How to get more low end/thickness out of grandmeister?

No matter how much I roll back the mids/treble, I just can not get a good low end out of the amp. It all sounds thin and kind of harsh. I'm running through a Marshall 1960A 4x12 cabinet. I want a THICK WARM tone.

It's especially pronounced when I run a fuzz pedal. God does fuzz sound awful through this amp. When I run through my Big Muff opamp the thin/harshness is unbearable. Really considering taking this amp back.

This one is almost as old as I am Discotoads.  We have been trying to do just what you say since I joined in about 2015.  One of my own major criticisms of my GM36 is that it has a bass control which seems to do nothing.  There are suggestions as to a few areas which you can explore to help improve the problem but no final solution yet.  I'm personally looking for a range of tones which is based around a 1960s/70s classic rock sound.  Think Cream/Rolling Stones/Free/Bad Company/and - the forgotten best rock band ever - Humble Pie.  My own amp is a GM36 while your GM40D should be a little better in that respect but it still isn't perfect for me.  We should remember that every amp is made to fit into a slot in the market.  H&K are Germans, ya?  They are a nation whose national identity is based on metal of the heaviest chuggy chug chug chugga chug kind!!!     There is no getting away from it, their amps reflect that in their voicing.  At the end of the day you have to consider, maybe the GM40D is not the amp for your own genre of music?  I still haven't cracked this one and managed to get my GM36 to sound right, or get the courage to get rid of it as I love what else it does so much.  So, on to some ideas to play with.

Speakers are the starting point and in my estimation the most important one by a mile.  The GM series is very very sensitive to your choice.  What I say from here on about speakers is only my own experiences, there will be others who absolutely love the things I hate and vice versa.  On the other hand there are a lot of people who agree with these ideas.  You can only try what you can.

I have tried running my own amp through a number of speaker types.  I started with Celestion V30s in very basic 1x12" Harley Benton cabinets.  They are, for me, a disaster.  The GM36 sounds strident and rough in the top end and lacking at the bottom and no amount of dialling back on Gain or extreme tone control settings remove that.  This is odd because the H&K TM212 cabinets actually use V30s, although they are specially voiced for H&K by Celestion which can make a big difference.  The fact that they are "vented", (don't confuse that with "ported", they are not fully reflex loaded, it is just a couple of small round holes in the front panel), is most likely neither here nor there.  People do report that they are a good match for the H&K amps, just as you would expect.  I have an original mid-1960s Marshall 4x12" top cab with G12Hs in it!  Yes, the much sought after Hendrix versions, all original.  I've had it since about 1970 and it has moved around with me ever since.  They are definitely more mellow than the V30.  Even they still aren't what I really want to hear.  When I was gigging the GM36 I wouldn't take them out to play live.  I used either 2 or 4 modern Celestion G12M Greenbacks which did smooth the sound out a bit but not enough to become the solution.

You would definitely need to actually try out, that is actually audition, your GM40D with different speaker cabinets live to get any meaningful idea of how good they will sound.  Buying based on taking advice from others online will be 99% certain to produce expensive disappointment.  The terms I would use to describe a sound to you are not the same terms you would use to tell me what you are hearing.  My terribly bass light may be your exquisite punchy crisp.  So look on the forum for speaker queries and answers and keep in mind they are pointing you only to areas to explore yourself, not to buying solutions..

Next, consider your pickups in respect of their loading.  Look at this forgotten or misunderstood or just plain ignored issue which I have found is very useful to understand and which can definitely make useful differences.  It's based on the engineering concept, (a very real one), of trimming your input load conditions to match the guitar output a little better so as to shift and tame the high end resonance which all pickups have.  It can be trimmed to one which may suit your needs better.  Have a look here:  Forum thread on pickups and loading, and here is an independent site which explains the same more fully:  Secrets of Guitar Pickups.  Skip down that external page until you see the diagrams about the resonance peak.  It may be engineering and involve mathematics but is isn't rocket science if you put your mind to understanding it.  An ounce of solid engineering fact is far better than a ton of internet "common knowledge".

