What's to chat about?

[Bruce Weldy]

I'm not altogether convinced a Crown XLS1500 would outrun a Behringer NU/NX3000D. I think it would be a pretty close match.

Bruce, how many volts are you getting from your XLS1500's per channel & bridged? I was getting over 100v when I bridged the NU4-6000 channels with a 60hz sinewave.

I think the stated wattage is 1500 running bridged at 4 ohms. I haven't ever put a volt meter on 'em other than when I set the limiter. But, I've never had 'em get anywhere close to clipping. Calculated voltage is about 77.

In your example, the NU4 - 6000 is advertised at 3000 watts bridged and you got 2500 watts bridged....and I don't know if you took it into the red to get over 100 volts.

Bottom line, I just don't trust their ratings. I use one of the 4 channel amps for monitors. I think the stated power at 8 ohms was 350 watts (or something like that). I put the meter on it and could only get about 175 or so before clipping. I could only get it to the stated voltage by running it into hard clip. But, that's all I needed for monitors and it's served it's purpose.....got me 4 channels of monitors in a 2U chassis and that's what I needed.

I wouldn't consider putting one on my subs....unless it had at least double the wattage I need....

But, a lot of folks do use 'em. I just know they fudge their numbers.

[Bryan Cox]

In the end, if the NX3000D doesn't get me where I wanna be then I'll I'll invest in Crown or Crest amps again. But for now, the Behringer will do. Hell, I'm just gonna test the system a few times and then it'll go in storage for the better part of two years anyway.

[Seth]

Behringer has absolutely put an unrealistic number on their amplifiers and I don't trust their ratings either.

I still think the NX3000D will serve sub duty well enough and that "upgrading" to any other brand may not offer enough real and measurable performance gain to justify the cost.

I'll be curious to hear what voltage it actually measures and the impression of sound quality and volume.

[Bruce Weldy]

In the end, if the NX3000D doesn't get me where I wanna be then I'll I'll invest in Crown or Crest amps again. But for now, the Behringer will do. Hell, I'm just gonna test the system a few times and then it'll go in storage for the better part of two years anyway.

Just remember to stay with amps that have the same airflow in your rack. Crown runs front to back. Almost everyone else is back to front (which makes no sense to me....why pull dusty air from behind the rack into the amp?).

When I added the Behringer amp to my rack of Crowns, I opened it up and reversed the fans.

[AntonZ]

I'm seeing guys on YouTube make their own home brew goo, simply by melting trim scraps into a bit of Acetone, creating various viscosities from thick to thin.

Worked for me. Some cutoffs in a jar with acetone, overnight they dissolve, next day you can build your arrays.

Close the jar very well, or the acetone will be gone before anything has dissolved.
Don't let the goo sit in a jar for weeks on end. The acetone evaporates, even with the lid firmly on.

[Bryan Cox]

Behringer has absolutely put an unrealistic number on their amplifiers and I don't trust their ratings either.

I still think the NX3000D will serve sub duty well enough and that "upgrading" to any other brand may not offer enough real and measurable performance gain to justify the cost.

I'll be curious to hear what voltage it actually measures and the impression of sound quality and volume.

I'll keep you in the loop when I do the test. I'm on hold at the moment since the 3012LFs are on back order. I bought them from Full Compass since they offered free shipping and now they're on back order with no estimated ship date. Should've just went with good ole Parts Express.

[Bryan Cox]

In the end, if the NX3000D doesn't get me where I wanna be then I'll I'll invest in Crown or Crest amps again. But for now, the Behringer will do. Hell, I'm just gonna test the system a few times and then it'll go in storage for the better part of two years anyway.

Just remember to stay with amps that have the same airflow in your rack. Crown runs front to back. Almost everyone else is back to front (which makes no sense to me....why pull dusty air from behind the rack into the amp?).

When I added the Behringer amp to my rack of Crowns, I opened it up and reversed the fans.

Bruce,

I never knew that. Never paid attention I guess. Would that have much of an effect if my rack is open in the front and back when it's in use?

[Seth]

I'll keep you in the loop when I do the test. I'm on hold at the moment since the 3012LFs are on back order. I bought them from Full Compass since they offered free shipping and now they're on back order with no estimated ship date. Should've just went with good ole Parts Express.

