What voltage to set gain to?

[Stu55 0]

So I guess the dmm I had was on the fritz so I tried a different one and I set it to 40 volts, I can't hear the sub work at all. The tone was more noticeable through my door speakers than the sub. The gain setting is maybe a third from the lowest setting at 40 volts, it started at half when I got it out of the box. I had it at 2/3 before. What's the deal?

[jlw*22 0]

Did you check your subs terminals to be sure you are still wiring the sub right. Amps positive to subs positive-then from that coils' negative to the next coils positive and then from that coils negative to the amps negative.

[dbjunior 0]

what was the tone and what is your lowpass set at you should have used a 50hz tone and the lowpass should be set to 60-80hz

[jlw*22 0]

I'm thinking he's got the coils wired out of phase with eachother or a coil is toast.

Edited May 16, 2009 by jw 2 + 2

[jlw*22 0]

You are setting the voltage with the sub disconnected from the amp aren't you?

[Stu55 0]

Yes

I mean when I had it to half it sounded good to my ears, at 40 volts which is a third away from minimum, I cannot hear it.

Edited May 16, 2009 by Stu55

[jlw*22 0]

the difference between the 400 watts and the 500 watts isn't great so the output should not be hindered much. If when you crank it up it gets less output then something is miswired or the amp itself is not set to the proper gain. When you play it and it sounds good check the voltage when its hooked up to the amp at the boxes connection. Then do the same when you have your head unit cranked and it is getting quieter. If the voltages do not change, you may be clipping. If need be turn it up in small incriments to check over and over. This is the only explanation that I see as viable. This isn't going to be a problem for you if it is clipping as you can go ahead and parallel wire that woofer according to the model amp you say you have. Check your amps installation guide to double check that it is 1 ohm stable. It should be according to the model # you gave us. To get 1 ohm simply put the two positve terminals of the sub together with a short wire and put the amps positive in one of the terminals. Mock this on the negatives ( all negatives together). If you do this be cautious and set the voltage to 22.36 volts at 50 hz. Do this when the headunits sub volume control is max and all your bass settings must be at the max of what you will listen too. If you change the bass settings you must reset your gains accordingly. Now be sure again to put the volume of your head unit to 3/4 max and remove the speaker wire from the amp to set your gain.

[Stu55 0]

So wire it like this:

and set it to 22.36 volts?

When I had it to 40 volts, at 48/60 volume it was only moving maybe 1/8" peak to peak.

[jlw*22 0]

Thats right. All positives together and all negatives together. If you want 500 watts go for 22.36 volts. Be sure to listen after setting it up. If you start your volume at about half way and slowly turn up the volume you should hear consistent rise from the woofer without a hitch. If you don't you are in thermal compression or the amp is not capable for any number of reasons. In any case there is only so much that sub can do. If it isn't giving you the kind of output you seek, be ready to spend some change. Good luck.

[Stu55 0]

Hmm, I just found out that the older version of the type r's which I have are only 300 watts rms...

[jlw*22 0]

That probably puts you at a high thermal compression. Is a bigger ported box an option for you?

[KU40 173]

I'd just set it with my eyes and ears and be done. There will be so much variability in songs you'll listen to that, IMO, it's impractical to think that one static setting will work, especially when setting with a test tone. Granted this is where a remote bass knob or sub volume on the HU comes in handy, but I found that I had to turn my gain up farther due to the almost nonexistant bass in some old rock songs that I wanted to hear. I'd set my gain with rap songs, but when I plugged in Def Leppard the bass drum wouldn't be proficient enough even with the sub level maxed out. So I have to know that the sub may reach limits with only +12 out of +15 on my sub level on rap songs.

[Stu55 0]

Yeah that's what I did, sounds good, I take it easy on the volume, and hope that it goes well.

[jlw*22 0]

I'm not sure thats a good idea. I'm guessing that you don't know the difference between the clean bass and the distorted bass. Some people actually like the type of output they have in heavy distortion. Problem is this can be death to the voicecoil. That is why amplifiers come with gain instructions that tell you to use tones (0db tones at that). The rms voltage is basis for preventing destruction and getting clean output for your long life of close to real sonic reproduction. You can set it then check with real music cranked and you will see the voltage actually will go higher than your rms setting in some cases. Thats where them peak numbers come from, the burst impacts. Either way you go, I wish you luck.

[KU40 173]

Don't worry, I can tell the difference between clean bass and distorted bass, especially with the Mag. I haven't blown a subwoofer in 10 years even with amps rated up to twice the sub's RMS.

[jlw*22 0]

I wasn't talking about you. I was talking to Stu. You have experience, he obviously does not per the questions he asked as evidence. I thought this forum was to help people and protect people from making avoidable errors that may damage the equipment in question. Either way, I don't want to give people advice that can end in a bad way for them. Best of luck at any rate.

[KU40 173]

Well I don't disagree with that. I just don't think it's practical due to the wide range of music out there.

But a tip for this method is to open your trunk with the sub playing as loud as you think it is safe to go, and take about 10 steps backward. Distortion is a lot easier to hear farther away from the sub when your ears aren't overloaded. You can also have somebody else slowly turn the volume up inside while you're back there so you can more easily tell when the sub stops being louder and the musical reproduction from the sub changes.

[jlw*22 0]

Well I don't disagree with that. I just don't think it's practical due to the wide range of music out there.

But a tip for this method is to open your trunk with the sub playing as loud as you think it is safe to go, and take about 10 steps backward. Distortion is a lot easier to hear farther away from the sub when your ears aren't overloaded. You can also have somebody else slowly turn the volume up inside while you're back there so you can more easily tell when the sub stops being louder and the musical reproduction from the sub changes.

What are friends for right.