PERFECT AMP GAIN SETTING COMPLETELY FREE!!! 

Hands down the best explanation I have heard to setting the gain on an amplifier

I would've never thought that you'd measure HU pre-out on the RCA, and THEN set gains... brilliant. Everyone always says "set your volume to 75-80% to max and then set gains" but I love the idea of matching pre-out voltage. Thank you for this!

Another easy way is use an old small speaker you have laying around attach a small Capacitor to it. Hook it up to your amp, play a 40hz test tone through it and start turning the gain up. Once you hear sound through the speaker (clipping/distortion) simply turn the gain back down slightly till the speaker goes silent again. Bam clean signal every time, try it for yourself. The capacitor will filter out the 40hz tone playing through the amp but allow the harmonic distortion from the clipping to play through it. Free and 100% effective.

Finally someone who actually understands this stuff explaining it to where anyone can understand it. Huge thanks!

Really great concept! The only issue is this assumes that the manufacturer has used a linear potentiometer for gain control - ive seen many using logarithmic potentiometers, whereby half-way up the dial is equal to around 28% or 72% of gain depending how its been wired. Wouldn't it be so much easier if all manufacturers actually labelled the voltage on the dial! :P

nothing against anyone else trying to explain the science behind all this but that's about the best explanation of how thing work I have found that I could understand, thank you for sharing. be safe and God bless!

The fact that you showed 92BT head unit and old MRV amp together is such an unreal find for me. I wondered why my signal is clipping at volume set 20-21 for about a year. That almost driven me to throw away MRV-F405 from my system. I'll definitely try your setting up scheme tomorrow. Thanks a lot!

Bro this is….amazing. For years I’ve used ohms law but that implies the amp actually does rated power. This is insane lol

When measuring AC volts there is no need to observe polarity. You can put the meter leads on whichever you want, it will read the same. DC is when polarity matters. Hooking up the speakers polarity matters so they receive the same wave and work together. Other than that it for anyone to cheap to buy an oscilloscope it looks like some good advice. I'm a firm believer that distortion kills more speakers than slightly over or under powering them.

Great video. I showed it to me Gran. She called it rubbish and pissed off back to the tele. :)

Excellent guide. I will be using this technique to set up my amplifier. Head Unit Single RCA output. 1.5v. Multimeter set to AC to find clean output on RCA in relation to HU volume level. Calculate where 1.5v sits on gain dial. Sony Amplifer RCA input voltage 0.3 - 6v. 6v minimum. 0.3v maximum. Lower voltage position (0.3v) is maximum gain. So lower voltage value = higher RCA input compensation (gain). Hopefully, I understand it correctly.

Thank you for sharing the video. Now the sound produced by my amplifier is perfect.

You are a god, this is the easiest explanation for this I've ever heard.

my new CT Sounds amp(s) dont have a line/input dial. in this case, i just turned my head unit up to 75% of the volume, and checked the output at the speaker terminals. my door comp's can handle 80w RMS. they are 4ohm rated. so the quick math to do is multiply the RMS power rating (80w) times the resistance in ohms (4ohm) then get the square root of that.. 80x4=320 squared, is 17.9 with the head unit volume at 75%, i'd check a/c voltage on one of the speaker terminals and turn up the Gain until it outputs 17-18 volts. *to get this done right, set your EQ, all your sub gains or bass boosts on max because once you turn up the gain, you CANNOT then do a 0-12 db bass boost unless you want your voice coils in your passenger seat :)

Not sure if you had any on your outputs before measuring with the scope, but you must have a load on the output before checking for clipping. Whatever the input impedance is for the amp on the line level outs to your scope and whatever the amps output impedance (prob 4ohm) dummy load on the scope leads. Your way will work but you're losing some of the power capabilities because with a load connected the output adjustments would be a bit higher before clipping.

Man iv heard al this is so many times but God dam it I finally understand thank you sir😂

Awesome. Thank you sir. Cheers from Florida.

