Proper DAC Break-In?

[Egon]

What's the best way to break in a DAC? For speakers, I use pink noise or an AM radio station that's fuzzy. For this, can I just put my playlist on random repeat, or would full-frequency pink noise make a difference?

 

[rom661]

Egon, this is a subject that I have often wondered about. I owned a high end store for many years and the subject of break-in is even more pressing when you realize that you may lose a sale due to an evaluation done with a piece not fully run in.

 

My suggestion is wide frequency range music with dynamic contrasts. I usually use my rock/blues playlist. The question I have always had on source components is if the entire system needs to be on and playing. Dave Gordon of Audio Research states that break in is faster when there is current passing through the output stages, which implies that everything is on. I just finished the process on their DAC7, which has a recommended break in of 600-800 hours which is daunting in itself plus my preamp is a tube piece. You could probably set up a dummy load approximating the input impedance of a preamp and do the same thing and save wear and tear. Speakers, unfortunately, need to move.

 

Like you, I would like to be more certain.

 

[souptin]

What's the theory behind 'break in' or 'burn in'?

 

I'm alternately curious, baffled, confused, surprised etc by the whole idea.

 

For example, I have kept my 10+ year old cd player and amp switched on almost without a break since I bought them (as per manufacturer's recommendations), but I wouldn't dare to the same with my computer related gear because I reckon all those wall warts would melt! Now I would swear that on the rare occasions I've switched off to move the main gear, it does not sound noticeably different just after switch on. But after an hour listening everything sounds better - so is that the equipment warming up, or is it my ears that are warming up?

 

Similar thing with some new headphones I got recently. As per Grado's recommendations I left them playing almost non stop for a couple of days. Did they sound better? Yes, I think so, but I also think that they are sounding better the more I listen to them. So again I think at least 50% of the burn-in phenomenon is getting used to the tonal character of the phones. Sometimes I think that the burn-in idea has become a self perpetuating myth, particularly from solid state equipment - I say 'self perpetuating' because I suspect that if a high end manufacturer's engineers said that a particular piece didn't need burning in, the marketing people would insist that it did because otherwise people wouldn't think it was truly high end.

 

I suppose from the point of view of a dealer the best bet would be to have the time and space to allow for extended auditioning of equipment, then your customer has time to relax as well as giving time for things to warm up. Sadly commercial pressures can make space and time very costly on the high street. But leaving your entire stock playing overnight sounds like a recipe for disaster. One faulty transformer and everything goes up in flames, and even if it doesn't you'll be getting serious grief from the neighbours.

 

[Purite Audio]

The theory behind burn in, you buy something new, it sounds terrible, you complain to the shop, they say it has to 'burn in' 600-800 hours! By then you are either a,dead, b., deaf or c, don't care any more.

Tell me what is in a dac that needs to 'burn in'?

 

[Egon]

I appreciate this site so much. I expected a simple "Yes/No" obvious answer, and instead got conversation and learned something.

I can only imagine the pressure on your shops. As much as I love to listen and talk about music and compare equipment, I wouldn't want that part of it.

My speakers are several years old and were the first pair I had that stepped out of mass consumer types. I heard a huge difference with break-in and am a believer in that. Also, my DAC has opened up and gotten more airy and dynamic in the few weeks I've owned it, so clearly there's something going on here. Two different sounds from when I first bought it, though both pleasureable.

So, I'll put a jazz or dynamic playlist on repeat, turn off the (years-old) amplifier so as not to bother the neighbors, and see what other secrets this DAC will reveal with time.

 

One more specific question... the DAC has coax, optical, and USB inputs... do you think each input must be broken in individually? What's your gut feeling since I doubt there's science done?

 

[Audio_ELF]

There is no doubt that speakers can break in ... they contain physically moving parts that will change as they are used.

 

Electronic components are more doubtful about the benefits of breaking in. Anyway I'd just play some music through them. Even if it does need breaking in ... just using it will do that. It maybe that you think it sounds better over time because you are getting used to the nuances of it's sound, or the performance might change a little. Either way there's no downside to breaking a component in - unless it's a limited life span component I guess, but then even valves have 10,000 or more hour life span these days.

