Sparky Mark

Ah, I see. I was thrown by you referencing a class AB Markbass head alongside the Fender sled when this thread is more about class D comparisons. I willl say that I prefer my lightweight class AB amps to the class D that I've owned (Markbass F500 being one of them). The F1 is indeed class D.

The LMII is also class AB, not class D

Although the LH1000 is a good amp with loads of power, it has a rather limited passive tone stack (that I never liked) and is heavyweight by today's standards. If you can get your sound with the tone stack and the weight isn't a problem then it's a good amp if you really need 1000 watts. Personally, I would go for either of the Bugera Veyron class D heads, one of which is an Ampeg PF800 clone, the other a Genz Benz Streamliner 800 clone. Both have much more EQ flexibility than the Hartke.

I've realised that I don't like the completely black aesthetics of the ABM750 Evo V. It reminds me of the chrome faced RAH600 Evo IV that I owned for a while. It was a fantastic head other than impossible to see the black legends at gigs. The 750 might look better with white slider caps and the black and silver rotary control knobs used on some other Ashdown heads. All black in this instance is far too plain in my opinion. Maybe as they're only built to order you could specify these simple changes?

Other than you asking this same question on FB there's nothing I can see about systemic problems with Markbass power modules? I've read thousands of Markbass related posts both on here and Talkbass and never seen what you remember?

Can you remember what the issue was and/or link to the forum you are referencing please? Thanks

I've never heard of this; are you sure your memory is correct? Markbass changed from class AB to class D power amps sections in 2012 but that was an evolution not because of any known issues.

I usually take two

There's definitely a class AB theme to your amp collection.

At 11kg this is likely to have a class AB power amp.

Post a thread in the stuff wanted forum describing what you want, where you can collect it and your budget.

Do you like the HB 115 cab but just want more volume?

This thread is becoming a text book example of design by committee.

I think sliders are good for saving space on control busy front panels. Otherwise, if you're only looking at three, four or perhaps five EQ knobs on a large (I've never seen a micro 100 watt valve head) front panel traditional pots with knobs are more attractive.

From a separate thread where the OP stated that he bought this amplifier second-hand I get the impression it may be as much as 10 years old. I'm not saying that the previous owner knew of a problem but failure after only two gigs is quite "unlucky". Any Markbass LM sized head (LM2,3, 250, Tube, etc) will slot into this combo. The OP might find a newish second-hand one for less than a repair. I'm also not so sure the authorised repair shop will supply this assembly without performing the repair itself.

Totally agree with the 100 watts is 100 watts, whatever the amplifier type. I've read so many threads about 100 watts V4B initially being enough then not quite cutting it live. There's not a single 100 watt amp that would handle my gigs in a not too loud pop/rock covers band. If the relatively clean settings on a V4B don't work for you I doubt any 100 watt valve head would (not sure how Handbox manage to get more clean headroom?) I have tried the 200 watt AD200B which is probably the minimum I'd be comfortable with. Valve watts tend to sound sweeter at the limit but are still only watts. Over the past few decades 500 and 800 watt bass heads seem to have become the norm and if you really are using all that power on your gigs a 100 watt amp (valve or otherwise) isn't going to be enough IMO.

As a total Markbass fan of the past 15 years my main worry with the brand is product support. Markbass has released many more innovative products during this period than any other marque and my concern is that its authorised repair centers are unable to support many/most of them. My solution was to buy backups cheaply second-hand, but there is a limit to that strategy.

Me too. Here's my 410. No comb filtering issues that I'm aware of and is in two cabs for improved portability.