The Opamp thread
Apr 30, 2014 at 10:38 AM Post #4,696 of 7,383
Install it, turned it on and I go, "What a waste of time and money this was." Lows were missing, highs were clear to the point of being shrill, mids nowhere to be found. If it needed breaking in, I doubted it would ever recover. Having the DIP 8 socket installed, I begin digging for some old standby opamps to checkout and discover I have two 49860NA in the mix. Go check the occupied DIP socket and confirm it is a 4562NA sitting in it and grab the eBay $5 special yellow handled opamp tweezer/removers and install the 49860NA and turn the system back on.


 


The difference is between night and day. Clarity with clean highs and lows and mids mixed right in between, nothing really stands out unless there is a flute playing or bass drum hit. Vocals are clear and true. If I am missing warmth or am hearing sibilance, hard to tell, may be the recording(s) but the great detail adds to the separation (staging).

 

Not even sure if this is a sarcastic or a "true hifist" message...
You do realise that LM4562 is pretty much same as LM49860NA, but with higher maximum voltage range and manufacture year?
If you actually managed to find differences, either of those opamps is probably fake and thats why it might sound a little different.
 
Apr 30, 2014 at 4:20 PM Post #4,697 of 7,383
Not even sure if this is a sarcastic or a "true hifist" message...
You do realise that LM4562 is pretty much same as LM49860NA, but with higher maximum voltage range and manufacture year?
If you actually managed to find differences, either of those opamps is probably fake and thats why it might sound a little different.

Here is some older discussions at DIY about this opamp lineup which I guess includes can variations. Seems the 4562 is a bit temperamental and could suffer from oscillations in the wrong environment which I am trying to avoid like with the 5532D and confirms the 49860 might be somewhat weak or not warm in the mid range but to my ears is crystal clear with the highs, for the lows I have an AD 8066AR handling those duties.
 
The 49860NA is labeled LME, 'E' for enhanced, whatever that means. I admit I have many opamps from Chinese/Hong Kong and anything is possible involving knockoffs. I also have a sub with BASH surround circuitry that will amp up the preamp input signal to an audiophile level where I can hear subtle differences via some decent speakers. And my starting point is a PCI sound card AUDIOTRAK Prodigy HD2 ADVANCE DE with LME 49990 on adapters buffered by LT1028ACN8 on an adapter. Checking my old notes, I have the LM 4562NA down as 'flat but true across the range' from previous sound card testing. It could be the 4562 just didn't like the position it was put in this time around.
 
May 27, 2014 at 10:49 AM Post #4,699 of 7,383
I've tried to get rid of a single genuine MUSES01 (obo $60) in this thread and it's like nobody trusts buying from people in this thread,
 
Jun 5, 2014 at 12:37 PM Post #4,700 of 7,383
Hello all,

I really know nothing about opamps but would like to learn. I purchased the Leckerton Audio UHA 6S.MKII amp and it came with 4 sets of opamps. I have attached pictures of them. It appears they are the following opamps.

OPA209
AD797ANZ
LME49990MA
OPA627AP

Would anyone be able to tell me what to expect from them, or what characteristics they are know to have? Im still knew to the audiophile thing. I havn't spent much time with them, and so havn't noticed much differance. Im using the OPA627AP in my amp right now with my iMod and Beyerdynamic DT 880 250ohm cans. Thanks for the education guys! Im doing a lot of learning via the search function as well.

Sorry for the quality, the pics were taken with my camera phone :xf_eek:

sa4e4y6e.jpg

y6a9a3yn.jpg
 
Jun 5, 2014 at 5:46 PM Post #4,701 of 7,383
there's hope if you're really interested in learning - hanging with your buds in this thread, looking for positive social feedback however...
 
if subjective evaluation is your focus then http://www.linearaudio.net/images/LA%20Vol%202%20Yaniger(1).pdf should be required reading - and practice - you really need 2 complete "blueprinted" (trimmed to exact same gain/frequency response, at least better than 1%, ~ 0.1 dB) systems/circuits to do real listening tests - and a blinding protocol
 
it also wouldn't hurt to learn enough electronics to recognize different op amp applications in audio circuits, have schematics of the equipment you want to mod - know the circuit conditions like source, feedback and load impedance, how these change "optimum" op amp specs
 
learn about construction details of PCB layout, op amp bypass, gnd planes/power routing (or lack of quality of same) which can rule out many fast op amps being stable when rolled into layouts that work for order of magnitude slower chips
 
 
hopefully my pointing this out every few thousand posts, in response to new participants, isn't going to derail the thread
 
Aug 11, 2014 at 2:16 AM Post #4,704 of 7,383
So I was looking for an op amp that would almost be an opposite to the LME49990 - not opposite as in "it'd sound crappy" ,but like where "cold and analytical" is the opposite of "warm and embracing". 
 
For reference I plan on using said op amp on a Xonar DS; it's stock op amp was a NE5532P and I replaced with an LME49990 (2x on a DIP8 that is).  Also, I don't want anything like the NE5532P. :p  It just seemed particularly unnatural-sounding to me or something.
 
 
EDIT: Before I got the LME49990 I had read that it's like turning up the contrast on your TV to maximum.  By comparison, I've found comments that the LT1122 is very smooth, which to me sounds like an candidate for being an opposite of the LME49990.
 
 
 
I also noticed that there's no wiki or database for op amps or anything as far as I can tell.  For there being something like this huge thread here, I'm surprised there's nothing that has a lot of the info in a nicely organized manner, such as the generally accepted characteristics of each op amp (slow/fast, wide/narrow, warm/cold, etc).
 
Aug 11, 2014 at 4:05 PM Post #4,709 of 7,383
I would prefer not to.  I probably could if I really wanted to considering I've done crazy things like removing the IHS from a CPU with a razor blade (done it on 4 CPUs and all were a success).
 
Also my father soldered all the time in his youth and even does some today still, so I'm not particularly unfamiliar with it.
 

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