Ok guys I was wacking through a new boot install today, which looks great, however I have a conundrum. I wish to have as little clutter in the boot as possible, so I'd like to mount my new amp and crossovers for splits on the boot lid.

Now I've seen that a people have mounted **** on their lid, most notably a guy going round here with an amp and some Focal 3 ways. Therefore I know this is possible.

So if anyone has any pointers on how to go about it, that would be great. I have some ideas, but I know theres some car audio gurus out there, and maybe they can shed some personal experience on this question.

Thanks guys,

Daniel

dont think its a good idea mounting any amp upside down
best off just making up some side panels for it
oh and the member your talking about only has the speakers in the bootlid not a amp

Its a massive amp, I just don't think side panels are gonna cut it.. :P

But I don't think it being upside down will have any affect on it, its still venting into space.

Oh here it is scroll down to benjames. Amp and speakers. Looks nuts.

http://www.aussiemagna.com/forums/showthread.php?t=49740&page=2

an amps heatsink is on top of the amp because hot air rises, when you mount it upside down the heatsink becomes the base of the amp, and the hot air dissipates into the circuit board. plenty of people have mounted them there fine, and many people have killed amps doing it. all depends on the install and the amp, personally i would play it safe and not risk it in the first place.

but if you do so feel the need to do it, first mount a solid piece of 16+mm mdf to the lid very securely as to prevent resonance, and mount the amp to that.

an amps heatsink is on top of the amp because hot air rises, when you mount it upside down the heatsink becomes the base of the amp, and the hot air dissipates into the circuit board. plenty of people have mounted them there fine, and many people have killed amps doing it. all depends on the install and the amp, personally i would play it safe and not risk it in the first place.

but if you do so feel the need to do it, first mount a solid piece of 16+mm mdf to the lid very securely as to prevent resonance, and mount the amp to that.

Food for thought, thanks for comments :)

Now assuming I'm going ahead with it, how in the hell will I mount the MDF to the lid... thats the problem I face? I'd prefer not to go drilling willy nilly, as rather not have speed holes in my lid.

EDIT: If anyone has side panel templates for a TF boot, care to send them to me? Just in case I change my mind.

You could bolt it to the lid reinforcment.

A few little bolts around the edge should do the trick, just make sure you leave enough cable on the amp so that you can open and close the lid with no problems, could be an idea to secure the cables (cable ties?) to the MDF board to stop strain on the amp terminals as well.

If you want to mount an amp upside down make sure its a next generation digital amp, like the alpine pdx series or blaupunkt similar offering these amps can be mounted anyware due to their "NIll" heat efficiency meaning these things don't produce much heat.

ok, be prepaired for a fair amount of work, i added just speakers to mine and it was a lot more work than i previously thought, i suggest do a fake boot floor and mount it flush, as that wont take up any boot space, if u do decide to do it, add some speakers, i think an amp would just look silly

http://i304.photobucket.com/albums/nn177/lowridermagna/21042008.jpg

So much bawwwwing about mounting amps upside down... People say the same thing about having them in an enclosed carpet box. I do it, and I don't have a problem with it either, no issues with heat in Townsville weather at all.

From what I remember of Ben's bootlid, it's just bolted into the ribbing on the bootlid... Not rocket surgery :)

If you want to mount an amp upside down make sure its a next generation digital amp, like the alpine pdx series or blaupunkt similar offering these amps can be mounted anyware due to their "NIll" heat efficiency meaning these things don't produce much heat.

alpine PDX are renowned for their substantial heat output actually. the first releases were the worst for this, but the ones sold today still carry on the same trait. mostly due to the fact that they have no heatsink at all, but also due to the power transfer through such a small footprint i guess.

Lucifer, while it may be fine for some, it may not be fine for others. it all comes down to the individual situation.

Magnatised, what kind of amp are you looking to mount anyway?

alpine PDX are renowned for their substantial heat output actually. the first releases were the worst for this, but the ones sold today still carry on the same trait. mostly due to the fact that they have no heatsink at all, but also due to the power transfer through such a small footprint i guess.

Lucifer, while it may be fine for some, it may not be fine for others. it all comes down to the individual situation.

Magnatised, what kind of amp are you looking to mount anyway?

x2 for the Alpines amps. Those older MRD-1001 and newer 1005's get extremely hot for a 75-80% efficient Class D amp. They just don't like to work, just like me :bowrofl:

Woob is right, comes down to individual situations, my Audisons get bloody hot in summer and if I run it full pelt in 40deg heat for about 40mins the bigger amp shuts down. But how often does that happen....