Controversially, as I'm sure you can guess I will recommend if you have read my posts, I would steer clear of spending time and money chasing magical valve changes.  I have always preached that there is absolutely no engineering evidence that valve makes sound consistently different despite the millions of pages of guitarists discussing ad nauseam how many 12AX7s can dance on the head of a pin!  The factual evidence clearly shows that any real differences are at best subtle and are about the individual valve, (production spread), and not from any manufacturer.  The idea that a Sovtek valve will make your amp sound significantly different to a JJ flies in the face of everything electronics design and component manufacture is about.  Circuits are actually designed so they don't!  However, I speak only as a very experienced design engineer so of course my "opinion", (a non-fact based belief as opposed to a factually supported explanation), of this is unsound compared to an internet amp expert who has sold many many valves to the gullible based on his knowledge of how each make of valve sounds different.  Believe it or not as you will, it's your money!

Understanding the gain/distortion structure of the H&K amps and learning how to simplify the way you create your own distortion sound is also very important.  Try reading this if you haven't already found it:  How To Use The Input Buffer.  You will be making the problem worse if you try to use too many sources of distortion.  Simplify your overall use and things smooth out.  I am currently using a Fender HotRod DeVille 4x10" with a Fryette PS-100 and with my new pride and joy, a 1980s Yamaha SG-1000 I picked up in Tokyo recently.  It sounds rough if I hit it hard just as its reputation predicts.  It sounds delightfully rich and creamy when distorted as long as I use the low gain input socket and keep the guitar volume down to about 5.  Too many guitarists believe that "hitting the front end hard" is the starting point to getting a great distortion sound.  Well, it certainly is the way to begin generating a good square wave and that means removing every bit of character in the sound so that the guitar model, the amp and the player contribute nothing in the end!

Lastly, you could even try the Mitchell Doughnut dispersing devices described by Jay Mitchell.  Despite those aforementioned "online gurus" rubbishing them and recommending Beam Blockers which, just from the Physics, can not do anything to block beams, the Mitchells work!  And here is a description of what they are and how to make them:  Jay Mitchell on how to make the Doughnut Beam Disperser.  Jay Mitchell is an audio wizard who makes no money from his idea.  He is so fed up with musicians' refusal to even try to understand the science of what is going on that he now will not talk about them any more.  He now feels, if they want to be mugged then go out and be mugged.  It is based on absolutely solid engineering and Physics fact and I can tell you, they work!  The Beam Blockers sold as a competitor do not and CANNOT work to prevent beaming.  They will make other sound differences which a guitarist may well prefer to the original sound and that is to the good, but they have not stopped beaming.  They are based on incorrect Physics from the start, top end does not in any way come from the centre of the sound column so blocking that path with a reflector does not "bounce the treble outwards and widen the beam".  Their design actually accentuates the effect because beaming is caused by sounds from different locations on the cone interfering with each other and the largest contributors are sounds from opposite edges.  That's in the Physics.  You can't fudge it!  I have a set of these I made properly years ago and they do darken the sound evenly as is predicted, not a huge amount but definitely a drop in the top end and the roughness.  For me this definitely helped with my GM36 issue, just once again not enough to prove to be the final solution.  Here is an Instructable on them too:  How To Make 'Em.

I would suggest doing a bit of reading of the links, then decide on what you are going to try out as potential solutions, then take your time exploring with an open questioning mind what you can.  Don't spend out large amounts of money on "possible solutions", audition things for free first.  And work with that questioning mind while you give things time to digest.  No legitimate advisor will be upset by your questioning what they say.  I personally love it when people ask me how I can justify any claims I make.  No decent shop will refuse you bringing in your GM40D to audition a range of speakers with it.  They shouldn't expect you to make a decision to buy on the day either.  Take your time.  This is a long standing issue and only some find their full solution.

It honestly confuses me when I see comments like this.

All I can think of is that you have a faulty GM40 or it's something to do with the acoustics of the space you're playing in.

The GM40 has plenty of low end, and I usually have the bass + resonance at just over half way.

I've played the GM40 through Marshall, Peavey, Mesa, Orange and H&K cabs. It sounded different in all of these but it never lacked low end except through a Mesa - but I'm sure it was just the room acoustics. I tried it in a similar model Mesa cab in a different room and it sounded fine.

