Break in period


I have just acquired the Conrad Johnson CT5 preamp and CJ LP70S power amp. Would appreciate inputs /advice of fellow a'goners regd optimal break in period and is the break in period dependent on playback volume or amount of
gain. The reason I ask is coz a Stereophile review of the CT5(July 2006 ?)mentioned that the preamp was left in continous play mode for a week, that translates to 150 hrs.Given that i listen max 2hrs/day and more on weekends, that translates to a break in period of nearly 2 1/2 months !!
Have huge issues leaving the system running 24/7 coz of erratic power supply and neighbour's privacy etc
Would appreciate any/all advice
Cheers
Convert?fit=crop&h=128&policy=eyjlehbpcnkioje1mdexodkxmzusimnhbgwiolsicmvhzcisimnvbnzlcnqixx0%3d&rotate=exif&signature=1d1d857e0c004706e924cc8c8bf58805a3900c7e880689f3fe8879f059607ee3&w=128sunnyboy1956
The last three pieces of CJ I owned did not make it to 150 hours. Forget break in, they all broke. Shipped back to Virginia at my expense.
if it sounds fine, don't worry about break in. critics have loaners for as long as some folks own components. cj always sounds great, broken in or not.
I would consult conrad johnson they know their equipment best. I have a premier 350ss amp with the teflon caps and break-in was long 250+ hours. I listened to music and did nothing special for break-in. Leaving tube equipment on unattended 24/7 to me makes no sense and can be dangerous. If the equipment has a stand-by mode then I would utilize that function but I would not leave it fully powered up unattended. Just my thoughts

Chuck
Tubes don't "break in" but may change slightly as they age. Everything does.
Most components require some break in. Film capacitors will break-in over 100 to 400 hours. Resistors, tubes and the cabling will also break-in or settle as they are exposed to current.

I wouldn’t worry too much about it, just run the amps and enjoy. You’ll notice a slight improvement as the components settle in – no big deal. I wouldn’t bother leaving gear on 24/7.

Regards
Paul
The CT5 will take at least 400 hours for it to sound its best. The folks at cj will say 200 hours, but both the dealer's and my experience showed it to be longer. It is true that it will start to sound better at 200 but the best is yet to come.
advice of fellow a'goners regd optimal break in period and is the break in period dependent on playback volume or amount of
gain.

I will re-iterate what I normally say to these threads; well designed audio electronics equipment and cables should NOT drift significantly (i.e. audibly) between the time you plug it in and a few hundred hours. Of course, things age with time, heat, stress etc. but useful product lives are usually measured in numbers of years...

As to reported vast differences after a few hundred hours => either this is perception as the ears/brain are more familiar with the "sound" (it is well known that musical hearing ability can be improved with training/repetition) or it implies a badly designed piece of gear...(linearity, stability and reliability of ouput signal over time is a primary requirement of an audio product)
Cycling on and off actually helps to form the electrolytic in the power capacitors. I have never had any problems as a result of turning off equipment when finished listening to it. This on/off fear thing is way out of control. Save electricity, reduce the chances that something will hit the power grid and fry your stuff, and turn your gear off when left unattended.
"I will re-iterate what I normally say to these threads; well designed audio electronics equipment and cables should NOT drift significantly (i.e. audibly)
between the time you plug it in and a few hundred hours."

laudable belief. Unfortunately reality is impervious to our wishes, beliefs, opinions or otherwise. Things either are or are not, regardless of what we believe they 'should' truly be. I have no beliefs on the subject, but only modest experience with just a few components. My ARC Ref 3 improved dramatically from 0 to 150 hrs, significantly up to 400 hrs, and subtly up to 550 HRS; its 6550 rectifier tube started to deteriorate at approx 1300 hrs and I replaced it at 1900 hrs; its replacement stabilized at 70 or 80 hrs. My X-01 Limited became listenable only after 200 hrs, was quite good at about 400 hrs, excellent at about 800, but kept improving subtly until about 1200 hrs. Different equipment may behave differently. . . or even worse, I may be totally delusional.
Buy some cheap output tubes and run the system a lot, not continuously. Keep the cheap tubes for emergencies later. For $50 to $100 bucks, you will get a piece of mind.
Guidocorona,

laudable belief. Unfortunately reality is impervious to our wishes, beliefs, opinions or otherwise. Things either are or are not, regardless of what we believe they 'should' truly be

IMHO, in reality, one can select high quality electronics equipment that does not drift measurably or audibly in as little as a few hundred hours; equipment that can function accurately from day one and for many years.

Laudable make believe perhaps but I honestly think this is attainable from many respectable electronics manufacturers.
"IMHO, in reality, one can select high quality electronics equipment that does not drift measurably or audibly in as little as a few hundred hours; equipment that can function accurately from day one and for many years."

