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Murphy8166

Ever wonder how much voltage your Iphone generates.

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Murphy8166

Been doing some bench testing of certain electronics and I figured I would throw a 1khz test tone on my Iphone 4s and see what it threw out. Used VAC setting on my multimeter.

This test was using the 3.5mm jack on top of the Iphone and measured on the other end of the cable which was RCA.

Tested at a couple volumes:

16/16 = .935 volts

15/16 = .662 volts

14/16 = .418 volts

13/16 = .297 volts

12/16 = .187 volts

11/16 = .134 volts

So at the 80% volume level the Iphone puts out .297 volts.

Next test will be the bottom connection of the Iphone...need to find the cable :)

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hethj7

Interesting, but to answer the question, no, I have never wondered how much voltage my iphone generates. :D

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WakingMeHappy

The only time I ever wondered how much voltage something had was right after I got shocked.

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Bobby Light

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skyskier

No one who gives a damn about sound quality would use the top jack. The way more meaningful numbers would be for the bottom jack that eliminates the phones pre amp circuit. However, I get that you were messin' with what you had access to at the time. You pretty much said as much. I would truly be curious to see the numbers from the wide bottom jack. The bottom wide connector on my ipod gives better than expected sound quality with the gains at a modest setting. I suspect it is a fairly strong signal. Don't know if the signal strength between ipod and iphone is similar. I would pull out the multimeter if I was not such a slack a**.

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Murphy8166

No one who gives a damn about sound quality would use the top jack. The way more meaningful numbers would be for the bottom jack that eliminates the phones pre amp circuit. However, I get that you were messin' with what you had access to at the time. You pretty much said as much. I would truly be curious to see the numbers from the wide bottom jack. The bottom wide connector on my ipod gives better than expected sound quality with the gains at a modest setting. I suspect it is a fairly strong signal. Don't know if the signal strength between ipod and iphone is similar. I would pull out the multimeter if I was not such a slack a**.

I have a feeling that the voltage coming from the bottom will be the same as the 75% or 80% number that comes from the top. If you tap into the bottom it automatically sets the volume to around 3/4 of the max which is probably the "best" clean and unclipped signal. I will have the cable to test the bottom this weekend...it is in the boat.

Will have results over the weekend

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Murphy8166

Found an extra cable in the stereo box and tested it.

From the bottom of the Iphone 4s using a Stinger IS76 cable the voltage for a 1khz test tone was measured at .744 volts. It was a little higher than where I thought that it would be.

I have been experimenting with adding a two channel line driver prior to my black box...

Next test will be measuring the voltage on the front output of the Black box with a boosted signal from an Audiocontrol Overdrive and without.

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Nitrousbird

Found an extra cable in the stereo box and tested it.

From the bottom of the Iphone 4s using a Stinger IS76 cable the voltage for a 1khz test tone was measured at .744 volts. It was a little higher than where I thought that it would be.

I have been experimenting with adding a two channel line driver prior to my black box...

Next test will be measuring the voltage on the front output of the Black box with a boosted signal from an Audiocontrol Overdrive and without.

Do you have a Lightning equipped device with an Apple 30-8 pin adapter? Curious on the voltage using the adapter vs a native dock connector device.

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Murphy8166

This is the cable that I am using...http://www.bestbuy.com/site/isimple-switchplay-a-v-docking-cable-for-select-apple-devices/6449806.p?id=1218737497266&skuId=6449806

Not sure if that lighting adapter would make a difference....the phone does what it does, IMO

Edited by Murphy8166

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Nitrousbird

This is the cable that I am using...http://www.bestbuy.com/site/isimple-switchplay-a-v-docking-cable-for-select-apple-devices/6449806.p?id=1218737497266&skuId=6449806

Not sure if that lighting adapter would make a difference....the phone does what it does, IMO

The Lightning adapter may make a big difference. The Lightning connector is a digital-only output. The adapter takes the digital signal and converts it to an analog output. The adapter itself determines the voltage output and not the phone.

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David

The Lightning adapter may make a big difference. The Lightning connector is a digital-only output. The adapter takes the digital signal and converts it to an analog output. The adapter itself determines the voltage output and not the phone.

If the adapter takes digital and converts it to analog, it must contain a DAC. Are you positive this is the case? Analog is also available from the bottom port. At that price, and without an external power source, I wonder if the DAC (if truly contained) would be any substantial improvement in either quality or voltage. I'm just asking and honestly do not know the answers.

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Murphy8166

Not sure that I can test this lighting device.

From the looks of it, it plus into the bottom of the 8 pin port only found on Iphone 5 or newer. I have a 4s.

Here is some info I found on a MacWorld review:

Speakers and audio docks: I tested both adapters with a range of dock-cradle speakers and audio-focused standalone docks using the iPhone 5 and the latest iPod touch and nano models. For playing audio, the adapters worked perfectly with every speaker dock and audio dock I tested, both old and new. This includes newer speakers and audio docks that grab your player’s digital-audio (specifically, USB-audio) output and then use a digital-to-analog converter (DAC) in the speaker or dock itself to produce an analog signal.

But the adapters also work with speakers and docks—generally older models—that require an analog-audio signal. These speakers connect to dedicated analog-audio pins in the 30-pin connector, relying on the iPhone or iPod to handle the digital-to-analog conversion. The challenge here is that the Lightning connector doesn’t offer analog-audio pins—the new connector is all digital.

The solution (and likely part of the reason that Apple’s adapters aren’t cheap) is an actual DAC built into each adapter. In other words, the adapter is converting the iPhone or iPod’s digital-audio output to an analog signal and then sending that analog signal to the appropriate pins in the 30-pin connector. As an example, thanks to Apple’s adapters, I was able to use the latest iPhone and iPods with Logitech’s mm50 speaker system, an old favorite from 2005.

