[imran27]

Normally digikey will provide free shipping for orders over certain minimum value. I don't if that applies for Canada or not. You'll have to check it out for yourselves

 

[NymPHONOmaniac]

Normally digikey will provide free shipping for orders over certain minimum value. I don't if that applies for Canada or not. You'll have to check it out for yourselves

Nope man....I need to spend 100$ of Opamp to get free shipping....wanna try the one you suggest but it will make like...20$. Anyway, I will search more...even if ebay and aliexpress make me paranoid about fake OPamp. Thanks for the help.

 

[skwoodwiva]

Okay thanks, I will take note this time....did you know a store that do not charge like 15$ for shipping little Opamp?

True, the stock Opamp of XD05 isnt bad at all, sometime I even wonder if I prefer it to the V5iD....

i would like to find a trustable seller on ebay....I use paypal and like free shipping.

Man all this voodoo chatter, where are the science cops????
Lol. Have I been lost in space...

Hey seriously is there a buf 634-like mosfet?
Opamp? I love (mos)fets. I had a sample it blew me away.

Also my krk vxt6 project, if I go balanced, is the balaclnced architecture maintained throughout?
What kind of bypassing are you all talking about for the sensitive opamps?

 

[FritzS]

I have been told of varied reports on different XD-05 units. My friend bought one from Jaben SG and had horrible results with OPA1692.

I on the other hand had amazing results with OPA1692 and that is my favourite.

When it comes to details and clarity:
- OPA1692
- OPA2209

Gives there any type which are similar to OPA1692 but single channel?

dual ............. single channel
OPA2209 --> OPA209
OPA1692 --> ?

 

[imran27]

Man all this voodoo chatter, where are the science cops????
Lol. Have I been lost in space...

Hey seriously is there a buf 634-like mosfet?
Opamp? I love (mos)fets. I had a sample it blew me away.

Also my krk vxt6 project, if I go balanced, is the balaclnced architecture maintained throughout?
What kind of bypassing are you all talking about for the sensitive opamps?

BUF634 is the output stage aka buffer/output buffer aka current driver

LME49600 is another of such device.

Yes, most probably balanced will be maintained from DAC output to BAL out unless you have a BAL to SE conversion stage but that will be in parallel to the BAL stage

Sensitive opamps need extra supply bypassing. Bypass V+ and V- using capacitor. A 0.1nF ceramic to be bare minimum.

 

[FritzS]

BUF634 looks like Walt Jungs 'Diamond Buffer'
http://www.ti.com/lit/ds/symlink/buf634.pdf see page 10

Walt Jungs Diamond Buffer:
http://waltjung.org/PDFs/Op_Amp_Audio_Buffers_1_ED_090198.pdf
http://www.waltjung.org/PDFs/WTnT_Op_Amp_Audio_2.pdf

 

[skwoodwiva]

My KRK project https://www.head-fi.org/search/8582304/?q=*&t=post&o=date&c[thread]=876953

I still have to digest the rane document...
I could be on the best path? I am not sure.
I ask because an opamp may be a better / latter option...

 

[Rroff]

Sensitive opamps need extra supply bypassing. Bypass V+ and V- using capacitor. A 0.1nF ceramic to be bare minimum.

Yeah - I've found 0.1uf WIMAs to work well for rail-to-ground - they seem to be high speed enough without having to go to ceramics - rail-to-rail bypassing seems to be a bit complicated one and beyond my knowledge really - I've found I can get good results simply by sticking a high quality 10uf aluminium electrolytic close to the opamps power pins but some people have different opinions on that - I know a lot prefer a film cap in that position.

It is also worth in some cases having a LPF on the source input (even just a RC filter) close to the opamp pin - I've found a few opamps people complain about "sounding" grungy or flabby I've no problem when used with that in the equation.

If the opamp is unity gain stable and/or used in some transimpedance configurations having a compensation capacitor in the feedback loop can vastly improve things - can also be done with some opamps that aren't unity gain stable but beyond the scope of my knowledge really.

For some reason I'm not a fan of discrete and/or BUF634 buffers - purely subjective - LME49600 isn't a bad option but can be a bit fussy about the output unless you have the knowledge to properly shunt it when required, etc. :s personally prefer to parallel opamps for buffers - especially as that can allow for stable low impedance output - but even there it isn't a straightforward story with a very limited selection of opamps that can really drive decent current amounts and a couple of them lacking when it comes to things like handling output shorts.