Not rocket surgery :)


or brain science

I would screw/bolt a piece of carpeted mdf to the lid, and use your self tappers into the mdf for your amps. Dont expect the elec boot opener to work anymore.

Not rocket surgery :)



or brain science

I lol'd :bowrofl:

I rekon it would look pretty spun out with it on the boot :) one of my concerns is how is it going to handle the constant bonnet closing. You will have to remind your self not to shut it to hard or it could damage it.

Another tip would be to remove the boot lid and turn it upside down. Would make things easier when working on it.

alpine PDX are renowned for their substantial heat output actually. the first releases were the worst for this, but the ones sold today still carry on the same trait. mostly due to the fact that they have no heatsink at all, but also due to the power transfer through such a small footprint i guess.

Lucifer, while it may be fine for some, it may not be fine for others. it all comes down to the individual situation.

Magnatised, what kind of amp are you looking to mount anyway?

Dude you are so wrong!!!! both the alpine and Blaupunkt won design awards for their 2007-08 offerings mainly do to high power with nill to no heat output.... please get your facts right before blurting them around.

If you can find proof that these amps produce high amount of heat or are unstable upside down or in "unconveintnal mounting" then please correct me otherwise please don't knock good gear.

hoon mate, i tend not to knock equipment, and i would barely say that having heat output is knocking it.. im not bias towards anything so ive got no reason to.

I'm running off the experience of ones that i've toyed with, and reputable audio installation companies comments about them. Sure the heat production may be lower than other amps (thus the award), but due to the footprint and lack of heatsink, the dispersion is not so successful.

With this said, Alpine wouldnt sell them if the heat was going to be an issue.. they are built to run hot.

Maybe before flaming someone for 'incorrect information', you should think about the fact that their may be some truth in their madness? The last thing i would like to do is give false info. I pride myself on being able to deliver helpful and knowledgeable info when needed, and if I am unsure on something I will either research it, or not bother inputting advice.

Thanks for your concern though, maybe next time it will be a little better placed.


Btw I never said anything about mounting them upside down, I was merely correcting your statement that they output 'nil' heat. Consider this, an amp would have to run 100% efficiency to have NO heat output. most class D amps round around 86% or so efficiency in a much larger chassis for the power offered. They also tend to offer a substantial heatsink to keep things cold. Given these features, generally they tend to get 'warm' without getting hot.

Now consider that the PDX would probably run at around a class leading 90-92% efficiency, and all that power is crammed into a really small space, meaning less area of heat dispersion. Now consider that the amplifier has no heatsink to transfer that heat. Even with a fantastic operating efficiency, it cant just defy the laws of physics. Wasted energy = heat, small surface area = less dispersion, and no heatsink = no transfer.

You do the maths, theres your proof.

Now consider that the PDX would probably run at around a class leading 90-92% efficiency, and all that power is crammed into a really small space, meaning less area of heat dispersion. Now consider that the amplifier has no heatsink to transfer that heat. Even with a fantastic operating efficiency, it cant just defy the laws of physics. Wasted energy = heat, small surface area = less dispersion, and no heatsink = no transfer.

You do the maths, theres your proof.

http://www.mobileelectronicsnews.co.uk/index.php?option=com_content&task=view&id=175&Itemid=

300w amp is probably running at 90% = 30w heat, about the same as a 33w lightbulb (10% efficiency).

Or I could be way off. Either way, no amp, or electrical device I know of has 100% efficiency, so there must be some heat loss somewhere. Mounting upside down on a boot lid could be fine, if there's air or material for the heat to dissipate to.

Hoon mate, perhaps you should feel the mono's after they been running for a while. 2 of those mono 1000WRMS PDX things running a type X each got very hot ( was in a boot of a golf - i.e very well ventilated ).

While nowhere near as hot a normal Class D MRD or similar but still hot none the less. I think someone is riding Alpines nuts a little to much.... With S/N of CEA2006 78db on the PDX2.150and all power rated @ 14.4v 1%THD... I suppose good an accurate way to describe it.

Ill put it simply for you. If you put your dinner in the oven, nice small confined space, it will stay warmer longer than if you leave it out on a bench. Then if you where to add a fan, it would get cooled quicker. Take a step back and think of it from a common sense point of view.

Haha such an interesting turn of topic :P

Thanks for all the insight guys, but I've managed to find some room on my sub box, so it'll be 3 amps easily mounted on the one box.

