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Author Topic: Crown Ma12000i suffers on mid-hi duty!?  (Read 10161 times)

Kashif Hudson

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Crown Ma12000i suffers on mid-hi duty!?
« on: July 01, 2014, 11:12:38 AM »

We currently have a number of Ma12000i. They behave poorly with mid to high frequency duty. The clarity and precision just falls apart. We even A/B'ed the Crowns against Mackie m1400 in stereo and even with less power, the Mackies outperformed the crowns by a wide margin. Does anyone know if this is also the case with the 9000i & 5000i? Do they also suffer the same on mid-hi duty? Please help before we make a regrettable purchase to power our Community RS880's

Thank to all,

Hudson
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Tim McCulloch

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #1 on: July 01, 2014, 11:22:41 AM »

What is "suffer" as it applies to an amplifier?
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Kashif Hudson

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #2 on: July 01, 2014, 11:49:26 AM »

Please forgive my usage of suffer In regards to an amplifier if it is incorrect. Is it possible that the 12000i may be struggling or lacking in its ability to accurately reproduce mid or high frequency signals and is this phenomenon also present in the 9000i & 5000i. 2 of our 12000i were bought brand new and the other two purchased from another psw member. They all exhibit the same harsh high frequency behavior. There must be someone that understands amplifiers that can better explain what is happening so my question does not get ridiculed or lost in translation.
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Ray Aberle

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #3 on: July 01, 2014, 12:01:45 PM »

Please forgive my usage of suffer In regards to an amplifier if it is incorrect. Is it possible that the 12000i may be struggling or lacking in its ability to accurately reproduce mid or high frequency signals and is this phenomenon also present in the 9000i & 5000i. 2 of our 12000i were bought brand new and the other two purchased from another psw member. They all exhibit the same harsh high frequency behavior. There must be someone that understands amplifiers that can better explain what is happening so my question does not get ridiculed or lost in translation.

Kashif, can you give a bit more details as to what else is in your system?

I have a 9000i that I use for STX815M wedges, and it sounds great across all frequencies. (Purchased brand new when they were first released in 2008.) So, perhaps there is something in your system that is hampering the ability of your 12K - and if we know what else you're working with maybe something will jump out at us.

-Ray
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Kashif Hudson

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #4 on: July 01, 2014, 12:18:29 PM »

Thank you for attempting to help Ray. There are only two pieces of equipment before the crowns. A pioneer Djm-5000 mixer and a Lake Lm-44. The crowns are plugged  into a motion labs distro 30a 240v. With the same exact setup and settings the mackie m1400 sounds much like Mr. Langston Holland describes the sound of the Camco vortex 6 for mid-hi's. I remember seeing a discussion on psw a while back about a similar issue brought to light about the crown 12000i in particular, but have been unable to locate it after much searching.
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Kashif Hudson

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #5 on: July 01, 2014, 01:34:04 PM »

Below is a quote from John Roberts in regard to a discussion started by Langston Holland about the I tech 8000 mid-hi behavior. If anyone is interested in reading further please use the search function and type "I tech 8000 mid-hi issue". I suspect the Ma12000i may be suffering a similar ailment. It looks like the 9k & 5k will perform better much like the I tech 6k & 4k did for mid-hi!

******If the loss is in the output filter as it appears, I'd expect the loss to be both gain and power. Applying corrective EQ boost would cause the amplifier to clip before raising the final output to full power.

This mechanism is pretty much limited to the very highest frequencies which in a natural distribution of musical energy will   be lower level providing the headroom needed to allow such a correction to work, that said it is far from ideal and this amp would need to be de-rated for use in the HF section of a multi-amped system.

