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

[vvanrij]

1364 in the amp section don't get 'too hot'. And Henmyr I didn't actually try the 1028

I was more referring to Andrea as the 'crap'

.

 

[Penchum]

Quote:

Originally Posted by ccschua /img/forum/go_quote.gif For the most interesting part, I went to buy 4d(lotto, number forecast or what so ever). I bet 1358, 1469, 4562, and guess what I got the price for that 1469. Sorry digress. I am still burning in the so many opamp that I have. I just wonder how to make the 1028 unity gain stable. This time dont fool around, you almost fry my 1028. Hope to hear the review on HDAM fast. Do you think we can get this HDAM from China rather than Burson.

Lawrence is selling them. Drop him an email for pricing. The big "road block" is still the clearance issue. For me, I must have the Zero buttoned up. Leaving it open is not an option.

 

[Penchum]

Quote:

Originally Posted by vvanrij /img/forum/go_quote.gif 1364 in the amp section don't get 'too hot'. And Henmyr I didn't actually try the 1028 I was more referring to Andrea as the 'crap' .

LMAO! I blew Pepsi on my notebook!

I suppose the 1028's could be a Senn thing, but they were really behaving badly. I ran them over 50 hours and it would not clear up, so I moved on.

Ow, I got my OPA637AU's, so I'm burning them in for a DAC reviewing.

They are stable and work like they should.

More news later on...

 

[fishkill62]

Zero's

Lawrence has sent me my Zero with the Alps volume pot upgrade. I have been having trouble with this pot as it only puts out signal on the right channel when you apply sideways pressure to the pot's shaft.

Lawrence has told me that this could be so as he forgot to solder a ground wire, from the rear pot casing, to the front left plug at the base of the pot.

Can anyone with the Alps upgrade pot please let me know if this wire is on their pot, and the soldering points?

Thanks Chris....getting really frustrated with this....

 

[Penchum]

Quote:

Originally Posted by fishkill62 /img/forum/go_quote.gif Zero's Lawrence has sent me my Zero with the Alps volume pot upgrade. I have been having trouble with this pot as it only puts out signal on the right channel when you apply sideways pressure to the pot's shaft. Lawrence has told me that this could be so as he forgot to solder a ground wire, from the rear pot casing, to the front left plug at the base of the pot. Can anyone with the Alps upgrade pot please let me know if this wire is on their pot, and the soldering points? Thanks Chris....getting really frustrated with this....

I just got done doing my second one, and I don't have any grounding wires soldered to anything. I wonder if you have a "cold" solder joint? If you could heat up and melt the solder on each tab, then test it, the problem might be fixed this way. Compare how yours looks to the pics I posted earlier on.

 

[Pricklely Peete]

Quote:

Originally Posted by Penchum /img/forum/go_quote.gif The outside temperatures here have risen drastically in the last 4 days, so like clock work (and Murphy's law), my A/C system started giving me trouble on Wednesday night. One service call and visit later in the day, and my 20 year old A/C unit was given it's last rights. It seized up and died on Friday morning, just as the A/C crew arrived at the house to install a completely new A/C system. They lent me a portable A/C unit, to keep one room cooler (sort of ) for us to sleep in Friday night, and they came back and finished the install around noon Saturday (today). So, I haven't had time to test the Creative X-Fi expresscard further. Sleeping in the heat made me sick, so I'm going to bask in the new, efficient and expensive A/C for the rest of the weekend, until I feel better. My wife is sicker from it than I am, so I'll have to be helping her some too. I'll try to post something tangible early in the week. I also received a care package of items to test with the Zero, so news on that will be coming shortly thereafter. Have a good one!

What the Hell Penchum

first it's my AC acting up now yours goes for a dirt nap ?.......I hope it's not too expensive to replace (yeah right, there goes 2K quick). Mine is fixed, finally...after third visit and told the guy what to do (lol, no really).

I'm compiling the notes for the HDAM/627/LT1364 Head amp (blah blah) as I type this reply. I'm going to post it ASAP in parts. Part "I" is almost ready (hey I type slow). Part II will come later this week. Part I is HDAM/627/LT1364 Head amp comparison.

Part II is just HDAM/627 in dac section.

Be up later tonight if everything works out ok. T-Storms around here every day so I have to keep shutting everything down. PITA.

Peete.

PS Sorry for taking so long on this fellow SQ junkies !!

 

[oatmeal769]

Hurry Peete, HURRY!!

