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XSVTOYZ

gains and other questions please help

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ok so I read this forum and fixed my own problem

I was not clipping because of low voltage  (lights dimming)  I was low voltage from clipping the snot outta my woofers. I didnt kill either of them but could smell the sweet smell of the glue getting hot  so I turned em way down and still making good noise and no voltage drop   ?

 

no dd1 and no oscope I do have a dmm    so Im figuring these jbl gtx 500 easily do rated   there is a dyno run that shows near 700 watts

so I was thinking  ( I know bad) 

40hz tone and set to 30-31v should get me near enough to 500 on each at 2 ohm and avoid clipping myself to the poor house  but get me close to getting my power out of the 2 

does this seem feasible?

another question

I have a pair of boxes that are vented but these amps lack infra sonic (sub sonic)  so I was thinking of sealing them up

not really worried about output for the moment    they are a bit muddy sounding out of the port and I hope to tighten this up 

what do you guys think?

thanks for any replies   yeah I am bumping on the cheap!

 

 

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How does a DMM avoid clipping?


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a dmm gives a base line of output  same as they used to  do before the cool tools

I was hoping by setting the max watts it will out put then I can avoid over running my power limit

same effect as an oscope just not able to verify the sine wave

if I can do the math 31.6 is  500 watts   by setting under the max at 30 flat I can at least have some confidence

puts me in the ball park of 450 each  

its better than just guess

 

 

 

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It's not better than just guessing. No matter what they used to do, and what a lot still do, it's still just a guess. You're assuming that amp is clean to 500w. Maybe it did good on someone's dyno video, but not every electronic component is the same from your amp to that one. How do you know when your HU begins to distort the signal? Then there's the 40hz tone you are using. How did you source it? Is it clean? Is it attenuated, if so, how much? There are more factors to a clipped signal than amp voltage output.

 

Check out the SMD tool map to see if there is someone local to you who has an oscilloscope or DD-1. It's a much better feeling to know when the signal distorts. 

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On 1/2/2019 at 7:35 AM, reedal said:

Use multimeter to find the output ac voltage of each amp while playing a tone (40hz is what most use) after youve set the gain where it needs to be (clean undistorted setting), and then to match them, use the amp showing the lower voltage as your reference and turn the higher voltage amp gain down to match. 

No slave if not strapped. Both will need to be set to master.

isnt this you from jan 2?  

I am not a fool   nor a punk kid 

was an ase master and have had several systems  only smoked 1 woofer in my 54 years of age

never have had a dd1 or oscope to set my gains,  not really ready to chase one down either 

just wanted a little confirmation of my plan

your earlier post confirms what I wanted to know "it will  work  fine"

pionneer nex 5000 at volume  30/42  should be clean and at 30v  on the jbl gtx I should be clean

Steve Meade did the dyno run and I am sure he didnt give the gold 2 thumbs up for kicks

I really would like  a little input on the sealed idea as well

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That should work fine. No disrespect to Steve and his products but the DD1 is not error free, if I did more amp tuning I would probably buy one, as most devices are not so use what you have at your disposal and do the best you can. I would say also learn to listen to what a sub sounds like when it is playing distortion that will help. 

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1 hour ago, XSVTOYZ said:

isnt this you from jan 2?  

I am not a fool   nor a punk kid 

was an ase master and have had several systems  only smoked 1 woofer in my 54 years of age

never have had a dd1 or oscope to set my gains,  not really ready to chase one down either 

just wanted a little confirmation of my plan

your earlier post confirms what I wanted to know "it will  work  fine"

pionneer nex 5000 at volume  30/42  should be clean and at 30v  on the jbl gtx I should be clean

Steve Meade did the dyno run and I am sure he didnt give the gold 2 thumbs up for kicks

I really would like  a little input on the sealed idea as well

Gain matching and setting the gain properly at clean undistorted are different things, which is why in that quote i said "after youve set the gain where it needs to be (clean undistorted setting).  Setting each amp to its max clean undistorted setting (using proper signal measuring tools) and then lowering the gain of the amp with higher output voltage (measured with any meter that reads AC voltage) to match the lower output amp is a very safe practice. 

No one called you a fool or punk kid, nor did i say anything disrespectful. I only provided my insight to setting gain via dmm. I do hope that you now understand the difference between gain matching and setting gain to output a clean signal.

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As for sealed, you didnt mention what sub(s), but most manufacturers provide specs for both sealed and ported enclosures. You can stick to those or try a free modeling software such as WinISD to see how your response will be with different enclosure sizes to ensure it responds closer to your liking.

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sorry if I came across a little but hurt   my apologies 

I am gain  matching as well  both the gtx 500

I just dont like to borrow anything also my tool box walked out the garage before xmas ggggrrrr (hate thieves)

I know its old school and not exact    it will require a little feel and some attention to what I am doing but I just want to protect my investment as best I can  and still enjoy my hobby  

 

the boxes are old kicker slim boxes and skar audio vd-10 stuffed inside  they work great with the jbl gtx 500 

500w rms amp 500w rms speakers     just no low pass filter and the low lows are muddy sounding

I am broke and I have less than 0 wood working skills so box building isnt something  I can do, but I can make a plug and seal the boxes!!

 

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