BillFitzmaurice.info

Hi,

I'm planning on building 4 titans 48.
Is there any difference on using the 3015lfa or the Lab 15?
I'm now thinking how to power them, I was thinking for a Crest cc 2800.

RMS-power (4 Ohm): 2x 965 Watt
RMS-power (8 Ohm): 2x 595 Watt

Will this be enough for 4x t48? 2 per channel.
How many watts do I need for 2 Titan's a channel?

Thanks!

Why not a QSC GX7? Better power than the Crest, almost a third the weight (15 lb for the GX7, 40 lb for the Crest), and the GX7 costs a few hundred less.

An amp capable of 60V @ 4 Ohms (900 watts @ 4 Ohms) is enough. All of the sub designs MUST be hard limited to 60VAC.

The lab 15 and the 3015lf have the same output.
It comes back to price.
While the lab 12 is often cheaper than the 3012lf for a T39, it doesn't usually work out that way for the lab 15 and 3015lf for the T48. The lab 15 is often more expensive.

The lab 15 and the 3015lf loaded T48's are limited to 60V, which = 450W 8 ohms.

RMS-power (4 Ohm): 2x 965 Watt
RMS-power (8 Ohm): 2x 595 Watt

You can see that the amp specs you mention for the Crest are more than adequate for 1 cab per channel, but getting a bit close to the bleeding edge of the amp capability for 2 cabs a channel.
60V into 4 ohms is 900W, with the 2 cabs per channel wired in parallel.
While it will probably run 2 cabs per channel, you might find it's getting into clipping before it hits max output for the T48's...

Okay, I'll go for the 3015LFA then.

For the amp, would the GX7 be better than the crest in performance, sound quality and price?
I'm using a Driverack PA2 as processor.

I've also got 4 J15's, would a QSC GX5 be enough voor 2 jack's per channel?
I've loaded them with the Eminence 3015.

Thanks!

Middelkevin wrote: I've also got 4 J15's, would a QSC GX5 be enough voor 2 jack's per channel?

Thanks!

Dutchman?

The Crest GX7 will allow the subs to run near maximum, but so will the amp. If the amp is run to it's max consistently, it's life will be shortened.

The GX5 should be enough since it's for the tops. Most likely, it will be plenty loud enought before you hit max on the amp.

Tom Smit wrote:

Middelkevin wrote: I've also got 4 J15's, would a QSC GX5 be enough voor 2 jack's per channel?

Thanks!

Dutchman?

Oh, I see! yes, Dutchman!
Thanks for your help.

Tom Smit wrote:The QSC GX7 will allow the subs to run near maximum, but so will the amp. If the amp is run to it's max consistently, it's life will be shortened.

The GX5 should be enough since it's for the tops. Most likely, it will be plenty loud enough before you hit max on the amp.

Fixed that for you, Tom!

Either amp will work well, but the GX7 will spare your back, and your wallet. The GX3 & 5 are not lightweight amps, so choose carefully. FTR, if you are pushing your system past half power, you need to double the cabinet count of the system. For each doubling of the power output, you gain approximately 3dB. For every doubling of the cabs, you gain approximately 6dB. I urge you to study Bill's Subwoofer placement thread, and try to follow the placement instructions outlined in it, whenever you can. That thread is based purely on the science of sound physics.

For the "tops", pretty much any amp that will do 500 watts @ 4 Ohms is more than enough. This will make the Jacks domme luide! Pick a pair of amps from the same manufacturer, as some amps vent cooling front to rear and others vent rear to front. This will prevent 1 amp from drawing in the hot exhaust from the other amp.

Since you are in Europe, there is (was) a thread about SYNC amps that are available to you.

Fixed that for you, Tom!

Oops.
Thanks.

DJPhatman wrote:

Tom Smit wrote:The QSC GX7 will allow the subs to run near maximum, but so will the amp. If the amp is run to it's max consistently, it's life will be shortened.

The GX5 should be enough since it's for the tops. Most likely, it will be plenty loud enough before you hit max on the amp.

Fixed that for you, Tom!

Either amp will work well, but the GX7 will spare your back, and your wallet. The GX3 & 5 are not lightweight amps, so choose carefully. FTR, if you are pushing your system past half power, you need to double the cabinet count of the system. For each doubling of the power output, you gain approximately 3dB. For every doubling of the cabs, you gain approximately 6dB. I urge you to study Bill's Subwoofer placement thread, and try to follow the placement instructions outlined in it, whenever you can. That thread is based purely on the science of sound physics.

For the "tops", pretty much any amp that will do 500 watts @ 4 Ohms is more than enough. This will make the Jacks domme luide! Pick a pair of amps from the same manufacturer, as some amps vent cooling front to rear and others vent rear to front. This will prevent 1 amp from drawing in the hot exhaust from the other amp.

Since you are in Europe, there is (was) a thread about SYNC amps that are available to you.

The Synq amps are indeed available here.
But I prefer the non-digital amps.
yesterday I was working freelance and the company I was working for was using Yamaha's.
They told me they liked those amps very much and I thought they sounded very well!
So I'm planning to order one, a Yamaha P7000S.
Or are there people who use the synq 2K2 for subs who like it?