The best sounding audio integrated opamps

[leeperry]

I really like LT1113ACN8: Linear Technology - LT1113 - Dual Low Noise, Precision, JFET Input Op Amps

is it unity gain stable please?

it's replacing two OPA2134P, is that OK? 1113 is JFET and 2134 is FET.

[jacco vermeulen]

Originally Posted by leeperry

2134 is FET.

You forgot to add the J

[ianpengelly]

Its worth checking out the new ADA4627-1, which is unity gain stable (i.e. you can use it as a buffer) and sounds great. I got samples from Analogue Devices, so even better because they were free! :-)

[leeperry]

oh ok, I thought it was FET...so is LT1113ACN8 a drop-in replacement for OPA2134P?

doess +1 stable means it's unity stable?

I put two LT1113ACN8 as AK4396 LPF buffer and I was told on another forum:

You can't use not unity gain stable opamps on the HD2, the gain is too low. LT1028, AD797, OPA(2)228, OPA637 etc all don't work or oscillate. The only one's that're stable and I don't know if they're unity gain are AD8022 and AD8397.

It's a voltage out DAC chip (AK4396) so the opamps have a gain of just 1 to supply current and make it single ended. The layout isn't designed to make a gain of 1 good enough for something like the LT1028 and it's never gonna work for uncompensated BB's

anyway, LT1113ACN8 sounds really great..the more expensive their op-amps, the better they sound

[ianpengelly]

Originally Posted by leeperry

oh ok, I thought it was FET...so is LT1113ACN8 a drop-in replacement for OPA2134P?

doess +1 stable means it's unity stable?

Yes, if you look at the very end of the data sheet it shows it used in a unity gain application.

[Mooly]

LT1113ACN8, the data sheet says unity gain stable... but not to use at gains of less than 1

[leeperry]

ok thanks, where did you see this? I must be blind

it says you can add some components around it to make it unity gain stable...that's what I understood anyway..

so if I read carefully the post I quoted about my soundcard...I need to use opamps that are either stable at +1 or unity gain stable(is that the same thing? sorry for the noobish question!!)

and LT1028/AD797 are stable gain <1, so they're no good to me? they were making strange low frequency garbled sounds from time to time tbh...but well using browndogs in a PC case is a terrible idea anyway

so unity gain stable is better for blind op-amp rolling basically?

thanks for your help! I think I'll keep the LT1113ACN8 in there for a while, I love how it sounds

[Mooly]

Datasheet here, second paragraph under "description"
http://www.datasheetcatalog.org/data...0/57393_DS.pdf

Unity gain stable means gain of 1 which is for example a buffer with the inverting input tied to the output.

The AD797 is unity gain stable but only if used correctly... this is why I keep saying to Andre that you can't just drop in devices with no regard to the circuit it's going into, and why it's necessary to optimise for a given opamp.

[amparoytoni]

I want to put a headphones amplifier in to a cd player,

the 30mA of the opa1611 isn´t sufficient to move directly a headphones?

Which buffer, will be adecuate to that o_amp.?

[leeperry]

ok, thanks Mooly...finally some technical details I understand

so I should only use op-amps that are given to be stable at a gain of 1(= unity gain).

I wish I could get the LT1028/AD797B stables, but it seems like a lost cause?

apparently LT1128 might be worth a shot, though? I really miss the 1x28 color as final buffer