[goodvibes]

Nope. It's on the AK120 as well. I think it does a nice job in noisey environs. In reasonable settings, I avoid the EQ.

 

[kimvictor]

So I wonder if that means the ProEQ setting is just to counteract the most common symptoms of impedance mismatches?

that would be awesome... I'll try with my uerm.

 

[kimvictor]

Nope. It's on the AK120 as well. I think it does a nice job in noisey environs. In reasonable settings, I avoid the EQ.

aww. I had hopes.

 

[goodvibes]

You may like it anyway.

 The AK100 is not as susceptable to load impedance as it's output impedance would have you believe. These tests show no impedance induced deviations from flat.
 

 

 
Crosstalk is affected but 50db is plenty and more than a crossfade circuit at minimum type levels and distortion differences are negligible. There's more to look at in a circuits response than output impedance. Folks like hard and fast rules to make things easy but it doesn't always work out that way.

 

[Loquah]

You may like it anyway.

 The AK100 is not as susceptable to load impedance as it's output impedance would have you believe. These tests show no impedance induced deviations from flat.







Crosstalk is affected but 50db is plenty and more than a crossfade circuit at minimum type levels and distortion differences are negligible. There's more to look at in a circuits response than output impedance. Folks like hard and fast rules to make things easy but it doesn't always work out that way.

How does this relate to the effect on voltage delivered to the earphone drivers? Or is it a different area of measurement altogether?

 

[Vinnie R.]

Quote:

You may like it anyway.

 The AK100 is not as susceptable to load impedance as it's output impedance would have you believe. These tests show no impedance induced deviations from flat.
 
 
 
Crosstalk is affected but 50db is plenty and more than a crossfade circuit at minimum type levels and distortion differences are negligible. There's more to look at in a circuits response than output impedance. Folks like hard and fast rules to make things easy but it doesn't always work out that way.

 
Not true... If you are simply using a fixed resistor (instead of a headphone, whose impedance varies with frequency) then you won't see the problem.  
 
 
 
Quote: (John Atkinson / Stereophile August 2013)

For example, if you look at the measured impedance of the JH16 Pro, this averages 13 ohms in the lower midrange and bass, rising to 35 ohms at 2kHz, then dropping to 12 ohms at 7kHz. This will modify the headphones' frequency response by –2.6dB in the bass and midrange, +1.8dB in the low treble, then –3dB in the high treble. Similarly, the Ultimate Ears 18 Pro average 18 ohms in the lower midrange and bass, and 11 ohms between 8 and 10kHz, rising to 30 ohms in the low treble. With both of these in-ear monitors, this variation in impedance will shelve down the lower mids and bass compared with the low treble when driven by the AK100—but more so with the JH16 Pro than with the 18 Pro, where the bass and lower midrange will be suppressed by 0.9dB and the low treble emphasized by 1.2dB.

 ​

 
 
I hope this helps,
 
Vinnie

 

[Loquah]

Not true... If you are simply using a fixed resistor (instead of a headphone, whose impedance varies with frequency) then you won't see the problem.  





I hope this helps,

Vinnie

Thanks for confirming my suspicions, Vinnie.

I've created a simple spreadsheet to calculate the impact of OI on earphones (so long as you know max and min impedance across the freq range). Just calculates the dB difference that will exhibit between the max and min impedance. Happy to share with anyone if they want it.

 

[goodvibes]

Quote:

 
Not true... If you are simply using a fixed resistor (instead of a headphone, whose impedance varies with frequency) then you won't see the problem.  
 
 
 
 
 
I hope this helps,
 
Vinnie

Yah, I spaced out and assumed those measurements were at the same V with the same overall DB level and there's nothing there that says those were matched as you'd hope. That would indicate it's not an issue but 'that' is not there. At least it doesn't show bass roll but I agree varying impedance phones could represent an issue. Thanks for the correction.
 
The Pro EQ is a fixed setting and in no way could compensate for whatever nonlinearities may be incurred on various phones.

 

[the wizard of oz]

< 0.5Ω
< 700$
< 600$
< 500$
< 400$
< 300$
< 250$
 
Gap-less
WM8740 DAC
14 hours of audio playback time
User-replaceable battery (Samsung S3 model)
Charge via USB or AC adapter
 
iBasso DX50. It's out since a few hours.

 

[oddsocks]

Quote:

Wow you guys are fast! Yes, firmware version 2.20 has been released and is now available to download at these mirrors below. 2.20 brings the Pro EQ preset that was previously only found on the AK120
 
http://www.iriverinc.com/lounge/loungeView.asp?selectPart=&findWord=&sno=1080&page=1&cateCode=
http://www.iriver.com/support/download_view.asp?dNum=1080
 
If you still have problems downloading from our official mirrors, please try downloading at the Dropbox link below:
 
https://www.dropbox.com/sh/9ayf40dosrrntzm/6_ibqRbFC1

I'm having problems downloading from the iriver site, but your dropbox link isn't working Jmoon. Thanks for the update.
 
EDIT: After numerous tries, finally got it off the iriver site....

 

[kimvictor]

Quote:

< 0.5Ω
< 700$
< 600$
< 500$
< 400$
< 300$
< 250$
 
Gap-less
WM8740 DAC
14 hours of audio playback time
User-replaceable battery (Samsung S3 model)
Charge via USB or AC adapter
 
iBasso DX50. It's out since a few hours.

Very interesting. Maybe I'll buy one to compare it to AK100. But for now, I'll wait for user reviews and impressions.

 

[kkcc]

Very interesting. Maybe I'll buy one to compare it to AK100. But for now, I'll wait for user reviews and impressions.

Ordered, and hope to replace my AK120 as my ultraportable with this if the sound quality is somewhat close.

 

[kimvictor]

Quote:

Ordered, and hope to replace my AK120 as my ultraportable with this if the sound quality is somewhat close.

Wow. You have high hopes!

 

[kkcc]

Wow. You have high hopes!

Maybe not as high as it sounds. AK120 is better than AK100 but not really by a mile or sth. It won't be too far fetched to get something sounding close to it. For example I like a modded x3 more than ak100. Re dx50 quoting myself from another thread:

Not necessarily a straight one-to-one trade. My situation is that I also have 901. So the key draw, and use case, for my ak120 is when I want to go really light, need 6+ hrs for long commute, or on days I m not sure I would have a lot of time to listen. Otherwise I find myself always picking up the 901. Therefore in my case it make sense to sacrifice some SQ and recoup 1k or so if dx50 can cut it. Or I ended up sending it to vinnie and keep it as a portable usb dac and transport.

All depends on how much SQ gap I find to see whether dx50 can really take ak120's spot for my usage.

 

[JmoonAK]

Quote:

I'm having problems downloading from the iriver site, but your dropbox link isn't working Jmoon. Thanks for the update.
 
EDIT: After numerous tries, finally got it off the iriver site....

My apologies! Here is the correct link: https://www.dropbox.com/s/1dz3eey6thhuhum/AK100.hex