[windrider]

you can get "free" lt opamp samples so thats a definite must imo.

lme49720s samples are "free" too except for the shipping i think.

opa627s have to be bought; IMO its a worthy buy but doesn't hurt to try out the others first.

to me they sound MUCH better than the stock opamps; the sound was much smoother/less grainy with any of the above compared to stock.

 

[koppite]

OK! Just dropped $300 on the upgrades! Now it's time to wait!!

(He's not ripping me off, right? That's the normal price?)

 

[ciphercomplete]

What on earth did you get? Or was it $300 total for the DAC and the opamp upgrades?

 

[koppite]

300 Total.

So it seems like the Van Den Hul Optocupler is going to be the best way to go. Is there a difference between using this out of my macbook and using the PCLink?

 

[alfo]

I ordered the zero from Lawrence a few days ago together with the opa 627. I'm replacing my headroom microamp that fried.
As my senn 650 collect dust, I'm killing the wait time by reading this thread: page 176, 200+ to go and by the time I get here there will be more, so keep writing

 

[AudioPhewl]

I've received my Zero DAC today. It's a good-sounding little box, it really is. Swapped all the opamps out for OPA2134, which are about the nicest 'sounding' dual opamps I have sitting around right now.

I've always been a fan of the LT1028 single opamps - they sound incredibly clear, and the most 'natural' sounding opamp I've heard - but I'm very out-of-touch with opamps these days - have tried the OPA627, which I felt was a little "wooly" sounding - I guess I'm not so keen on the 'warm' sound most people aspire to

.

I've seen the list of opamps on the first page, with comments like "Good" and "Great", but that doesn't really answer my query - what opamps should I be looking for, to find a sound like the LT1028? Should I order 6 fresh LT1028s and adapter boards? I don't really want to, because they specify a maximum of 24v, but this little box puts out a total of 30v to the opamps... I guess that's why an earlier post comments on how hot they run!

Also... it may be covered here already(388 pages... this should be broken up into a "review" thread with opinions, and another for mods and opamp discussion) , but are there any easy mods? In the past, I've always replaced the coupling caps for little polyester caps. Is it worth me removing the boards from the DAC and tracing the audio signal, or are they already polyester? There are a lot of little square caps in there already...!!

Thanks!

Phewl

 

[ianp]

Hee. I just ordered a second unit. The first is now seeing full-time service hooked up to my tube amp, replacing a monica DAC. The second will be a headphone amp ... I promise.

 

[Currawong]

Quote:

Originally Posted by koppite /img/forum/go_quote.gif 300 Total. So it seems like the Van Den Hul Optocupler is going to be the best way to go. Is there a difference between using this out of my macbook and using the PCLink?

What do you mean by "PCLink"? Make sure you're getting the Toslink to Mini Optical version of the Optocoupler for your MacBook. The Toslink end will go into the ZERO and the Mini Optical goes into your headphone socket.

 

[StratCat]

@AudioPhewl + ianp:

May I ask which vendor you ordered your Zero from, and how long it took for final delivery?

I just ordered an un-modded unit earlier during this week from Lawrence, but now that I've finished reading this entire thread, I was wondering if I might've been gotten a faster turn-around time (and saved a few bux) by going thru "wsz0304" from the Shenzhen Audio ebay store?

Edit: You may PM me, at your descretion, if you prefer to keep vendor discussion private, or out of the main technical thread

 

[Penchum]

Quote:

Originally Posted by AudioPhewl /img/forum/go_quote.gif I've received my Zero DAC today. It's a good-sounding little box, it really is. Swapped all the opamps out for OPA2134, which are about the nicest 'sounding' dual opamps I have sitting around right now. I've always been a fan of the LT1028 single opamps - they sound incredibly clear, and the most 'natural' sounding opamp I've heard - but I'm very out-of-touch with opamps these days - have tried the OPA627, which I felt was a little "wooly" sounding - I guess I'm not so keen on the 'warm' sound most people aspire to . I've seen the list of opamps on the first page, with comments like "Good" and "Great", but that doesn't really answer my query - what opamps should I be looking for, to find a sound like the LT1028? Should I order 6 fresh LT1028s and adapter boards? I don't really want to, because they specify a maximum of 24v, but this little box puts out a total of 30v to the opamps... I guess that's why an earlier post comments on how hot they run! Also... it may be covered here already(388 pages... this should be broken up into a "review" thread with opinions, and another for mods and opamp discussion) , but are there any easy mods? In the past, I've always replaced the coupling caps for little polyester caps. Is it worth me removing the boards from the DAC and tracing the audio signal, or are they already polyester? There are a lot of little square caps in there already...!! Thanks! Phewl

Beware of ANDREA. If anyone with less than 25 posts starts telling you about the wonders of their Opamps, it is ANDREA under an assumed name. Just ignore him until the moderators can delete him and delete his posts.