Note: For some electronic music sources and close miked applications the natural distribution of musical energy may not be as reliably shaped as simple acoustic music so YMMV.*****
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Jim McKeveny

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #6 on: July 01, 2014, 06:12:38 PM »

Community RS880s have a passive network and limiting built-in. Power handling is only rated at 400w.  I would look for issues here rather than on fresh amps...
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David Sturzenbecher

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #7 on: July 01, 2014, 06:47:06 PM »

Below is a quote from John Roberts in regard to a discussion started by Langston Holland about the I tech 8000 mid-hi behavior. If anyone is interested in reading further please use the search function and type "I tech 8000 mid-hi issue". I suspect the Ma12000i may be suffering a similar ailment. It looks like the 9k & 5k will perform better much like the I tech 6k & 4k did for mid-hi!

******If the loss is in the output filter as it appears, I'd expect the loss to be both gain and power. Applying corrective EQ boost would cause the amplifier to clip before raising the final output to full power.

This mechanism is pretty much limited to the very highest frequencies which in a natural distribution of musical energy will   be lower level providing the headroom needed to allow such a correction to work, that said it is far from ideal and this amp would need to be de-rated for use in the HF section of a multi-amped system.

Note: For some electronic music sources and close miked applications the natural distribution of musical energy may not be as reliably shaped as simple acoustic music so YMMV.*****

I use Crown iTechHD 12000's (same amplifier section as the Macrotech 12000i) on the HF section of JBL Vertec quite often.  I have never heard, nor had any of the numerous A list engineers comment on any HF irregularities.
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Kashif Hudson

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #8 on: July 01, 2014, 09:07:22 PM »

David,

Here is a link to the amp review done by Langston Holland http://forums.prosoundweb.com/index.php?topic=132359.0
I think you will find this interesting especially if you had I techs previously. Langston also noticed that the sound greatly improved with HD models so no quarrels there.
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Kashif Hudson

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #9 on: July 01, 2014, 09:55:27 PM »

Jim,

Thanks for taking the time to contribute. 57v rms and 126v peak are easily converted and entered into the Crown and the Lake Lm. The 880s sound great at low levels and at higher levels. Infact, most would agree that the 12000i with the extra voltage capabilities should be superb at handling one 880 per side with plenty to spare. The problem is that in the higher frequencies the 12000i does not perform as well as it does in the lower bands. I noticed the problem that Langston did with the Itech 8k. John Roberts gave the technical explanation and theory for what is happening. Langston also made crown aware of the issue a long time ago. Please look at this discussion to help you understand further . These men are much more knowledgeable than I am. http://forums.prosoundweb.com/index.php?topic=81939.0
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Jim McKeveny

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #10 on: July 02, 2014, 08:11:37 AM »

Read thread. Quite an issue. Best of luck!
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Kashif Hudson

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #11 on: July 02, 2014, 12:22:41 PM »

Thanks Jim. Just an update. Today we used a 9000i and 5000i on the RS880s and the sound quality in high frequency range is better than with the 12000i. In theory we all know an amplifier should amplify the signal we put in it. But I'm starting to agree with the likes of Ivan Beaver, Art Welter and a few others that encourage side by side comparisons to really experience the sonic character of the equipment we use. Spec sheets alone is only half the story and some things are not evident with measuring. All in all, we should pay attention to what we hear and ask questions even if our peers don't notice. Sometimes, they simple have not done a side by side comparison to see if they are able to notice a difference.
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Jim McKeveny

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #12 on: July 02, 2014, 01:17:22 PM »

Seems Crown made an engineering and marketing decision that has unexpected sonic consequences for some users. This is too bad. Pro users are typically discriminating, loyal, purchase dozens of units, and influence the purchase of many more.

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Matthew Knischewsky

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #13 on: July 02, 2014, 10:28:34 PM »

Thanks Jim. Just an update. Today we used a 9000i and 5000i on the RS880s and the sound quality in high frequency range is better than with the 12000i. In theory we all know an amplifier should amplify the signal we put in it. But I'm starting to agree with the likes of Ivan Beaver, Art Welter and a few others that encourage side by side comparisons to really experience the sonic character of the equipment we use. Spec sheets alone is only half the story and some things are not evident with measuring. All in all, we should pay attention to what we hear and ask questions even if our peers don't notice. Sometimes, they simple have not done a side by side comparison to see if they are able to notice a difference.

