[Spacehead]

Quote:

Originally Posted by ROBSCIX /img/forum/go_quote.gif I never thought he LT1028's were very good either...actually I have an entire array of Linear tech opamps and I only use them once in awhile. Some people are drawn to the "colored" type of opamps as it hide certain aspects of their gear, either source or cans. To each their own I guess.

I tried lt1364 too and noticed that Linears have their own signature. It was different. Like technical, somehow colored. I guess they are better for high impedance headphones. LT1364 had very low dc offset btw.

I am very fond to Analog's op amps. I am now listening directly to AD8620 and it really shines, even to 32 ohm phones. Little distortion at high volumes but it is very soft rounded distortion that actually causes less listening fatigue than very low distortion!

I cannot listen National op amps. Burr Browns are ok, but too messy bass. Texas are too metallic.

 

[joe_cool]

Once you reach a high level of quality reproduction the synergy of components becomes important.

 

[ROBSCIX]

Quote:

Originally Posted by Spacehead /img/forum/go_quote.gif I tried lt1364 too and noticed that Linears have their own signature. It was different. Like technical, somehow colored. I guess they are better for high impedance headphones. LT1364 had very low dc offset btw. I am very fond to Analog's op amps. I am now listening directly to AD8620 and it really shines, even to 32 ohm phones. Little distortion at high volumes but it is very soft rounded distortion that actually causes less listening fatigue than very low distortion! I cannot listen National op amps. Burr Browns are ok, but too messy bass. Texas are too metallic.

Well circuit and playback gear are part of the equation. Linear tech doesn't really aim their products at the audio market. That is not to say that their opamps don't sound good to some. I didn't mind the LT1364 as a buffer in a DAC or the LT1057. There are others I like more of course but they are reasonable IMO. The AD8620, AD8599 are some good audio opamps and get high praise by those that have been rolling for a long time.

 

[leeperry]

Quote:

Originally Posted by Spacehead /img/forum/go_quote.gif I cannot listen National op amps. Burr Browns are ok, but too messy bass. Texas are too metallic.

yes, National opamps make my ears bleed

ah well, I can't stand OPA211ID anymore...it's got to go! majkel says he believe it plays the tones and harmonics separately...I dunno wth it does, but after trying really really hard, I cannot take it anymore. its strange SS simply cannot make it up for the rest.

try 2*LT1363, this sounds really amazing! but it gets boring after a while...OTOH, I never seem to get bored of LT1028AC, but the more it goes the more I think that I cannot be happy w/ one single opamp...I used to love AD797B as DAC LPF + LT1028AC as buffer + NJM4580 to flood my phones...killer combo!

 

[ROBSCIX]

Quote:

Originally Posted by joe_cool /img/forum/go_quote.gif Once you reach a high level of quality reproduction the synergy of components becomes important.

Very true, some components just do not play well together.

 

[Spacehead]

Quote:

Originally Posted by leeperry /img/forum/go_quote.gif but the more it goes the more I think that I cannot be happy w/ one single opamp

do you have an op amp keychain?

I could glue them together with epoxy and then drill a hole into it. I have about 5 specials that are burned or broken.... what a nice idea!

 

[leeperry]

yeah yeah yeah, back on 1028AC! this chip makes you feel good about life, who needs tubes?

vocals sound just as HD as can be, far more texture and body than OPA211? everything's so tight and entertaining

Quote:

Originally Posted by Spacehead /img/forum/go_quote.gif do you have an op amp keychain?

the Prodigy HD2 soundcard allows you to roll 2 dual opamps for AK4396 LPF, one more dual for buffering and it's got a soldered NJM4580V on the HP out..so you can finetune combinations to get the best out of each of them, a roller's dream

 

[buz]

Quote:

Originally Posted by Spacehead /img/forum/go_quote.gif do you have an op amp keychain? I could glue them together with epoxy and then drill a hole into it. I have about 5 specials that are burned or broken.... what a nice idea!

I used to have an epoxy encoated 486 die as keychain. Shame I lost it years ago... Would be nicer to take a few dies I guess

 

[ROBSCIX]

The older dimm module keychains seem to be all the rage for awhile.
Still testing out some discrete opamps on the side here. Any of you guy been playing with an of those?

 

[Spacehead]

I don't have any experience on discrete op amps.

Now I got AD8022 working on my portable partially SMD built CMOY that has a buffered ground channel.

R4 and R3 are 48K and 15K, R2 is 12K so input impedances are matched.
2.2 uF and 0.1 uF ceramics on power supply pins.

Supply voltage only 8.9V now.

