The Opamp thread

[leeperry]

I also love when MOT's explain that the 5532 is teh best opamp evar to drive headphones: http://www.head-fi.org/forum/thread/223006/benchmark-dac1-now-available-with-usb/2940#post_6809841
 
together w/ those 4562(presumably used as DAC filters) = killer combo!
 
in that shootout, the DAC1 was said to be so-so: http://ravenda.wordpress.com/2009/08/14/audiogddac19/

 

[Mad Max]

Quote:

I had opa2111kp for treble and opa2107ap for bass soldered in my amp, I found that it is lacking of low mid(whispering is barely audible in movie).

What opamp shall I change for my xonar essence stx to gain the low mid for easy listening with wider soundstage, clearer and warmer sound?
I have opa2132pa, opa2111kp, opa2107ap, opa2277pa, opa228pa, lt1028, lt1363 and lt1364 here.

Why don't you try something more balanced-sounding?  Can you solder?
 
 
ADA4841-1 has the widest soundstage I've heard, as well as OPA1611.  4841 is kind of natural-sounding as far as soundstage, a pinch warm, too.  I can't remember the others right now.  I keep forgetting to check opamps' soundstages with RE-252, its soundstage is the most sensitive in my arsenal.
You could also try AD8065/8066 or AD744/746.  If you decide on AD744, I recommend you shoot for the ceramic dip version (744KN) or the metal can version (744AH) if possible.

 

[Mad Max]

Oh man, I'm liking the FiiO E5 again.  With 4841-2 the soundstage is more natural and overall the sound is more detailed, cleaner, clearer, and slightly tighter. It still can't lay finger on my Minibox-E+, but for the twenty bucks it sells for, this thing is real nice with an opamp change.

 

[ecclesand]

 
Quote:

 
The OPA1611,1612, were well liked by many around here.  I noticed you tried some of the THS series, have you had a chance to test out the THS4032 or the singles THS4031.  It seems many people recommend these for I/V section for DAC's.  They can be rather unstable if used improperly.
Have you done any further testing with the mentioned units?
 

I just ordered a couple of the THS4031 and some .01uF PPS caps to solder across the rails for stability.  I plan to use them in the I/V stage of an Assemblage DAC I just picked up.  I too heard they were great for this very purpose.

 

[cent]

Quote:

Why don't you try something more balanced-sounding?  Can you solder?
 
 
ADA4841-1 has the widest soundstage I've heard, as well as OPA1611.  4841 is kind of natural-sounding as far as soundstage, a pinch warm, too.  I can't remember the others right now.  I keep forgetting to check opamps' soundstages with RE-252, its soundstage is the most sensitive in my arsenal.
You could also try AD8065/8066 or AD744/746.  If you decide on AD744, I recommend you shoot for the ceramic dip version (744KN) or the metal can version (744AH) if possible.

 
Yes, I can solder but the onboard tracing for the DIP-8 is worn so not dare to desolder it again.
Actually the opa2111kp is the replacement for my stock st4558, I'm afraid that circuit cannot support any higher speed opamp.
Now searching for the opamp for I/V and buffer on soundcard to pair with my amp to get the sound I desired for.
 

 

[cent]

Yes, I can solder but the onboard tracing for DIP-8 is worn so I not dare to desolder it anymore.
 
Actually the opa2111kp for my amp's treble is a replacement for the stock st4558, I'm afraid it won't be stable changing to higher speed opamp.
 
So the best I can do now is try to change the I/V and buffer opamp in my sound card xonar essences STX to pair with my amp and get the sound I desired for.

 

[ROBSCIX]

Quote:

 

I just ordered a couple of the THS4031 and some .01uF PPS caps to solder across the rails for stability.  I plan to use them in the I/V stage of an Assemblage DAC I just picked up.  I too heard they were great for this very purpose.

Let me know what you think when you get them soldered up and tested.  I always keep a few dual THS4031 and THS4032 modules around for testing.

 

[ecclesand]

Hmmmm....gave them about 48 hours and they sound OK in the I/V stage of the Assemblage DAC.  I pulled them and dropped in a pair of OPA827.  To my ears, the OPA827 sounds much better than the THS4031.  At least the THS and the caps were cheap.

 

[genclaymore]

You guys know any netual op-amp to be used with my AKG 702s which are coming tommow? I knoww about the earth,but something as a pdip til I get around to getting a OPA-earth.

 

[gwillys]

need some advice. i've found that my aune/hifidiy mini usb dac sounds best with no opamps. i only use rca out, so i'm pretty sure only the opa2604 is in play here.
 
without opa's, the volume control on my ext. amp makes static only when it's turned. and when switched off, the dac's power led stays lit, but fainter. so i measured across ground, and there's 8v. probably not a good thing, but the equipment shows no stress.
 
besides slightly reduced volume output, which is of no consequence, it sounds great.
 
i'm wondering if anyone can help a novice rectify this. i was thinking maybe some type of jumper/resistor/cap across opa socket, but i don't know enough to attempt that. i did put a cap between pins 4 & 8, but no change.
 

 

[Yoga Flame]

I'm guessing you removed the opamp in the DAC position, and left the OPA2604 in the amp position. I tried removing the DAC opamp too, but I wouldn't say that it sounds best that way. FWIR the opamp in that position is used as a low pass filter. So there might be some high frequency noise without the filter being used (at least that's how I understand it).
 
I think OPA2604 might be the bottleneck for you. In my experience that did not work very well in the Aune compared with the other opamps that I tried.
 
I don't really have an answer to your question. But I think you are looking for a "dummy op-amp". I recall reading something about that from Dr. Xin. It was pretty much just a couple of jumpers in a DIP-8 socket, if I remember correctly.
 
 
(Just so everyone is clear, the Aune will still work without the DAC opamp in place, only with lower volume and maybe a little more noise. edit: The headphone out will not work at all without the output opamp in place. But the line out will work.)

 

[gwillys]

thanks, but for line out, which is the only way i use it, it works without both opamps. yes, maybe a dummy opamp would work, i'll see what i can find on dr xin.

 

[Yoga Flame]

Ah, okay. Thanks for the correction. I had not tried the line out that way before. Edited my post to fix the inaccuracy.

 

[leeperry]

You might like this thread: http://www.head-fi.org/forum/thread/270984/best-op-amp-for-x-fi-prelude-meridian-or-socketed-soundcard-if-using-an-amp-is-none#post_3450796
 
On the Prodigy HD2 there's 3 dual opamps: 2 used as AK4396 LPF and one bringing them to line-out level. I could remove the latter, but then the sound was thin/bass-shy and dull.
 
From now on, I want to have as little opamps as possible in the signal path, two single opamps used as DAC LPF > done. PCM1793 does just that and sounds awesome.

 

[gwillys]

audiogd dac-19 has no opamp in signal path. probably the way i'll go.
 
the aune/hifidiy mini dac sounds pretty darn good with the opa's yanked out. with a better psu & mods like super regulators, burson clock, recap with silmic II it would be really nice. though expensive and not very practical. i'm getting tired of all this modding. there is so much marketing hype with all this stuff, it gets expensive trying to sort it all out. one thing i'm certain of at this point, for a dac, no opamp is the way to go. cost me alot of money and time to discover that.