Thanks a ton for this! I must be doing something wrong... my head unit spec reads "Low-Level Output (4 channels): 2.85 Volts." With max volume on both Bluetooth phone and headunit, my multimeter reads .6 Volts AC for a 1000 hertz test tone... and vacillates between .7 and .8 Volts AC for a 100 hertz test tone. The headunit tech support (Retrosound) says I won't see full voltage unless "there is a load" such as connecting to an amp. So I tried adding an RCA Y-Adapter (one side to the amp and then onto a speaker... the other side naked). Readings on the naked Y-Adapter RCA plug are the same (.6-.8 ACV). I then measured with an oscilloscope... I see no clipping (perfectly smooth waves) at max volumes (perhaps Retrosound engineered theirs to have

Best instruction video I've seen! Been hunting for tons of information and this video shows everything I needed to know. Awesome video

Fantastic formula that didn't bore me to death with guesses

Great explanation!! Wondering if this can be done using a line out converter as well? I will be adding an amp and sub using the factory HU which doesn’t have any RCA pre-outs. Thanks

Thank you very much break down was awesome and really appreciate how you showed everything rather then just telling me I'm much more hands on type person this is so helpful keep it up please and thank you have a great day

How would you measure the output of a factory head unit to a line output converter? Would it essentially be the same process? On the line output converter I have it has a clip light to set it at the frequency needed if I am correct, please correct me if I am wrong

It's 4 am and I came across this, now I've gotta try this before I sleep and forget this video ever existed

could you make a video with a oem head unit without rca and using a Hi-Lo impedance adapter please

This guy needs an award for the year

Most useful information I have received from RU-vid thanks mate.

Yo Adam was great until you only hooked up the oscilloscope to the amps not the multimeter. How do I use a Multimeter on an amp?

Set your sub out to 1/2-3/4 then do this.. in my experience you’ll get more clipping from the internal gain/filtering of a head unit not the actual volume.. But you got to pair that with the speaker level outs as well if powering speakers off the head unit.. find the balance of clean out and clean rca.. This is a good starting point for just adding a sub but it doesn’t really give you the full picture.. you want clean power to everything it just the sub.. this is why amps have gain controls so you can tune them up or down accordingly to match the rest of the system. But most times the pre out will over run your line outs on your head unit.. I like to start with the line outs and then work from there unless everything is running off amps Can’t believe this doesn’t have more views.. this is one of the easiest to understand and follow videos for beginners But need to know your head unit sub out.. for example mine is 0-14 with -8bd to +8db.. 0db is setting 7. Therefore when doing this with my head unit I would need to be at setting of 7/14 not at max.. This is more often than not the case for most brands.. alpine is the best at giving really good non clipped output at max settings though for most models.. I’d bet your sub out is plus minus too cause most alpines will go max power in clipped to both the preamps and the line outs

hey, that's the same head unit i used to have. I loved it, wish i had pulled it from my truck before i sold it.

I don't get this. The less voltage your car stereo will give, the less you turn gain from your amp? So, in my case, my stereo has 4V output level and my amp has 6V input level I would turn gain to about 2/3 of max. And because my subwoofer is 250W RMS, and my amp is 310W RMS, I probably lose some of the potential of my subwoofer? Or should I use 31.62V instead (square root of 4 ohms x 250W)?

Well done. Love it!

I'm confused on the alpine amp that you said it's 0v to 4v. why does it say 0.5v nowhere near where it should & how the 2v being across from max does make any since if you break it down to % 2v should be straight up where it's says Nom, which I thought was for the most common setting being 2v is pretty common. But I really like this video & how to find the head unit per out put max. Every one else say go 75% of max volume which I never liked.

Quick few questions. 1. What test tone frequencies are you using (I assume 50 hHZ for a sub, and 1000 hz for other channel speakers)? 2. What should I do if at max volume the output measured on the RCA cable is not even half of the indicated preamp output? I am using an Boss BE10ACP. Which states it supplies outputs: 6-channel preamp outputs (4-volt front, rear, sub). When playing a 50 HZ test tone and testing one of the rca cable of the sub I am not even getting above 1.7 at full max volume. What would cause this?

wait I see where you checked the gain on the receiver, but how did you check the clipping one the amp w/o the scope?

