Why does it take so many hours to brea in arc preamps and amps?


I recently purchased a like new ARC 5 SE pre amp.  The unit had less than 200 hours on it.  Everything I have read states that ARC preamps take up to 600 hours to fully break in.  Why is this so and what improvements can I expect to hear as the unit accrues hours?
ewah
@georgelofi

Yes, it was on a red warning sticker on the outside of the DAC 8. Well, not a sticker so much as a big red sheet taped to the outside. Clearly they intended buyers to see it before making up their minds. 

That DAC is long gone, and I had purchased a floor model from the local dealer, so I can't tell you if I thought that was real or not.

It not only claimed 500 hours for the DAC, but per input as well.

Best,

E
It not only claimed 500 hours for the DAC, but per input as well.

Sounds like Ralph’s "expectation bias" to me. By that time not only would a trial period be over but the warranty as well with some.

Still not advertised and written on a web page link by the manufacturer.

Just like the mains fuses that are "said" to have to be "broken in" and also to be 'directional" by manufacturers, yet try to find any of that advertised on a site by them.

Cheers George
" I’m not talking prototypes, it’s production ones I’m referring to.
And the way your inferring is that the production ones are deliberately out of adjustment/calibration to factor in "break-in" period, which after those adjustment/calibrations are magically back in spec?? I think not. "

How could you possibly get that from reading my post?

You have to have prototypes in order to get to production. Here's how it works. A designer puts together a prototype. Before he listens to it, he breaks it in first. Any further changes made to the unit under development, gets broken in before the changes are evaluated. The last prototype is the production model. Through every process of development, the unit gets broken in before listening to it. That includes the final production model. For example, if the manufacturer claims 500 hours for break in, that's the standard. So, when they sell an amp to a customer, the customer need to put 500 hours break in time on it. After that, the customer and the manufacturer have an amp that sounds exactly the same.

Also, I never inferred that production units are deliberately out of adjustment/calibration. What's to adjust? Break in is a passive process. I just don't see what's so complicated about all this. If you don't believe in break in, fine. Its an issue that will take care of itself over time regardless of belief.

How could you possibly get that from reading my post?


From this, as it infers that it’s in prototype stage. When a product is finalized there are no changes to be made once in production, as it’s all sorted.
When a designer is building a new product and makes changes, the component gets broken in before they listen to it.

And your talking 600hrs for each change in the prototype.
Any further changes made to the unit under development, gets broken in before the changes are evaluated.


Cheers George
Again, I'm not sure where you are getting this info from.

" And your talking 600hrs for each change in the prototype.
Any further changes made to the unit under development, gets broken in before the changes are evaluated."
600 hours? Where did I say that? I've never had an ARC product take that long to break in.

" From this, as it infers that it’s in prototype stage. When a product is finalized there are no changes to be made once in production, as it’s all sorted. "

You're stating the obvious. Besides, I already addressed that in my last post. The last prototype is the production model.

Since you want to go back to my "where did you get this info from" question, you're conveniently leaving out the portion of my post that's most relavent to the question.

" And the way your inferring is that the production ones are deliberately out of adjustment/calibration to factor in "break-in" period, which after those adjustment/calibrations are magically back in spec?? I think not. "

Show me where you got that from.

" To all those that say the manufacture has specified a certain "break-in" period, please link the rest of us to those manufacturers links, instead of it being just personal opinion. "

I just noticed that.

Ayre

Due to the manufacturing processes used for the wires, capacitors, and circuit board materials, a break-in period is necessary for the amplifier to reach its full sonic potential. 100 to 500 hours of music played through the system will ensure full break-in.

Theta

Getting to know your Dreadnaught D This Dreadnaught D has been put through a rigorous and unique testing procedure that ensures that it will last for many years with minimal service requirements. This procedure includes the following: •All assembled circuit boards are given a thorough visual inspection and are then tested in a bench-reference Dreadnaught D. •The tested, assembled circuit boards are then installed in a new Dreadnaught D and the whole unit is tested for every function and parameter. •The unit is put on a burn-in torture rack to test for any possible component failures. •It is then tested on an audio analyzer for all pertinent parameters. •The unit has all remaining chassis components installed and then undergoes a complete visual inspection, which assures that all Dreadnaught D’s meet visual specifications. •The Dreadnaught D then undergoes a critical listening and functional test. Burn-In Time While the Dreadnaught D amplifier will sound wonderful without any burn-in time, users may experience small sonic improvements during the first week or so of operation.

Burn-In/Break-In Time This unit has a break in period of about 1 week during which continuous improvement in sound quality will be observed. It is recommended that music be played continuously through the unit during this time to expedite the break in period.

Aesthetix

BURN IN TIME This unit has a break in period of about 1 month during which continuous improvement in sound quality will be observed.

There's 3 examples. If you want more just read an owners manual. Also, when you read through the Theta example, the break in requirements are different for Class D amp than traditional AB.