power amp up side down

[Rob_Beech]

I've got a Matrix STR1500 that only works upsidedown. Luckily it isn't I hire stock, infact I really ought to fix it and sell it.

 

The heat SHOULD be the only thing that plays a part here, it might not be, but it SHOULD.

 

 

Rob

[Sirch Sound]

It should also look tidy from the outside and mounting an amp upsidedown will detract from that quite severely.

 

Very true, but I think thats the least of his woried, when there could be neumerous other problems which could effect the performance of the amp

 

Rich

[Bobbsy]

Go on, I'm curious. Why would inverting a 2500 make any difference, the outputs on mine are verticaly alligned and centeral so inverting them would make no difference. Other than moving the inputs to the right, for this reason?

baz

 

Hi Boogie Man. I was the mod who added the note to your post and apologise if I mis-understood your question.

 

However, in my defence, may I say that, even on re-reading your post this morning, it's not entire clear whether your phrase "make a difference" refers to the advice given not to invert it or to the wiring/rear panel layout. I took it as meaning the former; you obviously meant the latter.

 

In my additional defence, it was late at night here in Aus...your post was the last thing I read before bed!

 

Anyway, sorry for the misunderstanding.

 

Bob

[The Boogie Man]

Hi Bob,

As you must never tire of hearing it, Usually in a bad accecnt, "no worries mate" ;)

Baz

[pisquee]

Have you tried contacting Behringer on this one?

 

If you do go ahead I would advise some extra cooling to draw hot air out of the upside down amp quicker, incase the internal air flow/cooling is affected.

[palbin]

Hello!

 

They simply had to go upside down (I have two of them) not to spoil my wiring - now

jacks for signals, speakers and power on the back as well as control buttons on the front conform with my twelve other amps which I like being a bit of detail-man and which is also important not to have to mix signals cables with power ones etc. - I simply

removed all fabric labeling on the units and replaced them with my own so that it now

requires a very close inspection to realize they are upside down - only thing is that bridge mode is the right-most channel (which I have marked as a precatution). Should

the amp not like their new positioning in the long-term run (which doesnt seem complet-

ely unlikely as I have heard people say you have to be nice to the Behringers) they have to go to the bin instead!

 

Thanks for the advice, best palbin

---

PS. I didn't ask Behringer as they (wisely I guess) tend to not answer when you get too

unusual in your quiries, and as it then seems unwise to wear them out with too many

such quizz perhaps risking to also have my more mailline sort of quiries answered! DS.

[Sirch Sound]

If you have go for this solution may I reccoemnd some sort of external cooling? You can buy 19" rack panels with twin fans in from the usual suspects, and if you have a proper amp flightcase, I.e rails on the back and front, then you should be able to bolt this onto the back of the rack. It might just do the trick for the cooling.

 

Rich

[Bobbsy]

Moving this slightly away from the original topic, this issue of varying locations for connectors is one that occurs in any rack installation. If you ever look in the back of the racks in the "Central Apparatus Room" or "Machine Room" at a major TV facility, you'll see that the location of mains, video ins and outs, audio ins and out and various data cables jumps all over the place from one piece of gear to another.

 

In a big facility, turning one or two items upside down is no real solution. What does help is the skill of the "wireman" who's putting it all together. Neat cable looms (but long enough to get the gear out for servicing) are truly a joy to behold--and doing them is a major skill. Mains leads tend to be tied to a cable tray up one side of the rack; signal and data (logically grouped) tend to go up the other.

 

No, I can't do this myself. Despite numerous attempts to emulate their style, my attempts look like spaghetti compared to the real masters.

 

Anyway, I'm sure that is of no help at all but I just thought I post my tribute to the wiremen of the industry!

 

Bob

[Al Cain]

How goes the rack? any problems yet??

 

Alex

[Sirch Sound]

In a big facility, turning one or two items upside down is no real solution. What does help is the skill of the "wireman" who's putting it all together. Neat cable looms (but long enough to get the gear out for servicing) are truly a joy to behold--and doing them is a major skill.

Bob

 

When I first started putting racks together I always used to make such a mess of them, I found that as long as you diddnt need acess to the back of the rack the best way of doing it was to block the back of the rack off with blanking pannels and have a connector pannel at the bottom, with all of the different neccaserry connectors, this way no-one could see the looms behind the pannels and it looked extremly professional and extremley neat. Just a thought.

 

Rich

[mervaka]

I plan to do that as soon as I get my new effects rack. my currect rack only has front screws :/

[gnomatron]

I found that as long as you diddnt need acess to the back of the rack the best way of doing it was to block the back of the rack off...

 

It certainly looks nice, but you need to be careful with airflow if you're going to do that. It's also a pain making up the connector plate, surely? There's often connectors on the back of kit that you don't use 90%+ of the time. IEC cables have an annoying habit of falling out in transit, too!

 

Maybe making a door for the back of the rack is a better idea, and mounting a couple of fans in it - being careful they blow the right way of course! You could then have a non-door connector panel for the bottom 2 or 3U, and easy access to the back of the rack when you need it.

[Paul TC]

1U Cable management bars across the back of the rack as required give you somewhere to secure cables to and tidy up looms.

[palbin]

Thanks - havent tested the Behringer amps yet as the mid-speaker with four 15 inch elements it is intended to run is under its first steps of assembly.

 

However, I have "supercharged" a Behringer Eurolive 1520 speaker by means of replacing the 15 with a ditto JBL 2227 and the tweeter/horn with a ditto Jbl 2447/2352 (the latter somewhat cut for natural reaons as it is almost as big as the 1520), which required a lot of hand work,

reinforcements etc. but now is minutes from being finished and I find it a very appropriate test for my up-side-down Behringers to run one such boosted 1520 speaker - comparing it on the other side/channel with something more conventional - I will test it for 24 hour at 130 dB if I can just get at turning off my (only) neighbours hearing aid device, as she has very inconveni-

ently (for my intended test) turned up in her house for some spring work!

 

Best, palbin

[TallMike]

PCBs usually reside at the bottom of a unit.

QSC wouldn't agree with you on that

 

Nor would Camco.

 

An amp shoud work any way up, end of story! The output devices are mounted to a massive heatsink with air blowing through it.. it shouldn't have the chance to get hotter on one side than the other.

 

In fact, if you mount the PCB upside down, you won't get a layer of dust settling on the pcb... causing... guess what... heat build up and lack of proper airflow to the components!

 

With a switch-mode power supply, component weight is definitely not an issue - and a 'conventional' power supply is mounted to amp chassis with a large bolt, not onto the PCB. If the manufacturer can't build a chassis strong enough to not bend under the weight of its' own components, it shouldn't leave the factory! Amps sit upside down in flightcases all the time when they're in the van...

 

Mounting PCBs upside down is a far better idea IMHO, it just takes advantage of gravity.

 

- Mike