Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Jeff Schoonover1]

Are you doing EDM with *sustained* full power output requirements?

I am a bass player, the rig will be used onstage for large shows where I'm often competing with hard-hitting drummers and two marshall stacks from guys who haven't figured out that loud stage volume = bad sound, and sound men who take all bass out of the mix, except hugely overbearing and non-linear kick-drum boom.

As for the power output spec at 1kHz, that's because it's an easy mark to hit.  In general terms the power supply can only recharge at a rate equal to or lower than the AC line frequency, so the lower the reproduced frequency at greater magnitude, the lower the output will be.

This is the most excellent and concise definition of how these new PWM amps are different than old-school transformer based amps.  I kinda knew this, but couldn't have defined it so precisely.

That all said, find an amp that puts out even 2000w/ch and power up your subs... and let it run for a couple of minutes or until the speakers catch fire.

This was my summation at first as well.  I was going to put it on my XTi 4000 at their advertised 3,200W and see how it sounds, and go from there.  But, having spoken with a couple of my bosses who own Clair Bros. rigs, they're pretty sold on the idea of having at least 2-3 times the continuous power rating.  Based on the clarity depth and volume of the low end produced, I know they're on to something.

The fact is that your subs will NOT dissipate 3000 Watts of heat, nor will they mechanically survive that power at subwoofer frequencies for very long.

I might be inclined to agree, but I have the box loaded with twin Eighteen Sound TLW3000.  AES power is 1,800W, and Program Power is 3,600 with peak bursts to 10KW.

...you are tilting at windmills, Mr. Quixote.

Nice

Keep in mind the 6000watts at 1K Crown claims is in 4ohm bridged mode

This box will be wired for 4 Ohms.

[Jeff Schoonover1]

Screw the numbers you're reading.  The subs go loud with a 6002 bridged into each!

LOUD is do-able now with my XTi 400 and a couple of 15" Eminence-loaded boxes.  What I'm after is loud, but only while maintaining linearity - I.E. low distortion and clean, detailed, accurate reproduction.  I want to hear the notes.  I don't just want loud, but with overhang and boominess, like I have now.

[Spenser Hamilton]

I am a bass player, the rig will be used onstage for large shows

There is a wide chasm between bass player on a loud stage and festival level EDM playback. I've played in loud death metal and hardcore bands next to Mesa half stacks and my little 200 watt Peavey tube amp feeding a Mesa 4x10 never ran out of gas.

What are you guys gonna do when you walk into a venue and backline power is limited to a single 15A circuit?

[Jeff Schoonover1]

I have a pair of xti6002 amps.  For a while one ran a pair of Srx725 tops, and I had a pair of itech amps running subs.   A few weeks ago I reconfigured the amp rack and since the. It's been an itech on tops, and each xti6002 bridges into a SRX728 sub.

Do you hear a difference?  I'm thinking if the 6002 can power one of those adequately, I may be able to do fine with a 6002. Where are you drawing power?  The wall, or do you have distro power? 
Would you by chance have compared the 6002 with the 4002?  Is it really twice the amp?

[Jeff Schoonover1]

There is a wide chasm between bass player on a loud stage and festival level EDM playback.

Agreed, but there are plenty of low, sustained notes produced by bass guitar at times.  While they aren't a perfect sine, like EDM, they're still pretty heavy with the fundamental frequencies.

I've played in loud death metal and hardcore bands next to Mesa half stacks and my little 200 watt Peavey tube amp feeding a Mesa 4x10 never ran out of gas.

I said it before, but I have a 2x15" + 2x10/horn rig powered by an XTi4000.  Loud is not the problem.  Fidelity and linear response - while being loud - is the goal. 

What are you guys gonna do when you walk into a venue and backline power is limited to a single 15A circuit?

I don't play in rooms like that, but if I did, I'm certain my greatly lowered volume would only require a small fraction of that.

[John Roberts {JR}]

It used to be that Crown set the gold standard across the board. One of their big selling points was that they guaranteed that an amp would put out a minimum of X watts, from 20-20KHz continuously.
 Fast forward to now, their top-end stuff is competitive, but others have bested even that.  In the DJ and small PA market, we have the XTi series.  I have an XTi 4000 for mids, and am pretty happy with it.  About 3KW, and DSP for a good price.  But - the specs aren't measured as they once were.

Anyhow, I'm thinking of an XTi 6002 for a dual 18" sub I just built.  The XTi specifies 6,000 watts - BUT ONLY AT 1 kHz!  What does this mean?  Is my amp only going to do 3,000 watts at 40 Hz where I need it?  Am I getting gypped and ought to shop for something else?

Has anyone measured or know the math on what these amps will 'really' do in a musical spectrum range?  What will an XTi 6002 put out continuously from 30 Hz to 100 Hz?

Nobody makes amps for continuous power, and they haven't for several decades because music is not continuous.

The specific question about why spec power at 1kHz is because you can print a slightly larger power number at frequencies well above reservoir cap ripple. In real terms (like dBW) the power difference is insignificant, but consumers making purchase decisions think 10 or 20 more watts is important.

JR 

[David Allred]

10% (typical difference between 1K vs 20-20K measurements) more or fewer watts is pretty insignificant in volume difference. 

[Jeff Schoonover1]

Ok, so it seems that my fears were unfounded.  A promised 6KW @ 1KHz from an XTi will be just about the same as from any other amp delivering 6KW with 20-20K measurement - Cool!
Another observation and question :
I am of the opinion that watts are watts.  Specifically, if an XTi is giving 6KW cleanly, within all of its normal operating parameters (no clipping, no thermal limiting, and (ideally) adequate power supply -no voltage sag) There will be no difference, audible or otherwise, between that and an i-Tech HD, or any other high dollar amp with the same output capability.  The difference in price comes from robust-ness, protection, heat dissipation, features like better DSP, etc.
Yay/Nay?

[David Allred]

within all of its normal operating parameters (no clipping, no thermal limiting, and (ideally) adequate power supply -no voltage sag) There will be no difference,

With this caveat, yay.

[Lance Hallmark]

Ok, so it seems that my fears were unfounded.  A promised 6KW @ 1KHz from an XTi will be just about the same as from any other amp delivering 6KW with 20-20K measurement - Cool!
Another observation and question :
I am of the opinion that watts are watts.  Specifically, if an XTi is giving 6KW cleanly, within all of its normal operating parameters (no clipping, no thermal limiting, and (ideally) adequate power supply -no voltage sag) There will be no difference, audible or otherwise, between that and an i-Tech HD, or any other high dollar amp with the same output capability.  The difference in price comes from robust-ness, protection, heat dissipation, features like better DSP, etc.
Yay/Nay?

Keep in mind though that most steady output for that sized amp will be in the hundreds of watts, not thousands. For this amp to generate 6000 watts I'm going to guess it would be pulling around 50 amps from the wall (@110v) to be able to do it:
1/3 Power Pink Noise Typical of program material at extreme clip @ 2ohms 35.2 amps 989 watts (110v)

[ProSoundWeb Community]