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Difference between front vs rear audio?

And after all this discussion, has anyone done the check by connecting front and rear connector to see if there was a difference? I don't think so. And I personally believe that there is no difference in sound quality.

I am using amplification for my headphones, so yeah, difference is big, since i can't raise dBm on front port.
I have insanely good hearing. Top 0.1% according to my doctor. I am no audiofile tho, I just like clear and vibrant sound but no onboard audio has impressed me yet.

If you use cheap headphones, onboard is fine. If you use expensive ones, it you won't get full benefit for sure.

Not many "gaming headsets" goes in the high-end category :)
 
It also depends on the motherboard. Some mid-to-high end boards have a discrete opamp for the front panel, and it makes noticeable difference if you use high impedance headphones.
In OPs case it's even more complicated (if he was talking about his main rig, I assume). MSI MEG X570S ACE MAX comes with ALC4082 codec, but they use ESS Sabre 9018 as a dedicated DAC/AMP for the front panel output. Not sure if it's a good or bad, but it's a "premium" board... so I guess there was some reasoning behind it besides marketing.
 
I have VERY good hearing. I was talking about the average person's ability to hear.

My ability to hear the high pitched coil whine back in the day(and it drive me fricken bonkers) is what motivated the effort to understand the problem, look for and then create a solution.
There isn't really anything to argue about here as has been mentioned by several other people it completely depends on the motherboard, and maybe the case if it uses a really cheap cable to connect the ports.

I don't critically listen to onboard audio from a quality perspective so in my experience there usually isn't any difference to really speak of but there have been a few instances where the front ports picked up way more noise from activity in the system like CPU, GPU load, even mouse movement, the kind of thing you would have to have a hearing disability to not notice. For regular listening, most of the time they sound the same but if the board has a good audio implementation and if you critically listen with good headphones or speakers I'm sure there are differences on most boards. Its pretty much just the nature of doing audio in the EMI nightmare of a PC and having that much longer traces to the front ports.
 
and having that much longer traces to the front ports.
To be fair the DAPs on a lot of boards are usually pretty close to the front header
 
There isn't really anything to argue about here as has been mentioned by several other people it completely depends on the motherboard, and maybe the case if it uses a really cheap cable to connect the ports.
Oh, completely agree. You might have missed comments made in other parts of the thread. No worries.
I don't critically listen to onboard audio from a quality perspective so in my experience there usually isn't any difference to really speak of but there have been a few instances where the front ports picked up way more noise from activity in the system like CPU, GPU load, even mouse movement, the kind of thing you would have to have a hearing disability to not notice. For regular listening, most of the time they sound the same but if the board has a good audio implementation and if you critically listen with good headphones or speakers I'm sure there are differences on most boards. Its pretty much just the nature of doing audio in the EMI nightmare of a PC and having that much longer traces to the front ports.
Also agree there. There are many things that play into analogue audio transmission quality inside a case.
 
Without exception (that I've experienced), FP Audio always will sound worse vs. on-board/on-card, even if very minor.

More often than not, my experiences have been FP Audio being absolutely atrocious! The wires running to the FP Audio ports have 0 mitigation for noise. Most of the PCB's I've seen the FP jacks themselves on, are also antithetical towards Analog Audio quality.

It might be possible to improve EMC (ElectroMagnetic Compatibility) by making your own FP Audio cables using SFTP 4P8C*.
I've been toying with this idea for years, and recently stumbled across an article about EMC improvements running 60hz ('Bass' in the audible spectrum) 120VAC over Hot-Neutral twisted pair (with straight and parallel Ground).