Do you have any measurements of the various amplifiers powering your speaker?
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David Sturzenbecher

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #14 on: July 02, 2014, 10:40:15 PM »


Seems Crown made an engineering and marketing decision that has unexpected sonic consequences for some users. This is too bad. Pro users are typically discriminating, loyal, purchase dozens of units, and influence the purchase of many more.

Have you seen "no crown" on any riders?


Sent from my iPhone using Tapatalk
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Kashif Hudson

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #15 on: July 02, 2014, 11:30:37 PM »

Matthew,

No raw data has been collected from the amplifiers as yet. We sort of tried the 12000i on mid-hi duty and noticed the behavior by ear. But we are confident in using the 9000i and 5000i for the job.

Let me be clear to all; We are happy with our current crown setup because it works for us! I would also recommend these units to anyone.

However, I now understand from the discussions that I linked in previous posts why we heard a sonic difference between the amplifiers. Crown already explained a few points on the subject and we are satisfied.

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Ivan Beaver

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #16 on: July 03, 2014, 07:45:10 AM »

Do you have any measurements of the various amplifiers powering your speaker?
There are TONS of different measurements that can be done on all sorts of gear. 

The "simple" numbers do little to tell about about the actual sonic character of an amp-speaker-mic etc.

I love the people (especially HI-FI guys who say they can hear differences but you can't measure them.

WRONG- they are just using the wrong tools measuring the wrong thing.

We can measure all sorts of things that we cannot hear/detect.

BUT you have to be measuring the right thing.

And when comparing products-if you don't have the same measurement-collected in the same way-you really don't have anything to compare to.

Hence my insistence about side by side listening.

AND EVEN THEN- it is often hard to actually setup a fair comparison.

Have you ever tried to compare full range cabinets side by side?

How do you set the levels so they are equal?  Anybody who has tried (and has a basic knowledge level) will quickly realize it is much harder than expected.


Do you use pink noise?  What if one cabinet has a response that is not as flat as the others?  What if one goes lower or higher?  Do you use a sine wave at 1K?  What if one cabinet has a little peak at 1K while the other has a little dip?

Do you try to use something like Smaart-TEF-Systune etc?

THEN it gets even harder to figure out what is "equal".

It is amazing how different one cabinet can sound-even when the level is 0.5dB louder.  You "think" you hear all sorts of differences.

I know I have been fooled by even small levels.

I'll stop now--------------

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Jim McKeveny

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #17 on: July 03, 2014, 10:37:13 AM »

Have you seen "no crown" on any riders?


Not to date. But I have seen "No Vertec". "No EAW". "No Meyer M2D" etc. Perhaps not completely rational, but surprising stuff nonetheless.

It is obvious that first-tier artists & management wholly prefer the packaged FOH systems of speakers/amps/processing from a single manufacturer a la L'Acoustics, D&B, etc. Big upfront buy-in costs. ? returns.

The days of system component mix & match (and the sometime discovery of particular combination response aberrations) are fairly well done for national soundco's. Regionals who grew used to the incrementalism ( i.e.: speakers this season, amps next, processing later) of rig improvement may have to reconsider that methodology.
« Last Edit: July 03, 2014, 11:04:17 AM by Jim McKeveny »
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Chris Grimshaw

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #18 on: July 11, 2018, 03:34:33 AM »

Hi all,

Sorry to bump an old thread.

I was just wondering what the conclusion was, regarding using the larger Crown Class I amplifiers for mid-high duties.
I have an MA12000i here that I'd like to use for some full-range speakers (once I've built the crossover). The linked thread looked like the iTech has a load-dependent HF response. Since this amp will only see use on one set of speakers, I think I'm okay just to EQ that out. Is that correct?

