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[chrisgixer]

What is it? How does it work? And why does it make my HK sound a bit scratchy on high hats/symbols and female singers "s's" ....?

Or is it something else?


And Esta, bog off, it's not a misspelt impotance. Ok?

[Andy B]

something to do with resistance .......... 

[Dave DND]

http://whatis.techtarget.com/definition/impedance

 

[chrisgixer]

Wtf? First paragraph. No idea.

[chrisgixer]

See, I can't see it. That's the problem I have with sparks. I mean I can see that that wire has to touch that terminal to make a circuit, and that diet of thing.

But I guess this a type of electricity. () in which case I have no chance.


Let's look at it the other way then. Why is my drive to play emulator a bit "screechy" on high note s noises...? Like some sort of distortion.

TB knows what I mean.


Mean while I will try to digest the link a bit more. Thanks Dave.

[zirk]

Wtf? First paragraph. No idea.

Impedance (Z) has many meanings dependending on its application and use, but for simple Audio terms which is what your refering to its the Z input and output stages or devices, ie an Hi level Amplifier driving some speakers will be designed to drive a speaker set up of similar Z (normally in the low Z range), likewise a Pre Amplifier (low level) will have i/p and o/p Z stages (normally a higher Z range).

Impedance is quoted in Ohms normally against a given level (Voltage) but unlike simple Resistance calculation at a DC Level, Impedance is given at an AC level and will change at a different frequency of the AC (Audio) Signal.

Impedance miss match between devices is common today with people that think everything is plug n play now, ie a typical one I see quite a lot is where so called DJ's or Pub Owners will plug the iPhone Head Phone output or speaker out of DAB Radio (both fairly low Z) into  a Mixer Desk or PA Input (typically High Z) and then expect it to sound right, while adjusting Volume levels to make amends to get the Volume Level correct, this scenario can have a dramatic effect on Frequency Response, ie, too much or not enough Bass ranging to tinny or distorted Mid to Treble notes, as well as messing up Distortion levels, Signal to Noise ratio, Dynamic Range, Headroom, Ambient Noise compression and overall Music Quality..       

[chrisgixer]

Yes the iphone is a bit quiet. So volume turned up a bit to compensate. So I guess the ranges are all to cock.

Just to say though it's by no means intrusive, and barely noticeable on the move. It's a Bose system obviously. Iphone to hk drive and play hard wired via fm to  Ncdc2015

[zirk]

Yes the iphone is a bit quiet. So volume turned up a bit to compensate. So I guess the ranges are all to cock.

Just to say though it's by no means intrusive, and barely noticeable on the move. It's a Bose system obviously. Iphone to hk drive and play hard wired via fm to  Ncdc2015

No idea what a hk drive and play hard is. Sounds like a Driving School in Hong Kong?, do they teach Chinese folk to drive Black Cars? as for Play Hard being wired up to it, probably not something that should be discussed before the 9 o'clock watershed.

[TheBoy]

The iPod connected via the iPod cable to the HK is giving distortion? Shouldn't do, as that is designed to all be properly impedence matched.

When we tried an iPhone via the CD Changer in my Chavmobile, do you recall the distortion/lack of clarity? That was impedence mismatch, and that's often how it sounds.

[chrisgixer]

The iPod connected via the iPod cable to the HK is giving distortion? Shouldn't do, as that is designed to all be properly impedence matched.

When we tried an iPhone via the CD Changer in my Chavmobile, do you recall the distortion/lack of clarity? That was impedence mismatch, and that's often how it sounds.

I do. And yes that's how it sounds. Although slightly more subtle on mine.

[chrisgixer]

It is present on ipod, and iphone. Although iphone has a quieter volume level for some reason.

[TheBoy]

The iPod connected via the iPod cable to the HK is giving distortion? Shouldn't do, as that is designed to all be properly impedence matched.

When we tried an iPhone via the CD Changer in my Chavmobile, do you recall the distortion/lack of clarity? That was impedence mismatch, and that's often how it sounds.

I do. And yes that's how it sounds. Although slightly more subtle on mine.

Admittedly the chavmobile was fairly extreme, for obvious reasons the mismatch was completely out.

[chrisgixer]

But what to do...?


Although it's not the end of the world on mine tbh. I'd far rather have the iPod connectivity etc, than not.

