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HOW HOT DOES YOUR CLASS D AMP GET ?
- Thread starter Makatak
- Start date
- Feb 12, 2006
- 61,070
- 5
- 221,138
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
If the chassis is sitting in the sun, the chassis can indeed get hot even if the amp is turned off. This, of course, is not a class D issue though.
I ran my GK MB500 for a few hours today and it got fairly warm but the fan still had not engaged. The amp was certainly not hot but it was warm and I was concerned that the fan had not kicked in. I touched the fan blades with a small object and it suddenly started up and the amp cooled off completely within a minute. Makes me wonder if there is an issue with my my amp as the fan didn't kick in until i touched the fan blades.
Gena-Benz Shuttle 6.0 - after two hours of playing at moderate volume it barely feels warmer than my hand when I touch it.
+1
It's possible that the amp has minimal heat sinking, and depends on the fan to at least stir the air in the chassis.
EA Micro300. I can barely feel any heat where some power supply components are sunk to the chassis, otherwise nothing.
My Phil Jones D-200 gets barely warm. Does not have a fan. As already said, check the fan.
Perhaps fan positioning, obstruction? or could cab ohms be a mis-match?
Place the Little Giant facing backwards in the 2nd half of your next gig, so you can check out the fan.
Are you using an extension mains cable, not fully unwinding it?
Are you using instrument cables instead of speaker cables between head & speaker(s)?
Perhaps fan positioning, obstruction? or could cab ohms be a mis-match?
Place the Little Giant facing backwards in the 2nd half of your next gig, so you can check out the fan.
Are you using an extension mains cable, not fully unwinding it?
Are you using instrument cables instead of speaker cables between head & speaker(s)?
Very comprehensive answer thanks . Using 2 8ohm 2x10 cabs so running 4 ohms w/speakon cables .
I think ive solved it , when you turn Ashdown LG`s on they should do a fan run up for a few seconds and then fan stops , this one doesnt and ive never seen the fan come on when in use either so maybe the thermostat or fan itself is shot , the bloody thing is near new so theres no reason why it should be but hey . ......taken it back to the dealer for repair so heres hoping , ill let you know . Thanks
BTW the fan is on the top of the amp on LG`s , not on the back like most other amps ...... just try not to spill my beer on it LOL . Only using it for home practice anyway .
After a three and a half hour gig my Shuttle 6.0 is always stone cold. I've even asked my bandmates to put their hands on it and they're shocked.
I'm using a [Invalid or Expired Link Removed] power amp, and I've never noticed it even feeling warm to the touch after a 4 hour show. The amp I used previously was a Carvin BX1200, and it would get rather hot (but never failed on me).
Well, in the absolute sense you are quite correct; The problem lies in how that heat effects other bits; Circuit designers normally work to keep temperatures to a minimum for multiple reasons, not the least of which is the effect that heat has on conductivity and peripheral componentry. There is a reason that old tube amps (which generate crazy heat, by nature) are built with LOTS of room for air to flow. Class D amps? Not so much.
I think the net-net is, if your amp is getting hot to the point where you're worried about other parts of your rig (or even injury), there is a problem, and it sounds like that's where the OP is at.
I know that after an evening of playing, my class A/B amp will get warm - but never hot.
of sorts......
I have had folks mention "gosh that amp got hot"..... and have actually checked the unit, finding that they were reacting more-or-less as "I would not like to shower in water that hot". meaning that the temp was perhaps 120F, which is 49C. Hot enough that the part should be shielded from contact, but not in the slightest degree hazardous to the circuitry.
My point is that "hot" is a matter of perception (literally ) and that we have NO IDEA how hot the unit really is.
it is IMPOSSIBLE to declare "there is a problem" without more info.
Now, if you have the same model, and you play hard and it stays stone cold, then that info is HIGHLY relevant in deciding if there is a problem, especially if someone else who has one confirms your statement. But we don't have that. We have testimonials about OTHER units.
What a different amp does is not relevant to the OPs possible problem, really, although it might be helpful in comparison. It might just be that the heat is directed elsewhere and not noticed on the other unit. or it might be that the other unit really IS much more efficient.
Having worked with innumerable good musicians (much better than me) and designed I don't know how many amps, I have learned a few things about what you hear said vs what is really happening. It is very relevant to the internet, where we NEVER see the actual item.
Component heating?
There are highly respected products (I don't want to name them) that I see many folks on here have, which cannot be run at full power for more than *5 SECONDS* because any longer will overheat a vital component....... No, I did not design them, never even worked for that company, but I think the product in question is quite good, as do thousands of others who use them.
