ADA Depot - A Forum To Support Users of ADA Amplification Gear

Please login or register.

Login with username, password and session length
Advanced search  

News:

Lets get Technical > All Things Tube All about preamp and power amp Tubes.

Pages: [1] 2   Go Down

Author Topic: Overheating  (Read 7625 times)

0 Members and 1 Guest are viewing this topic.

rickeb1

  • Full Member
  • ***
  • Offline Offline
  • Posts: 113
Overheating
« on: Time Format »

I just played a gig yesterday with my very small "B" rig which consists only of an MP-2 and an old Carvin DCM150 power amp.  These are housed in one of those 2-space padded rack bags which are very shallow, just enough space in back to close behind the units.

I'd played a few gigs with this setup previously, and all went well.  At yesterday's gig, we played outside in the sun, and it was very hot and humid.  About half way through the first set, my amp started sounding weird.  It seemed to lose all body, and had only a very harsh high-end.  I remembered reading about something called "thermal distortion", and guessed that something was overheating.  When the set ended, I grabbed a screwdriver and took the units out of the rack and placed them on top of the rack (back-to-back since I had only a short cable to connect the two), hoping that the added ventilation might solve the problem.  And it did seem to work, as I didn't get that weird tone the rest of the gig.

I'm wondering what I might do to ensure I don't have such a problem again.  I'm assuming the problem was in fact overheating, caused by the direct sun, high temps and humidity, and the close, tight rack enclosure which offers virtually no ventilation.

First, which piece do you think was the main source of the problem, the MP-2 or the power amp?  If I bought a different rack case, say a 3-space one and put one unit on top and the other on the bottom with a blank space between them, would that likely do the trick?  Or maybe another 2 space rack (I'm trying to keep things as small as possible) that is deeper, allowing more air?  Maybe a fan of some kind?

Thanks for your thoughts on this!

~Rick

Logged

Harley Hexxe

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 1965
Re: Overheating
« Reply #1 on: Time Format »

Hey RickeB,

    A fan is always a good idea in a rack. I like my rack cases with front and rear rails because I can mount rack panels with fan cutouts in the back and place them where they need to direct air the most. I don't space my rack units apart, so it was planned that way.

     Harley 8)
Logged
I only have two brain cells left, ...and I'm saving them for the weekend!

rnolan

  • Administrator
  • Superhero Member
  • ******
  • Online Online
  • Posts: 5998
Re: Overheating
« Reply #2 on: Time Format »

Hey Rick, what a bugger... Was the DCM150 hot when you took them out ?  MP2s get very hot and IMO need a little air around them, my guess is that's where most of the heat was coming from (apart from the sun), not sure of the symptoms though, where the bad sound was coming from, maybe the amp ? I've never had that with a MP2 but then I've never put mine quite in that situation (padded bag/rack, sun).
You should be ok with a 2RU normal rack (skb, gator etc). I put my MP2 at the top as then there's a reasonable gap (~3/8" ish) above it for the heat to dissipate.  The MP2 is quite a deep unit.  I've been looking at racks lately and there seems to be 3 common depths:
Shallow - 10.7" (27.48cm)
SKB ATA cases - 15.94" (40.48cm)
Deep - 17.6" (44.7cm)
The SKB ATAs are the perfect depth, the shallow may not close on the cables comfortably ?? and also has no room for a power board and the deep ones are way to deep.
A 3RU would be nice and give you a space for a multi FX, but then why not 4RU (space for a B200s LoL).  My feeling is the padded bag/racks are more designed for low power SS gear, not tubes.  With a decent rack you shouldn't need a fan, but it can't hurt, mounting it is another story...or buying a rack with a built in fan $$$ ??
Logged
Studio Rig: Stuff; Live Rig: More Stuff; Guitars: A few

MarshallJMP

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 4702
    • marshalljmpmodshop.net
Re: Overheating
« Reply #3 on: Time Format »

Like R says,those MP-2 get hot after a while so I also have a fan in my rack because else it will overheat.
Logged

rnolan

  • Administrator
  • Superhero Member
  • ******
  • Online Online
  • Posts: 5998
Re: Overheating
« Reply #4 on: Time Format »

Hey MJMP, have you ever had a MP2 overheat ? does it go all thin etc like Rick is describing ?
I think the only thing I've got that gets hotter than the MP2 is the B200s, you can cook your breakfast on it...
Logged
Studio Rig: Stuff; Live Rig: More Stuff; Guitars: A few

MarshallJMP

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 4702
    • marshalljmpmodshop.net
Re: Overheating
« Reply #5 on: Time Format »

No that I have not but it warms up my MP-1 and it will give me a gain loss. So I put a fan in front of my rack and it stays very cool. But I also have 17 units in my rack so there's some heat inside. That's why I don't like to put in a power amp, IMO best is to put power amps in a different rack.
Logged

rabidgerry

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 2105
  • HEAVY METAL
    • Rabid Bitch of the North band facebook
Re: Overheating
« Reply #6 on: Time Format »

I have not encountered this yet but last few shows I noticed my rig was warm and as a safe guard I would like to know how prevent the situation before it happens to me some day.