Thanks,
Chris
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Tim McCulloch

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #19 on: July 11, 2018, 11:43:24 AM »

Hi all,

Sorry to bump an old thread.

I was just wondering what the conclusion was, regarding using the larger Crown Class I amplifiers for mid-high duties.
I have an MA12000i here that I'd like to use for some full-range speakers (once I've built the crossover). The linked thread looked like the iTech has a load-dependent HF response. Since this amp will only see use on one set of speakers, I think I'm okay just to EQ that out. Is that correct?

Thanks,
Chris

Measure the rig in situ with Smaart or Systune or whatever you use.  Correct as you feel necessary.

In 11 years of using both original ITechs and the newer HDs I've *never* had a BE or PM say "hey, those amps don't sound right".  I think that's because the BE voices the rig to his/her preferences so any minor changes in response at the top end of a pass band simply doesn't get noticed.
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Chris Grimshaw

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #20 on: July 11, 2018, 12:52:44 PM »

Thanks, Tim.

It was mentioned in the thread linked a couple of pages back that the HF quality suffers, though I do wonder if it was just down to the frequency response changes. It looks like the images have all disappeared now, but I've seen what happens when you change the HF impedance with a switching amplifier.

Time for a shootout between the MA12000i and the iNukes I'm using at the minute. I expect the Crown to sound better, but if that's the case I'll have to find another sub amp.

Chris
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Steve Ferreira

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #21 on: July 11, 2018, 01:01:00 PM »

I have first gen ITech 8000s and have never noticed anything in the mid highs. I have also used Itech 5000s, 9000s and 4x3500 and never noticed anything out of the norm.
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Tim McCulloch

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #22 on: July 11, 2018, 01:47:56 PM »

Thanks, Tim.

It was mentioned in the thread linked a couple of pages back that the HF quality suffers, though I do wonder if it was just down to the frequency response changes. It looks like the images have all disappeared now, but I've seen what happens when you change the HF impedance with a switching amplifier.

Time for a shootout between the MA12000i and the iNukes I'm using at the minute. I expect the Crown to sound better, but if that's the case I'll have to find another sub amp.

Chris

I think it was Langston Holland who documented this and he's still around in Florida, somewhere.  He moderated the Measurement & Testing forum previously...

There was discussion about the likely nature of why Crown did what they did, IIRC.
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Kashif Hudson

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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #23 on: September 02, 2018, 06:48:50 PM »

Thanks, Tim.

It was mentioned in the thread linked a couple of pages back that the HF quality suffers, though I do wonder if it was just down to the frequency response changes. It looks like the images have all disappeared now, but I've seen what happens when you change the HF impedance with a switching amplifier.

Time for a shootout between the MA12000i and the iNukes I'm using at the minute. I expect the Crown to sound better, but if that's the case I'll have to find another sub amp.

Chris

Hi all,

Sorry to bump an old thread.

I was just wondering what the conclusion was, regarding using the larger Crown Class I amplifiers for mid-high duties.
I have an MA12000i here that I'd like to use for some full-range speakers (once I've built the crossover). The linked thread looked like the iTech has a load-dependent HF response. Since this amp will only see use on one set of speakers, I think I'm okay just to EQ that out. Is that correct?

Thanks,
Chris


Hi Chris,

After doing away with the 9000i & 5000i in our inventory, we standardized with the 12000i across the board.  Though we use the 12000i for sub duty 99% of the time, they are fully capable of substituting for our I-Tech 4x3500 on full-range or mid-high applications if needed.  As Tim said, if the system is voiced to ones preference then things should be ok.

The phrasing I originally used to describe the first impressions of what we heard that day was not very technical and was not meant to scare anyone away.  The amps are solid and have served us well. 
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Re: Crown Ma12000i suffers on mid-hi duty!?
« Reply #23 on: September 02, 2018, 06:48:50 PM »


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