| Author |
Thread: Setting gain with DMM |
    
Silver Member Username: Iamduff_87
Michigan
America!
Post Number: 266
Registered: May-04
|
| Posted on Saturday, December 11, 2004 - 12:49 am: |
|
Ok i have read on the JL audio website that you can set your gains more accuratly by using a DMM and a test tone cd. i was wondering if anyone knows of a chart for MTX Thunder amps so I can see what the voltage would be. If you look at the tutorial on the JL site it has a chart for JL Slash and E series amps. I have a MTX 311d. If anyone knows that would be a lot of help. |
|
|
|
Gold Member Username: Glasswolf
NorthWest,
Michigan
USA
Post Number: 6232
Registered: Dec-03
|
| Posted on Saturday, December 11, 2004 - 12:03 pm: |
|
generally I use an oscilloscope to accurately set gain, but that JL guide should give you an idea of how to do it if your meter reads "true RMS" values for AC circuits
|
|
| Posted on Saturday, December 11, 2004 - 02:14 pm: |
|
Amp does 200wRMS at 2 ohms...so...
200*2=400
square root of 400=20
set your amp to 20 volts
using the same steps on the JL thingie. |
|
| Posted on Saturday, December 11, 2004 - 02:14 pm: |
|
Amp does 200wRMS at 2 ohms...so...
200*2=400
square root of 400=20
set your amp to 20 volts AC
using the same steps on the JL thingie. |
Gold Member Username: Glasswolf
NorthWest,
Michigan
USA
Post Number: 6254
Registered: Dec-03
|
| Posted on Saturday, December 11, 2004 - 05:25 pm: |
|
there ya go
sorry my answer was brief.
I was getting dragged out the door when I was trying to respond to go look at cabinetry for some remodeling.
|
Silver Member Username: Iamduff_87
Michigan
America!
Post Number: 269
Registered: May-04
|
| Posted on Saturday, December 11, 2004 - 06:23 pm: |
|
oh ok. also the amp says 200wRMS @ 2ohms but thats at 12.5 volts when the car is off
when the car is on i run 14.3-14.4 and is rated at 300wRMS @ 2 ohms at that lvl. should i set my gain at that time ?? |
Gold Member Username: Glasswolf
NorthWest,
Michigan
USA
Post Number: 6275
Registered: Dec-03
|
| Posted on Saturday, December 11, 2004 - 06:37 pm: |
|
yeah I'd set the gain based at above idle so you get alternator voltage. that way you won't overdrive the system at all when the car is running.
|
Silver Member Username: Iamduff_87
Michigan
America!
Post Number: 270
Registered: May-04
|
| Posted on Sunday, December 12, 2004 - 12:25 am: |
|
ok cool. so 300*2=600
square root of 600 = 24.5
is the *2 mean take the RMS and x it by the ohm? |
Gold Member Username: Glasswolf
NorthWest,
Michigan
USA
Post Number: 6317
Registered: Dec-03
|
| Posted on Sunday, December 12, 2004 - 01:16 am: |
|
yes RMS wattage multiplied by the impedance.
|