 

[Pricklely Peete]

HDAM/OPA627BP/LT1364 Mini Review for Zero DAC/Head AMP

PART I

The long awaited mini review, is for the most part, complete. Part I will compare the HDAM module in the DAC section of the Zero with the well known BB OPA627BP opamps on a brown dog adapter. The Head Amp section of the Zero with use LT1364's. All (or most) agree the combination of OPA627 + LT1364 makes for a very good listening experience when used in the Zero. Thanks to those that have spent countless hours investigating the dizzying array of models and makers. Tip of the hat to those contributors

Without further adieu, here is the review............

Source material : Music, Dream Theater - Six Degrees of Turbulence (thank gods it's not flatulence), Gladiator Soundtrack from movie, Jeff Beck - Jeff Beck's Guitar Shop, Portishead - Portishead, Peter Murphy - Deep. All of these have been listened to with each combination at least 3 times. Yes that took forever.....but hey I want to be thorough.

Source Equipment : JVC-XV-FA92 DVD-A digital out via Better Cables Silver Serpent Coax (.5m) to Zero coax input. Head amp output to Sennheiser HD650's (with 700 hrs on them and counting).

Configuration A : OPA627BP's in Zero DAC section, LT1364's in head amp. 50 hrs burn in, 45 hrs of music,24 hours of critical listening.
Configuration B : HDAM in Zero DAC section , LT1364...you get the idea. 100 + hours burn in, 100 + hours of music, 24 hours of critical listening


Volume Level for Head Amp output set to nine o'clock position for all testing purposes. Works out to around 84 db spl give or take a few db*. *Entirely recording dependent.

Part I : Config A

The OPA627BP for all it's on line buzz and storied rep delivers a multitude of positives where SQ is concerned when used in the Zero's DAC section. From the listening notes concerning Dream Theater......very tight detailed bass, lively dynamics although a tad recessed, missing the last ounce of slam that my main rig delivers (not bad considering the Zero costs less than a set of primo NOS tubes for the pre amp). The kick drum is taught, not over done , has no over hang at all. Although, slightly relaxed when it comes to the presentation of percussion. It's an impressive feat, none the less, to deliver that level of sophistication for such little money (really....what's 40 bucks these days for killer SQ ? ). What I did notice as far as negatives are concerned are rolled off highs, a metallic sheen or edge given to cymbals and brush work. You know I don't think the OPA627's are entirely at fault here for that.....the head amp section might be influencing the overall SQ a little too much ( see part II ). Still the BB opamps are an unqualified bargain imo for what they do right and boy do they do it....to it, so to speak

The BB is neither dark or bright IMHO, it seems to ere on the side of caution when faced with highly complex passages, meaning it handles them by compressing the sound stage and dynamics ever so slightly**. (**This trait might be a limitation of the Zero's power supply....) Imaging is very good , easy to place instruments and vocals in the recordings. Live music is a mixed bag at times, not the opamps fault most of the time since recording quality and the habit of re recording parts on live albums makes for a confusing mess with regards to imaging and the ability to discern nuance. When the recording is good the BB opamps do a very fine job of locating things where they should be. Vocals can be a tad forward but without that annoying spitty S or P sound we all dislike. High praise indeed when sibilants can be tamed and not accentuated. Male and female vocals are handled with equal abilities, very good in other words. On the Gladiator ST I noticed a very low signal to noise ratio, almost nonexistent, instruments and voices emerge from out of the black with an airy, ethereal quality I find unique to the OPA627. Dynamics seem compressed slightly again......hmmm OTOH brass instruments sound just right, lovely in fact.....The female vocals on this recording are by one of my favorite artists......I could listen to Lisa with the OPA627's in the DAC until my hair turns gray and love it. The BB opamps seem to paint music with a signature sonic characteristic.......polite , relaxed, detailed,slight upper mid recess, very slight roll off of the highs. Bass on this recording was (IMO) way way overdone, pitty, as it masks the excellent acoustic bass work of the symphony. Strings have that airy quality but lack the edge they do have live. I blame that on the over produced recording once again. Piano sounds very nice but is missing some weight with a hint of being brittle (very very slight). Might be another production mistake......anyhoo...On Jeff Beck's amazing lead guitar works on Guitar Shop, the BB opamps deliver JB's signature harmonics with aplomb, easily sorting the complex harmonies without making it all sound dis jointed. Thoroughly enjoyed this record with the BB/LT1364 combo. An interesting observation during the opening cut, the male vocalist almost startled me with the realism of the lyrics. Kinda hard to explain that one. The opening track isn't really sung, rather talked...anyway it's hyper realistic and rendered beautifully by the BB627's. I have a laugh at my own expense every time I play this cut and get startled all over again....The OPA627BP's 3D aspects, rather the level of detail retrieved from the recording allows one a glimpse into the artist/engineers conception of the piece. This is a relavatory aspect of a good amp and for the Zero with the BB upgrade to deliver this information at the level that it does it is the mark of a well designed piece of gear and a top notch opamp. The 627 is very very good, combined with the LT1364 in the head amp section, for less than 200 bones ? Amazing deal. Is it a giant killer....no but the Zero easily punches a few classes above it's weight. The OPA627BP(and AU's) are an excellent opamp. I'm highly impressed with their abilities. I could easily live with it's minor drawbacks if it were not for the HDAM module and what it brings to the table. With that we arrive at ......