Great vid. So what if my HU is stock with all the integration stuff, and I have an amp connected to speaker level inputs. Can I just read the voltage off the speaker wires since my shitty HU has no RCA?

Hey mate, quick question. What you describe at 2:30 is a better way of just setting your headunit at 75% and assuming that is clean voltage, right? Thanks for your video!

Can you just set your head unit to max and your input for music such as an iPod or phone to max. From that point adjust the filter your using (in my case hpf) and gain until it isn't clipping on an oscope and be in the clear?

What test tone u used?

Great video! What equipment are you using to set up your bench to power.the head unit and amps? Thanks

thanks a bunch for the perfect tutorial!

And is your phone at full volume as well?

Damn it man you aced this, thank you!

You really earned me with this video. New subscriber here !!!

What test tone are you using ???

Very well explained

Wait; great advice on measuring the pre-outputs of the radio because I haven’t seen that yet ( I’m a beginner so I’ve been watching TONS) of videos. My question is how do I know what “ Hz “ to set it at? I’m doing a 2 amp setup. 1. Pioneer DX871 powering 2 “12s / 2. Aunex 4ch powering all 4 interior speakers

what test tone do you use to find the headunit clipping?

New to your channel congratulations on the 10000 subs I'm in the same place as you with my channel coming up to the 10 figure I've always been into the car audio seen and watching some of your videos just brought back loads of old memories back so hit the sub I have a setup at the moment running Audison ,focal , jLaudio and alpine

This is a great video, thanks for making this. My Pioneer HU is 4v, and my Alpine amp is 4v at minimum....so I'm assuming my gain should be on minimum?

This is invaluable. So real quick though, doesn't this also mean you cannot turn your radio up past 23 because of the induced voltage excess causing gain distortion?

Soooo at what point are you just going to use the multimeter?

What frequency do you use in this tuning? And does BT never distort at max level from the phone? Can all amplifiers handle max level in without any load, dont you have to put a load at the speaker output, or is it safe to run full gain and max signal in without any risk of breaking the amplifier?

Out of all of the other videos I’ve watched not one of them mentioned anything about measuring the source output voltage volume.

Thank you for a simple video with an easy to understand explanation for doing this. You're the shit

excellent bud

Great video! Quick question, what test tones did you use? 40hz?

Do the same rules apply with a crossover/line driver

so what happen when you use audio control amplifier and on the gain there isn’t any numbers on the gain? but it is 8v input? the signal come out head unit is 5v, so turn up half way and a tad more? also what if you use factory head unit and use high speaker input for signal. how do you determine the factory head unit voltage? this is really helpful, thanks

What if my preout voltage is less than what is specified? Spec is 2.5v but when measured, I only get 1.6v at full volume.

He's not lying about setting your car on fire.

Dude this is relevant aswell to guitar recording in the digital realm, I would need to measure my guitar pickup output to set up my virtual amp simulator input level according to my pickups (meaning, passive and actives have different output etc..) I'm hittin my head against the wall with this thing.

This sounds And looks positive

Wowww dude thanks for this 🤯

the problem ive seen with every single amp gain setting tutorial - no one talks about how songs played clip at different levels. if you play a song from youtube it might clip before the song on your CD. Or from your buddies ipod playlist. Its never consistent. I gave up trying to "properly set my gains" for this reason. Turn the gain up, use a bass knob, and watch for a clip light. at least thats whats worked for me the past 15 years

Cool stuff, waiting for an update on the van. Cheers!

what tone are you playing

What frequency were you using for finding your ac voltage?

Just turn the head unit to 100%MAXX and set amp gains to zero distortion!!.. . I am into SQ installs and this is the preferred way for 0 Distortion Max output.. .

