400+ overheated

[JeezyMcNuggles]

Whatch out! I'v used the SVT 4 for many years and it needs some nice cooling. With that rack I'm pretty sure you will face some overheating issues. I had an SKB rack at the time and did face some issues.
However, if you drill holes on its side, you should be good.
Also, if you don't use it in bridge mode, it should also be fine.

Yeah, I don't use bridge mode. At least, I haven't needed to yet. But, it says rocking for 4+ hours in this case. So, I think I'm alright.

 

[agedhorse]

Correct, simple as it is.

It’s not that simple.

Some SKB and Gator models have almost no side clearance, almost all flight case racks have ~1-1/4” of side clearance. This is the difference.

Cutting holes in the plastic racks with a heavy amp weakens an already weak rack even more.

 

[Ben Esparza]

My 400+ is not in a rack, just sits on top of the cab. One night, after the first set, it was too hot to touch. I shut it down so it would cool during the break. Before going back on, I had a look and found that the fan had been dislodged and had become disconnected. Not sure how it happened but it was a very simple fix. Have a look if that happened. Also, I'm sure you know it has an on/off or speed switch, can't remember. Have a look at that as well. Best of luck, love my Mesa!

What Acadian said. Also, because the amp is on the heavy side, adding a few more pounds for a wood, carpeted 6U rack shouldn't be too much trouble. I suggest a 2U, large grid vent rack above the amp (remember...heat rises) as well as cutting a round hole on the side of the case itself where the vent fan is located to aid in heat dissipation. Paint the exposed plywood with a few coats of flat black paint. You can cover the opening with an appropriate sized, round speaker grill for protection and aesthetics.

 

[Roland GR 88]

It’s not that simple.

Some SKB and Gator models have almost no side clearance, almost all flight case racks have ~1-1/4” of side clearance. This is the difference.

Cutting holes in the plastic racks with a heavy amp weakens an already weak rack even more.

^^^this^^^
SKB or Gator racks are not very sturdy. They rely on their lids to make a strong box and once they deform they become a real PITA. For a big heavy head get a big heavy rack with proper suspension/mounting. They’re not cheap but shipping that head anywhere and/or paying an out of warranty bill won’t be cheap either.

 

[Sparky Mark]

I wouldn't use a rack case that had plastic side handles for such a heavy amp. The racks recommended by Agedhorse have the type of handles you should be looking for. Some plastic handles are only secured with 4 pop rivets into thin ply.

 

[agedhorse]

What Acadian said. Also, because the amp is on the heavy side, adding a few more pounds for a wood, carpeted 6U rack shouldn't be too much trouble. I suggest a 2U, large grid vent rack above the amp (remember...heat rises) as well as cutting a round hole on the side of the case itself where the vent fan is located to aid in heat dissipation. Paint the exposed plywood with a few coats of flat black paint. You can cover the opening with an appropriate sized, round speaker grill for protection and aesthetics.

No need to cut a hole in the side if the rack is designed with normal clearances. The plastic racks have some models with almost no clearance because the inset handles push the side of the rack right against the side of the amp blocking the fan vent.

 

[baxter_x]

Yeah, I don't use bridge mode. At least, I haven't needed to yet. But, it says rocking for 4+ hours in this case. So, I think I'm alright.

If you don't bridge it, you are definitely fine.

 

[chris_b]

I had this problem with my 400+ but I caught it just in time. The recess on the handle of a 4U SKB case blocks the air flow because the fan is about 2mm away from the plastic. I took a knife and cut the recess out. No problem after that.

With such a large and critical cooling requirement I would say an amp should be designed with the air flowing from front to back. It would probably mean more than 1 fan but at least damage to the amp and tubes could be prevented.

 

[agedhorse]

I had this problem with my 400+ but I caught it just in time. The recess on the handle of a 4U SKB case blocks the air flow because the fan is about 2mm away from the plastic. I took a knife and cut the recess out. No problem after that.

With such a large and critical cooling requirement I would say an amp should be designed with the air flowing from front to back. It would probably mean more than 1 fan but at least damage to the amp and tubes could be prevented.

Actually, the amp pre-dates the “zero clearance” SKB racks. There isn’t a problem using standard ATA style racks because they have adequate clearance.

IMO, racks should be designed to address equipment that’s been on the market much longer than the racks.

There were also issues with these racks and early Crest and AB Systems/Intl. amps.

 

[beans-on-toast]

It is important to find the right case for your equipment. Cases are designed for applications. For instance, not all ABS rack cases are structural, there are weight specs and stacking weight specs. I have plastic SKB racks for outboard equipment, they are good for wiring to a patch bay and keeping dust out. They aren’t travel cases.

Not all plastic cases can tolerate high heat. Some racks have removable side ventilation ports. There are also 1U fan trays that circulate air within the case.

Fan tray.

 

[agedhorse]

I had this problem with my 400+ but I caught it just in time. The recess on the handle of a 4U SKB case blocks the air flow because the fan is about 2mm away from the plastic. I took a knife and cut the recess out. No problem after that.

With such a large and critical cooling requirement I would say an amp should be designed with the air flowing from front to back. It would probably mean more than 1 fan but at least damage to the amp and tubes could be prevented.

Actually, the amp pre-dates the “zero clearance” SKB racks. There isn’t a problem using standard ATA style racks because they have adequate clearance.

IMO, racks should be designed to address equipment that’s been on the market much longer than the racks.

There were also issues with these racks and early Crest and AB Systems/Intl. amps.

 

[CptnOblivious]

Actually, the amp pre-dates the “zero clearance” SKB racks. There isn’t a problem using standard ATA style racks because they have adequate clearance.

IMO, racks should be designed to address equipment that’s been on the market much longer than the racks.

There were also issues with these racks and early Crest and AB Systems/Intl. amps.

Do you think it's necessary to have blank spaces above or below to cool okay if there is proper clearance on the sides? Trying to keep as small possible. That case company you posted has different depth options which is pretty awesome.

 

[jjk2007]

I had mine in a 6 space SKB. I drilled a bunch of small holes around the handle area on each side. Seemed to help with the airflow and the rack held up.

 

[agedhorse]

Do you think it's necessary to have blank spaces above or below to cool okay if there is proper clearance on the sides? Trying to keep as small possible. That case company you posted has different depth options which is pretty awesome.

Nothing below is required (and the amp should be in contact with the bottom of the rack for structural reasons), the space above is optional, as long as the fan is set to high, it's not really necessary. It's not a bad idea if you were to include a rack mount tuner or compressor though.