Part I : Config B

When it came time to re-install the HDAM and power the Zero back up....The first and most obvious distinction is the HDAM's utterly unrestrained liquid smooth delivery of dynamics. I can't stress enough how impressive the HDAM module handles extremely complex passages without a hint of strain while maintaining the imaging and air. There is no compression of any kind, the instruments seem to breath along with the artist handling them. From the faintest whisper to a thundering climax, the HDAM just cranks it out as it is recorded (for good or bad) without additional color. The HDAM can sound both powerful and delicate at the same time, basically whatever you throw at it the HDAM doesn't seem to break a sweat. Piano sounds superb with the HDAM, absolutely life like, the complex harmonics of this instrument notorious for being difficult to reproduce even with the best gear is handled by the HDAM without batting an eye. Mozart sounds wonderful.....The layering aspect of modern multi tracked recordings is both a blessing and a curse with the HDAM. Fortunately there aren't all that many really horrid CD's/LP's out there. Let's focus on the what was mentioned earlier in the 627's config. Where it is possible to see into the Artist/Engineers concept of the recording the HDAM takes that level of insight all the way. Not only is left and right placement clearly rendered you get height,depth and individual FX types used on overdubs etc etc. Astounding realism. With electric guitars you can easily distinguish between the bright/sweet sound of a strat maple neck/alder body set at the neck pick up, and with all those sounds in between the 5 way switch. You can also recognize the difference between a Les Paul Standard with it's darker sounding cousin, the 57 Les Paul "Black Beauty". Very subtle shadings like these are the HDAM's hallmark IMO. Effortless is a word that keeps popping into my head every time I listen to Zero with the HDAM installed in the DAC section. I can't seem to find a single negative trait for the HDAM SQ wise.....
I've tried to find something...for days and days I've thrown every type of music I have at it. It doesn't blink at all. I have to wonder what a LD MKV would sound like with it's opamps swapped for HDAM modules. The more I think about that the more I want to try it

.....Back to the Zero....Mids are outstanding,highs are outstanding,bass is outstanding.........you get the picture. My conclusion is thus....the HDAM is simply in another league all it's own. I don't think it's fair to expect the 627 to compete with the HDAM at half it's cost and yet if you decide to go with the 627's in the DAC section you'll be getting about 75% of what HDAM offers. Is that last 25% worth of performance worth double the cost of the HDAM over the BBOPA627's ? An unequivocal YES IMHO.

As for the DAC section influencing the head amps output, ? I'd have to say without a doubt it does. The HDAM/LT1364 combination is outstanding in the Zero. The OPA627/LT1364 combo is merely great

Either config is an excellent choice. I'm keeping the HDAM in the DAC section if you haven't guessed already

. I'll have to try the 627s in the head amp section next with the HDAM feeding it

Part II to follow.....in a few days

Peete

 

[windrider]

great review.

In your opinion how would you rank the following 2?

- zero opa627dac + LD MKIII
- zero HDAM + lt1364

 

[Pricklely Peete]

Quote:

Originally Posted by windrider /img/forum/go_quote.gif great review. In your opinion how would you rank the following 2? - zero opa627dac + LD MKIII - zero HDAM + lt1364

Thanks for the kind remarks !!

