[taso89]

I don't wanna believe in it but for the first half-hour I did notice some weird variations in channel balance, then the bass disappearing, etc. It's settled down now though.

I hear 100 hours is typical burn-in for an IC?

 

[AudioPhewl]

1s is typical burn-in for an IC IMO.

Think of the CPU in your computer - it's far more delicate than an opamp. It runs at speeds of 3ghz or above, covering a wide-range of possible temperatures, and does a heap more critical work than a simple opamp.

Despite all my years as an overclocker, I've never known a CPU that has improved with age or use. They work from the off, and do so without any problem. Opamps are the same, IMO.

The differences you believe you heard could be attributed to the change in temperature - opamps generally run quite a bit warmer than room temperature.

~Phewl.

 

[pincellone]

Quote:

Originally Posted by AudioPhewl /img/forum/go_quote.gif 1s is typical burn-in for an IC IMO. Think of the CPU in your computer - it's far more delicate than an opamp. It runs at speeds of 3ghz or above, covering a wide-range of possible temperatures, and does a heap more critical work than a simple opamp. Despite all my years as an overclocker, I've never known a CPU that has improved with age or use. They work from the off, and do so without any problem. Opamps are the same, IMO. The differences you believe you heard could be attributed to the change in temperature - opamps generally run quite a bit warmer than room temperature. ~Phewl.

You are right. Burn in makes no sense at all for opamps , but sometimes it makes believers happy, therefore it's good somehow...

 

[pincellone]

Quote:

Originally Posted by taso89 /img/forum/go_quote.gif I don't wanna believe in it but for the first half-hour I did notice some weird variations in channel balance, then the bass disappearing, etc. It's settled down now though. I hear 100 hours is typical burn-in for an IC?

What? Who said that? Why not 110 hours instead?

Sorry, no need for burn in with ICs. Silicon burned a lot already for a few million years.

 

[Penchum]

From testing so many Opamps, the ones that seem to have the most variation (still small though) are the ones that are two single DIPS on an adapter. The very small AU packages don't share this same odd property though.

Another good reason for "maturing" all Opamps, is so that both believers and non-believers can understand and believe the results you have come up with, when testing Opamps. It leaves no room for doubt in their minds.

HDAMs for sure, need time to mature. Since they are "working" the signal, I'm under the impression they should be working on something when "maturing" them. I have not heard what percentage of their operation is only "heat affected", but I'm still researching that one.

I did read somewhere that it was thought to be 300 hours for burn-in, but the audio-gd I got, seemed to take a little more than half of that. When I did the "cap" mod, that silly cap took longer to form up than the whole HDAM did!

Oh well, I should have put it on at the beginning anyway!

 

[Penchum]

Quote:

Originally Posted by taso89 /img/forum/go_quote.gif My LM4562's are coming in tomorrow, and the OPA627's came today. I'm very happy with the OPA627 and can't wait for it to burn-in. The first thing I noticed was more detail but also less NOISE at extreme volumes. LT1469 in the DAC had significantly more noise at high volumes. If the green preamp light is on and I have music on, do I need to have phones plugged in for burn-in to occur?

If you are using the pre-amp function (volume controlled by Zero, green light on) then both DAC and Headphone amp Opamps are involved, so you are good to go.

 

[andru]

Received my head fi zero in 6 days from Lawrence, very satisfied with it!

I don't notice the channel imbalance at all even at low volumes so it's not a problem whatsoever. Came with an Australian power plug as well which was a nice touch

 

[wcp6]

I have a question as I am fairly new to amps (read: never owned one and my zero has arrived in american customs earlier today.)

I have a pair of DT770's that are burning in right now, but they are loud enough for my use with the windows volume only at 20. If I use the zero, then, I assume I will have to keep the volume very low? I have also heard that it is best to run digital with 100% volume to stop any degradation of the digital signal itself. Is it going to significantly lower sound quality?

For some reason, both my HD515's and DT770's get VERY loud out of my standard headphone out on my Razer Barracuda AC-1 card, but I also noticed it on my previous onboard realtek with my HD515's (recently got 770's, the onboard is toast)

It's just seems strange to me and I want to make sure nothing will be degraded due to the 80 ohm impedance only of the DT770. The HD515's have only 30ohm impedance

thanks for any advice

 

[NumpXP]

is that the toroidal wire that causes the vibration in zero? what's its function btw?

and lastly, my usb/spdif converter is just capable of 48KHz 24bit convertion, am i losing much compared of that 192KHz?

thanks

edited: Oh, the toroidal wire is the transformer. So i suppose it convert AC to DC, am i right?

 

[decayed.cell]

Come to think of it the SVDAC05 is sold by wsz0304 for only 1 USD more. Probably not the right place to post but how does the headphone amp work in this?