Live-Neutral_TwistedPair_fig4.png


I'd assume pure copper pre-twisted Channel-Ground / Sense-Return pairs surrounded by a foil shield would be a massive improvement. Basically, you're converting Ethernet Cable into multi-channel Litz Wire.
*CAT6A, 8, and 7/7A are most often found in Shielded/Foiled and/or Foiled/Shielded Twisted Pair.
Pin
Number
Pin
Name
Description
1 PORT 1L Analog Port 1 - Left channel (Microphone)
2 GND Ground
3 PORT 1R Analog Port 1 - Right channel (Microphone)
4 PRESENCE# Active low signal that signals BIOS that an Intel® HD Audio dongle is connected to the analog header. PRESENCE# = 0 when an Intel® HD Audio dongle is connected.
5 PORT 2R Analog Port 2 - Right channel (Headphone)
6 SENSE1_RETURN Jack detection return for front panel (JACK1)
7 SENSE_SEND Jack detection sense line from the Intel® HD Audio CODEC jack detection resistor network
8 KEY No pin
9 PORT 2L Analog Port 2 - Left channel (Headphone)
10 SENSE2_RETURN Jack detection return for front panel (JACK2)
Source
You don't even seem to 'need' every pin connected:
CountMike @ TomsHardware Forums - 01/01/2017
Those female jacks have a switch which opens when a plug is inserted.
Only HD audio has that, AC97 standard doesn't so those are left not connected. You can do that too if you don't need sensing, just don't connect 4,7 and 10.
 
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So much bullcrap posters :D But some are good, so there is hope.

Simple answers

1. Front panel is always worse.

The question remains is it audible? Not always.

It is always measurable? YES, it is and you do not even need pro gear for that.

An the answer is also simple. Depends on the load, PC setup and there is no universal answer. You have to measure not do some philosophy.

1. With low Z load. It may be crucial as you introduce excessive wire length that accumulates a certain resistivity with subpar PC quality jacks, I mean it, those are worst quality ones you will ever see. You will loose power due to loss on the cable, with low Z it becomes a significant percentage. GPU radiated EMI is so powerful you will see it the graphs more when measured. Can we fight using coils, twisting cables etc... on certain degree? - no, the radiated power is way too high and everything is way too close. Simply the needed amount for rectification exceeds the case size. If you use an integrated GPU... then YOLO, do as you wish in most cases. The energy is not enough with low Z to hear distortion in most scenarios and that is the most often use case.

2. With high Z load you risk into driving the output in oscillation is more EMI sensitive. It largely depends on the schematic solutions, but considering the low voltage motherboard audio is capable of outputting as such it is a fundamental problem for high Z loads. In general PC is a place where compromises are done and what fits for all fits for nothing. There are motherboards with dedicated DAC's and headphone amps, those are much resistant to anomalies, but not always, you know there are always Gigabyte boards with ASUS following them closely in profanity race.

Cable has a capacity. If the commutation switch(external or internal HDA) is not properly designed it will act as an oscillator, some even manage to to wire up coils and zip tie them when doing beautiful cable management :D. yeah it looks neat, but you ware a nincompoop at physics also. Thing is all tests are done in ideal conditions and without large GPU's. Basically motherboard makers use audio section parts as LEGO bricks and put them on anything, they are not tailored really, so problems may arise due to differentiating current flow in the PCB... Thus why we see different revisions of the same board, especially Gigabyte is known for that(Asus often hides it), some manage to to screw current path on such degree that the it really takes the audio parts as the shortest route also thus introducing audible noises, like hearing mouse movements and GPU revving up like an diesel engine, the signal ground is polluted. We have 300W+ switcher sections like 10-20cm from analog parts... well it is what it is... it is crazy actually.

The use case of front panel audio has stalled in recent years and NO ONE will pay attention to it and will receive no development. In my books HDA header should die. People are already using wireless for years, If not I plug a Type C headphone. The PC case front panel I/O should be be a hub with a dedicated simple audio part, those cost peanuts these days and are decent performers. Case I/O should use only one USB line and that's it, no more clutter and wires, some makers charge us 200$+ these days for a PC case, for what? RGB crap? Put a USB hub, audio/even MIC array and Bluetooth there. Laptops have it, why PC cases should not have the same features and not to rely motherboard have it all and have options, the implementation of it is trivial and would cost under 30€ when doing small batches, on large you can do it under 20€.
 
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