• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join freeLog in
    Want zero display ads or expanded classifieds tools? Compare plans.

NAD: Mark Bass LM250 - 1st Month Thoughts

This is not a review but my initial thoughts on using it, coming up on the month mark. I come from Ampeg bass, and Marshall JCM800 for guitar, but since I exclusively backup a church choir, clean tones are favored over crunchy tones.

First, I really wanted the ELF as it would be more of a do-all amp for me... pop, rock, etc. However, since it didn't have a separate gain and master volume, the crunchy tones are built in by the designer at certain volume levels. In trying it out, I couldn't quite get the volume I needed at the larger church without getting into the crunch. This was with the 2x8 cab.

Then came Craigslist, and a Hartke HA2500 in absolute mint condition for $100. I didn't know anything about it, and decided to research it, and ask around. Waited too long, was gone by the time I got back to the seller.

Walked into the local GC and wanted to check out the PF350, but they only had a PF800 with a 8x10. Oh Lord, nothing like blowing off the faces of my fellow parishioners in the front pews, not including the choir singers. Scratch that.

The sales dude suggested to try some Mark Bass amps which I noticed had majority of the space in the bass amp section. Never thought Mark Bass would do for me, but I ended up liking the Little Marcus 250. I thought the tone was I was looking for gave the HA2500 a run for the money. I was able to get tones from both that I liked. However, it was nearly $400.

Fast forward a couple of weeks, and Musician's Friend stupid deal of the day was the Little Mark 250 which I did demo at GC as well. So, I drove back to GC and asked if they will price match it. I expected they would not, but the store manager said no problem. Ended up bringing it home for $229 plus tax.

What I like:

1- It gets stupidly loud with a 2x12 8ohm cab. I do have to watch the volume.

2- The VLE, or what's called Old School in the Marcus version. It's a variable low pass filter, and I use to give some thump to my tone.

3- The DI volume. I just set it at 12 o'clock, but somehow I feel empowered if I don't like the sound guy's setting my volume in the mix.

4- It has a dual Speakon connector that accepts a standard 1/4" jack, and it also has a separate 1/4" jack. Since my 2x12 is older, it only has a 1/4" jack input which I've not converted over to Speakon. I'm sure I can call Avatar and buy the plate and jack to do so. I just plug into the 1/4" part of the Speakon on the back of the amp.

What I have not figured out yet:

1- The VPF, or variable pre-shape filter. It's suppose to mid-scoop the tone, but I've not gotten comfortable with it. My thoughts on it's probably due me engaging the VLE, and the treble frequency.

2- The crunchy tones from pushing the gain. So far, it doesn't sound great. Not in the same ballpark as the ELF for my ears. I'm thinking a pedal in the effects loop would be better.

What I don't like:

1- Why is the power button backwards compared to all other amps? Is it an Italian thing? Down is on, and up is off which is backwards to what I'm use to. I keep pushing the top part to turn it on, then have to remember, it's the bottom part.

2- The treble frequency is too high for my taste. It's at 10khz per the manual, and I would prefer it to be more around 4khz, 5khz tops. Other than that I like the EQ frequencies. The high mid is something like 800hz, iirc. So that's quite a jump for a bass amp. I believe the Little Marcus has the treble frequency around 4khz.

3- The VLE tends to cut into the treble EQ and negate it early because it's so high. Another reason why MB should lower it as I suggested above.

4- The black line on the knobs should go up over to the top. It's kinda hard to clearly see when I'm performing. I don't have time to stand there at look, but need to look and adjust quickly.

What I haven't used yet:

1- The tuner out. I have my polytune in line after the G10S wireless and the amp. Don't know if I'll use it because it would not cut signal to the amp input when tuning.

2- The effects loop. I don't use effects much, and if I do, it's usually a compressor and chorus pedal. I should give it a try soon. Some say it's parallel, and it can be converted by an amp tech. Odd, because I would expect a blend knob if it is parallel.


The *** is that thing:

1- There's a black plate to the right of the Speakon connector that's held on by two screws. No obvious function and nothing in the manual about it. Best guess is that Mark Bass uses one sheet metal case for a multiple heads, and it's probably used by another amp head.

Finally, I noticed that Musician's Friend no longer as the Little Mark 250 on their website. Only an open box one. I wonder if the parent company is no longer importing them, or if Mark World is discontinuing it.
 
I am. The VLE cuts treble. It's a low pass filter. It doesn't cut treble clockwise. It cuts it counter clockwise.

I'm thinking mine cuts treble more the more clockwise I turn it. Off is completely counter-clockwise which is about 7 o'clock. That's what I recall off the top of my bald head.

I do use it around 11 o'clock typically. Its the variable pre-shape filter that I still need to pay around with. The version on the Little Marcus seemed quicker for me to get comfortable with.
 
  • Like
Reactions: SJan3 and DirkP
I'm thinking mine cuts treble more the more clockwise I turn it. Off is completely counter-clockwise which is about 7 o'clock. That's what I recall off the top of my bald head.

I do use it around 11 o'clock typically. Its the variable pre-shape filter that I still need to pay around with. The version on the Little Marcus seemed quicker for me to get comfortable with.

