General consensus of opamp sonic signatures?
Feb 28, 2006 at 12:17 AM Thread Starter Post #1 of 18

RnB180

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I know synergy and the amps play a role,
but im just seeking some opinion about two specific opamps and thier sonic signature

OPA2134
and
opa627

can some of you give me a run down of the sonic characteristics of these opamps in an amplifier, both would be running in Class A.

In your opinion which is preferred?
 
Feb 28, 2006 at 12:23 AM Post #2 of 18

ericj

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You're comparing a $2.60 dual opamp with an $18.38 single opamp?

It should also be noted that the 'sonic signature' of an opamp matters a lot less when the output is buffered, and further that the buffer itself will add it's own 'sonic signature' - buf634 will be different from HA3-5002, and different from el2001, and different from discrete buffers, and the discretes used in those buffers will have an effect as well.

You don't see a lot of class-A cmoys, so, your question doesn't ask enough.
 
Feb 28, 2006 at 1:53 AM Post #3 of 18

The Monkey

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Quote:

Originally Posted by ericj
You're comparing a $2.60 dual opamp with an $18.38 single opamp?


Why not? Tangent does just that.

rnb, I haven't heard the 627, but I've agreed with Tangent's take on just about every opamp, so I think you should start there.

I guess OT, but one thing that surprised me recently is how much I like the 8610/20 combo as opposed to the 2132, 2134, and 2227 in my Pimeta regardless of the phones I am using.

And ericj is right, some more details about the amp will be helpful.
 
Feb 28, 2006 at 2:30 AM Post #4 of 18

fewtch

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Quote:

Originally Posted by RnB180
opa627


Very detailed, somewhat laid back, somewhat dark, smooth (perhaps overly smooth) midrange. Good balance of the frequency ranges. Seems to have the potential to sound muddy with some recordings, and/or dead with some headphones.

Just generalizations though, the sound of opamps varies a lot depending on the rest of the circuit.
 
Feb 28, 2006 at 2:55 AM Post #5 of 18

RnB180

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thanks for the opinion and link guys.

Nope this isnt for a cmoy, Im just trying to have a good idea what opamp would probably be more appealing to listen to in commercial amps.

More thoughts would be apprecaited. General thoughts are perrfectly fine. I know its not set in stone. But a general idea is all I seek.

Cheers
 
Feb 28, 2006 at 2:55 AM Post #6 of 18

mrdon

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Quote:

Originally Posted by fewtch
Very detailed, somewhat laid back, somewhat dark, smooth (perhaps overly smooth) midrange. Good balance of the frequency ranges. Seems to have the potential to sound muddy with some recordings, and/or dead with some headphones.

Just generalizations though, the sound of opamps varies a lot depending on the rest of the circuit.



I wouldn't call the opa627 very detailed, but it does have a very good soundstage. I would recommend it with Grado's but not Senn's. Just my opinion.
 
Feb 28, 2006 at 3:00 AM Post #7 of 18

Xakepa

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Gosh, that's what everybody is saying. TI chips and Senn 580/600/650 don't seem to fit.

I like 2132/2134 as an "everyday" chip - it's extended in the highs, have a nice midrange, and as most of the consumer cans have enough bass, fit's em pretty well. 2132 CMoy sounds great with PortaPro, better than any other chip I tried.
 
Feb 28, 2006 at 3:02 AM Post #8 of 18

RnB180

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This is just what Ive experienced.

I modded the onix xcd-99 with some opa627s, and the portable amp I tested it with was the micro amp. The micro amp is generally a really warm amp. it pairs well with my micro dac which is analyitical. but when I paired it with my modded cd player, the sound gets really slugglish and muddy souding. Its a bit more natural than the stock onix, which was sterile and thin. But it seems that the onix stock prior to the opa627 upggrade was more synergetic then the opa627 upgrade.

I lose the upper most detail and refinement after the modification. I was using sennheisers BTW. I had to turn off crossfeed on the micro amp because the combo with the 627s in the cd player just made it too bassy. and the detail diminished. However out of my laptop the micro stack sounds very balanced.
 
Feb 28, 2006 at 3:04 AM Post #9 of 18

RnB180

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Quote:

Originally Posted by mrdon
I wouldn't call the opa627 very detailed, but it does have a very good soundstage. I would recommend it with Grado's but not Senn's. Just my opinion.



why is that?
 
