Accidentally ran my MarkBass head at 2 ohms

[BassFrends]

Had a club gig last night. I used the clubs cabinets with my MarkBass Little Mark 800. Didn't realize til the third set that each cabinet was rated at 4 ohms.... and that I was running my "Little Mark 800" at 2 ohms

I ended up just going direct for the rest of the last set. I got up this morning and plugged it in and everything seems fine. Still kinda worried that I may have messed up my amp though

Any amp experts around? Opinions?

This is my first post on talkbass!!! I've lurked for too long

[BurningSkies]

I'm going to hazard to say your amp is fine. If the amp didn't shut itself down into protection mode and you're not having any problems post-show, I don't think you have any worries.

[3506string]

I wouldn't be too worried. As long as it's still powering on and playing there shouldn't be a problem.

Though I would never recommend running a amp lower than it's min impedance specs you would be surprised at the amount of people who have no idea what an ohm is. I have personally seen people running amps FAR below their min impedance rating and have been doing so far a long time. I just replaced/rewired a power amp at a church that was running 2-4ohm peavey dual 15's, 2-8ohm Fender PA speakers, 2-8ohm Peavey floor monitors, and a 32 ohm stereo speaker all wired up with a mix of instrument and speaker cable off of a single amplifier. The pastor told me they had been running that system for years before the amp blew.

[BassFrends]

Originally Posted by BurningSkies

I'm going to hazard to say your amp is fine. If the amp didn't shut itself down into protection mode and you're not having any problems post-show, I don't think you have any worries.

It did go into protection mode and shut off the speaker. But the direct signal from the head's DI to the house was never interrupted. I turned the amp off and plugged into one of the club's DIs after we finished the tune.

But it does still seem to be functioning normally now.... I don't know what kind of havoc 2 ohms can wreak internally to an amp like that, or what the long term effects could be. I'm hoping it doesn't "seem fine" now and then just die on a gig in a couple of weeks lol.

[iiipopes]

That's the purpose of the protection mode. It did its job. Your amp is fine.

[RickenBoogie]

The issue with running a solid state head below the minimum load is heat. If it were to be over heated for a long period of time, or continually, it would be a real problem, but a one timer, or infrequently anyway, is not so bad.

[BassFrends]

Originally Posted by 3506string

I wouldn't be too worried. As long as it's still powering on and playing there shouldn't be a problem.

Though I would never recommend running a amp lower than it's min impedance specs you would be surprised at the amount of people who have no idea what an ohm is. I have personally seen people running amps FAR below their min impedance rating and have been doing so far a long time. I just replaced/rewired a power amp at a church that was running 2-4ohm peavey dual 15's, 2-8ohm Fender PA speakers, 2-8ohm Peavey floor monitors, and a 32 ohm stereo speaker all wired up with a mix of instrument and speaker cable off of a single amplifier. The pastor told me they had been running that system for years before the amp blew.

LMAO! Gotta love Peavey!

After seeing the rating on those cabs last night, I was thinking the same thing... "whoever put these cabs together had no idea what an ohm is". Not that I'm some expert on things electric, but I do know that two 4 ohm cabs is 2 ohms, and most amps can't handle 2 ohms (makes me want that Carvin B2000 even more).

[BassFrends]

Thanks for the replies. Seems like she'll be fine!

Lesson learned: Always check impedance when borrowing speaker cabs.

[washburn_it]

I have a Parsek BS-4000 that you can consider as the grand-father of your Little Mark 800 (Parsek was the "first" name of the actual Mark Bass) and it has an overload protection.
If also your Little Mark has that protection and it never activated then you never got over the max output current even if you exceeded the minimum load.
You must pay attention to the volume level of course.

Regards,

Roberto

[seamonkey]

Originally Posted by BassFrends

Thanks for the replies. Seems like she'll be fine!

Lesson learned: Always check impedance when borrowing speaker cabs.

There's hardly a chance that anything would blow on the amp. Short circuit protection, over current protection, head protection, ... they would in any case fix it on warranty.

Forget the old wives tales of SS amps. Markbass and all these new modern amp makers really do make the amps idiot proof.

That is until a better idiot comes along.

[JimmyM]

Originally Posted by seamonkey

There's hardly a chance that anything would blow on the amp. Short circuit protection, over current protection, head protection, ... they would in any case fix it on warranty.

you can sneak some stuff by on manufacturers under warranty, but i would think this wouldn't be one of them. however, you could argue that if it broke, their protection system failed to work. but it didn't break and all is well...i'd happily go about my business and just watch it in the future.

[MNAirHead]

On newer gear thermal protection will cut the power amp.. normally you can cycle through this many times before there's an issue.