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Old 30th September 2012, 06:58 AM   #1091
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Originally Posted by djk View Post
" I have found some used Crest CA-9 and CA-12 amps for enticing prices"

How about $340 with free shipping, brand new.

Beach Audio has some that are 220V only at that price.
I don't see em: Beach Audio Crest Link

Hidden part of the site, maybe?

Wouldn't I need some sort of step down voltage transformer to make the 220V version work in the US?
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Old 30th September 2012, 07:31 AM   #1092
NEO Dan is offline NEO Dan  United States
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Originally Posted by CRESCENDO View Post
I don't see em: Beach Audio Crest Link

Hidden part of the site, maybe?

Wouldn't I need some sort of step down voltage transformer to make the 220V version work in the US?
No just a correctly wired outlet. These big amps you are looking at need/require a better service than the standard household outlet to make full power, especially at the duty cycle of your program material.
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Old 30th September 2012, 09:21 AM   #1093
djk is offline djk
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http://www.crestaudio.com/media/pdf/...ec_10-5-98.pdf

Crest Audio CPA900CG220V Crest Dj Amp 900w Into 4 Ohm | eBay
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Old 30th September 2012, 07:28 PM   #1094
NEO Dan is offline NEO Dan  United States
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http://www.crownaudio.com/media/pdf/amps/137435.pdf

http://www.crestaudio.com/assets/lit...6226_13000.pdf
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Old 30th September 2012, 09:26 PM   #1095
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No just a correctly wired outlet. These big amps you are looking at need/require a better service than the standard household outlet to make full power, especially at the duty cycle of your program material.
Finding 220 outlets is difficult on many smaller gigs.

"Big amps" like the CA9 or 12 run fine off 20 Amp 120V Ac circuits found in standard commercial or current household wiring.

I run two Crest CA 9 (one bridged mono at 4 ohms) and a QSC PL 3602 (stereo 2.3 ohm operation) off a single 20 amp 120 volt circuit.

I have run double that off a single 20 amp 120 volt circuit, didn't find out all the outlets were the same circuit for several days until a miswired guitar amp popped the breaker.

The amps have never popped a breaker except when a CA 9 PSU capacitor shorted to ground.

Art
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Old 30th September 2012, 09:33 PM   #1096
NEO Dan is offline NEO Dan  United States
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What are the top rails at in the CA9? I don't see this amp as a contender vs the PLX3402's as it's double the weight and no SMPS...
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Old 30th September 2012, 10:22 PM   #1097
Mark Kravchenko --- www.kravchenko-audio.com
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Quote:
The amps have never popped a breaker except when a CA 9 PSU capacitor shorted to ground.
Now that would have been a bit of fireworks.

Most circuit breakers are capable of passing ten times their rating for breif periods of time.

I think you prove that in spades Art.
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Old 30th September 2012, 10:25 PM   #1098
NEO Dan is offline NEO Dan  United States
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Looking more closely at the datasheet that CA9 is an amazing deal for the money, but I don't think I'd expect to get away with running multiples on anything but a beefy 220v service.
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Old 1st October 2012, 02:39 AM   #1099
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Quote:
Originally Posted by NEO Dan View Post
No just a correctly wired outlet. These big amps you are looking at need/require a better service than the standard household outlet to make full power, especially at the duty cycle of your program material.
Quote:
Originally Posted by weltersys View Post
Finding 220 outlets is difficult on many smaller gigs.

"Big amps" like the CA9 or 12 run fine off 20 Amp 120V Ac circuits found in standard commercial or current household wiring.
Yeah, I don't think we've ever had a gig with anything but 120V (15A or 20A) - with the exception of one gig last year off an MQ Power Whisperwatt generator.
So, I think I'd be more comfortable with 120V amps. I would, however, like to further educate myself on different power configurations (3 phase included) should the opportunity/conditions arise.
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Old 1st October 2012, 02:49 AM   #1100
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Originally Posted by CRESCENDO View Post
Before I click "Start Measuring" I clicked "Check Levels" to be sure everything was still even - yet, it popped up with "Level is Low" before audio was heard through the sub
So, the measurement process stops, but the 2 sweeps continue to play.
I get this dialog box (attached) before any audio is played




When I enter the SPL Meter for calibration, it supplies a filtered pink noise signal, not sine wave choice. When I enter the Signal Generator, it doesn't show an incoming signal, just outgoing and "RMS Level dB FS" adjustment. Where do I need to be and what do I need to do to get this done properly?
So, I tried REW again last night - re-calibrated the sound card as well (had a feeling it wasn't done properly and now the response looks less questionable).

Went through "Check Levels" and on to the generator. Played a 60Hz sine (at 2.83v w/cab disconnected), SPL meter & RTA mic next to each other, one meter from the TH. Opened up SPL reader in REW and clicked calibrate. My SPL meter read 104.7dB, so I typed it in and it said the highest I'd be able to measure is 99dB (instead of the 189dB it said before). Am I doing something wrong here? REW is now able to read SPL, so - that's a step forward at least.

Still, when I go in to measure, I click "Check Levels" there, it pops up the "Signal too Low" warning before any audio is played. Then, audio plays for a couple seconds and stops (same happens w/measurement sweep). Maybe I should set up a loop for REW to calculate for sound card delay option.
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