 

[Enthusia]

This thread is not to post your boasting and comparisons with the Zero Dac. If you really think there are other dacs that are better at around the same affordable price, then good for you! Start a new thread and do a review, other than that, let's stay on topic.

 

[Penchum]

Quote:

Originally Posted by Enthusia /img/forum/go_quote.gif This thread is not to post your boasting and comparisons with the Zero Dac. If you really think there are other dacs that are better at around the same affordable price, then good for you! Start a new thread and do a review, other than that, let's stay on topic.

Andrea again. Same ole' Sheit.

 

[gavszero]

My babies were delivered today , a boy and a girl .. Ok jokes aside , my OPA-SUN & OPA Earth arrived from Audio-GD . I got an email from Kingwa on Monday and arrived today Friday with Priority DHL and was well packaged .


First thing I did was to slot in the SUN to start burn in .. I made sure everything was ok by testing a CD and through in Steely Dan Two Against Nature. Immediately I noticed the cymbals , Hi Hat open and closed , Snare drum was so much more clearer and very Natural . Bass extension was also improved over the OPA627 . It's still early days as I have only 10 hours on this module . I'm confident that these Discreet opamps will be staying in my Zero , it's just too good to compared to the IC alternative . If anything I might have to get a second Zero for the Earth and switch between the two depending on the music i'm playing . I could choose the Earth for warm natural and the SUN for more Dynamic sound ..


When I got my Zero I burned in the Zero with the stock opamps ( OPA2406 ) and found it better then my soundcard ( Terratec DMX6fire & Terratec DMXfire 1024 ), and possible better then any sound card analog ouput . So for anyone on a budget this will be better then your soundcard .


I then borrowed the OPA627's of a friend and was a hugh difference over the stock , found it much more natural to the stock opamp. Going by many in this Forum have found this opamp to be the one to have other then the Hdams but are expensive for what they offer compared to free samples . Actually it'll be better to get your Hdam order in as Audio -GD have extended their 2 for 1 offer , you won't regret it ..


When my LM4562 samples arrived I slotted them in and left the unit on my Pay TV Set top Box on the Music channel to settle in these new opamps and found them to be very Dynamic . It was as if I switch on the loudness swicth on older amplifiers . The bottom and top end seemed to be boosted giving a sence of a larger sound stage . With Steely Dan I found this opamp it was like shooting the snare drum into my face it was so forward .If you had laid back speakers this might be a good opamp to give them a lift , good thing about these is you can get 3 samples for free ..

I'll leave my OPA-SUN in to burn in for another 4 days to get to that 100 hour mark , i'll then hook up with my friends Zero with the earth installed and will do a switch on the fly using 2 inputs on a preamp to test the difference . I find when I stop to swap opamps it's harder to fine a small difference if there was any ..

I have to say inside my zero now looks like a Chrsitmas tree with the added 2 green LED's on the OPA-SUN module ..

I know most here are looking for a budget unit , I've gone one step further and bought the Buffer 3 to have better impedance matching between the Zero and preamp to further improve . I've read nothing but good reviews about buffers and Audio - GD has this new model .. See how it goes anyway , should get it next week ..

I'll have to do the LED mod on my zero , when i'm burning in the hdams in my room , I don't need a light , those LEDs are so bright . I've bought some 5.6K ohm resistors to replace ..

I haven't done much with the amp section as I don't have any decent headphones to take full advantage of this amp . Will be looking forward in picking up a pair of HD650's in the near future ...

Anyway I'm off to listen to some more music .. Just can't stop going through my collection since you lot got me addicted to the Zero ..

Gavin ...

 

[Penchum]

Quote:

Originally Posted by gavszero /img/forum/go_quote.gif My babies were delivered today , Snip Gavin ...

Nicely done Gavin!

I'm glad the "Sun" sounds like a winner too! The LED mod is so highly recommended! At one time, I had both of my Zero's running at night, and it was so "BLUE" in this room!

I've modded them both and it has helped a bunch.

Keep us informed on the side by side comparison you do. It will be interesting to hear your take on how they differ. Thanks!

 

[ccschua]

Quote:

Originally Posted by Penchum /img/forum/go_quote.gif I have to ask, why do you believe it can be properly burned-in with only power applied? Thanks!

Hi,

This may not apply to all the OPA, but opa earth and sun is exception.

If you check through OPA Sun/Earth circuits from the audio-gd website, it is in Class A. In electronic circuit, there shouldn't be distinction between power and signal. Signal is only used to control the amount of output and the signal is working always with some bias current. Only Class B or D and others has no output signal (perhaps due to efficiency). Only when signal is apply, there will be changes in the output. The flow of bias current is sufficient to burn in the electronic components.

I hope to explain but I may miss some points. Hope to hear your finding regarding this matter too.

rgds