I believe this would be okay but let's say u set it to 5v with a 5v system and u turn it down would that be fine. And also with a bass knob. If you have it maxed out at 5v don't bump the bass knob up? I hear ppl call the bass knob gain control and is just very confusing. Than ppl say gain isn't volume but also say the gain is the volume than call the knob gain. What

Had a question about the tone you okayed and if you had other other speakers hooked up. If I wanna set the gain myself we don’t have audio shops local. Do I need to unplug my door speakers so the Tone don’t play through them since the volume will be up high when testing the rca volts

Does it matter if I set the gains with the car off (12 Volts) or with the car running (14.4 Volts)?

If my pre out is 4v and my amp is 5v-200mv do I set the amp to 5v since that’s the lowest on the dial

Great info thanks !!!!

And this only tells the amp max clean signal.u gotta make sure your subs are the rite ohm load and can handle the amp power if it’s max at its cleanest signal output.can blow a weak sub if amp is too big..

What if your 7sing stock head unit? With hi level input directly on the amp, or using a high level input adapter to rca.

Awesome video, the best explanation on this topic!!! On my setup my base sounds good when I have the input level button out in the high mode per the kicker 800.1 label. Pushed in the base is low like non existing. But I have the rca cables from the headset into the amp. Shouldn’t the base sound in the low setting? I had this installed years back and don’t recall but I think the installer used an inline converter from headset speaker wire to rca converter out the amp because I have the factory headset. Is it that when using this LOC converter even though the rca is going out the amp input button should be set to high level input?

Not a big fan of using compressed audio (Bluetooth) for tuning. Am I missing something here?

What if you use a line driver with higher voltage ratings

This doesnt make since to me. If the input is at the may 6 volts for the 1st or 4 volts for the second your logic says to turn it up 100 percent, full open. My logic would suggest that would be the lowest setting at min. So if the amp accepts 6 volts and your putting 2 volts into it, you should turn it up 66 percent, 2 volts out of 4 would suggest turnig it up 50 percent. So lets say you had 1 volt into the 6volt max input. You would need to turn the gain up 84 percent. Thats why .5 volts was so high on the amp gain, the less input you have the more gain you need to make up for it. This isnt an issue with quality amps that have good signal to noise ratios but some amps can pick up noise with lower input voltages

I will try this cool video 👍

what is the best Gain setting With rockfoord Punch P3D4-12 600 RMS @2ohm

But were are u putting the tester once plugged in 2 the amp 2 know were 2 set the gain on the amp on the speaker outputs ?

Is there a way to do this with an amp with built in speaker level inputs, or just have to hope the manual provides the right info to figure it out?

nice Video .I looked at my radio but I can't find the Volt preouts settings there. It is a Sony dsx 410bt.

??? So could we still use the multimeter at the RcA outs of the amplifier to find where it clips?

Man, this is a great video, but I have a stock HU in my 2021 Mazda 3 hatchback. And I have no idea what the output voltage is, because there's no manual or nothing.

What if my amps input sensitivity is measured in Millivolts? Input Sensitivity (Level 100%): 230mV would be 0.23V? and my headunit is 2v. what would the math be?

So, at only 66% of the Alpine's pre-out signal, it begins clipping? Can't forget that when you wanna "crank it."

How come when I do this to my RCA wire it always says at 0? I have my RCA cables plugged in the the back of the radio. There are a front and rear red and white and then below that two back RCA connectors that say sub. That's the correct place to connect them right?

Question what are you playing through the heaunit..a test tone?

How do you account for the dynamics of different music

What if the amp has no gain markings and cannot find that info from the mfr?

what kind of song needs to be playing ? or just hook up the bt?

My android HU has a built-in subwoofer gain. Should I set it to max before I will perform your video tuning process? I will also set bass boost to OFF and equalizer FLAT on the HU.

So I've I stalled an jvc kwm745 head unit paired with an audison sr5.600. I have looked at the out put of the head unit using an oscilloscope there no cliping at full voltage . Although I have sent the gain to matched the pre out I was thinking is there any reason why I can match it it to the speakers, which are audison rated to 100w rms @ 2ohm. Or set the gain as close to speaker max before oscilloscope shows cliping. What are ur thoughts

What is the head units equalizers set to

Thanks

How do I find the correct voltage for my skar rp1500

R u playing a 0db 40hz tone?