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Earmark Marine

I have done quite a bit of experiementing with iPods looking for the "best" sound quality from an iPod. I've come to some conclusions that are based on my experiences, but as with anything opinions may vary.

First, if you're using an iPod as a source unit (instead of running it into a radio) you will definitely want some sort of preamplifier. Yes, you can simply run an iPod-to-RCA cable (like the iSimple IS75 or IS76) into your amplifier and it will play just fine. But the preamp voltage is very low, as Murphy pointed out (less than 1 volt). There's also the matter of running the iPod "volume" up higher which causes the already too low preamp signal from the iPod to clip.

So iPod as a source unit = use a preamp. It can be a standalone preamp/line driver, or it can be built in to an equalizer that has an "Aux" input. Either way I would prefer something with a varialble level control as opposed to just a fixed preamp line driver, but any preamp is better than no preamp.

Next, there are various opinions as to which particular iPod "sounds best" based on the digital-to-analog converter/audio chip in the iPod. Not all iPods and iPhones use the same audio chip. Apple generally uses audio chips made by Wolfson or Cirrus. The "online experts" don't all agree on which sounds best. I believe that the Wolfson chip iPods, particularly the iPod 5G with the Wolfson WM8758, is better sounding that others that I have experimented with. But I try not to get too caught up in this particular detail. There are a variety of other factors that affect the sound, including what is in the signal path between the audio chip and the output of the iPod, and everything else downstream from the iPod. Plus the program material.

Then there's the subject of the sound quality of the iPod's internal digital-to-analog converter versus using an outboard DAC. In any high end audio system (home, auto or marine) I would suggest an outboard DAC, and even then there are a variety of options. I probably wouldn't sweat these small details (which audio chip, which DAC, etc) on a wakeboard boat audio system simply because the environment of a wakeboard boat isn't an ideal audio listening environment and there are other factors that will make a much bigger impact on your sound quality before you start splitting hairs about digital-to-analog conversion (like a proper preamp voltage and good setup and gain structure).

If you want to get really high end sound from an iPod you have to start with the source material. You will never get "good" sound quality from an MP3. It's a lossy compression and you have lost part of the music when you convert an audio file to MP3 format. No matter how high of a bitrate you use it's still lossy compression and it will never sound "good" to my ears, but obviously "good" is a subjective and relative term. In a wakeboarding boat my goal would be loud and clean, with no distortion. So lossless music files (FLAC, ALAC, WAV, AIFF) will take up more space on your iPod but they will give you superior program material.

Good lossless music files on an iPod that's run into a good preamp, with a system with well tuned crossovers and a good clean gain structure should provide good sound on the boat.

In my personal car that I drive every day I took it a bit further. I use HD Tracks, which is better than CD quality. CD's are recorded at 44.1 kHz 16bit. HD Tracks take the music from the original studio masters and the tracks are provided at 96 kHz 24 bit or even 192 kHz 24 bit. So the music is recorded at a much qigher resolution than a CD, which results in better dynamics and a more spatial sound stage. But only if you have the audio system to support it, with an environment in which to listen to it.

I take the 96 kHz 24 bit music out of the iPod into a Pure i20 iPod dock which I disassembled and hid in the car. The cable runs into the console, so my ipod is alway srun through the i20 DAC. You can buy the Pure i20 on Amazon for about $100 and you can use it in your home system with the supplied wall transformer or in your 12-volt system if you buy or build a step-down for the voltage to use it in the car (it needs 9 volts DC). The i20 has RCA outputs, a coaxial S/PDIF output and a TOSLINK fiber optic output.

From the i20 I run a fiber optic cable to my sound processor (which has a fiber optic input) and from my processor I run Cat6 cable to my amplifiers, which have a digital input section. So my entire signal path is digital and my music is better than CD quality at the source. My component speakers are run active, with digital time alighment to all drivers. With 1/3 octave graphic equalizers on each independent driver and time alignment it's a very good sounding car audio system. I have the tools to properly set the gain structure at each step in the signal path, and after using the electronic tools to set gain, levels and time alignment I spent some time with an RTA and a variety of good music to set the final equalizer settings. There is no piece of equipment that can replace a good ear when it comes to tuning a system.

Odin

Earmark

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Wakesetter67

Some of my friends thought I was nuts when I said my Older Gen I pod sounded better then my new one, Looks like from the above post I was right, They don't all sound the same, I use a ZLD and that works great for my system, I do plug the jack into the top of my ipod sound awesome,

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Murphy8166

Some of my friends thought I was nuts when I said my Older Gen I pod sounded better then my new one, Looks like from the above post I was right, They don't all sound the same, I use a ZLD and that works great for my system, I do plug the jack into the top of my ipod sound awesome,

There is an article floating around out there that goes over the different generations of Iphone and the sound processor they use...I need to see if I can find it.

I agree - never noticed a difference b/t top or bottom of ipod. The thing I like about the bottom of the ipod is that it locks in the volume creating one less variable when it comes to tuning and playing the stereo.

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Wakesetter67

I would assume I could get the Bottom attachment cable But if there is not any sound quality difference then I will just leave it, I set the Volume on my Ipod to just a little over 3/4 volume.

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Murphy8166

No benefit that I can hear sound quality wise.... And I just did my physical and nailed my hearing test!!!

Very debateable topic as you can imagine.

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Wakesetter67

That's the nice thing about products like a ZLD totally adjustable, to fine tune what ever I use, Ipod, Iphone etc.

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