The Opamp thread

[leeperry]

These were LT1363CS8's from the same batch, and I've noticed the same diff. w/ AD797BR...it's always sounded bass shy on those presoldered ebay adapters, but sounds as bassy as can be on a genuine browndog.
 
adapters matter a lot, as this guy's commercial bs tries to prove: http://cgi.ebay.com/10pcs-Dual-SOIC-to-DIP-8-Convert-PCB-Adapter-SMD-OPA627-/230379640581

 

[Mad Max]

I still think you messed up somewhere.

 

[12Bass]

Finally had a chance to listen to the OPA228 and made a comparison with OPA211.  In my application, I'm hearing perhaps a somewhat thinner, though more open, sound than the OPA211.  The OPA211 may have a bit more fullness in the lows, while the upper-midrange/treble region is more aggressive as well.  OPA228 might sound less "effected".  Still not sure which I prefer.  Both are decent chips, IMO.

 

[12Bass]

Also did another comparison between OPA211 and OPA1611.  Their specifications are extremely close, so much so that it appears that the OPA1611 may just be a rebadged OPA211 which is marketed for audio applications.  However, after several A/Bs, there was a noticeable difference between the two.  Although their basic tonalities are very similar, the OPA1611 just doesn't seem to have the same clarity as the OPA211... sort of more "bland" sounding.
 
Did a little more listening to the OPA827 during the same session.  I get the impression that it has a bit more coloration than the bipolars, though it is a euphonious coloration, IMO.  It seems sound fat in the bass, pleasing in the midrange, and smooth in the highs, without the "edge" of some other parts.  It is pretty detailed for a FET device, but appears to lose a little resolution compared to the better bipolar op amps.

 

[leeperry]

I still think you messed up somewhere.

Well, goodie for you

 
I use cardas eutectic solder and a 30W sharp iron, I've never burned a single chip. OTOH, LT1028CS8 and ACN8 sounded *way* different for me on browndogs, Andrea told me they didn't for him.
 
One thing I know is that AD797BR and LT1363CS8 sound bass shy for me on non-genuine browndogs...You said you don't like 1363 but you did put it on a diyinhk adapter, maybe it's about time you start evaluating this chip properly

 
OPA1611 sounded terrible to my ears..just like OPA211/827(and ADA4627-1A for that matter 

)

 

[12Bass]

Quote:

OPA1611 sounded terrible to my ears..just like OPA211/827(and ADA4627-1A for that matter 

)

Mind to say why you think they sound terrible?  To my ears, the OP211 and OPA827 have pretty different tonalities. Will be trying the AD797 again soon to see if my impressions might change. 
 
Haven't tried ADA4627-1.  ADA4898-1 didn't wow me; however, looking at the data sheet, it may take an optimized circuit for it to perform as designed (very low impedance).

 

[leeperry]

OPA211 sounded like something was really going terribly wrong, as majkel said: http://www.head-fi.org/forums/f6/audio-gd-discrete-op-amps-reviewed-OPA-earth-OPA-moon-OPA-sun-v-2-a-397691/

 The increased shape detail and huge soundstage is probably the result of something I'd call sound disassembling. It's like losing spatial coherence of each sound, having the tone in one place, and the harmonics just aside, not surrounding the right tone. Strange but true.
 

 
I really hated listening to this chip...and well, OPA827/ADA4627-1A just don't do it for me...really not the sound I'm looking for, it's hard to explain. ADA4627-1A had some kind of very colored bass and "plasticky" mids, to me all those chips have "BB" written all over them...and that's really not hifi to my ears.

 

[12Bass]

After some consideration, I may agree somewhat with majkel about the OPA211.  Not sure, but it almost seems as if the frequency spectrum is not entirely continuous, as if there's something missing between the midrange and the treble.  In comparison, the OPA827 sounds more "connected", though less "impactful".  I like what it does with my basses.... warm, yet detailed.

