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I think a linear volume knob would be awkward to operate...

But can you actually hear any difference in sq due to the higher SNR at the lower gain setting? Isnt SNR so high on modern hifi that its way below what a human can actually hear anyway??
You misinterpreted my entire quote :p

Not linear knob, I know most of them is log based. I meant the increments over a certain range worked logarithmically but the top end of scale somehow was boosted above the logarithmic steps.

By SNR here, I was referring to RFI and EMI. The ratio between the "external" noise and the signal strength in the cable (voltage) would determine the SNR. A lower voltage in the cable would mean that the amp would amplify any noise present as well much louder since the ratio would be lower.

...and yes. It can be very audible.
 

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The part about: "No music is recorded at 0dBFS anyway" is becoming outdated. Try google the loudness war :)

I really don't care horseshit if my system clips above 45 because I nor anyone I know will never play it that loud. So if i'm not losing real world SQ (volume corrected blind test anyone?) I will keep my gains so that I do not have to turn the knob 2-3 turns just for normal volume.
I'm very aware of the loudness wars. No "competently recorded" music reaches 0dBFS anyway, if it does someone has really screwed up in the recording process and it will sound like crap anyway.

We're not talking about "gaining SQ" here. We're talking about reducing the possibility of noise in our systems. If there's noise present (even low amounts) in the signal cables to the amp, the amplifier will amplify the noise in a GREATER AMOUNT. Regarding hearing differences, I'd take on that challenge any day (if there's even a small amount of noise, it will be audible as soon you increase the volume. Especially on quiet portions of some songs)
 

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With no dedicated pause or mute button on the 80prs (havent integrated the remote in my steering wheel yet)I already find it a little irritating when I have to turn it all the way down from about 30, so I think I would find about 50 very annoying.

Before I moved my tweeters to the onboard amp I could sometimes hear a faint noise when listening at night in total silence with my ear very near the tweeter on certain mp3 files... But after i'm using the internal amp I can't hear ANY noise at all except when my phone rings. Will lower gains/higher voltage on rca make the noise from my phone go away?
 

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I think the gains on my old fosgate punch 150 is still at the factory setting, 32dBV !
According to the manual this is correct for most 500 millivolt sources, so I guess my 80-PRS is able to drive it into clipping even at a very low volume setting...
I think I will try the min. gain setting, if it is better I can live with having to turn the volume dial a little more :)
 

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I guess thats the difference between SQ and SPL...
But your nick is golden ear? If you use all the power from you amp it will have lots of distortion, how can someone with a golden ear stand that?
I would rather listen at half the volume with near zero distortion and no power compression etc. than have my hearing damaged from the high spl and distortion from an amp at full power...
And these days you can get great amps dirt cheap, just find the old proven sq amps used!
I have just sold a Ground Zero titanium 1200w amp...
[email protected] 10% distortion!! It may be 1200w and 1 ohm stable but the distortion is 10%!! No thank you not for me!
@1000w the distortion is "only" 1%! Would you also try to max your amp if you knew for sure it behaved the same way?
And how different do your amp behave at full power??

Maybe I'm just old...
I didn't say I want to use an amp to the point of distortion. I said that I want to use all of an amps usable power. That means power available before distortion. If that means 130 watts to my tweeters (which is what I currently have) then so be it. I just don't see how putting 400 watts to a tweeter is going to make it sound any better or play any louder if the tweeter is rated for 50 watts. I'm sure there is something I'm missing because I'm no electrical engineer. :)

10% distortion would be terrible. My JL HD amps are rated at .03% distortion. From what I've learned the human ear cannot discern 1% distortion or less. Once again I could be wrong.
 

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actually, 10% distortion is not terrible, depending on the frequency and the duration of time when distortion occurs.

10% distortion is certainly audible, but if it's only at the very top of waveform peaks, or I should say signal peaks, then the duration is not very long at all and people will have a very hard time hearing it.

This is light clipping, when the majority of the sound is powered cleanly and an amp only momentarily clips. It's also when you are finally getting at the threshold of too much power, or not enough money.

I believe that speakers that can handle music program peaks of several hundred watts, can also absorb the occasional square wave signal's dirty power, which is why it's perfectly okay to run your amp into an occasionally clipping level as far as that goes.

the main issue is when you set a volume level that has 30% or more distortion, which is distortion over much longer duration and clipping becomes a negative.

the setting of the volume is what is killing the speakers, because if you can hear the distortion it's not "just barely clipping" anymore. That's where people tend to get in trouble, they listen for distortion, and if it's not too bad or disrupting their enjoyment of the song, they think it's okay for the speakers, but that's about 20% more distortion than what is acceptable.
 

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"Distortion" is such a wide concept to begin with. EVERYTHING that deviates from the source material would be 'distortion'.

Clipping creates a great deal of non-linear distortion. Depending on the symmetry of the clipped waveform, it consist of mainly even or odd order non-linear distortion. Odd order distortion is widely considered to be more offensive than even order. Unfortunately, most solid state amps will mainly create odd order HD/IMD when it clips. The audibility of this non-linear distortion is a complicated matter, steady state distortion is more audible than transient distortion for example. It's also frequency dependent (might even be level dependent according to Gedlee), generally the non-linear distortion might be audible from 1-10% (completely arbitrary numbers here) depending on condition.
 