How do you get a fan inside your rack without causing noise?  What size of fan?  Are their special rack fans?
Logged
"whadda ya want? we want Heavy Metal"

Guitars:1986 Westone Dimension IV, 1989 Korean Squier Fat Strat Silver Series, 1998 Korean Squier Fat Strat, MIM Fender Fat Strat - FR, Squier Stagemaster Deluxe - Thru Neck x 2, Squier Stagemaster 22 Fret - 1st Gen, 1999 Squier Showmaster - Anniversary Edition, Squier Showmaster, Tokai FV40 Flying V

Effects:  Ada Mp1, Peavey Rockmaster, Boss GX700 Boss SX700 * Amps:   Rocktron Velocity 300 - Koch ATR4502 - Peavey Classic 50/50
Cabs: 4 x Bugera 2 x 12"
Midi Controller: Behringer FCB1010

MarshallJMP

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 4702
    • marshalljmpmodshop.net
Re: Overheating
« Reply #7 on: Time Format »

http://rackfans.com/

Here you can see rack fans, but you could make something yourself.
Logged

Kim

  • Administrator
  • Hero Member
  • ******
  • Offline Offline
  • Posts: 842
  • If it's too Loud...you're gonna get more of THAT.
Re: Overheating
« Reply #8 on: Time Format »

Don't overlook the simplest solutions.   :banana-skipping-rope-smiley-e

You could always just use a normal BOX FAN and position it somewhere close behind your rack, blowing into it or up at it.   The rackmount fan might be better only because it stays with the rack after installation, but a good box fan works very well.  They are usually inexpensive in "big box" stores.... and you might already have one or two of these already!   While they're fairly quiet, you might not want them in the studio.  Onstage will be just fine though.
« Last Edit: Time Format by Kim »
Logged

Soloist

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 534
  • Take No Prisoners...Take No Sh!t
Re: Overheating
« Reply #9 on: Time Format »

I just use one of these cheap clip fans. Clip it in the back of the rig, plug into the furman. Nice and cool!
Logged
Live Rig:
Fractal Audio FM3 ver 1.06
Boss GT 100 ver.2.11
Switching- Radial Engineering Big Shot I/O v2 - Radial Engineering Pro D2 Stereo Direct Box
Power - Live Wire Power Conditioning Distribution System
Monitors  - (2) FRFR-112 Headrush Stage monitors
Axes - Charvel So Cal Pro Mod-Jackson DK2MQ Pro-Jackson USA Soloist-Ibanez RG3XXV
ADA gear: MP1- MP2 - MT200
Studio gear- way too much to list.

Griphook

  • Full Member
  • ***
  • Offline Offline
  • Posts: 215
  • Less is more? More is more!
Re: Overheating
« Reply #10 on: Time Format »

I'm planning on getting some PC-Fans. And then just plugging them into a 12V DC Wall-Wart
Some of them are pretty silent but still have a decent air flow.

On my PowerAmp (Brunetti Rockit)I replaced the original fans with Noctua Fans. Much more quiet and better cooling :thumb-up:
Logged

MarshallJMP

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 4702
    • marshalljmpmodshop.net
Re: Overheating
« Reply #11 on: Time Format »

For the moment I'm also using a box fan, but in front of my rig and it works very good.
Logged

Harley Hexxe

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 1965
Re: Overheating
« Reply #12 on: Time Format »

I use those clip on fans in the back of my tube amps. That helps the air flow in the old Fender Twins :thumb-up:

     Harley 8)
Logged
I only have two brain cells left, ...and I'm saving them for the weekend!

rickeb1

  • Full Member
  • ***
  • Offline Offline
  • Posts: 113
Re: Overheating
« Reply #13 on: Time Format »

The clip-on fan seems like a great idea (and inexpensive :) )!  Thanks for all the discussion!
Logged

rabidgerry

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 2105
  • HEAVY METAL
    • Rabid Bitch of the North band facebook
Re: Overheating
« Reply #14 on: Time Format »

The clip-on fan seems like a great idea (and inexpensive :) )!  Thanks for all the discussion!

I too second the clip fan idea.  That's a superb solution Soloist.

One would do me right?  You power it of you Power Conditioner?

I see one on shebay for £9.99,  that a good or bad price?  That's $13.
Logged
"whadda ya want? we want Heavy Metal"

Guitars:1986 Westone Dimension IV, 1989 Korean Squier Fat Strat Silver Series, 1998 Korean Squier Fat Strat, MIM Fender Fat Strat - FR, Squier Stagemaster Deluxe - Thru Neck x 2, Squier Stagemaster 22 Fret - 1st Gen, 1999 Squier Showmaster - Anniversary Edition, Squier Showmaster, Tokai FV40 Flying V

Effects:  Ada Mp1, Peavey Rockmaster, Boss GX700 Boss SX700 * Amps:   Rocktron Velocity 300 - Koch ATR4502 - Peavey Classic 50/50
Cabs: 4 x Bugera 2 x 12"
Midi Controller: Behringer FCB1010
Pages: [1] 2   Go Up