 

[SpudHarris]

I'm not actively rolling at present as I seem to have found my perfect match for both my Fi-Quest and my P3+.
 
Fi-Quest is running with metal can OPA637's and 4 x stacked buffers and the P3+ has a metal can OPA2111 with 2 x stacked buffers and OPA627's in G/VG.
 
My new venture is to find my perfect match in Tubes for my new Woo Audio 6  

. I'm monitering this thread for the next best thing in Opamps to appear but until then I'll be lurking and rolling Tubes......

 

[majkel]

I'm curious how much better are the metal can versions than DIPs, especially regarding the OPA2111, OPA627 and OPA637? Even compared to the OPA827AID, the OPA637AP sounds rather poor. I went back to the op amp topic as I modify from time to time Lehmann Black Cube Linear like amps. I had the best results with the OPA2228, the AD8599 being second best. I also found it to be no advantage to have two OPA228 pieces. The soundstage is more dual mono, but imaging is less coherent, with lesser focus. I no more support the offset pin biasing trick as adding some good bipolar and film capacitors between supply rails gives better results without such "cheating". The trick actually sounded a bit fake on the AKG K 701. Grado PS1000 accepted it well, making some advantage of the smearing effect on these edgy headphones.

 

[SpudHarris]

To my ears the OPA2111AM was a lot nicer all round than the KP version. With the OPA637AM's I'd like to say they were a million times better than the BP's but to be truthful I think they only just better them and even that could be placebo because they ARE ''Metal Can'' and have ''Gold Pins'' who knows?
 
My opinions regarding rolling have mellowed recently due to being happy for once with the results I have. Only thing is, I now have loads of tubes on route from all over the world for rolling haha.... 

 

[leeperry]

Last time I tried tubes I quickly got to understand why opamps superseded them, hah

 

I like what it does with my basses.... warm, yet detailed.

 
tried LT1028ACN8/LT1363CS8/AD797B? their bass is top-notch, 1028's bass is louder/more flabby IME, 797B's a bit too analytical but 1363CS8's is the perfect in-between...I'm so glad that my opampitis is finally cured(for now heh), and 1363 needs a clean PSU due to its lowish PSRR. BB can only dream about reaching the SQ of the 3 aforementioned chips...the PCM1794 datasheet advises to use LT1028 as LPF for a good reason.

 

[Apocalypsee]

LT1364 is a great opamp, it work virtually anywhere, and sound great anywhere as well. Tried it on old SB Live! 5.1 soundcard, it sound excellent. Tried on X-Fi Elite Pro, sounds awesome as well. Used it on X-Fi Surround 5.1 USB which use only single 5V supply, LM4562 sounds terrible with lots of sibilance and harsh treble but LT1364 just shine

 

[leeperry]

Ditto! and 1364 is only slightly worse than 2*1363 on a browndog...some commercial DAC's run it stock: http://www.google.com/search?hl=en&q=poppulse+lt1364c
 
It must be quite a shock for non-rollers to have such a good sounding chip in a commercial unit

 
http://www.tnt-audio.com/sorgenti/usb_dac_shootout_e.html

Right from the off, the SuperPro is impressive. Impressive in the amount of fine detail it produces. Its sound is bright and sparkly (but certainly not over so). Detail retrieval is very good and it does that 'layers' thing where you get a very good range of tone. It's musical, and grabs the attention. Sound-stage is large and imaging very clear.

 

[Spacehead]

Quote:

LT1364 is a great opamp, it work virtually anywhere, and sound great anywhere as well. Tried it on old SB Live! 5.1 soundcard, it sound excellent. Tried on X-Fi Elite Pro, sounds awesome as well. Used it on X-Fi Surround 5.1 USB which use only single 5V supply, LM4562 sounds terrible with lots of sibilance and harsh treble but LT1364 just shine

Nice! I have LT1364 also on my Sound Blaster X-FI. It is excellent, clean, accurate, musical op amp!