[TheBoy]

It is present on ipod, and iphone. Although iphone has a quieter volume level for some reason.

How is the gayPhone connecting to the HK, presumably not via the iPod connection, as you HK doesn't support Lightning.

[TheBoy]

If its happening with the gayPod via the gayPod connection, I'd suggest you're in the realms of FM adapter deficiencies.

But its been in a couple of years now, possibly more? I vaguely recall doing it, and I must have been pretty mobile, so must have been pre accident (Feb 2012)

[chrisgixer]

It is present on ipod, and iphone. Although iphone has a quieter volume level for some reason.

How is the gayPhone connecting to the HK, presumably not via the iPod connection, as you HK doesn't support Lightning.

Either 3.5 Jack aux in on Hk . Or bt reciever connected to same. Audio is the same with either, and yes the gay phone volume is on max.

[chrisgixer]

If its happening with the gayPod via the gayPod connection, I'd suggest you're in the realms of FM adapter deficiencies.

But its been in a couple of years now, possibly more? I vaguely recall doing it, and I must have been pretty mobile, so must have been pre accident (Feb 2012)

Possibly.

[Magwheels]

Sibilance perhaps?

Maybe the amp clipping?

[DrAndyB]

Ahh impedance 

Think right angle triangles.   . Horizontal is Resistance (real bit) vertical is complex bit (reactance) and long bit (overall Impedance).  So for DC systems only resistance is valid as frequency is zero for reactive bit is zero !  For AC systems there then exists this complex vertical reactive bit which is proportional to frequency ( for capacitive systems the higher the frequency the smaller reactance.  This is why ac signals can pass through a capacitor and DC is blocked.  For inductive systems its the opposite.  That is why power transformers are the size and impedance they are and why 50hz mains voltage works so well.  Any higher frequency and the tranformers "reactance" increases as the vertical bit of that earlier triangle gets bigger so the bit triangle bit, the impedance, bets bigger.

PM me if you need to know more 

I have P.HD in electrical and electronic engineering, chartered Engineer and design the 132kV and 33kV power system for one of the main electricity network companies so know a bit about Complex impedance 

The Dr. 

[Kevin Wood]

I'm going to hazard a guess that your FM modulator is overmodulating and that this is where the distortion comes from. Could also be that it's slightly off frequency. Same result. For the price, it's hardly likely to a masterpiece of frequency stability.

I've noticed by 2006 actually distorts on most proper radio stations, TBH. Combination of poor modulator and / or poor tuner? Could be that the levels into the modulator are too high on the peaks, of course. Does it sound louder than a typical radio station at the same volume setting?

[chrisgixer]

Ooh now that's difficult to answer, as the modulator causes some loss of signal. There aren't many stations left

...but certainly the iPhone is quieter than everything else, for some reason?

[TheBoy]

It is present on ipod, and iphone. Although iphone has a quieter volume level for some reason.

How is the gayPhone connecting to the HK, presumably not via the iPod connection, as you HK doesn't support Lightning.

Either 3.5 Jack aux in on Hk . Or bt reciever connected to same. Audio is the same with either, and yes the gay phone volume is on max.

IME of gayDevices, that in itself can cause a bit of clipping.

Does the distortion reduce if you turn volume down on gayPhone and turn up on HU?

Is this a new thing, seeing as you've had the system several years, if so, whats changed? Is the HK a bit naff, where 2 devices in its 2 3.5mm (does it have 2 x 3.5mm jacks, or have to bodged something in  <<<  This is where impedence mismatches will occur, eg, you're plugging in phone by 3.5mm and BT via the same input)?

[Dave DND]

I was also about to suggest to turn the iPhone volume down to less than half and then turn up the volume on you other devices

Does this improve the quality - if so, you will have to find a happy volume setting where the iPhone can be turned up and the main device turned down - keep playing until you have found a good setting.

When this has been done, pat yourself on the back, as you now understand how impedance works

[chrisgixer]

The distortion, minimal as it is, has always been there. No change, and it's the same on all devices that input the hk. Might point to the hk being the cause...?

There is only one aux in via 3.5 jack. Other input is iPod cable only. The volume and distortion on the aux in is exactly the same if via iPhone bt receiver to hk aux in. Or without bt receiver. There is no audible change in using the bt reciever that I have noticed so far.

