OPA827, is it sonically comparable to OPA627?

[mudihan]

I searched but couldn't find a detailed review of OPA827. How good is it sonically? I like the sound of OPA627, but it's quite expensive. If OPA827 is as good as OPA627, I will be very happy!

[TheSeekerr]

I haven't heard OPA627, so I can't give a definitive answer, but I'm using OPA827 biased into class A in a (BUF634 buffered) headphone amp right at this very moment, and I can say with certainty that it sounds better than OPA2132, OPA2227 or OPA2107.

The qualities of this chip are exactly as I've heard described for OPA627 - very well controlled bass, with no treble harshness, resulting in a clean, dark sound.

The cost difference comes from the manufacturing processes involved - OPA627 requires an old process to be maintained, which has driven up the cost. At least, that's my understanding.

[SamL]

You know where to get opa827?
Digikey is out of stock. MCM and Allied don't carry them.

[TheSeekerr]

The business I work for ordered some samples to compare with OPA227 for our stage mixers, as we're considering introducing a "premium" model.

There's nothing except your own conscience to stop you from ordering a few samples from TI yourself, of course, but that could be considered abuse, since they cop the loss on the shipping on the expectation that you'll order a few thousand later.

[mudihan]

Thanks for the reply.

The character that I like the most about OPA627 is it's cleanness, which separates the op-amp from the rest (such as OPA2107, which is IMO the second best from TI). That cleanness is in a league of its own! I just wonder if OPA827 would have that character.

[TheSeekerr]

Or rather, lack of character! I think OPA827 does deliver that. BUF634 adds some of the Burr-Brown character to the sound, but with 827, the sound is drier than with other Burr-Brown opamps, so I don't think that 827 adds much character of its own.

[lineup]

The mentioned OPA2107 (dual bifet) was new to me.
Looks like a nice op-amp for High-Performance Audio Circuitry

Comes in DIP-8 and SO-8.
Unity gain stable, +-5 to +-18V and like 4.5 mA supply current (<2.5mA per amp).
The precision, offset, is very good. Very low bias current.
Slewrate is good 18V/uS and gain bandwidth is moderate 4.5 MHz.
Such a bandwidth is, in my opinion, suitable for many general audio applications.

What is the cost for OPA2107, in compare to other op-amps?
If is a fairly low price,
this is a good one to become a universal op for the DIY Audio toolbox.

OPA2107 - Texas Datasheet

Regards Lineup

[TheSeekerr]

OPA2107 is one of those funny chips that is sometimes unobtanium. It is, however, a very good dual opamp for the price (digikey list them at $12.50). Generally, whenever I build something that needs a dual opamp, it's prototyped with OPA2132 to see if it works, and then, provided it can be given at least +/- 7V rails, swap OPA2107 in for the improved sound.

To put some opamps on a scale:

TL072: 50%. Functional, but not particularly pleasant to listen to.
OPA2132: 85%. Great value for money, but bass is indistinct.
OPA2227: 90%. Better than 2132, but poor value, as it's about the same cost as 2107.
OPA2107: 95%. A worthwhile improvement on 2132.
2 x OPA827: 100%. The best opamp I've yet tried - I suspect that for nearly every application, these will be limited only by other parts of the signal chain.

[lineup]

I see digikey lists OPA2107 €10.65 per unit.
If you buy 25 units, you get them for €9.60 per unit.

[hdmi]

Originally posted by mudihan
I searched but couldn't find a detailed review of OPA827. How good is it sonically? I like the sound of OPA627, but it's quite expensive. If OPA827 is as good as OPA627, I will be very happy!

I have this OPA627BM ,divides the US and Taiwan manufacture .is interested to be possible to give you the photo...