The best sounding audio integrated opamps

[ianpengelly]

Originally Posted by leeperry

ok thanks for the explanations!

so you can replace op-amps by pricey transformers huh

he's usually using Burson op-amps and already tried pretty much every op-amp in the book, I'd trust his judgment

I wonder if he has tried this:

Audiotrak Prodigy HD2 Sound Card

[KLe]

Originally Posted by Mooly

What on earth has Andrea done to get banned ?

Hmmm, banned ... amazing, and no reason given

[kranius]

Originally Posted by ianpengelly

I wonder if he has tried this:

Audiotrak Prodigy HD2 Sound Card

he surely did. he used to sell standard hd2 w/

- 3x Burson Dual Opamp
- 7x 25V 470uF Panasonic FM (PSU filtering)
- 5x 35V 470uF Panasonic FM (" )
- 6x 16V 4.7uF Sanyo Oscon SH (" )
- 7x 1uF Vishay MKP1839 (opamp/chip decoupling near the pins)
- 7812ACV +12V regulator instead of standard 9V
- 7912ACV -12V regulator
- LT1086 +5V regulator for DAC analogue supply
- 4x 470pF WIMA FKP2 for high/low pass filtering
- 4x 10V 220uF Panasonic FC signal coupling

now there's only the hd2 w/ huge transformers

Source PC | Gooi PC's

[SY]

Originally Posted by KLe

Hmmm, banned ... amazing, and no reason given

Yes, there was. And he's been serially banned from (seemingly) every other audio forum.

Sin Bin

[KLe]

Originally Posted by sy

yes, there was. And he's been serially banned from (seemingly) every other audio forum.

ok ...

[Slash47]

Originally Posted by bichi

Appears that he/she did:
- removed differential/LPF/buffer opamps.
- removed coupling capacitors.
- connected audio transformers to AK4396 DAC differential voltage outputs.
- routed transformer outputs to card's RCA audio output jacks.

In otherwords, transformer provides DC blocking/isolation, impedance matching, and LPF functions.
- guessing output level is lower than stock.
- typical transformer coupled topology. (of "no-opamp" ilk.)
- tradeoff appears to be increased noise and THD. (long signal wires in noisy PC environment.)

Power Section:
- replaced various power filter capacitors with OSCON.
- replaced onboard 5vdc voltage regulator(s) (for AK4396 DAC) with external shunt regulator.

Amplimo TM20 Signal Transformer:
- 30Hz - 25000Hz
- price: approx $114.00 USD

- Ouput level stays the same.
- Noise is fixable and dependent on the pc itself. This is a bit of a non-issue if you take care with your layout, components and settings.
- THD is pretty much the same as stock.
- The shunt regulator is just as close to the AK as the stock IC regulator. It's not 'external' I'd say.

[nyonron]

if anyone is interested i stabilized lt1028 using progressively bigger fkp wima capacitors between the overcompensation pin and the output (soldered directly on the dip8 package)
330-470pf is more then enough
the sound is miles better comparing to a capacitor in the feedback loop but only a 22pf value in the feedback was enough to make it stable

[ClaveFremen]

Originally Posted by SY

Yes, there was. And he's been serially banned from (seemingly) every other audio forum.

Wow!

Andrea managed to start a new opamp thread at diyhifi (which hosts some people banned here) the 4th of February and has been banned the 5th...

A new world record?

[Mooly]

Originally Posted by ClaveFremen

Wow!

Andrea managed to start a new opamp thread at diyhifi (which hosts some people banned here) the 4th of February and has been banned the 5th...

A new world record?

He also managed to set up another account here under a different name for all of 5 minutes, also on the 5th... just long enough to send some PM's before being banned.

[peranders]

Just a reflexion: Andrea talked about taste and replacing opamps. This is like talking about how good "surströmming" is to a person that either haven't tasted it nor will.

BTW: Surströmming is yummie, once a year at least
Surströmming - Wikipedia, the free encyclopedia
Surstromming--One of the World's Strangest Dishes
Surstrmming - fermented Baltic herring