Is There a Breaking-in Period for an Amplifier?

[Johnny2Bad]

Man, first post since registering in 2008? Really biding time for that response.

Also, mentioning thermodynamics then typing the word "coldening" takes away from credibility.

As for the rest of this discussion, I'd really like to see if there is any measurable merit to this argument. It would be very interesting if an amp performed differently after being subjected to a difficult load during a specific amount of "break in" time. Measure before and after. We'd have an idea of an answer.

This seems like something the AH staff could do easily enough. Granted, I'm willing to be if they told the manufacturer what the plan was they'd hesitate to provide review samples.

An easy answer for you ... check out the "FTC Rule" on amplifier power. This required a pre-conditoning at one third rated power for one hour (changed to one sixth under pressure from ... wait for it ... home theatre manufacturers ) ... before any measurements were taken. Established in 1974 to counter wild, unsubstantiated power claims.

Note as well that an FTC Rule compliant specification requires the amp cannot specify any power rating into an impedance that caused the protection circuit to trip, blew a fuse, or exploded spectacularly on the bench, as the case may be. So if it could do a 2 ohm load out of the box, but not after reaching operating temperature, you can't give any power rating into 2 ohms in the spec sheet. It's more common than you think for amps to misbehave during testing for compliance; you just don't know because the conditions that caused it cannot be mentioned in specifications.

Ironically, today most manufacturers ignore the FTC rule (and anything sold on eBay from China doesn't even follow the watered down test spec they do use today) because the HT manufacturers went all legal on the FTC who had the misfortune of specifying mono or stereo amplifiers in the rule back in the early 70's ... which they claim means it does not apply to an amp with more than two channels.

For something more elaborate, you probably would have to do your own measurements. The HiFi component manufacturers do their own and know the details, but they have no reason to give that data out. For what it's worth, Bryston bench-burns all it's products for 24 hours before testing and throwing the specific serial-numbered test results in the box with the product. There must be a reason; this is an expensive routine to follow. Many other quality manufacturers do employ a similar routine.

Why not longer, why not for the 200 hours (or whatever) some recommend for burn-in? Well, that would go from expensive to really expensive; why not ship to the consumer and save him some money doing the same thing himself?

I've got an old NAD integrated that has sat for about 15 years. Maybe if I can get some free time I'll fire it up and see what results I get. I can measure THD+N to H5 with my Distortion Analyzer. The problem is, due to a move where others were involved in the packing, I can't find my Variac and I wouldn't want to power it up after such a long time without reforming the caps. But who knows, it might show up.

 

[Bucknekked]

Agreed. How much? This

Swerd:
I think you caught the spirit of the comment perfectly. I'm not sure others even noticed it.
I think an industrial sized load of Roundup would be required at this point.

Heating/cooling audible break-in amuses me. Just knowing it will have reached somewhat of that potential, perhaps to the extreme in some parts, just from the soldering process. Or the parts that need to be hand worked, where newb is just a little slower than the old hand next to him.

Except for perhaps in China, where they might earn a nickel for every board and can heat sink with their teeth. I bet those dudes are pretty fast.

MrBoat
An excellent observation. Too close to reality for some folks on this thread and therefore I'm sure they will pass it by. I'm with the pantergastk on this thread: the OP started off quoting thermodynamics and then followed it up immediately with the thought of coldening. Somehow the shine of using the big word is diminished by the followup from grade school. Dudes in China hand soldering parts does evoke images of "coldening".

This thread is starting to resemble the age old argument of "how many angels can dance on the head of a pin?".

 

[mtrycrafts]

What's the coefficient of expansion for concrete? I can't recall it, but I remember that it has a lot of zeros.

Yes, but think about those railroad tracks in the desert.

 

[mtrycrafts]

...

This seems like something the AH staff could do easily enough. Granted, I'm willing to be if they told the manufacturer what the plan was they'd hesitate to provide review samples.

Oh, I don't think they would have to ask for a component just for that test as this test could be part of any amp/receiver. Measure it as soon as it is placed on the bench, cold then run the tests, torture tests and then final testing when it is still nice and hot. They could also minimize air circulation around that component.

 

[highfigh]

Yes, but think about those railroad tracks in the desert.

You mean the ones that were welded with Thermite? Pretty sure that's the reason they aren't laid in a straight line for too long.

 

[highfigh]

HDMI is considered in spec if there is one data error every 8 seconds (with a 1080p data stream; it goes up or down depending on the data rate). In practical terms this is inconsequential if in spec (the bad pixels won't be onscreen long enough to be noticed with human vision), but will be a problem if the data is somehow corrupted; if the characteristic impedance is badly mismatched, etc. because the error rate can increase rapidly. This is one reason why you want a decent HDMI cable (or USB cable, etc); no need for snake oil but a certain level of quality is a minimal requirement.