It's good to hear that you have no problem with your own GM Johnny but I can assure you this has been a complaint for all the years I have been on this forum.  I have owned a TM36 and now have a GM36 and, granted this is not a GM40D, they both were and are very bass light to my ears.  These amp designs are all so complex with multiple interacting switched frequency contouring for each or groups of the channels that you can't just increase the values of a handful of coupling capacitors and correct this in any meaningful way.  German musical tastes lean towards high gain metal and their amps were voiced with this in mind.  The H&K amps were at one time definitely lightened up in the bottom end to prevent muddying at higher gain settings, I can point you to areas in the schematics where this has been applied.  The result of this is just what you see here, an amp which many people find has almost no bass at all to speak of and with a Bass control which does next to nothing.

I have tried it with a pair of 1x12" Celestion V12s in a mini stack.  It looked great on stage but, not surprisingly, they were pretty much a disaster with the H&K.  They ripped my ears off and no had bass whatsoever.  I moved on to partnering them with my mid 1960s Marshall 4x12 loaded with "Hendrix" G12Hs.  That was a little better but still very strident and middly and the bass control again did pretty much nothing.  I have a 2x12" I built myself with G12Ms.  It's great with other Marshall and Fender amps but the GM36...  Well, you can guess.  I've tried it with other speaker combinations and none of them completely get over the slightly nasally middle, strident top end and light bottom end.

As you will see from other posts I have made over the years I have explored lots of other ways of taming the top end and fattening the bottom end.  I've definitely learned to improve some of the problems that I perceive, (with the emphasis on "I" as not everyone will see things that way), and some tricks and tips have become clear on the way.  However, though I really love the H&K amp philosophy and the robust engineering, I just can't get these amps to work for what I want.  And there are many many others out there who give up on these amps for the same reasons.  You only have to read some of the existing threads to see that.  (Remember, I have had to read every thread that appears here for a good few years so I do have a fair picture of what people who post here think.)

I'm sure that there are many many more people out there who are perfectly happy than who post here with complaints and negative comments.  I'm one for trying to take into account the "silent majority" in discussions of opinions.  Tonal quality is genuinely an "opinion" whereas correctness of technical matters is not.  Other forums out there seem to think the opposite and that everything is opinion and they are patently wrong in that.  But, in the main, they do not give good sound engineering advice, or at the very least it isn't listened to and is swamped when it is given.  They are mostly "unknowledgeable" guitarists swapping "common knowledge" and internet myths about the way amps work (or don't).  Given my lack of sympathy with unfounded "opinion" where people are not prepared to be questioned and to have to justify their claims with factual proof, this forum will mostly attract those with "bad feelings" or a problem they need advice on and not usually those who love the sound their amp makes and want to swap unfounded "guru talk".  We have to be aware of that.  But the number who come here and comment negatively is not small and they are not people with odd requirements.  You are one of that silent majority and I'm extremely happy for you to be satisfied with your amp.  Don't rule out the many other people who have different criteria they need fulfilled and different experiences when using their gear.  Perhaps your genre, style of play and accompanying kit, or just the fact that your ear is looking at a different benchmark, make your perception of the amp's capabilities a happy and fulfilled one.

"Perception is truth".  How each of us perceives things, correct or not, is very often the absolute truth for each of us.  (Given the ability to back things up with rigorous testing of course.) The wise man is the one who recognises that perception depends upon where you are standing at the time.

Of course it's all subjective. But that's my subjective experience - it has plenty of low end, even when I compare it with my Mesa Rectifier (known as an amp with a very thick sound).

One thing that I do find interesting with the GM40 is that you actually hear more low end as you dial up the gain. I find that this is the opposite of a lot of amps - with the Mesa, for example, there is a point where adding more gain thins the sound out.

I also think the GM40 has a lot more treble/presence on tap than most amps, and that's perhaps why people perceive it as being harsh.

You can dial that out to a degree. But like most amps, the GM40 has its own sound and there's only so much you can change it by fiddling with the EQ. When you're actually playing with a band, the tone settings don't make much difference IMO.