4 in stock on amazon. Free one day shipping to my location
https://smile.amazon.com/Eminence-Kappa ... B001U1PK94

[Bryan Cox]

I'll keep you in the loop when I do the test. I'm on hold at the moment since the 3012LFs are on back order. I bought them from Full Compass since they offered free shipping and now they're on back order with no estimated ship date. Should've just went with good ole Parts Express.

4 in stock on amazon. Free one day shipping to my location
https://smile.amazon.com/Eminence-Kappa ... B001U1PK94

Yeah I saw that as well. I'm gonna go that route if the wait is too long. Thanks, Seth.

[Bryan Cox]

Seth, I pulled the trigger on Amazon. I got antsy after I saw your post. On another note, would the XTI2002 be enough amp for the T39s. They're supposed to be 800 watts @ 4 ohm's and I only need 625 watts to achieve the recommended 50 volts. I could get those used for the same price as the Behringer new.

[Seth]

I'd get antsy too. Three fresh cabs, all ready to go if they just had some drivers in them. I wouldn't have given it a second thought. I'm patient, but not that patient. Next day delivery starring me in the face, picturing tuning them up tomorrow, friends over for a trial jam sesh Sunday. I'm surprised you were able to hold out a whole 4 hours. That's Jedi level shit right there. LOL

I'm pretty sure the 3012LF's in a T39 call for a 55v limit. That's what my set of plans say anyway.

If Crown rates their amps at RMS, yes the XTI2002 should work fine, at 4 ohms it's rated exactly what the 3012LF is. Although, IMO it's not likely to create a noticeable difference in output from what you have. Operated at 8 ohms x2, it will have slightly more "headroom". I put that in parentheses because in a voltage limited system the amp will (well... should) never exceed the voltage it's limited at. So, it's not headroom in the traditional textbook sense. It will just never operate at the bleeding edge of it's capability which many believe contributes to a more reliable system. Could be true. Could not be. I personally don't know enough about electrical components to say. Makes sense though.

[Seth]

Just breezed through the XTI 2002 manual, https://3e7777c294b9bcaa5486-bc95634e60 ... iginal.pdf
They call their power ratings "Minimum Guaranteed Power", which sounds potentially intentionally misleading.
It's nowhere near as conclusive of a statement as "Minimum Guaranteed RMS Power, all channels driven"

The manual for one of my Ashly amps states it this way:

Ashly NE1600PE -
The two-channel power amplifier shall deliver a minimum power of 450 Watts RMS per channel into 8 Ohms loads and 800 Watts RMS per channel into 4 Ohms loads with both channels operating.
When switched into bridged-mono mode, the amplifier shall deliver at least 1600 Watts RMS into an 8 Ohms load.

I'm guessing there's a reason Crown isn't using the term "RMS".

[Seth]

Comparing the effect of two different amplifiers on peak volume:
One amp, let's just call this "The $400 amp", is capable of running the T39's at 50v/312.5 watts each, 1250 watts total power for all four.
And another amplifier capable of running the T39's at 56.6v/400 watts each,1600 watts total power for all four. Let's call this one "The $700 amp"

"The $700 Amp" will provide a maximum volume output advantage over "The $400 Amp" in the order of...



Wait for it



Drum roll please



1.07dB

[NukePooch]

Just remember to stay with amps that have the same airflow in your rack. Crown runs front to back. Almost everyone else is back to front (which makes no sense to me....why pull dusty air from behind the rack into the amp?).

When I added the Behringer amp to my rack of Crowns, I opened it up and reversed the fans.

Just to throw in a ringer, QSC's GX3 and GX5 have oddball side-to-side airflow.
Always thought it was weird to lump these in with the GX7 which has back-to-front airflow.

[Bruce Weldy]

Just remember to stay with amps that have the same airflow in your rack. Crown runs front to back. Almost everyone else is back to front (which makes no sense to me....why pull dusty air from behind the rack into the amp?).

When I added the Behringer amp to my rack of Crowns, I opened it up and reversed the fans.

Just to throw in a ringer, QSC's GX3 and GX5 have oddball side-to-side airflow.
Always thought it was weird to lump these in with the GX7 which has back-to-front airflow.

yeah, the GX7 is a totally different amp from the other two. Guess they wanted to fill out the GX line and used a different amp design to do it.