My set up is JVC DVD ---> Zero HDAMdac --->MF X10 v3* + MFX-PSU ---> LD MKIII ---> HD650's with stock cable. (*Pink Floyd cap and diode upgrade kit)

The 627 + LD MKIII would rank first from your list. Since I have a HDAM the obvious number one ranking for me would be...

1) Zero HDAM/dac + LD MKIII
2) Zero OPA627/dac + LD MKIII
3) Zero HDAM/dac + LT1364

Best Regards,

Peete

 

[Archimago]

Quote:

Originally Posted by Jazz9 /img/forum/go_quote.gif Do the LT1364 need heatsinks even in the headphone amp? I think I'll first try lt1358 in the dac+lt1364 in the amp when my zero's burn in is over and if I'm not satisfied I'll get the opa627 (I'll get them even if I'm satisfied I'm sure just to see how good they really are )

As someone else mentioned, LT1364 in headphone amp does get warm but not as hot as DAC section.

I stuck a Zalman ZMRHS1 heatsink on each one (originally meant for VGA memory) and now can hold my finger over them all day.

Looks like one more day before the OPA627's arrive .

Pete: Damn you and your HDAM review temptations! I haven't received the 627 yet and already looking at these Burson eBay ad's . However, I agree with Penchum about needing the lid closed... Too many little kids to risk the shock hazard of an open box!

 

[deuginthesky]

Quote:

Originally Posted by Penchum /img/forum/go_quote.gif It is just ANDREA again. Please ignore him. There were a few comparisons earlier on, but I don't remember the model numbers. Anyway, the Zero did pretty well, considering it cost less and had a better headphone amp by default, so no one thought too much on the subject.

From what I,ve seen, the Zero and Zhaolu D2.5 any version have the same headamp.
I have a D2.5A, just seen pics from the Zero headamp board, they look exactly the same to me.

 

[pincellone]

Quote:

Originally Posted by Pricklely Peete /img/forum/go_quote.gif What the Hell Penchum first it's my AC acting up now yours goes for a dirt nap ?.......I hope it's not too expensive to replace (yeah right, there goes 2K quick). Mine is fixed, finally...after third visit and told the guy what to do (lol, no really). I'm compiling the notes for the HDAM/627/LT1364 Head amp (blah blah) as I type this reply. I'm going to post it ASAP in parts. Part "I" is almost ready (hey I type slow). Part II will come later this week. Part I is HDAM/627/LT1364 Head amp comparison. Part II is just HDAM/627 in dac section. Be up later tonight if everything works out ok. T-Storms around here every day so I have to keep shutting everything down. PITA. Peete. PS Sorry for taking so long on this fellow SQ junkies !!

I personally believe that in most cases HDAMS represent a step backwards in audio electronics. Of course, this is not always the case, but there are some quite decent opamps around that can outperform the discrete ones now.

Beware of the marketing hype...

Just to give you an example, do you really believe that Burson carefully designed the HDAM that they are selling?

If so, then check this out...

diyAudio Forums

Surprised?

I'm not. Happy listening.

 

[Penchum]

Quote:

Originally Posted by Pricklely Peete /img/forum/go_quote.gif What the Hell Penchum first it's my AC acting up now yours goes for a dirt nap ?.......I hope it's not too expensive to replace (yeah right, there goes 2K quick). Mine is fixed, finally...after third visit and told the guy what to do (lol, no really). Peete. PS Sorry for taking so long on this fellow SQ junkies !!

Complete system replacement: Over 7K with tax. I got 20 years out of the old one, so that is about 5 more than normal. Still, it will put a burdon on things for a while. Damn! Can't live out here without one, so "ka-ching".

 

[Penchum]

Quote:

Originally Posted by Pricklely Peete /img/forum/go_quote.gif HDAM/OPA627BP/LT1364 Mini Review for Zero DAC/Head AMP PART I Snip for size... Part II to follow.....in a few days Peete

PP,

One hell of a impressive review!!!! Thank you so much for taking the time and effort to "bring" it all together. You absolutely have my ears! Your description of the OPA627BP is so much like my understanding, it's freaky!

One thing I wanted to point out to the readership, is the rating of the OPA627BP vs. HDAM module. PP says the 627 is about 75% of the HDAM, and I'm sure this is correct. This isn't a statement that the HDAM rated at 100 is the best thing on the planet earth, better than all others. That rating is only to "scale" the performance of the two items in question, against each other. Be careful you don't read into what is presented. PP has been VERY clear in his presentation, and I salute him for that!

I can't hardly wait for the next part!!