AD8022 amazed me instantly. I thought that, Damn, this is pure music! There seems to be nothing extra and nothing is missing. I don't know as transparent op amp than this. There is very good output current capability for driving headphones directly. Distortion is very low. I have listened to AD8022 before on my X-FI and I am familiar with this bipolar op amp sound. It is very clean and reveals the sound of my headphones very well. I these Philips SHP 2500 phones are actually quite dark.
I think AD8022 would be the op amp if I needed to pick only one.
It has quite discrete sound. It requires good power supply decoupling or it starts to oscillate. And resistors need to be very close to op amp pins. Maybe this AD8022 is too bright? Highs start to fatigue me now a little. Or then I am listening so critically.

I just got 6x1.2V AA batteries charged, so with them I can power this little amplifier for a very long time.

 

[leeperry]

Scott Wurcer posted several schematics for discrete opamps on diyaudio, he said you could make them for a couple of bucks

 

[Spacehead]

Quote:

Originally Posted by leeperry /img/forum/go_quote.gif Scott Wurcer posted several schematics for discrete opamps on diyaudio, he said you could make them for a couple of bucks

I think IC op amp cannot be beaten by a discrete one. It is just physics.

But of course, My Own DISCRETE op amp would sound so awesome, I think!

AD8022 needs some smooth op amps to ground channel and to source so that it doesn't sound fatiguing. Now I need to change OPA1642 for something else.
I wonder if I could get OPA2613 working too, it has insanely high current output and sounds fine, while working on very low voltages.

I posted pictures of this mini smd cmoy to post your builds thread. oh, I need to picture the underside too.

 

[leeperry]

well, the discrete advocates like to remind us that an IC opamp is a big as a grain of rice, and is just a nasty compromise towards SQ...this is parly true, but thankfully you can find expensive and fantastic sounding IC's like AD797B/LT1028A etc...they really don't have anything to envy to good discretes IMHO.

OTOH, a $0.1 5532 sounds like ****..it just does

and the IC advocates like to remind us that all the components and soldering points you see on those discrete opamps *are* in your audio path...and ideally you'd want your audio path to be as short as possible, duh!

but some ppl like tubes, and their distortion is up through the roof

so different strokes for different ppl I guess...and due to the new toy syndrome, what you are thinking today might/could/will change (completely?

) after a few days/weeks/months.

I've listened to all the discrete opamps from A-GD/Burson, and to most of the top range IC's from TI/LME/AD/LT....LT1363 was great for a few days, because it can give you the feeling to be in the studio cabin right before the singer, but it's VERY colored...there's no "perfect" opamp anyway, you need to find the one w/ the less drawbacks to your ears

I've been told great stuff about AD845KN, and I see that a bunch of expensive DAC's are using it: Harmony Design DA9 - DAC [English]
Quote:

audiophile-class AD845 opamp

my usual chinese seller can provide me w/ two of them for dirt cheap...I'll keep it in mind! Andrea loooves it, majkel says it's terrible

 

[Spacehead]

Quote:

Originally Posted by leeperry /img/forum/go_quote.gif well, the discrete advocates like to remind us that an IC opamp is a big as a grain of rice, and is just a nasty compromise towards SQ... and the IC advocates like to remind us that all the components and soldering points you see on those discrete opamps *are* in your audio path...and ideally you'd want your audio path to be as short as possible, duh!

I didn't think about the fact that actually op amps aren't designed for audio only. That is the fun of this, searching for the ultimate op amp

Do you ever think how your music goes through some dirty solder joints and possibly long thin wires and gets ruined this way? It is just ugly.

OK, I plugged that OPA2613 to that smd cmoy and set voltage to +12V on LM7805 regulator.

OPA2613 sounds quite similar to OPA637. Not as delicate but smoother than AD8022 for example. I think about 50 mA current output is enough for 32 ohm headphones because I cannot hear any difference in distortion or bass when compared OPA2613 (350 mA) and AD8022 (50 mA).
Maybe I should remove the output resistors, I have 10 ohm there. But they are for op amp stability. Some say that output impedance should be very low for good sound. OPA2613 would have 0.01 ohm output impedance but my output resistor ruins that.

 

[pulsar08]

Can I use my opa627 and ad8610 on adapters and ad823 which I bought for my pimeta v2 safely in my little dot I+? I read somewhere that fet input opamps are more fragile so I don't want to kill them. I've tried lt1364, lme49860, opa227, ad8599, and opa2132 I would have to say I prefer the opa2132 the best so I was thinking the opa627 would probably be amazing.