BillFitzmaurice.info

Hello members happy Thanksgiving , thanks for awesome BFM design, help and knowledge members here .
I 'am about to put together a live sound speakers which contain 6 Dr250 , 6 T48 ( 2 with lab 15 ,4 with Kappalite 3012 LF ) so i'm looking for an optimal amp to power them with some head room ? currently I have Xti 4000 & gx5 , all will run with driver rack PA+
A . could the XTI handle 3-4 Titans per side ? parallel
B . there are any issues with mixing Lab with 3012LF ?
C . Could the Pevey Ipr 3000 have enough power for 3 DR per channel ?
Thanks in advance

Any particular reason to mix drivers in the T48's?

In another thread Bill says to run lab15's (in the other thread it was 3015lf, but same difference) on a different amp channel to 3012lf's due to differing sensitivity.
Since the limit for the lab15 is 60V and the 3012lf's is 50V that has to be also added in.

XTI4000
It will run 2 x 3012lf loaded T48's hooked in parallel on each channel.
It will run 4 x 3012lf loaded cabs on one channel (but that is stretching to the bleeding edge), but falls short on the required 60V to run the lab loaded cabs on the other channel.

The IPR2 3000 will be about twice as much as you need for 6 x DR250's

The GX5 would run 2 x 3012lf loaded T48's/channel, but isn't up to 3 x DR250's/channel or the lab15 loaded T48's

It's not a total lightweight, but well priced. The Crown XLI 1500 would have the required voltage for the lab15 loaded T48's...

I find 3x 3015lf loaded t48 to be the leeding edge for an xti 4002. thermal issues rear their head at this point even with 50 volt limit and no clip.

Edit

3 per side

the reason to mix drivers in the T48' couple years back right before the neo went up I bough 4 3012lf .

mino00 wrote:the reason to mix drivers in the T48' couple years back right before the neo went up I bough 4 3012lf .

Then, buy two more and they all match.

Hello
couple years back I build 2 T48 with the lab 15 now I want to add 4 more to the herd which I have 4 3012L available so which is my best option ? Before I make my saw dust
Get rid of 3012Lf go all for lab 15 or 3015lf or build which I have and limit all at 50 v ?
Thanks

if the 3012lf are new in box, you should be able to sell them and buy 3015lf at only a 50 to 75 loss (if that). dont even consider the lab 15, its mad expensive.

For optimal performance, ease of tuning and to avoid impedance/overheating issues, all cabs on the same channel of the same amp should have identical drivers. While you can "make it work" with different drivers, it's never going to be as perfectly setup/tuned as it could be with identical drivers. That's just physics, no way around it.

This is just my humble opinion, but I don't see the merit/logic of running amps below their rated impedance. If an amp is rated to run at 4 ohms per channel, running it at 3.5 or even 3 ohms is just asking for trouble. If you have that many cabs, buy another amp. Any decent quality amp (Crown, QSC, Peavey, etc) will run all day long at their rated impedance loads. If you absolutely need to run at 3 or 2.5 ohms per channel, buy a 2-ohm per channel capable amp. My two cents.

A crown xti 4002 (2 ohm rated amp) with 3 cabs per channel can be thermalled in about 44 seconds

I've seen a single 32 bar phrase of a track take it from 37 C to 75 C in that time frame. meter in system architect not exceeding neg 3 db.

believe it was this track

That video was one of the more disturbing things I've seen in awhile. Pretty original, though, so points for that. That track is basically pure sine waves...like most dubstep-type-stuff these days.
The XTI4002 is a very good amp, but not a great amp. That would be why the QSC PLX3602 is $400 more. Of course there's always the assortment of variables like line voltage and ambient temperature, etc. FWIW, I don't recommend running ANY amp at 2 ohms stereo at full tilt for any length of time. But, an amp rated to two ohm stereo should do 4 ohm stereo at full tilt, all day long in the middle of summer, no problem.

Truth. for anyone whos interested theres a guynselling a pile of plx 3602 @ 900 a piece over on prosoundweb. driverack 260 for 499 as well i believe.

Im still trying to save for a damn itech 5000hd (used).

Maybe after NYE

Sorry about the vid.... Honestly didnt even watch it. got the track on vinyl

I'm assuming that's $900 for a used 3602...not a bad deal, but not fantastic, depending on the condition/age/history of the amp. I bought a used 3602 for $600. The seller was not forthcoming about any details, though he had great feedback on the Talkbass forums.

Turned out that most of the plastic spacers (like motherboard standoffs) that hold the PCB were broke, so the PCB vibrated like crazy. The weird thing is that the case of the amp had zero damage, save for some rack rash. Anyway, I glued in some heavy rubber feet to act as "feet" for the PCB and it was/is solid...like new again. That was 4 years ago...thing's been going strong since.

Hello
How about these amp used QSC RMX 4050 or brand new Peavey IPR2 5000 for a same price .
Thanks

mino00 wrote:Hello
How about these amp used QSC RMX 4050 or brand new Peavey IPR2 5000 for a same price .
Thanks

mino00, it's not the amp, it is that you are trying to put too many cabs on one channel. The RMX4050 should handle 3 subs per side with no issues, but I will never recommend more than 2 DR250 per channel. You are in for longer amp life by buying 2 smaller amps, like the Peavey IPR3000, the QSC PLX2502 or the Crown Drivecore XLS2000. If the RMX4050 is a really good deal, and you don't mind the weight, use it for subs, then snag a pair of the IPR1600 or the XLS1500 for the DR250s. Amp choices are plentiful, but strive to go no lower than 4 Ohm nominal loads on each channel. The T48 are 10 Ohm, so 3 on a channel will be 3.33 Ohm. The RMX4050 is super heavy at 68 lb (30.84 kg).

Just in case you missed it:

In another thread Bill says to run lab15's (in the other thread it was 3015lf, but same difference) on a different amp channel to 3012lf's due to differing sensitivity.

So please, take everyones advice, run 1 amp with 2 x 3012lf loaded cabs per channel.
Another amp with the lab 15's one per channel...