A couple of excellent points in there to my mind Johnny.

"When you're actually playing with a band, the tone settings don't make much difference IMO."  I'm totally with you on that one - in spades, it's crucial!  I think, there is way too much emphasis put on listening in your bedroom to noodling through an amp at very low levels and arguing about how many 12AX7 brands can dance on the head of a pin!     All tone fixated low level playing creates is a player who has lost sight of his playing and is obsessed with his tone junkie "perfect in my head, tone just like my hero..." goal.  The real life test is to get out there with other musicians and see how little difference that infinitely detailed tone makes in a band mix situation - just as you say.  Sorry if it seems patronising but I would describe you as a genuine real live player with that opinion.

"One thing that I do find interesting with the GM40 is that you actually hear more low end as you dial up the gain. I find that this is the opposite of a lot of amps - with the Mesa, for example, there is a point where adding more gain thins the sound out."  Again I would agree with you entirely that this is usually the case in many designs.  I don't have first hand experience of this in the GM40D but my GM36 seems to have that built in.  The thinning out of the sound with increased level seems to be a perceived necessity with most amps nowadays.  People think it is necessary to somehow maintain clarity.  I'm sick of hearing the damned phrase "...cut through the mix...".  It became a standard overused phrase which instantly marked out a guitarist as a "guru" if dropped into his conversation at every other sentence.  I have never had a problem cutting through the mix with any amp I have used.  I have a thing called a Volume control and fiddling with it usually allows me to cut through pretty successfully when I genuinely need to, no matter what my tone settings.  The H&K amps do seem to have a good degree of what you describe built into them, (part of that German Metal pedigree).

For me, the top end of the earlier H&K models, (remember I don't know the GM40D intimately), definitely has a brittle quality.  That is alleviated a lot if you stop following the usual "gain, gain, then more gain, then an extra pedal for luck 'cause I paid a lot for it" philosophy of tone.  I wrote that thread on using the input buffer of the amps to try to get people to learn that "less distortion modes is better".  Learning where distortion is generated in your path and taming it to one source with a touch of assistance from one other can remove much of the roughness in most setups.  I say continuously, I now use a Fender Hot Rod DeVille 410.  It is an amp with a poor reputation for its Drive/MoreDrive channels.  I picked it up so cheaply it couldn't be refused for that reason.  When I first played it I found the reputation to be warranted.  Then I used my head and explored a bit.  Now I play a LP Trad/Yamaha SG1000 into the Low input with the guitar volume set on 5.  The Clean channel Volume is set to about 5 of 12 and the Drive channel Gain to 5 with the Drive channel Master to 6.  It's loud, it's Fender clean, it's creamy Drive and rocking More Drive!  I have the option of using my (cheap) Nux Steel Singer distortion pedal, as recommended by the incredible Paul Stafford Cook, to add a touch of hardness to the input sound, but only a touch!  The amp's harshness has gone and the classic sounds it is capable of creating shine through.  With single coils I would have to adjust upwards but it is still easy to overload to the point of hardness.  That isn't bad design, good sounds can easily be dialled in with a bit of thought, it's just bad usage on the player's part.  My GM36 responds the same with a gentler approach.  But the gurus tell us to "hit the input hard!" for great distortion sounds.  Not in my experience.  If you haven't already read it you could have a look at the "Input Buffer" thread in the GM36 forum.  It applies to the GM40D as well.

For me the speaker contribution is also greatly overlooked.  Dropping your number of speakers when you drop your output level is crucial to maintaining tone.  A guitar speaker driven below its maximum linear excursion will thin out and sound weak.  If 5W is split between a pair or a quad of 12" speakers none of them is driven to that magic point where they light up.  Drop back to a single speaker and you may be getting there.  Speakers add their own unique contribution to smooth distortion which is never considered by guitarists.  I use a Fryette PS-100 Power Station to be able to drop level without losing tone in the amp.  The PS-100 has an extremely good reactive load system which mimics a speaker very accurately for your amp to drive.  The amp can be left driving this hard while the Fryette uses the amp output as its input signal to amplify or to drop its own output level to the speakers.  In order to get the best out of this I have just modded my Hot Rod DeVille 410 to a switched speaker setup where I can select 1, 2, or 4 speakers as the load.  What a difference that makes at lower levels!  The single speaker is allowed to compress as it should and the tone beefs up enormously.  I can really recommend trying that to anyone who has thinning out problems.  It just might be the root of the problem.

