Used Mark III -- Need Advice

RichW · Jul 2, 2006

Hello everyone, first post of mine here on the Boogie boards. I've been playing guitar for about 10 months and recently bought an EBMM Petrucci signature guitar as an upgrade from a Fender Strat (and loving the guitar!). Unfortunately, I'm still stuck with my beginners/practice amp, a Vox AD30VT--which is excellent for its price range, but I want more.

Now, I've not much personal experience when it comes to tube amps, but I have been reading a lot lately and my knowledge about them is gradually increasing. I have not tried out a lot of amps either, but I already quite know what I'm looking for; the smoothness of a Mark series amp. And whaddayaknow; I spotted a used Mark III amp in a local guitar store. Unfortunately, at the time I was in a hurry so I couldn't check it out properly but I plan on returning there and trying it out.

My question to you folks: what are things to be on the lookout for (seeing as it's a used amp)? Do you have any useful advice to offer when it comes to buying a used tube amp like this Mark III?

Cheers.

lydisk · Jul 2, 2006

ask questions like:

when were the tubes last changed?
all original parts?
year of production? (very important for markIII series as the qualities of the amp vary quite a bit)

check the amp for damages and stuff aswell
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Paul Secondino · Jul 2, 2006

Always check these basic things when trying out any tube amp new or used.

1. Look for obvious physical damage and check all controls for bent knobs, cracks and such

2. Power it up and listen for any unusual sounds like crackling, tubes making ticking sounds, or the worst "burning smells" Do this in stand by mode

3. Take the amp off of stand by ( Set Master Volume to 2) and play it in the clean channel. Listen for any ground loops ( make sure it is plugged into a grounded outlet) Then while on clean channel, turn all the pots and see if any are dirty (crackling noise) or work/don't work. The Mesa Mark 3 has a few push/pull controls so make sure all do something when pushed or pulled.

4. Now it's time to play the amp. Volume (left most control) controls input gain for all 3 channels. So try turning that up to 6.This should make the clean channel sound clean and give enough gain to the lead channel

5. Next pull the control that says "middle" This engages the rhythm 2 channel.

6.Next pull the "lead drive" control to engage the lead channel. Try setting the lead drive at 6 and the lead master at maybe 4 to start. Don't forget to try the graphic Eq and make sure all the sliders work

7. This is jsut to check he options of the amp. Check the back of the amp where the power cord attaches and look for a colored stripe (blue,green,red,purple) Also look for a simulclass switch on the back.And check for graphic EQ of course

IF you already know all hte available options on the mark 3, then disregard #7

welshboogie · Jul 3, 2006

To add to the above, just remember that one of the pull functions will only work on the lead channel - the treble pull shift - it adds midrange to the lead channel.

The pull brights on the volumes are very subtle - except at low volumes.

The store may not like it but ask to crank it a bit 3+ should be plenty to show any transformer/power tube problems, high squealing at volume could be a dodgy preamp tube or excess settings of presence/vol 1.

Good Luck