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I didn't say I want to use an amp to the point of distortion. I said that I want to use all of an amps usable power. That means power available before distortion. If that means 130 watts to my tweeters (which is what I currently have) then so be it. I just don't see how putting 400 watts to a tweeter is going to make it sound any better or play any louder if the tweeter is rated for 50 watts. I'm sure there is something I'm missing because I'm no electrical engineer. :)

10% distortion would be terrible. My JL HD amps are rated at .03% distortion. From what I've learned the human ear cannot discern 1% distortion or less. Once again I could be wrong.
130w is a lot for tweeter, take care of your ears man :eek:
Can the rest of your system keep up with the tweeters output at 130w ?

I drive with my dog in the car 99,5% of the time so I don't play very loud.
My ears are already a little damaged at high freq's because I worked for years selling ice cream, so I don't wanna damage it any more.
 

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130w is a lot for tweeter, take care of your ears man :eek:
Can the rest of your system keep up with the tweeters output at 130w ?

I drive with my dog in the car 99,5% of the time so I don't play very loud.
My ears are already a little damaged at high freq's because I worked for years selling ice cream, so I don't wanna damage it any more.
I wasn't aware that selling ice cream was bad for your hearing. Lots of screaming kids eh? xD

Sent from my Samsung Galaxy 3 via Tapatalk.
 

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130w is a lot for tweeter, take care of your ears man :eek:
Can the rest of your system keep up with the tweeters output at 130w ?

I drive with my dog in the car 99,5% of the time so I don't play very loud.
My ears are already a little damaged at high freq's because I worked for years selling ice cream, so I don't wanna damage it any more.
The rest of the system keeps up perfectly because I use a dsp to set the levels of all the speakers. On the Pioneer hu in that car I rarely turn it up past 15 and that's when I'm alone. It's the family car so usually it's closer to 10-12 on the volume. ;)
 

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But someone here on DIY told me that to maximize S/N I should adjust my gains so that my headunit is almost at max (about 60) when I play really loud. But you say your system plays loud with the volume at only 15? The Voltage on your rcas must be really low.

Selling ice cream is bad for the ears because you have to constantly ring a very noisy bell!
 

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But someone here on DIY told me that to maximize S/N I should adjust my gains so that my headunit is almost at max (about 60) when I play really loud. But you say your system plays loud with the volume at only 15? The Voltage on your rcas must be really low.

Selling ice cream is bad for the ears because you have to constantly ring a very noisy bell!
maximizing S/N ratios, is really only important if you're getting equipment noise, or hiss from the install.

if you've got quiet equipment, you can have your amp maxed out at 250mV, which on a 5V deck, might be 30% of the way to the stops, and not hear noise.

that's the key, is if you encounter noise, you have enough available voltage to set the floor above it. You may never need more than 250mV of voltage, if your amp can max out at that level.

In the old days, 250mV was an actual max level on some equipment, Alpine wasn't much higher at 500mV. That means that their tape decks used to put out 500mV on their pre-amp outputs, that's it! Amps used to adjust from 100mV upwards to 1V, that was a common range on the gain controls.


and they didn't all have noise!


So when you feel like you need to drive your S/N into the ground by pushing 5V of line-level into the amps, it's possibly not necessary. But if you have it, some say go ahead and use it.

Myself, I choose convenience before noise floor concerns, but if I had hiss, I'd probably think differently about it.
 

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Thanks for the info!
I was getting the feeling I was losing sq but not running my headunit rca near 5V, But I really like to have my max usable volume around 30 instead instead of near 60. I was also wondering if the high s/n was required in a somewhat noisy car environment...
So your info has convinced me that since I can't hear any noise at high volume when the music is silent, even with my ear against the tweeter, windows up and engine off I don't need the higher voltage from my headunit.
 

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WinWiz...

I think what needs to be remembered is that music is dynamic. There's dips and peaks that may require a burst of energy in order to play. Due to differences in recordings, sometimes those peaks can be clipped with your current gain setting.

https://documentation.apple.com/en/finalcutpro/usermanual/index.html#chapter=52%26section=5%26tasks=true

I am aware that music is dynamic. I like pink floyd and some of their recordings are very dynamic.
I also like trente møller, the track chameleon from the last resort is a challenge to almost all amps and speakers. Seems to use a lot of power even at low volume. I once had a fan cooled class A technics amp and the chameleon track would make the fan spin like nothing else :)
 

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The rest of the system keeps up perfectly because I use a dsp to set the levels of all the speakers. On the Pioneer hu in that car I rarely turn it up past 15 and that's when I'm alone. It's the family car so usually it's closer to 10-12 on the volume. ;)
I dont think you understand my question about the rest of your system being able to keep up...
What I meant was that the sound pressure from a tweeter feed a 130w signal, I assume we are not talking 130 walmart peak watt but true sustained watts, would require insane mid and bass power. If your dsp lower your tweets to match the output of your mids you are actually wasting unused power by feeding your highs 130w !!
Personally my tweets gets about 2x14W, my mids gets about 2x80w and my sub about 2x150 but I still has to lower the tweets to match the rest of my system.
So basicly if you don't have like 600-800w on your mids, I don't think you can use 130w tweeting power to anything but brag.
But of course this gives your tweeters a very big overhead :)
 