You are correct, the more you turn up the VLE knob, the more it rolls off your high end. The VLE and VPF knobs do not play well together. I would suggest turning one down if you want to try the other. The VPF is just a mid-scoop, nothing special. The Markbass cabinets (like your combo) have a pretty strong mid-boost that is hard to compete with. If you ran the head to a different cabinet, you'd probably notice a much bigger effect from the VPF.
 
CMD121P owner.... I ignore the VPF, it's turned off. Scoopy tones are not my thing anymore.
However, the VLE is pretty much always in use with the combo's cab or other tweeter/horn loaded cabs. It tends to get set around 11 o'clock.
The EQ knobs barely get turned much off of noon, so the frequency centers are really not very important, but I can fully understand bringing the treble frequency down an octave or so.
I use a BOSS BB1X for a little grit with one pedalboard, or plug in a Bass Fly Rig into the input or effects return, which also has great grit. Having the VLE set at 11 o'clock really helps the gritty tones sound smoother.
 
I'm thinking mine cuts treble more the more clockwise I turn it. Off is completely counter-clockwise which is about 7 o'clock. That's what I recall off the top of my bald head.

I do use it around 11 o'clock typically. Its the variable pre-shape filter that I still need to pay around with. The version on the Little Marcus seemed quicker for me to get comfortable with.
Whoops! Turns out you're right. Well it has been 10 years since I owned an LMII. But when I used it, I'd keep it somewhere around 9:00 or 10:00. I can't remember exactly, but anything out of that range got too dark or too bright.

Anyway, I hated the VPF. I thought it scooped mids in a bad freq range. I used the hi mid knob for that if I wanted it. Maybe the Marcus fixed that, don't know. I just thought it was absolutely useless on my LMII.
 
Anyway, I hated the VPF. I thought it scooped mids in a bad freq range. I used the hi mid knob for that if I wanted it. Maybe the Marcus fixed that, don't know. I just thought it was absolutely useless on my LMII.

No worries, I get mixed up as well.

I'm still working on figuring out the minutiae of the VPF. It doesn't sound like a straight forward mid-scoop control to me. I'm thinking based upon last night's rehearsal that is starts out as a tame mid-scoop, or like you said not in the expecting frequency range. As I engage it more, it sounds like it's starts to boost low end and cut treble and mid-highs. More like what I consider to be a vintage contour.

Mark World has a youtube channel and it would be nice if they put together a video on the VPF in detail for musicians.

The other aspects of this amp is that it sounded great with the acoustic bass. It did well preserving the warmer, acoustic tone. It also sounded great for acoustic guitars. In this case, an Ovation.

We play through a Bose Panaray system with a sub-woofer for 40hz to about 100hz. All of the acoustic guitars sound horrible going direct to the board and through it. Little to no low-end, or mids for them. Too much treble.

It looks like Bose publishes two frequency response ranges for the Panaray. If it was accounting, one would be the "pro forma' range, and the other would be the GAAP range.
 
  • Like
Reactions: JimmyM
The manual for Markbass says the following:
Vintage Loudspeaker Emulator: max cut range 250Hz-20KHz
Variable Pre-Shape Filter: Center Frequency 380Hz cut

I found this diagram showing what's going on. You are correct, at it's maximum setting, the VPF circuit does boost the lows around 40Hz about 6 dB and the highs around 10KHz about 12dB.
vle-vpf-jpg.578061

mar-ltl-mkiii_3.jpg
 
I use an LMII with a GK NEO 115 cab. When I bought the amp about 6 years ago, I read the following here on Talkbass, which was very helpful. Set up the amp with the filters off and the rest of the tone controls at noon. Get your volume where you want it, EQ using the filters only, and then tweak with the rest of the tone controls.

I usually keep the VLE at about 9 o'clock and the VPF around 10 o'clock. Sometimes I keep both completely off. I'll usually run the bass with the volume and tone rolled off too. Then I'll have some slight adjustments from the tone controls. That all went out the window at my last gig, where I ended up with the filters off and the bass tone knob dimed. But that's also why the method works. You can account for variation in different situations.
 
  • Like
Reactions: SJan3
Internal photo of it. Looks like the Pillsbury doughboy camped out in it for a couple of days.
20191105_091919.jpg

Notice Markbass used the goop to anchor the small circuit board to the case (in the center bottom of the photo). Not sure what to think about that.

Photo of the preamp board. The amount of diodes stand out for me, particularly when I see them in pairs. I think full wave shaping of the audio signal. Interesting. GK does this. Seen this in the Mesa amp as well. Probably most others too.

20191105_092136.jpg


Voltage selection for the SMPS depending upon's one country. Amongst all that goop.

20191105_092302.jpg


What I found interesting is the BJT transistor in what is suppose to be a class D amp. This is a STD03P which I expect in a class A/B amp. I assumed the left one is STD03N (NPN as complementary to the PNP). You can see the top of it peak up through the cables on the left side of the heat sink. I should check it, but perhaps this is a hybrid amp?

20191105_091938_HDR.jpg
 
Last edited: