Most Durable HU

[EdMuse 10+ year member]

I'm still trying to get in touch with Pioneer to find out how hot they test their gear. I've thought of using a computer case-style fan. I'm worried that it will just blow hot air all over my stereo. I figure if Volvo couldn't efficiently duct the hot air away, I probably can't. Also, it would have to be a 12-volt fan.

You may note that I've been thinking about this for a while.

-EdM.

Look at any Pioneers? My pioneer is directly under 2 vents in my chevy beretta. In fact the trim piece that you have to pull out to install/unistall the stereo has the 2 top vents built into it.
An idea I just had. If you look at like 8mm computer case fans...

 

[EdMuse 10+ year member]

what the eff are you talking about?

My interpretation is that he means that, if I got a stock HU, it would be built to handle the heat of the car it was put in. Actually, Volvos had an external amp as well, so power isn't an issue with the stock stereo. The only reason I replaced mine was that it wasn't working when I got the car. Problem is I've never seen one with a CD player. It's a 1990 Volvo 240. I don't think CD players in cars were all that popular yet at the time. And they stopped making the 240 series in '93.

-EdM.

 

[EdMuse 10+ year member]

judgeing by his first post, i doubt hes using an aux amp

Originally Posted by SirSyko

Get a deck with the option of the internal amp to turn off. Mine does this.

True. Actually, I removed the stock Volvo external amp when I put the Blaupunkt HU in. I don't know how much power it was pushing, but I figured any decent aftermarket unit would do better without the external amp. Besides, it gives me more room to work behind the dash (although I'm not much into high end car audio, I've done a fair bit of modding in terms of putting in guages and such; it might be a sedate family station wagon, but I gotta have a five-speed and a tach at the very least).

What I'm not getting, though, is how having an external amp will help me. Sure, the HU itself will run cooler, but the 150 degrees behind the dash, just from the heating system is hotter than the ambient temperature ratings of an Aiwa (112), an Alpine (140) or a Kenwood (140).

-EdM.

 

[VOA_NIGHTMARE 10+ year member]

just try one of the higher end hus like i mentioned I used. Believe me mine rests on top of the vents and gets so hot you cant even take a cd out some times. I am a cook so my hands can take some heat and i mean these are hot for me to touch.

 

[fatryan 5,000+ posts]

Beacuse it's not quite that simple. If it were, I would have done it originally. The problem is that there isn't enough space between the ducts and the bottom of the headunit's sleeve to get any decent insulation in there. There is, perhaps, 1/8" of clearance. Now, if you could suggest to me a material I could use that will provide enough insulation in that small amount of space, I would rip the dash out of my car to get it in.
Recommendations?

-EdM.

oic. hmmm. thats a tuffy. maybe throw some tin foil around the ducts. it will reflect some heat, maybe not much, but some. see if you can find some kinda compressed insulation at home depot or lowes

 

[fatryan 5,000+ posts]

Originally Posted by SirSykoGet a deck with the option of the internal amp to turn off. Mine does this.

True. Actually, I removed the stock Volvo external amp when I put the Blaupunkt HU in. I don't know how much power it was pushing, but I figured any decent aftermarket unit would do better without the external amp. Besides, it gives me more room to work behind the dash (although I'm not much into high end car audio, I've done a fair bit of modding in terms of putting in guages and such; it might be a sedate family station wagon, but I gotta have a five-speed and a tach at the very least).

What I'm not getting, though, is how having an external amp will help me. Sure, the HU itself will run cooler, but the 150 degrees behind the dash, just from the heating system is hotter than the ambient temperature ratings of an Aiwa (112), an Alpine (140) or a Kenwood (140).

-EdM.

oh, well if the 150 is JUST from the heating system then an external amp prolly wont help. i (and i assume the others) were under the impression that was the temp with your current deck installed and running.

 

[UPCguy 10+ year member]

Could he perhaps wrap the ducting of the heating system in some kind of thin insulation? I know my dad is in contracting, and sometimes that is done with water pipes to hold heat in and stop them from freezing. I don't know if you would like start a fire or something though. Maybe see if you can find something that is high temperature rated and fireproof/fire resistant, just to be sure. Lol

 

[UPCguy 10+ year member]

Oh one more thing, I asked my dad about that, if there was something you could do. He said that he does not think a heating system would run that hot, and if it did, it would burn you. He's worked on cars and things before, he used to be a bigger car buy back with the older muscle cars in the 70's. But what he said is that your car's electrical system may be different. Basically that your Volvo may use a negative ground as opposed to the regular ground, and that when you hook your units up, you may be hooking them up wrong, and that doing that fries them. So take that for it's worth, maybe it's an idea that will help?

By the way, on the fans, if you did that, maybe you could direct the air into the lower cabin of the car? Like onto the floor, or somewhere else, maybe back into the ventalation system?

