Mesa Customer Support....MKIV content.

Mesa still has some of the best service on the planet.

Just got my 92 MKIV A from Mike Bendinelli after cap job, all new tubes, and other service.

No way I could do everything on the invoice in 3.25hrs.

01/05/22 Mike Bendinelli: A shorted .1/400 v cap at the bass for ch 3 caused the static and crackle and jumping plate voltages at V1. Also dirty pots and pulls, and when input cable is unplugged the short contact was not closing well. Fixed and cleaned the jack. Cleaned all the pots, pulls, pre tube sockets, jacks etc. The switchable loop jack was also intermittent. Rebuilt the output Lvl pot. Replaced all the electrolytic caps in the amp, all were original. Upgraded the .1/400 caps at V5 to .1/600 volt. Rev plate resistor was far off spec, replaced. Added grid isolation resistors at the class A/B tubes. Soldered all the “crimped” LDR extender leads on stacked LDRs. Cleaned a couple sliders and relubed as needed. Rev well with bench tank and w/ bench FTSW all is good. Install new set of tubes, burn in and playtest.
Labor 3.25 hrs.

I did recapping of my other MKIV myself. It turned out fine but took me a lot longer.

It sounds marvelous and phantom quiet!



They really did a great job of separating the tubes in their own packaging, and molded foam packing of the chassis (sent the chassis only without tubes). I watched the UPS Driver claw it out of the truck and drop it 4 feet in the truck. I don't want to think how much worse it was handled on the way.

Mine needs to go in one of these days.

stephen sawall said:

Mine needs to go in one of these days.

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I highly recommend you send it in soon. And if you're comfortable doing so, pull all the tubes and send in just the chassis. Get all new tubes. It's not as expensive as you think. Package it yourself and don't let the clowns at the UPS/FedX branded stores do it (especially FedX).

The Godfather of Mesa Mark Repair Mike Bendinelli is due to retire soon. How soon, I don't know.

There are none better in my very humble opinion. My MKIV-A still has his initials on the chassis when it was made "MB/92".

When I sent mine in, I politely asked them besides the re-cap job, to go over it slowly and carefully. I told them to spare no expense making it "right".

It was $675. I personally consider it a bargain based on what the market is for used MKIV's of any iteration at the moment.

I'm still marvelling how damned good mine sounds to me!

No scratchy pots, switches, jacks. No volume blooming.

I may have to cancel my MKV 90W order I've been waiting on since 9/2021........we'll see.

I have all new tubes in it now. But the amp is 31 years old. I am the original owner from the first run. My Tremoverb and Heartbreaker need to go in too.

stephen sawall said:

I have all new tubes in it now. But the amp is 31 years old. I am the original owner from the first run. My Tremoverb and Heartbreaker need to go in too.

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You have some great old amps there.

I was reluctant to send mine in at first. I usually do all my own work being an Electrical Engineer and ham radio operator most of my adult life (I'm 63). In fact my first of 2 MKIV's, I did the cap job myself. I did fine with that one, but I took my time with it and didn't enjoy it because there is such little space to work in. Most all the components were packed so tightly. It is so easy to damage things if you're not careful.

Looking at some of Mesa's new amps, (like the JP2C) holy hell! They are packed so tightly (components on the PCB's that is) there is no way I'd ever attempt much with that one! Forget it!

Of course someone like the Master Mike Bendinelli probably does this type work on these amps almost every working day. He's going to be so much better at it, and faster. Obviously he is just that. To me personally, it is money well spent. I'm certain there are many other competent techs, but I don't care to take the time to vet them.

Sorry for the long rambling, but I'm just so impressed with Mike and Mesa service as a whole. It has truly re-awakened my appreciation of these fabulous Mesa amps.

Put my newly serviced MKIV thru about 5hrs of serious thrashing at volume. All channels, all modes.

It prefomed flawlessly and sounded better than I can ever remember.

I've got several other amps (Wizards, Matchless, Friedman, Soldano SLO). But right now my Mesas are back in rotation. These Mesas are truly every bit as good (but different of course). I had been overlooking just how good the Mesas are.