How well or how poorly these errors are tolerated requires a solid background in analog theory, something that seems rare amongst the "bits is bits" crowd.

Apologies for the rant, but it feels good to get it out of my system ;-)

If HDMI is a one way com protocol, how would you explain EDID problems?

Had to replace a Redmere cable the two weeks ago because it stopped sending video to the projector- The only relatively recent change to the system was my replacing the AVR is June, but I set everything to 1080 and CEC/HDMI control are turned off. I went there (just a three hour one way shot) with a simple Vanco 35' cable that has just wires, not active circuitry and it works perfectly.

The original cable is from Key Digital and I bought it from a local distributor on Oct 6, 2014. It was supposed to have a 3 year warranty and they don't want to honor it because I didn't open a case for the problem. The fact that I had no way of knowing it was the cable and it's 3 hours away makes no difference.

Here's part of the response:

"If you are concerned about replacing a wire in-wall you may consider removing the HDMI heads and terminating with CAT6 STP RJ45 head as there are 4 individually shielded pairs (among other wires) inside of the Key Digital HDMI cable.

After terminating, you can use the cable with HDBaseT extenders. Our current recommended part is the KD-X222"

Really? That's basically "WE won't help you, but if you cobble it together with RJ45 ends and buy another product from us, that would be OK." Right. Your crappy cable took a dump and made my life hell and you want me to buy a $300 POS from you.

Vanco is less expensive, but they offer a lifetime warranty.

 

[highfigh]

Heating/cooling audible break-in amuses me. Just knowing it will have reached somewhat of that potential, perhaps to the extreme in some parts, just from the soldering process. Or the parts that need to be hand worked, where newb is just a little slower than the old hand next to him.

Except for perhaps in China, where they might earn a nickel for every board and can heat sink with their teeth. I bet those dudes are pretty fast.

RCA had a repair kit that included the solder because the original part's temperature limit was about 65 degrees F below the melting point of most solder used at the time.

 

[3db]

So has the question of amplifier break in been put to bed? Im just to lazy to read thru all of this

 

[mtrycrafts]

So has the question of amplifier break in been put to bed? Im just to lazy to read thru all of this

Just until it is time to wake up.

 

[Bucknekked]

So has the question of amplifier break in been put to bed? Im just to lazy to read thru all of this

3db:
If you don't think amplifiers need a break in period, or there isnt such a thing, the thread supported that view.

If ,however , you think amplifiers do "break in" and it can be "scientifically proven", well, the thread supports that point of view as well.

If you are like me and just can't muster up any give-a-poop-factor at all about this, my contributions to the thread support that third viewpoint.

 

[Johnny2Bad]

If HDMI is a one way com protocol, how would you explain EDID problems?

Had to replace a Redmere cable the two weeks ago because it stopped sending video to the projector- The only relatively recent change to the system was my replacing the AVR is June, but I set everything to 1080 and CEC/HDMI control are turned off. I went there (just a three hour one way shot) with a simple Vanco 35' cable that has just wires, not active circuitry and it works perfectly.

The original cable is from Key Digital and I bought it from a local distributor on Oct 6, 2014. It was supposed to have a 3 year warranty and they don't want to honor it because I didn't open a case for the problem. The fact that I had no way of knowing it was the cable and it's 3 hours away makes no difference.

Here's part of the response:

"If you are concerned about replacing a wire in-wall you may consider removing the HDMI heads and terminating with CAT6 STP RJ45 head as there are 4 individually shielded pairs (among other wires) inside of the Key Digital HDMI cable.

After terminating, you can use the cable with HDBaseT extenders. Our current recommended part is the KD-X222"

Really? That's basically "WE won't help you, but if you cobble it together with RJ45 ends and buy another product from us, that would be OK." Right. Your crappy cable took a dump and made my life hell and you want me to buy a $300 POS from you.

Vanco is less expensive, but they offer a lifetime warranty.

Well, I can sympathize with your issues, but to answer "If HDMI is a one way com protocol, how would you explain EDID problems?" ...

EDID (Extended Display Identification Data) is just that ... it is a set of read-only information about the display that can be read by the source device over HDMI. But it contains no *active* information about the data stream; it identifies the display itself and provides some information relating to that.

In other words there is the data that is being transmitted, one way, to the display, that consists of the program material. And there is the EDID information, that tells the source what kind of display it is (it too is one way, just the "other" way). The two are separate and not a two-way communication protocol about the data stream. So errors in the data stream cannot be actively corrected should they arise (save for error correction employed in the display that tries to make sense of what the data stream is sending).