 

[NymPHONOmaniac]

So I pass like....too much hours on ebay trying to figure out wich seller is trustable cause some price for Opamp are just so low its non sens, as well, the look isn't the same so I try 2 different sellers to test their stuffs. One look more trustable than the other and don't receive comment about fake products like lot of others. H'es call xianyeji2016. I buy Muses8820 from him and the LME97720, Both sell at list price but with free shipping.

Other strange one is a dual to mono OPA627AU.

Must begin with something....we learn from error.
Will share impressions once I got these cause I feel Opamp searcher need reliable Ebay (or aliexpress) seller....Headfi hasn't been any help for me in this aspect. And i'm certain not ALL chinese sellers are full of BS.

 

[Mad Max]

I did not know until now that OPA1688 is a rebranded OPA2172.
1688 apparently has better channel separation above 100Hz and better PSRR/CMRR. Looks more like an upgraded version to me that way.
Sweet.

 

[Rroff]

I did not know until now that OPA1688 is a rebranded OPA2172.
1688 apparently has better channel separation above 100Hz and better PSRR/CMRR. Looks more like an upgraded version to me that way.
Sweet.

I wish there was more information out there on opamp lines, etc. a lot of the OPA16xx family seem closely related to various OPA2xxx family opamps i.e. the OPA1612 is basically the same as the OPA2211 except the 2211 is laser trimmed or something for better DC performance while the OPA2209 seems to share a lot with the OPA1602 (and OPA2211) in terms of sound "signature" and doesn't have "SoundPlus" but sounds more refined and doesn't have the slight articulation problem the 1602 has.

 

[Mad Max]

OPA1602 is a bipolar input opamp, unlike OPA2209 as far as I know. I do find both pretty different. Now I've got to give 1602 a shot again with that "slight articulation problem" comment. Haven't touched it in quite some time

 

[imran27]

OPA1602 is a bipolar input opamp, unlike OPA2209 as far as I know. I do find both pretty different. Now I've got to give 1602 a shot again with that "slight articulation problem" comment. Haven't touched it in quite some time

OPA2209 is bipolar.

The only problem I have with OPA2209 is that it is too damn sensitive. It needs a good decoupling to perform at its best.

Another problem is that it's inverting input is slower than its non inverting input (look at large signal responses of both configurations). Which means I would not want to use them in any case where both the inputs are being used like a differential amplifier or summer stage or in some DAC differential amp and I/V are combined (Burson Play for example) so there too I wouldn't use OPA2209 because different speeds of both I puts.

It is however amazing when it is used only in non inverting configuration.

Just yesterday I got my batch of OPA1692. I bypassed my output buffers with Nichicon VZ and damn, this is the kind of sound that's deceptively good. Deceptive because in the first listen you'd be damn sure that OPA2209 is more extended with better tonal balance. But give it some time and you realize that Opa1692 is so clean and has such a dark background that without that brightness and lushness in the background compared to opa2209 you feel it is less detailed. In fact Opa1692 is the most detailed I've heard.

I hope my Play arrives soon so I can 'Play' with it

 

[Rroff]

OPA1602 is a bipolar input opamp, unlike OPA2209 as far as I know. I do find both pretty different. Now I've got to give 1602 a shot again with that "slight articulation problem" comment. Haven't touched it in quite some time

As imran27 says they are both bipolar - 1602 articulation problem is pretty subtle but once you notice it you can't "un-notice" it - shame in a way but the OPA2209 has completely replaced them for me as it similarly has a bit of a textured reference like sound but doesn't have the issues the 1602 has.

 

[Mad Max]

I hear the articulation funkiness in 1602 in my O2 (2068's position).
Oh wow.
My OPA2209 (or rather, 2x 209 on a dual dip adapter) doesn't physically fit in there, LOL!
TL5580 doesn't like the O2. Ends up with an awfully white background. Oh well.
ADA4075 rules. About as good as 1688, but more relaxed. A little less thick, but a pinch more resolving, everything is a bit more resolving with it.
Didn't think that I'd switch out after trying 1688.

Maybe it is a good thing that I went for the regular Teac HP50 (with OPA1652 in DAC LPF) instead of the special edition (with OPA1602 in DAC LPF). hahaha

On a side note, what's the deal with 4075's output impedance curve in the low frequencies? Funky-looking.