 

Eloise

 

[rom661]

I have heard hundreds of electronic components change as they get some time on them new out of the box. Some are fairly subtle and don't take long. Others are the reverse. Usually the first 50 hours or so are most significant and the curve seems to flatten out to the point where you question hearing a continued difference. The Audio Research piece is the most extrememe I have ever heard in terms of length. By the way, ARC admits they don't know why it takes so long, which is OK as long as you know what to expect.

 

I had a Mark Levinson No.30 in my personal system many years ago and was dismayed when it sounded worse after three days than fresh out of the box. Tech support assured me it was normal and sure enough a few days later it was much improved.

 

It is pretty commonly accepted that capacitors go through a process known as "forming" and this is responsible for much of the break in. Speakers networks are full of capacitors plus the additional issues of mechanical break in of surrounds, spiders, etc. I have seen raw drivers on the bench whose resonance frequencies changed by as much as 20% after 48 hours of 20 Hz fairly high level sine wave.

 

I do agree with you that some electronics don't seem to do much more than warm up. I've never fully understood the variables but have witnessed the more pronounced break in too many times to doubt it.

 

Best wishes

 

Rick

 

[rom661]

I wish I could give you a definitive answer. Much of the circuitry is shared by the inputs so I am going to hazard a guess and say that it is less important to worry about the individual inputs. I will call a couple of manufacturers who are great sources of info and see what they have to say.

 

In preamps you are only talking about switching unless it's a phono input, but DAC's could be different since they are different types of signal.

 

I should know the answer to your question and this will make me get off my duff and check it out.

 

Rick

 

[rom661]

If you feel that way about the shops you deal with, maybe you should find someone else. I have always advised my customers whether the burn in is insignificant or major, depending on the product and what is appropriate. I left another post speculating why, but I have heard it countless times. And I have just witnessed the longest burn in of my experience on my own personal piece, with no ax to grind. We virtually never sell a piece without a demo, home loan, or both, so our customers already know what the piece will sound like.

 

Sketicism/cynicism does have it's place in this industry but it seems you are painting with kind of a wide brush. And 600-800 is atypical. On most electronics I tell customers if you don't like it after the first 100 hours, you probably aren't going to since usually there are incremental changes, if any, after that time. Do keep in mind that I am biased, although hopefully honest, since it is my industry you are impugning.

 

To your final question about DAC's, I don't know but for some reason the product category, based on my experience, is more, not less, demanding of break in.

 

Best wishes

 

[Purite Audio]

Capacitors do have to form you are correct, this takes milliseconds, electro mechanical devices, ie drivers and cartridges may take a time to reach their optimum. New valves take a while for the 'getter' to completely evacuate any remaining gas from the tube, I can even believe that a few minutes wait for a device to reach its optimum operating temperature might be worthwhile, but 600-800 hours come on!

In fact electronic components like capacitors are already at their optimum and only degrade with use.

What is actually happening is that your ears just get used to the new sound, and if you were to go back to the old component they would again have to readjust.

 

[rom661]

We will have to agree to disagree. Part of what I am basing my experiences on is comparing a new piece, as it gets some time on it, to other pieces in the store, so there is a form of control. If a new piece "a" sounds brighter and less refined than comparable piece "b" in the beginning and after a period of time that difference changes, (hopefully for the better) I believe it is the newer one that changes. Having said that, I have observed this hundreds of times.

 

I think what you are describing does happen, especially when you are replacing a piece in your home whose sound you are accustomed to. I might listen to a half dozen preamps on a given day and constantly am adjusting to the paradigm shift you are describing.

 

By the way, I am pretty conservative about this matter compared to many in the industry. The 600 to 800 hour thing I would typically take with a grain (or two) of salt. I have the piece in my home and have compared it to another $3500 DAC periodically as it broke in. The manufacturer says 600 but it took longer. Suddenly (over the last couple of days) the differences between the two changed noticeably. It is the first piece I have ever encountered that had clearly noticeable changes after that length of time.

 

At any rate, this is all subjective to some degree and you are entitled to your opinion as I am to mine. I suspect that our difference in opinion on this will not adversely affect quality of life for either of us.

 

Best wishes

 

[Steelman]

The Lavry Gold 924 DAC uses an interesting warm-up and automatic calibration processes to deal with temperature variance and component aging issues:

 

http://www.lavryengineering.com/white_papers/DA924m.pdf