The best sounding audio integrated opamps

What on earth has Andrea done to get banned ?
Over at Head-Fi he's been banned for quite a while. I think there have been several issues like having strong oppionions of things he's never heard and sending uncalled-for PMs to members (including myself). He's shown up again and again under different aliases until he started these threads here.

Maybe we should have a "The Wild Opamp Rollers Thread" where everything's allowed.

Banned for liking opamps? Some of them sound damned good. One really has to work hard to beat the top shelf ones like AD797 and OPA827.
 
Over at Head-Fi he's been banned for quite a while. I think there have been several issues like having strong oppionions of things he's never heard and sending uncalled-for PMs to members (including myself). He's shown up again and again under different aliases until he started these threads here.

Maybe we should have a "The Wild Opamp Rollers Thread" where everything's allowed.

Banned for liking opamps? Some of them sound damned good. One really has to work hard to beat the top shelf ones like AD797 and OPA827.

Well, I hope that was the reason. because if He got banned just because He likes a kind of amp...that is uncalled for!. I like gainclones LM3875 from Peter Daniel (Audiosector) and I also love my new nxv200 amp kits from Anthony (Aussie amplifiers). so if you see me I got banned...Now you know is because I said I like these amps lol. I see you later (I hope lol).🙁
 
hello i`m having problems with lt1028 i picked up today

they are working in a usb soundcard i designed and built (custom pcb etc.)
the circuit looks like this: pcm2706->tda1543->opa604 i/v stage (set up like in the datasheet) -> 2.2uF wima mkp -> 49k dale / 50k shunt pot -> lt1028

previously i had opa602 and it worked flawlessly but sounded not so good
lt1028 sound really great but at certain volume levels (changed by the shuntpot) i get a little hiss or distortion in the background and it gets on my nerves

supply voltage +/- 15V
3.3uf+0.1uF both wimas from +V/-V to gnd as near as possible
gain of 8
non inverting configuration

any suggestions? i tried putting a 22pf np0 ceramic between ni input and output and it seems it works but at the same time it seems to kill everything i like in the sound this opamp produces

any ideas? i can post schematics/photos if it helps
 
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
 
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.
 
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