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First up - I'm firmly in the 'less power will blow speakers' camp, partly because of all the technical reasons here - the net RMS power to the speaker being basically full rail voltage in the case of extreme clipping, the start-stop motion being implied on the speaker cone (momentum notwithstanding).
But mostly it's because of simple human nature - we're going to want it 'xx' loud, and will turn it up until we perceive loudness - either in the form of some distortion as others have said (an underpowered system), or until there's sufficient real SPL that we call it loud enough (a well-powered system).

From my real-world experience: In pro audio we usually put the same amplifiers for the entire set of drivers, with possible exception of subs. Take your typical line-array that you'll see at any amphitheatre or arena. Each box I'm most familiar with has 2x 15" drivers (rated about 600 watts each), 4x 8" drivers (around 150 each), and 2x compression horns rated 75 watts each. Remember these values are real power per driver - most tweeters that we're all buying for car audio are rated something like 90W @ 2.5kHz 12db/oct. I'm not going to do the math, but given the power/spectrum above 2/5kHz, that tweeter is probably getting 10W or less of real power. Anyhow - back on track, for a box like this we would want an amp with minimum 1500W at 4 ohms, preferably 2000.
Why? Transients! As long as the mix is clean, and even with modern techno, etc., the bulk of the power is still around 15-30% of the peaks.
But here's the reason why we also want that much power AVAILABLE to the horns (tweets) - Slew Rate, and an 'easy' load. Slew rate is the rate at which an amp can get from 0V to full output power. So, a 10 watt amp, powering a 4 ohm load, needs only be able to ramp up 6.3 volts in .1ms to produce a 10kHz transient. But, a 1000 watt amp needs to be able to ramp up to 63 volts in the same time. The upward curve of that sine wave is steeper - ie. the higher powered amplifier is essentially capable of higher frequency response at lower output levels.
When properly tech'ed, systems will allow the occasional blink of a clip light, but nothing prolonged, and I have never seen a driver powered as such get blown. This includes sending near-clip levels to those horns (transients!). If nothing else, consider that a pro-touring company just can't have drivers getting blown on a regular basis - the system has to work every night, flawlessly, and this is how they do it.
The other reason for such power is something I haven't seen yet on the speaker-wire discussions here (and please don't berate me if so - I'm still getting around)...damping factor. This is the ability of the amplifier to induce and fight momentum. Basically, at a given voltage, given the impedance curves, you would expect there to be a given current as based on ohms law. But since the coil is moving, there is always 'back voltage' (there are those who can go into the engineering of this). Bottom line is that the output stage /transistors/mosfets/whatever in a better amp can push and/or absorb more of that current in order to better move the driver exactly the way it should be. Bigger amp = more capability to do that.
All that said, it does come down to how the rig is tech'ed, and whether the person driving the rig is using the power intelligently, or pushing it into ear-bleed.
I have seen a few 18's lit on fire because of excessive clipping on rigs that I was not responsible for!
Last nut not least - several people have referred to Post #37, referring to compression being equal to clipping. Wrong, except for in the first few milliseconds or less, or with absolutely stupid settings. Compressors work like very fast monkeys with little volume controls in their hands. When they see a wave come through that exceeds the threshold (not clip, just a predetermined threshold), they turn down the volume. So yes - a tiny bit of 'over' signal may get through (remember I said we let rigs run with the occasional blink). The following bunch of waves will then have had their volume reduced below the threshold. When the monkey no longer sees full-scale waves for a certain amount of time (the release setting), he will start to turn the volume back up to nominal. Getting these settings right is one of the arts of audio. But - if someone sets stupid short attack and decay times, then said monkey will be working fast enough to trim each and every wave, thus making it into a squared off wave. Ok it's a cheesy analogy but factually correct.
 

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Mapletech, I have some pro audio experience, sound crew for a couole of popular 80's metal bands, and agree with how PA's should be setup and run. Doing that, I also have never cooked a cabinet. I wish that 12v audio would more easily allow these kinds of " over powered" setups. The main problem that I run into is the actual amperage requirements are tough to meet in the vehicle. I know the SPL crowd can get into some very complex charging systems, but they are just not practical in SQ cars. Jusy MHO though. This thread is a good one and I like the debate. For me this is year 30 around audio and I am still learning something new every day.
 

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Fair point about the amperage, and as is almost always true, the real solution lies somewhere in the middle. I wouldn't expect that any sane person would set up their rig with all 1200 watt or whatever amps.

To literally put my money where my mouth is, I've just finished purchasing, and am about to start my own build, which is based on a JL 600/6, so 100W will be going to each of - Rear Coax, Front 6.5's, and yes - Front Tweets.
 
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