Headphone amp with 0.000021% distortion

[peranders]

[quote author="xvlk"]
So Total Harmonic Distortion is a very poor indicator of sound, unless the -shape- of the distortion is specified or known. [/quote]
I'll guess you hit the head with the hammer here. Compare distortion between "average" opamps and current feedback amps. Quite a difference here. Some people don't like CFB amps but I do.

 

[Rochey]

heya peranders...

it's good to see you had some success with the part - that PCB looks V.v.v. professional too.

If you need any extra help with TI product drop me a P.M - my job at TI is to support nordic customers

Cheers

R

 

[adrianh]

Those parts are huge they are 0805
Try 0402 or 0201.
The 0201's are smaller than a grain of pepper!
It is all day long under the microscope baby!

 

[peranders]

[quote author="Rochey"]heya peranders...

it's good to see you had some success with the part - that PCB looks V.v.v. professional too.

If you need any extra help with TI product drop me a P.M - my job at TI is to support nordic customers
[/quote]
Hi!

Just wondering: What is the difference between your line drivers with the same package and TPA6120? Can't see any?

Why haven't you stated the input offset voltage, input bias currents and input offset bias currents? Those parameteres are extremely important especially in this case because they are so large? Those values are mentioned with small letters in the evaluation board documentaion.

Anyway, I asked your company about this (got no answer though) but at least you called me! Gold star for this. An another billion dollar company has nobody at home when I really needed them (don't say which but it was non-amercan company). All american semiconductor companies I have been in contact with have excellent support.

 

[PRR]

> Those parts are huge they are 0805 Try 0402 or 0201. The 0201's are smaller than a grain of pepper! It is all day long under the microscope baby!

NIC COMPONENTS CORP

 

[mcs]

[quote author="adrianh"]Those parts are huge they are 0805[/quote]
I prefer the 1206 types. They are still small, but I can handle them with my big fingers...

Best regards,

Mikkel C. Simonsen

 

[peranders]

...big fingers? You should not use your fingers, use a tweezer instead :grin:

 

[peranders]

I have made some distortion measurements with the free RMAA software and my rather poor soundcard Canta Cruz Turtle Beach.

0.0058% at 39 ohms load and 0.0065% with Sennheiser HD545. Otherwise pretty good results. I will upload the results later.

 

[peranders]

Test results can be found here
http://www.sjostromaudio.com/hifi_files/qrv/qrv07_testreport/QRV07_HD545.htm

 

[tk@halmi]

[quote author="peranders"]Test results can be found here
http://www.sjostromaudio.com/hifi_files/qrv/qrv07_testreport/QRV07_HD545.htm[/quote]

How come the Sound Card has higher distortion in (I am assuming in a loopback configuration) than measuring through the headphone amp? Am I reading this wrong?

Thanks,
Tamas

 

[peranders]

You must have control over gain and levels a bit more and you must also know how these numbers are calculated.