I tried that after some time and set it to 99dB (meter was at 1....meter) - "Maximum SPL with this calibration is 189 dB". Tried measurement again and got the same dialog box.
Breaking things down to the input side I would go through REW SPL calibration and just use the REW SPL meter to verify the mic input is correctly receiving sound, your voice should register...
I'm tired, your on a Mac right?
You can also see the input in the Mac SysPref>Sound>Input there is a bar graph meter that will show input level for the device.
I'm tired, your on a Mac right?
You can also see the input in the Mac SysPref>Sound>Input there is a bar graph meter that will show input level for the device.
My sound card nor digital console have mono/monitor. I believe the "L" input knob was turned down, but I didn't check. Nothing was connected to it.
I feel bad for flooding this thread with my REW problems 🙁
You don't happen to have AIM/iChat, do you?
this indicates the input sensitvity is set way low, turn it up till you are @ ~130 max. The mic is not good that high anyway.
Yeah, Mac. OK, I'll double check this weekend, hopefully.
Due to the amp set for 2.83v testing. I'll do this in the daytime then. But, I'm sure my neighbors would've loved a 130dB 60Hz sine at midnight 😛
I'm sure this is the problem. You just need to turn the knob up on the mic input, no need for loud noises. 1-2v output is more than enough as you are simply calibrating the REW sensitivity/REW SPL meter to match your handheld.
Once this is set, you are SPL cal'd until the input knob is moved.
I normally don't have chat on in gmail. I sent you an invite, you are welcome to iMessage face time or call, but not tonight I'm about to crash it's 5AM on my end.
Once this is set, you are SPL cal'd until the input knob is moved.
I normally don't have chat on in gmail. I sent you an invite, you are welcome to iMessage face time or call, but not tonight I'm about to crash it's 5AM on my end.
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Hi Crenscendo,
I am lurking,SO keep on talking REW,I am a nubbie with it and it helps seeing your solutions,
I built a better mic for mine based on wm-61A capsule,Digikey has them and
I used BC560 transistors, I have RTA measurements from 20 to 20K, Try here
Bill Wall's DIRECT APPROACH - Microphones ECM-8000 has the wm-60a in it ,
Have good day,It's raining in Texas,lol
NS
I am lurking,SO keep on talking REW,I am a nubbie with it and it helps seeing your solutions,
I built a better mic for mine based on wm-61A capsule,Digikey has them and
I used BC560 transistors, I have RTA measurements from 20 to 20K, Try here
Bill Wall's DIRECT APPROACH - Microphones ECM-8000 has the wm-60a in it ,
Have good day,It's raining in Texas,lol
NS
Looks like he turns a measurement mic into a vocal & instrument mic - interesting, but not really what I'm looking for for this purpose.
" 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.
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?
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
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...
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.
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.
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.
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.