Yeah, I'm with you. Learning to use less gain is part of your maturation as a guitarist (and something that's only hit me in recent years!).

I've definitely come across guitarists/guitar rigs that had trouble cutting through the mix.

I have noticed it a lot with Marshall rigs, in particular the JVM amps that were Marshall's 'all-singing, all-dancing' model of recent years.

My band used to play often with some other bands that used them. I'd notice that, no matter how loud the guitar was, you just couldn't hear it properly. Even if it was a 1-guitar band.

Then a guy with one of those amps came and depped with my band for a few shows ( we were a 2-guitar band). As soon as he plugged in it rehearsal, I noticed the same thing. You just couldn't make out his parts once the whole band started playing.

I got him to plug in my £30 parametric EQ pedal that had the right mid frequency dialed in and boom, he was suddenly 'in the mix'.

This was before I had my GM40 and I was using the EQ pedal myself to 'cut through'. I was also using a Marshall cab.

In contrast I think H&Ks 'cut through' amazingly, and that was the main reason I got interested in them. We used to play with a 2-guitar band often, both guitarists had H&Ks, and their guitars were always crystal clear. Maybe that 'harshness' is what you really hear in a band mix.

Oddly I have a JVM205H in fantastic condition.  I picked it very cheaply up not working but I knew it wouldn't take much to massage it back into life.  I was right, all it needed was a reflow of a few pins on the valve sockets and it was good as new.  Playing my old style classic rock it just wasn't what I needed.  If you look at the schematics for them you can see straight away that they are a modern "preamp distortion" based circuit.  The power amp is very tight with high feedback levels and the high gain in the preamps is the source of almost all their tone.  I find they are very much Soso Clean or In Your Face with nothing in between despite all the claims to being highly versatile.  There is more to versatility than giving us a shed load of channels each with just increasing levels of metal.  I really should get rid of it but laziness sets in and it stays under our staircase out of sight.

You mentioned your Eq pedal and I'm with you on that score.  I actually use a Behringer 15 band graphic equalizer in the loop of the Fryette.  You can pick them up really cheaply and as they are stereo units you actually have two to play with.  I don't use it for anything drastic though you can get some nice unusual tones with it, it is just great at balancing out slight response imperfections like you say.  A little adjustment goes a long way.  Joe Bonamassa advised me that was a good thing to do, (in a YouTube vid of course   )

Yeah, EQ pedals are awesome. Especially in band situations. It's annoying that you can spend 1k+ on an amp and still need extra EQ, but that's just how it goes!

Personally I think the recent offerings from Marshall are pretty crap. I have played the DSL and TSL models, which I guess were their big amps before the JVMs, and I thought they were terrible too.

(Although, to be fair, I have heard some guitarists sound great with them)

I also played Marshall's signature Kerry King JCM800 at an event and it was absolute dogshit, really thin sounding amp, which didn't seem to have enough gain despite being a metal amp.

Correct me if I'm wrong but didn't Marshall kinda make a name for itself with the 'classic' amps which didn't have a lot of preamp gain? But I guess now they are doing the same preamp-heavy setup a lot of modern amps have (I dunno, I'm no amp expert). Maybe they're not playing to their strengths these days.

The other thing is that, I think, some of these Marshall amps are really designed to be cranked. Like maybe that Kerry King JCM800 sounds amazing if you turn it up high. But it's just not practical. I genuinely think nobody needs a 100w amp, even big touring metal bands.

I think versatility is overrated really, unless you're playing in cover bands that do a lot of styles. Most amps can only do one sound really well, and the amps that do loads of sounds just seem to have loads of crap sounds.

JohnnyNonsense wrote:Correct me if I'm wrong but didn't Marshall kinda make a name for itself with the 'classic' amps which didn't have a lot of preamp gain?

