Review: ZERO 24 BIT/192KHz DAC/Headphone Amp/Pre-Amp

[fault151]

Originally Posted by Normality

I do surely hope it sounds better than the (basic version) CD6000 I had, because I didn't like it at all - so much better is my Cambridge Audio D300SE, even if I've tweaked it. If it sounds better than the tweaked Cambridge Audio (& it has a very good integrated headphone amp, which I need), I will be in heaven

Let's hope so ey! The reason i asked is my friend wants me to bring it round an listen to it and compare it to his set up he already has. In particular the cd players internal dac.

Oh is there anything else we can easily upgrade on the zero dac or would you say it's about as much you can do changing op amps?

Cheers

[fault151]

Originally Posted by Normality

For what I understand looking at the various pics (since mine momentarily is still as the postman delivered it ) everything looks pretty well optimised as it is - especially the electrolytic caps look good both in size & quality; save, if you will, for those two dark-green caps near the opamp socket. Those could be worth changing for something with polystyrene of mica dielectric.

Even my Cambridge Audio uses a couple of polystyrene caps in the same position in its output stage. However, I'd first want to hear how good the Zero sounds "as is" to decide if this could be worth the risk & the hassle or not.

So has yours just arrived then today?

[fault151]

Originally Posted by Normality

So...these are the LT chips one can safely use in the DAC:

LT1469 (or two LT1468), LT1364 (or two LT1363), LT1361 (or two LT1360), LT1057, LT1358.


I'm still puzzled at the LT1361 not behaving as expected in the DAC, according to Penchum. I'm really inclined to try it anyway, since I've always loved it, & sometimes thought it was better than the LT1364 due to having slightly more body as fault151 said?

I put it in the headphone section with my 627 in the dac. Out of all the op amps i have, it was between the 1361 and the 1364 as the best sound in my opinion. I went with the 1361.

[fault151]

Originally Posted by Normality

No it's almost a week that it's been waiting upon a shelf, still packed. Sorry. As I said before, I hope I manage to try it by the weekend.

Oh rite. i couldn't resist opening it and having a listen, even just to get it burned in a bit. I think this was because at one point i didn't think it would arrive so when it did i thought right this thing best be worth the fuss!

[fault151]

Originally Posted by Normality

Did you perceive a lack of treble detail with the LT1361 in the amp, as compared to the LT1364? I don't remember this personally.

Btw have you tried the LT1469 too?

No not really. I was listening to Marcus Miller playing slap bass so it probably wasn't the best test for treble. His bass would make even the most mellow sounding op amp sound bright. I really like the sound of the 1364 and i think personally it's pretty close between the two.

[fault151]

Originally Posted by Normality

Btw, I think it was you who asked about a coaxial digital cable before?


I have ordered one with BNC-RCA connectors using the Belden 1694 cable on Blue Jeans Cable UK--Quality Cables at Reasonable Prices

cheers, how much did it come to?

[fault151]

Originally Posted by Normality

£12.70 (0,5m long)

Thats not too bad then, cheers.

[fault151]

Originally Posted by Normality

Also,

I have just ordered from National two LME49710 and two LME49720, all in the TO99 "metal can" package.

I have sockets to solder the duals to, and twin-DIP Browndog adapters to solder the singles on. Looks promising

Ok now I'm done with opamp samples, both free and at charge

Can you point out to me how you distinguish between what is a dual amp or single amp by looking on the net? Is there a clue in the title or does it simply just say it next to the description. I have only tested recommended op amps by member on here for the zero.

Cheers.

[Penchum]

Originally Posted by Normality

But, you did say that the LT1364 was the clear winner for the DAC position.

I think that the LT1364 has better midrange tonality and better bass articulation than the OPA627, whereas the OPA is a little bit thicker (which I like). I'd want to have the two combined into one!

Maybe the OPA827...

And now I want to try the AD797 as well.

Yes, I said that. Look at the chart. It worked great in the DAC with many others in the headboard. It was the surprise I wasn't expecting. My note could have been addressing the 627 in DAC working with the Super-T or 627 in DAC above all others. So, if you have the 627's, give 'em a spin and see how it sounds with your rig. It might be surprising! Ow, and you are going to not like the AD797s in the DAC. It does the weirdest thing to highs I've ever heard. I can't even describe it. Hey, I thought you said the DY2000 would be the sweet spot in the DAC?

[Penchum]

Originally Posted by Normality

Unfortunally mine haven't arrived (not even this morning) and I'm starting to despair.

So I have those LME's on order, just in case


DY2000 + LT1469 or LME49720 may well be a sweet spot, indeed. Also LT1469 or LME49720 + DY2000, though.

Ow, so you think they'll respond well swapped too. Hummm. Do you still have your 627's?

[Penchum]

Originally Posted by Normality

This, together with the warming up of the chips, might be a sign that they're oscillating.

Damn, that might be it. Like an uncontrolled oscillation, moving faster, then slower depending on the notes being played. It was almost spooky. It didn't take me but a few seconds to power down and pull 'em.

[Penchum]

Originally Posted by Normality

Sure; I guess I'll have to get them ready for use, soldered on a browndog (I have four of them and as many as 8 twin-DIP browndogs, so).


The LT1469 should be a clearer sounding opamp than the DY2000, but possibly with less 'character'. So it depends on what you want in the line out.

When you get yours out of the box, you should try the 627s in the DAC and the 1469s in the headboard. This may be the "middle ground" for the headamp, but warmer, smoother in the DAC. My preference for this situation was the 1364s in the headboard, but all three: 1361,1364,1469 all sounded nice with the 627s in the DAC.

[fault151]

Originally Posted by Penchum

My preference for this situation was the 1364s in the headboard, but all three: 1361,1364,1469 all sounded nice with the 627s in the DAC.

I agree with that too!

[Penchum]

Originally Posted by fault151

I agree with that too!

The true test of the OPA627s in the DAC for me, will be to hook up the Zero to my Pioneer SPEC1 pre-amp and give her a listen. I'm really hoping it will not be too much warmth. Those high-end solid state goods from the late 70s had a great sound signature and I'm hoping I don't have to go with a brighter Opamp when feeding them.

[mapstec]

Penchum,

since this is your thread, can you edit your first post and include your list from page #100 and also include the warning that the non-unity gain stable opamps can not be used in the DAC section (LT1028, LT1115, AD797)?

That would make things a lot easier on first time readers.

Thanks

btw: Opa627x2 on adapter in DAC and LM4562 is a very, very nice combination!