the amp the attenuator is after the power tubes, on the pedal after the phase inverter.

>> Where does the power amp simulation land in the signal path?

There are 3, phase inverter / attenuation (where most of the tone happens) is a phisical tube before the send.
Then right after the return there is the sag and transformer drive part, it will affect XLR, HP and TO AMP RET
Then last one is right before the IRs and it's the dynamic speaker load one and HF Comp recovery. It will affect XLR and HP.

>> Are the sag and transformer section digital? if so can you make them individually adjustable (as opposed to just on/off) via a FW update? I like transformer saturation but I'm not a big fan of sag. You can REALLY hear the sag when the volume is dimed on the lead channel. It does that amp about to explode thing that alot of people like... but I'd rather be able to crank the gain and keep the low end tight.

Sag and drive are very subtle.
What you are experiencing it's the preamp grid right after the volume overloading because the pot itself act as a grid resistor, when it's full that became almost zero.
Meaning its on the analog part and can't be controlled digitally.
Also Its how the amp is designed (same behavior on the amp itself).
However pushing back the volume slightly will get rid of if without any substantial gain difference.

>> Does anyone know which tube does what on this pedal?

All tubes are shared between channel, V3 is phase inverter and V1 is the first stage for booth channels.

>> I am not a tech but it might be using the 3rd tube as a phase inverter tube and overdriving it and adding to the first stages of gain ...

Yes, Its exactly the actual Imperial amp, but instead of 6V6 tube push pull there is a custom very low power (less than 0.5W) implementation.

>> @politoleo how does the attenuator work on the pedal? Is it more like a master volume or operate more like the actual attenuator on the amp to simulate that?

Yes it's like a master volume, on the real amp that's "high power" but on the pedal is low power since we don't have much more than 0.1W to attenuate.

>> I am not sure what the "0 watt power amp" is. Someone said a phase inverter circuit? So maybe it is a PPIMV?
Yes it's after the phase inverter but different then usual PPIMV, it's actually closer to the "power attenuator" of the amp then a PPIMV, just with different power to attenuate.

>> What is the purpose if the attenuator on the preamp? I assume that's just marketing speak for master volume?
It has the 0W poweramp circuit so it's a post power amp master volume, same as the Attenuator on the amp

Reactive load

>> is the imperial handling IRs differently than the IR-D?

IR are handled the same, but different IR can dramatically change the response.

On top of the different IR (that basically is a 2048 band EQ at its core) there are also a very different Poweramp/speaker interaction sim as it uses different model from IRD and TK.
IRD uses a 412 load with feedback, TK uses 112 combo load and no feedback, just like the real amp.

>> It seems that the TK input/output tops out at about -5db in the DAW, with attenuator and volume knobs both maxed out. Is there something like a brick wall limiter in play or a more nuanced limiter design? I’m curious…

Tube push pull style limiter before IR with TK combo cabinet!/speaker as load sim.

Inputs and outputs

>> @politoleo I wanna make sure I am understanding this correctly. The IR's and power amp sim are only present at the balanced outs and the headphone out? Is this correct?

Depends what you mean by poweramp sim.
If you consider phase inverter ad poweramp thats a full tube beofre the send.
If you consider the static and dynamic response of the cabinet thats only on XLR and headphones.
Transformer and sag sim are also present on "to amp out".

And this has been confirmed by him as the signal flow for the TK Imperial Preamp pedal:

Send
* High voltage all tube preamp and phase inverter from the Imperial amp. 100% analogue and zero latency.

To Amp Return
* Preamp signal converted to digital
* Reverb
* Tremolo
* Transformer and sag simulation

Main Outs and Headphones
* As above plus...
* HF comp
* Lowpass filter
* 20 Hz roll off
* Dynamic IR and cabinet simulation
* Chosen IR file

[Vurguuz]

So going by the above, the transformer response is actually digitally modeled. If I'm reading it right, the reactive load is digital too.

However, building an all analog box with 2 preamp tubes + 1 PI tube and a small reactive load does seem like something worth trying. I have no idea how to couple the PI to a simplified low-power attenuator, e.g. this one, though. What should go between them in lieu of a power section

[jbrrrrr]

However, building an all analog box with 2 preamp tubes + 1 PI tube and a small reactive load does seem like something worth trying. I have no idea how to couple the PI to a simplified low-power attenuator, e.g. this one, though. What should go between them in lieu of a power section

My thought is that setting up maybe one "preamp" stage - really just more of a buffer than anything else, maybe something like a 12AU7 cathode follower two triode thing, into a 12AX7 cathodyne PI with that last triode as a freebie for some extra gain up front if you want it - that should take care of the front end of things sufficiently and justify having tubes and HT in this box. I could see that contributing a fair amount of "amp-ness" to things, and then like you/they said, the rest of it is just dumping the signal in a way that responds similar to the actual amplifier via reactive load. That's where I'd start, anyway.

As far as a trafo, I'd consider just sticking a line transformer in there for a balanced output and seeing if that adds anything "missing" - that would be pretty inexpensive to try.