Notice: Use of undefined constant ENVIRONMENT - assumed 'ENVIRONMENT' in /homepages/13/d196653653/htdocs/webseiten/hughes-and-kettner/blog/bloghuke/wp-content/themes/hk-blog/library/functions.php on line 112
Extra Small

Guitar amp sag and the unique Black Spirit 200 power amp Sagging control explained


Most of the classic guitar tones from days of yore revolve around a massive tube amp being pushed to within an inch of its life. Indeed, back in the day, cranking your amp to 11 was often the only way of getting the best sounds out of your – almost literally – sagging amp. These days, though, it’s a different story, with master volume-equipped amps offering preamp gain instead of power amp sag, and now with Black Spirit 200, there’s a game-changing new sag machine in town! And best of all, it won’t make you go deaf either…

Every time I come back from a run in the woods, I feel happy – delightfully drained, sweaty yet satisfied, bushed but blissful, pooped yet pleased, out of gas but on cloud nine.

I could go on, but you catch my drift.

If you enjoy the occasional jog around the neighborhood or backlot pickup game, you may have pondered that weird contradiction of exhaustion paired with elation.

What is it about pushing hard at the limits that brings out the best in us?

Maybe it’s those endorphins and endocannabinoids give us that natural high.

Or maybe it’s something else, something like Voltaire was saying when he muttered those Zen-like words: “The best is the enemy of the good”.

The magic of cranking your amp

Whatever it is, the magic that happens at the borderline of the doable is part of the human experience.

When we start feeling good about being out on the lunatic fringe, it’s all down to biology.

When something similar happens in a tube-fired guitar amp, it’s down to physics.

And the first law of guitar amp thermodynamics is that you have to push an amp hard to get smokin’ sounds.

At least that’s the way it was when bell-bottom trousers flapping in front of speaker stacks was the only way the rock gods rolled.

Our good friend Axel Ritt - guitarist in power metal legends Grave Digger, and long-time H&K TriAmp player - certainly knows how to rock out the way they used to! Although to be fair, Axel's DeeFlexx system also helps him, his band mates and crowds retain some of their hearing after shows... Click the pic to watch our rig rundown with Axel, by the way!

Our good friend Axel Ritt – guitarist in power metal legends Grave Digger, and long-time H&K TriAmp player – certainly knows how to rock out the way they used to! Although to be fair, Axel’s DeeFlexx system also helps him, his band mates and crowds retain some of their hearing after shows… Click the pic to watch our rig rundown with Axel, by the way!

Everything louder than everyone else

Back when rock guitar playing was a visceral experience and VOLUME in big, bold capital letters was de rigueur, the unofficial guide to great tone only had two rules:

  1. Crank the volume to 10 (or 11 for the Nigel Tufnels of the world) and it will get loud.
  2. Crank the volume to 10 and your tone will get good.

That kind of volume may have sent small animals scurrying for cover and the neighbors in search of shotguns, but it also made the amp more touch-sensitive, responsive, smoother, and somehow more musical.

It was as if the angel of amplification had descended from tone heaven to breathe life into an inanimate object.

Suddenly, the amp was animate and eager to assist your efforts to emote like Nicolas Cage hogging the scene in some B-movie.

What is power amp sagging?

This sagging effect is down to inefficient tube rectifiers.

They just can’t keep up with the constant demand for full-on power.

The output voltage drops – that’s the infamous sag that yields such lovely tube compression.

As the rectifier recovers and the voltage climbs back up, you get that bloom that players go on and on about.

Oh, sweet tubes, we do love cranking you!

Oh, sweet tubes, we do love cranking you!

There’s that sports analogy again – push as hard as you can and good things will happen.

When the amp is balancing on the tipping point to meltdown and the power output is at the pain threshold of normal human beings, that’s when sound feels like something physical flying off your fingertips.

At the risk of piling on the cheese, that’s sort of what the whole rock ‘n’ roll idea is all about – living on the edge!

And by the way, we previously wrote in more detail on this topic right here.

Pushing your amp to the limit

How ironic, then, that all this sound and fury is the ultimate expression of puniness rather than power.

It’s actually down to a struggling component’s inability to keep up with the unrelenting demand for power.

This weakness would inform – no, dominate – the signature sounds of iconic 60s, 70s and 80s music styles.

