[sub_crazy]

I just picked up a used QSC PL 9.0 PFC and was wondering if there is a fan mod for this beast. I know it uses 4 fans and it is easily audible at the LP so I was hoping I could quite it up a bit.

I will be using it to drive a pair of LMS Ultra 18" each in there own 4 cuft enclosures.

Thanks in advance for any advice.

 

[bambino]

All i have is a comment. WoW! 4 fans that thing must be a beast!:yikes:

I guess in reality you could take it apart and see what it uses for fans then try to find something of the same size with a lower db rating. I have never done a mod like this so i would imagine you would need to stay in the same voltage and ma ratings but like i said i really know nothing about doing it. Somebody will have a great idea though.:T

 

[sub_crazy]

Beast is right but it only weighs 60 lbs:T

3200 watts X 2 into 4 ohms is an insane amount of power so I want to make sure I don't let it burn itself up with a fan mod.

If you hear of a small quake in S. California I swear it's not me

 

[bambino]

What are you gonna drive with that thing besides the roof off your house?:devil:
You won't even hear the fans running once you turn the volume up allthough 4 fans could sound like a little Dustbuster. Definatley sounds like an awesome amp.:T

 

[GranteedEV]

Open up the case and unscrew one of the fans.

The things to look at are

-voltage - usually 24 or 12
-size - IE 25 x 80 x 80
-name - we can google it to get a CFM air flow and noise (db) value which we can use as a bit of a reference to know what the amp wants and will be an improvement without hurting the amp

Post it here and we'll try and find a quiet effective fan to replace them with

 

[sub_crazy]

Thanks GranteedEV,

I will try that out sometime this week and post the results.

Thanks again.

 

[Ricci]

I'm not sure that I would mess with it, but if you do follow granteedEV's advice. Can't you place the amp in another room or a closet? You should have a 30amp line run for it too.

Welcome to the 9.0 club. It's fun. :bigsmile:

 

[sub_crazy]

I am not surprised you would be in the 9.0 club Ricci, in fact I wouldn't be surprised if your a 2 or 3 time member:clap:

If your suggestion is to not mess with it then that's all I need to know, I got a 500 foot spool of 10 gauge in the garage so longer speaker cable runs it is.

I was planning on running a 30 amp line for it but first I have to figure out where I can stash it.

I will be running 2 LMS 18" each in there own 4 cuft sealed enclosures so the 9.0 seamed like a perfect fit, what do you think?

I always appreciate your advice Ricci, your a sub guru:hail:

 

[Ricci]

Should be a great match up. By all means if you want to give a fan mod a shot go for it. I've had my 9.0's opened up multiple times. My line of thinking is just that with 4 large fans it is still going to be loud even with using quieter ones. If it is possible to stash it somewhere out of the way that'd be an easier solution.

 

[Wayne A. Pflughaupt]

Welcome to the 9.0 club. It's fun. :bigsmile:

So – have you ever even seen the -20 dB lights activate?

Regards,
Wayne

 

[sub_crazy]

If my electrician friend is free this weekend I am going to have him come over to see where we might place the 9.0 so that he can run the 30 amp line and speaker cables. I think it's going to be tricky but we'll see.

I am probably going to take the 9.0 to QSC to have a check up and ask if there is any fans mods they can perform if I have to have it in room. I am about 45 minutes from the QSC factory so I want them to give it a clean bill of health anyway.

I am with Wayne on finding out how hard you have pushed your 9.0's Ricci?

Thanks again for all the advice.

 

[Wayne A. Pflughaupt]

Just curious, what kind of plug is on the power cable?

Regards,
Wayne

 

[sub_crazy]

It's got a 30amp plug.

 

[Wayne A. Pflughaupt]

Like one of these?

Regards,
Wayne

 

[sub_crazy]

Yeah, it's like the top 2, I have it at home so not sure which though. It will play in a normal 20 amp circuit though if you change out the plug.

 

[Wayne A. Pflughaupt]

Well sure, it would even play in a 15 amp circuit, if you changed the plug. I doubt you would want to do that, though!

Regards
Wayne

 

[sub_crazy]

True, so true

 

[Lucky7!]

Just as an FYI, here are two fan roundup tests I found looking for info on other products. As lots of spec and test data is in one place with these, it might help making a decision.
http://www.xbitlabs.com/articles/coolers/display/120-140-fans-roundup.html
http://www.xbitlabs.com/articles/coolers/display/140mm-fan-roundup.html

I'm sure there are others out there in the 'puter mags/forums too, but I don't read them.

 

[sub_crazy]

Thanks for the link A9X.

I will definitely have to check through those links.

 

[Ricci]

So – have you ever even seen the -20 dB lights activate?

Regards,
Wayne

I've had the amps clip a few times running up near REF level with the bassiest action movies. That needs to be qualified with the fact that my subs are run flat all the way down to where the amps roll off <3hz and there is a good deal of boosting going on below 20hz to get the response below 12hz up flat with 60-100hz. That sucks some serious juice out of the wall, which is a 50A 240v circuit in my case. It's the heavily boosted sub harmonics that caused it every time. Also I normally listen at much lower -10 to -15db from REF levels. That only happens during testing where I'll decide to really push things. With music or stuff that doesn't have much below 20hz I can listen at a fairly solid listening level and the signal lights don't even show activity. :T