Feb 28, 2006 at 3:56 AM Post #10 of 18

saturnine

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Quote:

Originally Posted by mrdon
I wouldn't call the opa627 very detailed, but it does have a very good soundstage. I would recommend it with Grado's but not Senn's. Just my opinion.


(Opinons based on use with a PPA & a friend's heavily modded PIMETA)
I agree with the Grado synergy, but the 627 is definately detailed in it's own little way. Some other popular faster opamps seem to shout out details in the highs & upper mids (AD8610 IMO) but the 627 remains detailed in every spectrum without sounding bright with certain recordings/headphones. IIRC Headroom uses the 627 in the Max line. That says something.

Dunno about the 2134 though. Gotta try one sometime
smily_headphones1.gif
 
Feb 28, 2006 at 4:07 AM Post #11 of 18

Teerawit

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Quote:

Originally Posted by mrdon
I wouldn't call the opa627 very detailed, but it does have a very good soundstage. I would recommend it with Grado's but not Senn's. Just my opinion.


Well...IMO I like the OPA627 with Senns for the wide soundstage. I like to have a wide soundstage with the Senns....better to open it up and emphasize the positives than narrow it IMO. The OPA627 sounds pretty good with Grados too. This is with a headphone amp though....dunno what type of circuitry it's amping in the Onix.
 
Feb 28, 2006 at 4:12 AM Post #12 of 18

jl123

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I just built my ppa to run my 650s a few days ago using opa627s and at first I felt it was too laid back. I was using some sr60s on a cmoy running a 2132 before. Anyways, I'm starting to like the sound im getting from the 627s and I do believe the detail is still there but it's not as bright(harsh to my ears). I think you just have to listen carefully and enjoy the smoothness.
biggrin.gif


I'll give the hd650s a shot with the cmoy....heh.
 
Mar 1, 2006 at 5:59 PM Post #14 of 18

NeilR

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RNB,

I don't consider myself a "golden ears" guy, but I have built a few amps and have a few sets of the OPA627 and AD86x0's to compare, plus OPA2134 and some others. I think this might be a good analogy...

When you hear a close miked cymbol crash, if you like to hear it buttery smooth, you will like opa627. If you like an edge to it, you will like AD86x0 better.

That's one of the easiest differences I have noted that I can articulate and I think this carries down into lower frequencies to some greater or lesser extent. I suspect that OPA627 has better bass impact. Not overall bass, but that slam that should happen when it should happen. I don't like boomy bass but I like my head shaken side to side when the music wants that to happen.

BTW, I use Senn 650's for most of my listening.

It's like asking someone if they like vanilla or chocolate better; I think it is a matter of taste.

It is interesting that, frequency response-wize, these chips are all flat from DC to the speed of light, at least as far as the human hearing range is concerned. Same with the other major specs like distortion. There is none on any of them, for all practical purposes.

There is one measurable difference, though, and that is power consumption. OPA627 consumes 7-8 ma per channel and AD86x0 consumes about 2.5-3ma. For that reason, I favor the AD86x0 in my portable Pimeta, which has 3 channels plus 3 buffers. It's a lot easier to feed the beast. I think I am going to keep OPA627 in my desktop amps and use AD86x0 for my portables and then I get a little change of pace, soundwize and I can optimize the battery consumption. I know you understand battery consumption because you have the Micro
k1000smile.gif
 
Mar 1, 2006 at 6:05 PM Post #15 of 18

NeilR

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Quote:

Originally Posted by The Monkey
Why not? Tangent does just that.

rnb, I haven't heard the 627, but I've agreed with Tangent's take on just about every opamp, so I think you should start there.

I guess OT, but one thing that surprised me recently is how much I like the 8610/20 combo as opposed to the 2132, 2134, and 2227 in my Pimeta regardless of the phones I am using.

And ericj is right, some more details about the amp will be helpful.



Monkey,

As I understand Tangent's description of his test amp, he buffers the virtual ground, but not the right and left channels. It makes sense in the context that he is using it for. I think you interpreted it as he is using a buffered amp such as a Mint or Pimeta. I could be wrong, though; just my interpretation.
 

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