Mesa Boogie Walkabout Mega-thread Part 10

[gastric]

I'm not expert, but it sounds like a reasonable rig and setup to me. Thermal shutdown would likely indicate it's getting too hot. I'd start by looking at the fan and heat sinks to make sure they're clean and working properly. Take the top lid off during practice to see if that helps. Stick a regular room fan blowing on the amp, see if that helps. Basically isolate if it's heat / cooling related.

 

[honkimon]

I'm not expert, but it sounds like a reasonable rig and setup to me. Thermal shutdown would likely indicate it's getting too hot. I'd start by looking at the fan and heat sinks to make sure they're clean and working properly. Take the top lid off during practice to see if that helps. Stick a regular room fan blowing on the amp, see if that helps. Basically isolate if it's heat / cooling related.

I just got a new (old) one two weeks ago. What are the chances of this one having the same issue? Googling; walkabout overheat brings up very few hits. Seems like a pretty rare case and now I think I am leaning toward something else in my setup that may be causing this... like above fuzz... I'm thinking it's either the fuzz or something in the cabinet.

 

[sunbeast]

Definitely another cab will increase your headroom noticeably- probably moreso than a more powerful amp would (unless you start getting up into the 800-1000 watt range). The only concern there is making sure your total impedance isn't going too low. If your current cab is 4 ohms, then adding anything else will lower your total load below 4 ohms (another 4 ohm cab would give you 2 ohms and an 8 ohm cab 2.67 ohms). Given that you are already having overheating issues and are pushing your amp to the max, I wouldn't suggest running your amp below 4ohms personally, as the lower you go the more heat is an issue. So I would suggest either two 8ohm cabs or one large 4ohm cab. I use a 4ohm 6x10 with my Walkabout and can get very loud!

As far as fuzz- it isn't the fuzz itself that is an issue, just that it is pushing an amp that's already being pushed near its limits and probably masking some of the nasty distortion that clipping a solid state power amp can create. Also- feeding back and sustaining notes through an amp pushed that hard can definitely put a lot of stress on them- most bass amps are designed for dynamics (attack and decay), and sustained notes such as those made by synths definitely benefit from more clean headroom (as your amp has no chance to recharge and cool down in between peaks). Tube amps are usually designed more robustly as far as heat tolerance, so loud sustainy stuff is less potentially damaging through tubes (generalizing here).

 

[sunbeast]

It could be the cabinet- it just sounds more likely to me that it is the amp given your setup/settings and knowing that "Noon" on a Mesa Master Volume generally= full-on headroom-wise.

 

[ImTheOnlyOne]

Had the senseless urge to get another cab (love my pair of SVT-210AV's). After reading many comments, and especially those of Tom Bowlus, I decided on the Berg NV115. As expected, the single Berg isn't as loud as the Ampeg pair, but it is still plenty for my usual needs (I still have my SVT-VR/Berg NV610). However, if you already have the WA/210AV pair setup, I don't recommend getting the Berg; choosing which to use can be daunting.

Following two months in the shop, tomorrow I get by red face WA back with the full array of Mesa updates. Can't wait to plug in my 210av - then try the Powerhouse 210. With other heads I've liked the 210av so far, but no love there... yet.

 

[Chef]

I never had a Walkabout shut down on me; at 8, 4, or 2 ohms.
I never use effects.

Hello ladies and gentlemen,

I am back. I posted a on a couple of occasions about my WA going thermal and shutting down after about an hour of use. Being a busy dad who commutes and works long hours the only thing I really had time for was buying a new / used WA head. It's a newer silverface than my original. Either way, the new head is doing the same thing.

Let me spell out my signal chain:

Stingray bass > pitchblack tuner > EHX bass big muff > Prescription electronics Depth charge (fuzz) > Boss CE-5 (chorus) > Boss BF-3 (Flanger) > Walkabout active input > Powerhouse 410 (pre Player Control Network but still looks like the new models.)

I am in a metal / sludge / hardcore band. The gain is always about 1 oclock, the eq is flat, and the master is never beyond noon. I use fuzz a lot. My next rehearsal I am going to play sans effects and fuzz and see how that goes to maybe cancel out the possibility of it being the cabinet causing this to happen.

Just thought I'd give an update on my trials with the WA. I've had walkabouts sense 2009 and if I can't sort this out I may upgrade to the prodigy.

Have a great weekend!

 

[MuthaFunk]

I have had mine shut down on me once, I was running it maxed for two sets into a 410 cab and a 2X12 cab taking it down to 2 ohms. I also replaced the cooling fan with one that was quieter and lower flow. I was running plenty of fuzz and distortion that night.