So just one more questions... crossovers on the sub box as well (to bring them closer to amp).. yay or neigh? Will the vibrations kill them?

I believe I do owe an apology and ironically I am not a massive alpine fan but my pdx5 is great and doesn't run hot etc... the nill heat was an exageration and assumed it would be treated as such. anyway I just a little pieved as these are great amps and maybe not getting their cudos. I much prefer the Blau range but you just can't get them!

Hey ya'll! Just an insight on how I managed mounting the huge amp on my previous install...

The install of the boot took a little over 2 days, and wasn't that hard to do. I mounted a piece of MDF using screws into the boot famework which worked out to be easy and quite sturdy, however if I was to do it again, I would have used a bit of car bog plugged into the boot framework which would have been even more supportive.

The amp I used on teh boot lid was a class A amp which had an efficiency rating of less than 60%. It did however have an internal fan, which helped dissipate the heat whilist it was mounted upside down. Bear in mind that I am in Townsville, and it was summer when the install was done, and I had no heat issues at all. If you are worried about heat dissipation, then you can mount a dedicated cooling fan beneath the supporting brace (piece of MDF) directly beneath the amp. I considered using an extra cooling fan, but it didn't seem neccessary after the install was done.

You can fit a fair whack of stuff into the bootlid if you spend a bit of time working out the placement of the various components, with relation to the boot framework. I ended up having just enough space to mount a 650WRMS class A amp, 2 three way crossovers (hidden) and a 3 way speaker setup with the correct space required for the 6.5" woofers to work properly, so it can be done.

The biggest problem you face with mounting all of this stuff is that the bootlid will become heavy. Very heavy. May I suggest you source 2 "1998 Mirage" bootlid hatch struts which will cost around $30 at the wreckers. They have a threaded nut on one end which you can tap into the TF bootlid hinge using an existing hole (using a 10mm thread tapper), and the other end can be screwed into the wheel arch. Works perfectly...

Another thing you will have to consider is where to route the cable required for the amp, and the speaker wiring. I laid a set of RCAs, 2 4GA power cables and a remote wire along the boot hinge, hidden beneath a "sock" made out of nylon fabric. I would advise against grounding the amp to the bootlid, as the bootlid will not be a good enough groud on it's own, so a dedicated grounding cable must be made from the amp to the car chassis for a trouble free install. It's this factor which is often overlooked, and I've seen many bootlid mounted amps fail because they were incorrectly grounded. The amp will get hot due to the bad ground, and it will "seem" to be a heat dissipation problem.


Heat dissipation, mounting plate, weight compensation and cable routing. Once you work out these problems it'll be easy....

http://www.lavendergreenooaks.com/BEN/reduced%20lid%20pic1.jpg

But making it look good in the end.... well that's rocket science I'm afraid :badgrin:
Nah... Should be p1$$ easy.... Um... better source a spare bootlid just in case though..


:EDIT: Just noticed that you are now gonna mount the amp to the sub box instead.... That's soft man.... soft...

just a random tip of the day, your amp is only class A for about the first 15W. after that its class AB. but that is beside the point, its great to demonstrate what has been done in regards to boot lid installs and should give some insight into the potential that can be done. nicely installed :)

just a random tip of the day, your amp is only class A for about the first 15W. after that its class AB. but that is beside the point, its great to demonstrate what has been done in regards to boot lid installs and should give some insight into the potential that can be done. nicely installed :)

Thanks woob! We gotta get more ppl to show their installs on the sticky thread!!!


Incidently, when I tested (and tweaked :))the PPI A1000/2 amp (shown in previous pic), I found that it operates as class A up to 67-75WRMS (depending on frequency) per channel, which I think is fricken awesome!!! Truely a beautiful amp...Maybe y they cost so much, and why they predominently run hotter than most other amps on the market :(. Just sitting idle they get hot to touch.. awesome!!!:)

To be honest I only ran the bootlid mounted amp up to the speakers rated point, as the Focal splits would have been overpowered otherwise (having an RMS rating of 80 watts). Having the amp run a subwoofer may have created more heat....Hmmmm... food for thought I guess...

In order to *cheat* a bit, I tweaked the subwoofer amps, so the Darlington configured op transistors were right at there crossover point which turned them basically into class "B" amps (there is 4 pots within the amp which allow for easy tweaking), and the third amp (which was originally intended for one set of fronts) was tweaked to become a class "A" amp, and it kinda ran a bit hotter for it too :shifty:

I didn't hear much difference in quality for all of the mucking around that it was, but it kept me busy for a while I guess.