Will fuddle with volume settings on the way home

I presume there's no immediate fix or box of tricks that can be fitted in line and balance things out? I'm sure one of you guys would of mentioned it by now.


As I say though, it's no biggy, has been so since instalation, and has not got any worse. It's only the addition of the bt receiver that has upped my usage and prompted a few questions. In fact, the iPod i'm using make more noise  than the interference as it's an old 3rd gen with a herd disc that can actually be heard spinning up at the start of each track. but I know what the cause and cure is for that (buy a compatible solid state iPod) so not worried.

It was more a case of understanding the fault with this impedance business.

[zirk]

There is only one aux in via 3.5 jack.

I presume there's no immediate fix or box of tricks that can be fitted in line and balance things out? I'm sure one of you guys would of mentioned it by now.

Far from it,

[zirk]

There is only one aux in via 3.5 jack.

I presume there's no immediate fix or box of tricks that can be fitted in line and balance things out? I'm sure one of you guys would of mentioned it by now.

Probably also worth pointing out when playing with Mobiles, is the Jack input and outputs dont follow normal Headphone or Audio line level rules, the likes of Nokia, SE, Samsung etc, so dont suppose iPhone is any different, have there own Tip, Ring and Sleeve connections on the Jack or Socket, mostly in the form of Background Resistive Pads or Capacitor Loops in the cable or jack plug mould in order to tell the Phone what to do or what to expect when that cable is plugged in.

Example on Nokias, put a 100 ohm resistor pad on one of the Rings to Sleeve and the Mobile goes from sending out Headphone level at 20 Oms and switches to RCA Line Level at 1K, add another resistive pad somewhere and the Mic pin sends Video out on it, and other R pads or Cap Loops elsewhere and you can control Answer, Hang Up, Music Shuffle, etc all down the same plug.

So worth remembering when plugging in line jacks willy nilly, etc, whilst you may get some noise out of them, might not be the correct noise your after, especially when plugging the leads in to other devices with unknown input impedance.

[Marks DTM Calib]

Resistance is a basterdised version of Impedance for those who only understand DC systems.

In reality, impedance is actually what it sounds like, the electrical 'impedance' of an electrical path but in this case it considers the full frequency spectrum and not just DC.

And that's where it gets interesting as all items will have a different impedance at different frequencies......and when I say all that's everything from a basic piece of wire through to a transistor or speaker......

[TheBoy]

I presume there's no immediate fix or box of tricks that can be fitted in line and balance things out? I'm sure one of you guys would of mentioned it by now.

No, due to the nature of the problem. Unless somebody has made a specific iPhone 5 to HK matching device.

[05omegav6]

I presume there's no immediate fix or box of tricks that can be fitted in line and balance things out? I'm sure one of you guys would of mentioned it by now.

No, due to the nature of the problem. Unless somebody has made a specific iPhone 5 to HK matching device.

Which will presumably be different to the box required when the iphone 5 becomes an iphone 6

[TheBoy]

I presume there's no immediate fix or box of tricks that can be fitted in line and balance things out? I'm sure one of you guys would of mentioned it by now.

No, due to the nature of the problem. Unless somebody has made a specific iPhone 5 to HK matching device.

Which will presumably be different to the box required when the iphone 5 becomes an iphone 6

Who knows, the design may be simialr enough for it to be no issue.

Gixer - do you have an alternate MP3 player (not Apple) that you could fire in the HK 3.5mm, and report back?

[chrisgixer]

Aye? Non CrApple MP3 player? No waaaay

[DrAndyB]

And ironically, the SI unit of Resistance / Impeadance is ........



Ohms, !!!  or the more familiar capital greek letter OMEGA !!!!!!! What else 

[chrisgixer]

HK diagrame.

http://www.manualslib.com/manual/642606/Harman-Kardon-Drive-Plus-Play-Hk-Dp1eu.html?page=5#manual

[TheBoy]

HK diagrame.

http://www.manualslib.com/manual/642606/Harman-Kardon-Drive-Plus-Play-Hk-Dp1eu.html?page=5#manual

Now, had that been a circuit diagram....

[TheBoy]

Aye? Non CrApple MP3 player? No waaaay

Still got the N95, the only phone to out-gay the gayPhone? Or beg/borrow/steal, in order to try to prove if its crApple being a bit shite.