I often ran my WA at 4 ohms into a 410 wide open or even 212 at 2 ohms (pre at 1:00 and master at 12:00) and I could never get it to shut down even with my lower flow replacement fan.

Something doesn't sound right with the head cutting out with a 410 at 4 ohms. I agree with sunbeast that it sounds like you need more cabs to achieve the volume you need. There are many that find the WA a little short on power when confronted with a loud drummer.

I think a matching 8 ohm powerhouse 210 to place on top of your 410 would get you more headroom and power out of the Walkabout at 2.6 ohms but the cooling system should be checked out before you do that or you'll just get more shutdowns.

Things to check, fan is rotating and clean, heatsink is free of dust, and no burnt components on the circuit boards. It's possible that something in the shutdown circuit has overheated and is now causing the thermal overload to trigger sooner than it should from the factory... that's kind of a long shot though.

Is the Walkabout racked by chance? What's the air flow like around it? Any gear sitting on top of it?

 

[StayLow]

"The gain is always about 1 oclock, the eq is flat, and the master is never beyond noon."

I've used that exact setting for gigs in hot rooms lasting hours, and never had any of mine shut down (I have three). Not even with cabs resulting in a 2.67 Ohm load. Mine also have a quieter fan, though the flow is nearly to spec. Oh, and in some cases the head is stuck in a combo cab so there's even less chance for heat dissipation.

I use a lot of effects regularly on one of these gigs, but not distortion/fuzz. I really can't see why the input would make any difference though.

Good luck.

 

[Rickles]

The fact that both WA's shut down seems to indicated it isn't the amps. Just my unknowledgeable two cents.

 

[Groove Doctor]

Use a HPF or EQ amp differently:
Low Semi-parametric -9dB @ 30Hz
Low Shelf EQ +6dB

Those low freqs chew up a lot of power. If you see your speakers moving then there's too much deep lows.

 

[U4EA]

Use quality speaker cords from amp to speaker, and from speaker to speaker. 14 awg (good), 12 awg, better. Keep spkr cords as short as possible.
Your effect or amp may be trying to pump out too high a bass signal which will put a significant strain on the amp.

 

[MuthaFunk]

The fact that both WA's shut down seems to indicated it isn't the amps. Just my unknowledgeable two cents.

True but it could be the way both amps were mounted. If there's not enough room for heat to escape...


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[sunbeast]

"The gain is always about 1 oclock, the eq is flat, and the master is never beyond noon."

I use a lot of effects regularly on one of these gigs, but not distortion/fuzz. I really can't see why the input would make any difference though.

Good luck.

The input decides the output- the same way that putting a hot active bass into the input will overdrive the front end much sooner than a low output passive bass, it also pushes the back end more when you feed a gain stage a hot fuzz signal- the position of the knobs says nothing on its own (for reference I can fuzz out the input of my Walkabout using my Alembic-equipped bass with the Gain at only about 10 o'clock, or with my low output Ric I can crank it til 3 for similar gain).

 

[Rickles]

The fact that both WA's shut down seems to indicated it isn't the amps. Just my unknowledgeable two cents.

True but it could be the way both amps were mounted. If there's not enough room for heat to escape...


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I should have been more clear; I was thinking that both amps probably don't have the exact same internal problem, but something like your suggestion, the effects, or something else.

 

[honkimon]

No mounting is used with either WA. Whichever is in use merely sits on top of the ph410.

 

[EdwardofHuncote]

Been doing another round of A/B'ing this evening, trying to pin down this distortion... <snip> ...So this head is going on the Brown Truck tomorrow... see if the Petaluma amp elves can fix it up.

Updated - Just got a call from Rich at Mesa. My secondary Walkabout is fixed and on the way back.

The "dirty" sounding input gain midrang-ey distortion I had been hearing was determined to be a clip limiter setting out of spec. Also changed out one preamp tube for minor noise issues.

By happenstance, just today I picked up a Walkabout headcase to house this one in when it gets home.

 

[rodl2005]

I recently got a WA Scout 8 ohm cab to sit my WA in. I had one years ago but stupidly sold it.
Very glad to be back in the Scout fold again. Great sounding cab for low-med level use.

 

[vin*tone]

Where'd you get the 12 rod?

 

[EdwardofHuncote]

Got my repaired Walkabout amp back yesterday...

FWIW, I shipped this amp cross-country on 10/7, and it was done and on the way back in less time than the estimated three weeks. Thanks Mesa! :thumbup:

 

[rodl2005]

Got the Scout cab off a guy locally. He wasn't using the cab & just wanted his WA head. I was VERY happy to grab the 8 ohm Scout cab off him.