The electric guitar – that phallic emblem of youth and virility – sounded best with a sagging amp. I’ll spare you all the many off-color jokes that come to mind here.

Leo Moracchioli from Frog Leap Studios getting into full sagging mode with TriAmp Mark 3! Watch the video we did with Leo where we talk about TriAmp, tones and much more by clicking this picture.

Leo Moracchioli from Frog Leap Studios getting into full sagging mode with TriAmp Mark 3! Watch the video we did with Leo where we talk about TriAmp, tones and much more by clicking this picture.

Preamp gain versus power amp sag

Back in the day, most recording studios relegated amps, or at least the speakers, to isolated soundproofed rooms, so obscene levels of volume were not a problem for the folks behind the glass.

But when the master volume knob arrived on amps, it served up all the distortion anyone could wish for – at room volume.

The downside is that all this grit comes from the preamp.

This low-power stage serves up oodles of gain without a struggle, so there’s no sagging to be had at the front end.

This marked the birth of that sterile 80s high-gain sound.

On the upside, playing the electric guitar was now much easier on the ears and internal organs as the volume levels dropped.

On the downside, those goosebumps moments when one was one with a sagging amp were history.

I mean, just look at how excited this lot were to be able to actually crank and experience the full wrath of a vintage Plexi for once:


Sagging comes from amps, not FX pedals

This effect is not easily copied, for it is far more than just an amalgam of compression, distortion, EQ and dynamic modulation unique to each player/amp combination.

Perhaps this is why most attempts to mimic the response of a sagging amp in floor pedals have fallen short of the mark – at least that’s been my experience.

Some of you will disagree, pointing to this or that cherished pedal.

And more power to you, but in defense of my opinion, I give you this: if we look at sagging as a separable effect, we have to consider where it belongs in the signal chain.

It’s pretty much the last thing the signal sees before it hits the loudspeaker, so that’s where the effect needs to go – in and not in front of the amp.

Now for the final ironic twist in this piece: Hughes & Kettner has come up with a way to build sagging into the award-winning Black Spirit 200… the irony being that this is most definitely NOT a tube amp.

The Spirit Tone Generator is responsible for all those goosebumps-inducing tones in Black Spirit 200...

The Spirit Tone Generator is responsible for all those goosebumps-inducing tones in Black Spirit 200…

Get your sag on with Black Spirit 200

If the interweb had a Speaker’s Corner, I’d take the stand and loudly proclaim that its sagging is indistinguishable from that of a true tube amp – that’s how well this amp nails the effect.

It gives you eight different levels to choose from, so you can dial in just the right amount of sag for each sound, be it clean or high gain.

It’s like the ultimate spice – nearly everything sounds sweeter with a dash of sag.

You can nail that Hendrix thing with a sound that occupies the middle ground between fat clean and crispy crunch:


You can dial in the sag of a stack on the verge of meltdown.

Or you can put some muscle into your squeaky-clean Tele-driven country twang:


The unique combination of its Sagging feature and Spirit Tone Generator (read more about that genius invention here!) lends Black Spirit 200 true tube flavor.

Lots of tube amps offer authentic tube sound, but how many are as versatile as this?

How many can deliver all that cool tone at any volume level?

And how many let you store those sounds in combination with eight different cabinet types, as you can with the revolutionary Red Box AE+ DI output?

I wonder what Jimi would have had to say about the Black Spirit 200. Perhaps: “Are you experienced”?


First published: April 26 2019. Most recent update: April 26 2019.

And if you liked this post, try these too:

Leave a comment

Neal Dolan on October 25, 2019 Reply


Can you turn on and off the booster of the black spirit on the H&K foot pedal in a live setting ?

    Hughes & Kettner Hughes & Kettner on October 25, 2019 Reply

    Hi Neal,

    Sure you can! You can either use the amp/pedal in Stompbox Mode, where there’s a dedicated Boost On/Off switch, or you can do it using Preset Mode. For that, simply take the preset you want to add Boost to, and then duplicate it with the Boost on in another slot (say 1A and 1B). Then you’re left with two identical preset sounds, just one of them has the Boost on, and you switch between the two that way 🙂 Easy!