This thread grew at an enormous rate and was way too big to separate by the time we realized there might be real benefits to it. So, we just keep plugging away.

 

[Navyblue]

Why don't you start a review thread on how good is your Super Pro 707 and include a comparison on how crappy is the Zero?

Btw, I pity people who have no have no life or self-respect.

 

[Navyblue]

Quote:

Originally Posted by jmooo /img/forum/go_quote.gif I'm not surprised that people like you jump on the bandwagon of this thread and look no further.

Unfortunately your assertions are incorrect.

First, I have yet to jump in the bandwagon.

Second, I am still looking around.

In fact I have no idea if Zero is a good DAC. But I could tell a mature individual if I see one.

 

[AudioPhewl]

Quote:

Originally Posted by jmooo /img/forum/go_quote.gif It does work perfectly with supplies of +/-15V, read the datasheet carefully!

My apologies, I was going from memory. Could have sworn it was rated at +/-12v - I was so certain that I'd read this, I dropped the voltage feeding them in my diy headphone amp to +/-12v rather than +/-15v.

Damnit, they sounded really sweet at 15v too. All this time my ears have been crippled for no good reason!

Quote:

Similar sounding opamps? The LT1358 is similar enough, and works perfectly in the DAC board. The THS4031 (dual is THS4032) is rather similar (and very good) too.

Both sound similar to the LT1028. My recollection is that THS4032 appeared to give more detail on first impressions, but continued-listening revealed some 'wrong' sounds. It was a while ago, and I can't really put my finger on it...

Quote:

Originally Posted by StratCat /img/forum/go_quote.gif @AudioPhewl + ianp: May I ask which vendor you ordered your Zero from, and how long it took for final delivery?

I'm in the UK, and I dealt with a lady in China who goes by the username 'snow48_6'. Took ~15 days to be delivered, but I think she sat on the order for the first 3/4 days going by her recent feedback - people who ordered 3 days after me received it on the same day.

Quote:

Originally Posted by jmooo /img/forum/go_quote.gif How do you find the OPA2134 to sound, compared to the stock OPA2604? Recently I tested the OPA2132 in an amp, and I found it to sound much better (there) than a much harder sounding LT1364. The LT1358, however, is better than both (there).

IMO, there is a difference, but it isn't huge. It's comparable to the difference between any other 2 good audio opamps. Biggest difference IMO is the midrange has stronger presentation, and the sound has a bigger feel to it.

My comments aren't particularly strong, I powered the Zero up and loved the sound. Whipped the lid off after a couple of hours use and swapped the opamps back and forth a few times - there was a difference, but I didn't use the OPA2604 long enough to give a detailed comparison.

Bloody IC sockets are a really tight fit on the legs of the IC. They have to be perfectly matched, or they'll bend over themselves very easily.

Quote:

Originally Posted by Penchum /img/forum/go_quote.gif Beware of ANDREA. If anyone with less than 25 posts starts telling you about the wonders of their Opamps, it is ANDREA under an assumed name. Just ignore him until the moderators can delete him and delete his posts.

Who, or what, is Andrea? Someone trying to plug their product?

Anyway, back on topic. I may just order some more LT1028s. I'll have to price up 6 of them(!), as well as the single-to-dual adapter boards.

~Phewl

 

[AudioPhewl]

Just to add that I've bypassed the 4xElna caps on the DAC board, and the 2 on the amplifier board. DC offset remains at 0.002v, which is the same as it was before bypassing.

Difficult to describe the difference. If going from the OPA2604 to an OPA2134 yielded a 5% improvement(which is probably fairly accurate IMO), then bypassing these capacitors yields in excess of a 10% improvement. It's like opening a clean, translucent window - everything is the same, but you get the smell of outdoors as well...

One thing to note is that my DAC board didn't have the red Elna caps in the below pic, it had black and gold ones(ES?). The headphone amplifier had a pair of red ones, as per the below picture.



~Phewl

 

[AudioPhewl]

Quote:

Originally Posted by ko! /img/forum/go_quote.gif Please try those LT1028 and tell us! I'll be just a silent reading presence from now on...

I'd love to, but I don't have any adapter s-to-d boards. I could construct one myself, but I don't have any of the "turned pin" edge connectors, just the pressed metal ones. They'll not fit the sockets fitted inside the DAC.

Plus, money isn't free-flowing at the moment. 3x adapter boards and 6x opamps soon add up, especially with shipping. We're in the middle of a "credit crunch" over here in Britland

.

~Phewl.