 

[EdMuse 10+ year member]

Could he perhaps wrap the ducting of the heating system in some kind of thin insulation? I know my dad is in contracting, and sometimes that is done with water pipes to hold heat in and stop them from freezing. I don't know if you would like start a fire or something though. Maybe see if you can find something that is high temperature rated and fireproof/fire resistant, just to be sure. Lol

Nothing's gonna burn in there. I mean, we think of paper as being pretty flamable, right? Its flashpoint is 455 degrees F. Alcohol doesn't even boil until 168 degrees F. So, I'm not worried about anything flaring up at 150 degrees F. My problem is that I just haven't found a suitable insulation. I don't think aluminum foil alone will do it, as metal transmits heat too easily. I was thinking about foil-faced plywood panelling, foil side down, but that seems pretty cheesy. I figure there must be something better.

Also, it might be academic, depending on what I use, but I'm trying to consider also whether I should insulate the ducts or the HU. If I find something to wrap around the ductwork, the hot air will be going where it's supposed to go: out the vents. If, for instance, I surround the HU underneath and on the sides, and route this sort of "trench" of insulation back to the vent in the dash, that would keep the hot air out of the area of the HU, while allowing the hot air produced by the HU itself to vent. Still, the two are so close together that I may not be able to do one without the other.

-EdM.

 

[DBfan187 5,000+ posts]

aluminum foil reflects heat, not transmit.

 

[EdMuse 10+ year member]

Oh one more thing, I asked my dad about that...He said that he does not think a heating system would run that hot, and if it did, it would burn you.
...But what he said is that your car's electrical system may be different. Basically that your Volvo may use a negative ground as opposed to the regular ground, and that when you hook your units up, you may be hooking them up wrong...

Volvos are made in Sweden (or at least they used to be). It gets pretty cold there, so their heating systems tend to be pretty good. Even with the heat cranked, it ends up being cooler by the time it difuses out into the cabin. Still, I keep the heat slider about a finger's width from minimum in the winter, and that's warm enough. It might make sense to point out that I used a meat thermometer to check the temp, and they are designed to be imersed in whatever they are measuring, so it's possible that it's even hotter in there. That's why I'm worried about getting anything expensive, for fear it will fry, too.

As for grounding, I'm not sure what you mean. Negative ground is "regular ground." I don't know if I've ever had a positive ground car (the only other option). Ford did it in the '40s, and MG was the last car company I know of that did positive ground systems in their cars, and that was in the '60s. I had a '64 MGB, and it was negative ground, though it may have been converted.

Pardon me for engaging in my vocation as teacher, but allow me to explain that there are two ways to hook up the electrical systems in a car, the difference being which battery terminal is connected to the bodywork. In a positive ground system, the + terminal is connected to the bodywork, so the power flows out through the bodywork into the wiring for any component in the car. Then, wiring harnesses carry the flow of electrons back to the - terminal.

The other, more common way to do it is to have the wiring harnesses carry the flow of electrons out from the + terminal of the battery to the components, then they flow back through the bodywork to the - terminal.

Thus, in either case, the components are grounded to the bodywork, but in a positive ground system, the bodywork is hooked up to the positive terminal, and in a negative ground system, the negative terminal is. And, as I mentioned, negative ground is far more common overall, and currently, I can only imagine, universal. Besides, if you have a car which uses one system and a stereo which is made for the other, for instance an old, positive ground Jaguar, MG or Triumph, and a modern, negative ground stereo, then, at best, the stereo will just not work, and at worst, it will explode in a lovely shower of sparks. What fun!

So, since my stereo still works, marginally, that can't be the problem.

-EdM.

 

[DBfan187 5,000+ posts]

AFAIK, in a DC circuit. Electrons flow from Negitive to Positive.

 

[EdMuse 10+ year member]

aluminum foil reflects heat, not transmit.

Try this: put a piece of aluminum foil on a stove. Put your hand on the foil. See if the heat gets through.

Now, try this: take a foot long piece of foil and twist it into a foot long "stick." Put one end on a hot stove. Try to touch the other end and see of it is hot.

Any material will absorb and transmit a certain manount of energy at a certain rate, and reflect a certain amount of energy. Metals absorb and transmit heat quite well. Aluminum foil is good for two reasons: it's reflective, so it does reflect more heat energy than it would if it weren't, and it absorbs heat quickly, so it releases that heat quickly as well, so if you heat it up, it cools quickly as well. But if it only reflected heat, people would be wrapping their houses just in foil, and not in foil-backed fiberglass.

Since aluminum foil absorbs and releases heat so effectively, the foil wrapped around my ductwork would quickly rise to 150 degrees, then dump the heat into the dash. Whatever I decide to insulate with, I'm sure it will involve a coiating of foil, but I don't think foil alone will do the trick.

-EdM.

 

[DBfan187 5,000+ posts]

I didn't say it wouldn't work, it just reflects heat better.

 

[UPCguy 10+ year member]

Well, if you are sure it's heat, I would say wrap the duct in the insulation, not the head unit. Because my thinking is that the insulation holds heat in. Like you notice for with a lot of electronic units, look at tops of computer monitors, etc. Most anything electronic has slits or vents of some kind so that heat can get away from the circuits. When you deal with a computer, heat will fry a computer if you let too much get to it. So you put fans and what not in there to pull that heat off. You will probably increase the temp of the head unit if you wrap it in insulation. Could you get some kind of thin insulation to wrap your ducting in and then maybe rig a fan or 2 behind the head unit to pull heat from off the unit? Just some ideas.