    Hope that helps,

    Team H&K

Ken Ogawa on July 30, 2019 Reply

Dear Sirs,

I am one of Japanese guys who loves rock and fusion music.
I have been enjoying playing the electric guitar for more than 30 years.
I bought your “Black Spirit 200” two days ago from IKEBE GAKKI(=one of Japanese famous musical instruments shop).

I am almost satisfied by its specifications, but I have a few qiestions.
If you answered my questions, it would be appreciate for me.

Question #1
My Black Spirit 200 is connected to TubeMeister 112 Cabinet now.
I connected some audio player to “AUX IN” of back panel by cable to sound the backing track to play the guitar with it.
However I could not hear any sound from TubeMeister 112.
I could hear the backing track and my guitar sound just only from the headphone through the phones/line jack.
Is this normal situation? When I use “AUX IN”, I can not hear the sound from TubeMeister 112 Cabinet?

Question #2
I really expected the operation of Black Spirit 200 from my iPad by using blue tooth, however I can not do that now.
How can I get the application software for it? or it is still not available?

I am so sorry for my poor English! I do hope your understanding.
Thank you very much for your cooperations in advance. 🙂

Ken (from Japan)

    Hughes & Kettner Hughes & Kettner on July 31, 2019 Reply

    Hi Ken, thanks for writing us, and congratulations on your new Black Spirit 200! We hope it brings you many years of musical inspiration and great tones 🙂

    Now, about those two questions. When you are connected to the Aux In, the amp sends a stereo signal to the headphones out, and a mono signal to the cab. But you will need to set the amp to Fullrange Mode (not Cabinet Mode) on the back panel, to hear any sound through the cab! So try this, and you should be OK. And using the headphone out you can send the signal to your home hi-fi system, or even a passive (i.e. non-powered) monitor speaker.

    Secondly, the App is still available in Beta format (we are still waiting for the certification from Apple for the public version). But we are sharing the Beta link with everyone until then, as the Beta App is identical to the finished version. You can get access to it here (you will need to download the Testflight App to get to it, but all the instructions are here):

    Again, try that and let us know if it works!

    Good luck 🙂

    Team H&K in Germany

Mario Barroga on July 20, 2019 Reply

When will the soft cover for the BS 200 be available?

    Hughes & Kettner Hughes & Kettner on July 23, 2019 Reply

    Hi Mario, it’s out now, and you can order it from any H&K dealer 🙂

Paul roberts on July 2, 2019 Reply

Even got the t shirt I have 3 h&k switchblade and now black spirt 200 head tm212 cab. Love them all. Marshall WHO!
But the FSM432 would be the ultimate if it had a tuner built in
It would be the must have footswitch would love a tour of the factory as an English man brexit who. Thank you for producing great products. O and make a water proof cover for the cab

    Hughes & Kettner Hughes & Kettner on July 18, 2019 Reply

    Thanks for all the kind words and the feedback Paul! We’ve passed it on to our R&D guys 🙂

    That’s quite an H&K family you’ve got there, and if you’re ever in the St. Wendel, Germany region let us know! We’ll show you around for sure!

    Team H&K

Seni on May 28, 2019 Reply

Hi, still waiting for the Black Spirit Android or PC app. The Presets are not really usable without it. Would not have bought the amp if I knew there is no app coming. Regards. SH.

    Hughes & Kettner Hughes & Kettner on June 3, 2019 Reply

    Hi SH, the beta PC App is here:

    Apologies for the delay on the Android version, but it’s also in the final testing stages, and should be released by our R&D guys soon! We’re sorry you guys are all having to wait, but we want the app to be perfect when it does come out, and hopefully it’ll be worth the wait when you get it 🙂

    All the best,

    Team H&K in Germany

OC Keith on April 26, 2019 Reply

I have just ordered a Black Spirit after reading this! I have been looking for an amp that I can practice, rehearse and gig with for a couple years now. Couldn’t quite get on with the GrandMeister for some reason, but I can’t resist the Spirit! Great blog guys! This really helped me make my decision 🙂

OC Keith

    Hughes & Kettner Hughes & Kettner on April 26, 2019 Reply

    Wow, happy to be of service Keith! We’re pretty sure with Black Spirit 200 you’ve reached the end of your search for an amp that can do all those things 😉 Enjoy your new amp, and we wish you many years of great tones and musical inspiration with it.

    Rock on,

    Team H&K in Germany