Ground FX Burning Sunn

Let me introduce the Ground FX Burning Sunn.
This pedal was produced about a hundred miles away from my home in the beautiful city of Hamburg.
This is, as the name suggests, some kind of amp in a box version of the Sunn Model T.

I never played a Model T, but I gathered that it has two inputs, normal and bright, and a way to combine both.
The Burning Sunn has two gain knobs, named normal and bright.
It also has a three band EQ.
The topology is a bit of a mystery. I gathered from an introduction in a German magazine that the tubes are emulated using JFETs and that there is some kind of power amp simulation going on as well, but they do not describe how that is achieved.

So let’s get started. One knob is straightforward and holds no surprises at all: Volume.
The two gain knobs however, can kind of twist your mind a bit, at least when you have a passing layman’s education on how signals are passed within amps and pedals. The two gains work independently as one would suspect they do. Turn one all the way down and the other one up, and you get that flavor.
Turn both down and you get nothing (sarcastic comment about stating the obvious).
Turn both up and… they stack. How? I have not figured that out yet.

Let’s not get carried away and finish the description first: Three band EQ. Active (boost/cut), noon is flat.

My ears tell me that the EQ works somewhat unusual. It is post gain, But when you turn up the bass, it feels a bit like some clean signal is blended in, but I don’t think that’s the case.

So how does it sound?
There’s a burning church pictured on the pedal, which is black. The LED is white, and add the metallic silver of the non printed enclosure, the switch and the knobs and you have the full color palette. Black metal.
This could be a clear message. This might not be first choice on a worship pedalboard.
However, the Sunn Model T is heavily used in Doom and Stoner bands, so it might not be that bad?
By that bad I mean black metal bad.

Nonetheless, I started slow. EQ at noon and both gains completely off. No signal passes.
Turning up the gain yielded a terrible noise, and no matter what I did on the bass, nothing changed.
Troubleshoot-mode did not have to be employed for long. I had forgotten to put the cable in the bass and the tip was touching ground.
It was a long day at work.
With the bass plugged in, the noise stopped and I was able to play notes.
Turning up normal gain, I got a decent sound, nothing too harsh or too metal to manage, actually it stays clean until noon. That’s where a pleasant rasp is applied to the natural string sound. Turning up bright gain, I get somewhat the same, but now I get the feeling the normal gain is a bit on the mellow side. Double checking confirmed that. The EQ works, turning up bass gets the floor shaking. Turning up mids makes Lemmy Kilmister smile. Turning up treble ads a nice sparkly feeling to the texture that hits your eardrums. Each of the knobs has quite some range, so don’t overdo it. It feels like the last two increments of the knob travel, there’s a little extra added.
With a single gain turned a good bit past noon, I get a pleasant sounding dirt signal with lots of harmonics, and a certain amount of push back. Playing softly stays clean, plucking harder yields growl, but the notes clear up when they fade. Playing power chords showed a good note separation, each one blooming and driving on its own.
The bright channel has more of the upper harmonics and gives off a … brighter (D’oh!) sounding structure. It reminds me of small metal marbles bouncing on a sheet of metal. A lot of them.
Take the whole range from dirty boost to overdrive, to distortion to fuzz and now cut the distortion out. This pedal does not do your typical high gain distortion sounds. It ventures well into overdrive territory but in this pedal, overdrive shares a border with fuzz, because distortion was not allowed in.
Near the end of the gain knob’s travel, the dirt increases a lot more for the last bit.
When you max out one knob or stack them by turning up the other, you get a bit of spluttery fuzz sprinkled on top. The foundation of your tone is still an angry chainsaw that’s running itself blunt by being driven into the side of a giant cauldron filled with rocks, but the uppermost harmonics are what you get from a muff when you set it to kill.
That’s actually quite nice. You can toy around with the settings of the treble and bright knobs, running bright gain a little higher, but cutting some treble to smooth the harsh top end a little – or you can ride the bright gain a bit lower, compensate with normal gain and then boost the top end a bit. It’s fun to experiment.
The mids give the signal a throaty growl. Imagine a large dog. I mean large. Larger than that. Even larger. Now imagine sneaking into that dog’s home at night. The noise that dog might use to make you aware of it’s presence. The one that weakens your resolve. When you look down you realize you’re standing in a small yellow puddle. That’s what the mids do when you set a growly tone with the gains and then turn the mids knob up.

I settled on both gains around 1 o’clock, the treble set to cut a little and generous helpings from both mids and bass.
Running my P bass into the Burning Sunn into Cali76 / Bassrig Super Vintage, what I got really felt like something I have not encountered before and that is in itself something to be treasured. This pedal tries to rival the feeling and haptic feedback you get with the Fake Plastic Trees. There is an extra nerve wire running from your fingertips to your ears, going direct and omitting the usual path through the brain. You really feel the dirt. You push it and it will both add dirt and push back.
I needed to watch the treble content. Too little and it sounds muffled, but take too much and it sounds too artificial. But there is a path in the center, where it works great. I feel like this could be a great sound to play with a guitar that uses a high gain amp or distortion pedal that compresses a lot. The raw and dynamic signal could really bring some life to a mix. I tried it out playing to a few recordings and it really sat nicely.

Using the Burning Sunn in a live band situation, I tried to match the function to the Origin DCX I usually have in that setting – so I was using it to hit the preamp a little harder and add lots of gain and grit.

What I found was that the DCX does add a fair bit of … I wanna call it “Non-Darkglass-Metallic-Thunder”.
A good amount of presence and a gnarly texture. The Burning Sunn does not get into that range, it stays more mellow and has more of an organic sound in the mix. What I found was that that pedal can really increase the sustain and it’s easy to coax some (wanted) feedback from the amp, even though it sounds quite clean in the mix. It was a lot of fun playing that.

Bonus: This pedal is a great platform to play another drive pedal into.