EDID can contain things like the manufacturer of the display, serial number, date of manufacture, the resolution, and so on. It's a read-only laundry list of useful information but not a return path for data error correction.

As for problems related to EDID, it's common and EDID in general is not well supported in source components. Plus it's a bit buggy. It's part of a VESA standard that is incorporated into the HDMI standard, so that's half the problem right there. It's not technically an HDMI protocol but is allowed by the HDMI standard if implemented.

 

[Johnny2Bad]

Soldering does not employ any electrical activity, no electrons dancing about within a conductor or semi-conductor. No junctions; anytime you have one element meeting another element under electrical energy, noise is generated, as is heat, and a HiFi system is nothing if not an extensive network of junctions of dis-similar elements. The physics of such interactions cannot be duplicated by throwing the parts into an oven.

To equate soldering, whether by an iron, by resistive soldering, or wave soldering, to an active circuit is to mis-understand analog electronics. Burn-in is not simply applying heat to a device.

 

[MrBoat]

To equate soldering, whether by an iron, by resistive soldering, or wave soldering, to an active circuit is to mis-understand analog electronics. Burn-in is not simply applying heat to a device.

Hey, but if these ultra perceptive people can imagine all of these changes, they really ought not leave nothing out. I wonder if they notice the difference of when the new electronics smell gets cooked out of their electronics too. I mean, surely their sense of smell must be killer too.

It just tickles me a little to think that so many people consider their superior senses must be at a constant state of calibrated perfection. It could not possibly be their imaginations being better at adapting to something new than they can control. It has to be the equipment breaking in! What kind of walking, instrument of audiophilic precision could they possibly be, with that amount of slop between their ears?

 

[Bucknekked]

Hey, but if these ultra perceptive people can imagine all of these changes, they really ought not leave nothing out. I wonder if they notice the difference of when the new electronics smell gets cooked out of their electronics too. I mean, surely their sense of smell must be killer too.

It just tickles me a little to think that so many people consider their superior senses must be at a constant state of calibrated perfection. It could not possibly be their imaginations being better at adapting to something new than they can control. It has to be the equipment breaking in! What kind of walking, instrument of audiophilic precision could they possibly be, with that amount of slop between their ears?

MrBoat
I feel a rant coming on so I will be brief. I think the previous poster just tried to give a lecture on soldering to someone who welds and solders for a living. I could think of a lot of topics I might try to lend you some instruction on at my peril, but, trying to tell you you don't understand soldering or welding, would not be on my list.

Pointing out that soldering doesn't involve "any electrical activity" is not only factually incorrect, its like saying the sky is blue. What heats the tip of the soldering iron? Electricity. The posters point was something else, but if you make silly statements, you're going to get silly followups.

MrBoat, the human part of the equation here is the 900lb gorilla in the room when it comes to all these micro audio discoveries around equipment. We are a big ol bag of squirmy goo that can take sound waves and turn them in to something called music inside our skulls. We can also take pure imagination and turn it in to "facts" by typing it in to a keyboard. And everything in between.

I'm starting to rant so I'm going out and having a nice leisurely lunch and will undoubtedly hear elevator music on the restaurant speakers. I will enjoy it without commenting to the staff on the tweeter deficiencies or the lack of chocolate in the bass.

 

[3db]

It just tickles me a little to think that so many people consider their superior senses must be at a constant state of calibrated perfection.

Becomes more calibrated with every Scotch I consume.

It could not possibly be their imaginations being better at adapting to something new than they can control. It has to be the equipment breaking in! What kind of walking, instrument of audiophilic precision could they possibly be, with that amount of slop between their ears?

I'll drink to that

 

[M Code]

In my Bose operation manual it says to operate the amplifier for 25 hours then one can enjoy its full, dynamics performance..

Just my $0.02...

 

[mtrycrafts]

In my Bose operation manual it says to operate the amplifier for 25 hours then one can enjoy its full, dynamics performance..

Just my $0.02...

I guess before that 25 hrs, it is unintelligible gibberish. Oh, the magic...

 

[Mikado463]

In my Bose operation manual it says to operate the amplifier for 25 hours then one can enjoy its full, dynamics performance..

Just my $0.02...

I laughing at the mere thought of 'Bose and Dynamic performance' being used in the same sentence !!

 

[PENG]

I guess before that 25 hrs, it is unintelligible gibberish. Oh, the magic...

They meant before you reach 25 hours you get about 99.9999% but not 100%/full.

 

[mtrycrafts]

They meant before you reach 25 hours you get about 99.9999% but not 100%/full.

Oh, my mistake. That is an astonishing level of hearing to distinguish that .0001%.
I guess they are the trained Harman panel then.