Yes, their real old original amps were kind of based on the Fender Bassman circuit but they moved on past that to an original Marshall sound. I have a 1960s JMP Super Lead 100 and matching 4x12 slanted cabinet which I have owned since 1969. I will have the amp in my wooden box beside me when I go, can't get the speaker in there, along with the 1965 Gibson SG Standard I bought at the same time! I have to say I don't use any of these for gigging nowadays as they are too valuable and it doesn't matter a bit anyway. My Fender HRDV combo and Yamaha SG1000 are brilliant for live playing. That Marshall amp is awesomely loud, much too powerful on its own for the gigs I play. Since I got the Fryette it has come back into sight again but the Fender does the job much more practically. I also have a JCM800 Split Channel which, again, I think sounds great but it's the same thing and impractical to gig with in UK pubs. Both of these are not what you would call metal amps, that much gain was just not necessary in those heady days of "real rock". Their sound was intended to be much more creamy than nowadays and they deliver that in spades, with the right speakers of course. Power amp distortion is so much smoother than preamp distortion to my ears. A balanced blend of the two is the way the magic happens.

You either love or hate Marshalls, and I personally don't like too many of their modern era designs just like yourself. But they have to keep up with the times for sales purposes and that means harsher tones. I agree with what you say, but if you go back to their pre JCM900 models you couldn't do better. Mind you, I will say that "no one ever walked out on Hendrix at the Isle of Wight because his sound was so crap". And nowadays we know his sound must have been bad because he didn't have oxygen free cables, magic "tone capacitors", a dozen expensive distortion pedals and he didn't even know what make of valves he had in his amps. He must have sounded awful along with Clapton and all the rest!

Being an old crusty myself I love an old proverb, or maybe just a thought which sounds like an old proverb. There is so much truth in them if you think about it. "Too much fuss and not enough play makes Jack a dull guitarist". One of my teachers always quotes (in Japanese) "He who knows it is inferior to he who likes it, and he who likes it is inferior to he who enjoys it". There is a lot of that "knowing it" in the guitar forum I'm afraid. People want to get status by "knowing" all the ins and outs of the latest internet myths that others would recognise and agree with, and they miss the sheer joy of just playing whatever gear you have at the time and not caring about the gear. The last one which really applies here is - - - "Perfect is the enemy of good!"

bordonbert wrote: And nowadays we know his sound must have been bad because he didn't have oxygen free cables, magic "tone capacitors", a dozen expensive distortion pedals and he didn't even know what make of valves he had in his amps.  He must have sounded awful along with Clapton and all the rest!

Don't forget that he didn't have any true bypass pedals! How the hell did the crowd get through it???

You are right anyway. We guitarists get way too bogged down with the tone-chasing most of the time. And in fact, the best players I know seem to be the guys who care the least about gear (even if they do own good stuff).

Tone does make a difference though. Years ago I used to play a rock karaoke thing in Brighton once a month, and because I didn't have a car, I would rock up with my Pod 2.0 and put it straight into the PA.

Eventually one day I got properly mobile and brought an amp to the venue. One of the regular attendees told me that the guitar sounded so much better, he assumed it was a different guitarist until he actually saw me on stage.

(Though perhaps that's just a testament to the difference between amp modelling and real amps. And the Pod was also crap by today's standards!)

Mind you Jonny, the other variable in this topic is the audience. As my fellow guitarist in the band always says about audiences, "what do they know, half are pissed and the other half have no taste anyway. You worry about sounding great and do they even notice?" I don't agree with that way of viewing it - at least entirely, but he does have a point. Just like the Hendrix thing, we assume audiences actually care about the same issues tonewise that we fret over. 99% of them don't. And the other 1% are the fellow musos who will find a way to say you sound crap no matter what. I find the trick is to just play and love it no matter how bad you sound on the night. At least that way you look like you are enjoying your time on stage and that is infectious. I've seen appallingly bad bands rip a room apart just because they had ultimate overwhelming confidence in their superb musicianship and star quality. And there was even Marc Bolan for example...

Absolutely. Great point.

(And in fact, in my last little story, the guy who noticed the difference was also a musician!)