Break-in has nothing to do with the quality of components. I have used TFTF V-caps on a few amps and noticed how they change during break-in. Care to name a better foil capacitor than a V-Cap?
Hi Sunny,
I'm sorry I can't offer any help but I own the CJ Premier 11a-17LS combo and have been wondering how significant a step up the new CJs are. Have you listened to any of the older stuff? I hear the new gear if faster which would be good for my JM Labs.
The reason this preamp takes so long to break in is because of its teflon caps. You wouldn't believe how much better this thing will sound, compared to the way it does now (which probably isn't too bad). But teflon caps take time, and there's no way around it. Same as my Premier 17LS2. It's worth the wait. The people who haven't experienced this don't know what they're talking about. Good luck, Dave

PS The break-in with teflon caps is not linear. Don't be surprised if it yo-yos back and forth a bit. My Ack dAck 2.0 with the teflon option just about drove me nuts before it finally settled down. That one took a good 200 hours.
No need to worry about the neighbors. The gear doesn't have to be played very loud to achieve the burn-in needed...usually around 200 hours.

I wouldn't leave tube gear unattended, but I do leave it on during the night, while I sleep when I'm breaking it in.

People who don't believe in break-in of gear are the same people who don't believe cables make any difference or that they need current to settle. They do...and it's usually around 200 hours to achieve 90%.

Speakers benefit from wide dynamic and volume swings. Everything else just needs current. The problem with tube gear is that the tubes can begin to short and if you aren't around to notice the "pops" then you could destroy your speakers or take out an amp.
Sunnyboy1956, I can understand your impatience for break-in but just enjoy the journey and the music. Many manufacturers are strongly against leaving tube gear on 24/7 as it will lead to premature tube failure (quality tubes are not cheap) which in turn could result in other problems. Look at it this way, your patience will have its rewards. The very act of turning the gear on for a few hours with different types of music & volume levels, then turning it off may contribute more to proper break-in then continous operation, no doubt a safer route with tubes.
maybe my next audio investment should be an hour-meter! ;-)
"My ARC Ref 3 improved dramatically from 0 to 150 hrs, significantly up to 400 hrs, and subtly up to 550 HRS;"

While I don't have a REF 3... my LS-26 is tracking quite close to the REF in terms of sonic improvement.

I left it on continuously for the first 120 hours or so... then began powering it off at night. I do agree that power cycling components helps the break in process... at least in my experience.
Many thanks for taking the time and the effort to respond.I guess I am going to do nothing special apart from savoring some good/great single malt and let the CJs gradually overwhelm me. I began a complete revamp of my system in Sept 2006 with the CJs being the latest entrant(6 days old as of today).I guess there is a multiple break in underway,since the Cardas Gold Ref speaker cables are also barely 2 weeks old.
I confess the decision to plunge for the CJ gear was not based on actual listening/comparisons given the limited availability of brands in India. It was largely prompted by perceived compatability with the rest of my gear and the desire to build an all tube/ESL system. ie MF kw 25 DAC & transport,Quad ESL 2905s speakers. In a sense the system is largely based on the July 2006 Stereophile which had great reviews of all these components.
The system looks and sounds incredible and the prospect that the sonics can only improve is enough to keep me smiling!!
Many thanks and happy listening.
The bottom line is if you like sound out of box than you don't need to worry about break-in.
Sunnyboy1956

Great system! Enjoy the music and the single malt because in the end that is what it is all about.

Chuck
After reading this thread I am surprised that there are still those out there that adhere to the idea that break-in does not exist.

Some years back we looked into the phenomena to try to figure out what was going on. As a manufacturer I can tell you that we hear break-in all the time- the question was what was causing it. Here's what we found:

built up, one of our units has specific power supply voltages. After break-in (6 months), the unregulated power supplies will measure slightly higher. So something in the power supplies gets more efficient. The appearance is two-fold: filter caps seem to operate more efficiently, although they are 'formed' at the factory. However after break-in the current inrush at turn-on is lower! The other appearance is the transformers themselves, which have substantial lengths of copper wire in them- which has a measureable break-in: lower resistance.

Resistors do not appear to break-in.

Film caps do! -and their qualities in this regard vary according to dielectric and manufacturer. Oddly, we have seen a lot of comments about the V-Cap Teflon (probably the best coupling cap out there right now) breaking in, but we do not find that there is a break-in with it of any significance, which seems to be common with other Teflons we've used. What *does* seem to happen is that the installation of the part can disturb other elements and the part itself is so transparent that it reveals that easily.

Wire does seem to break-in. Copper in particular- silver does too but is much faster break-in, although they both ultimately arrive at the same place if the silver is pure and the copper is pure, and both are installed with correct attention to details of use specific to each.

In all cases, the results are measurable and audible, in this way confirming their reality and not some sort of myth.
Break-in has nothing to do with the quality of components

I have nothing more I can say to those who claim dramatic audible break-in changes, which can drive people nearly nuts, have nothing to do with the design "quality" of components; I beg to differ on what constitutes "quality" that's all.
Tube components take much less to warm up and or break in opposed to solid state.. However the real problem is not the topology used its the Capacitors.. The super tight teflon whiz bang Caps take some time to open up.. The oil caps take a little less, in between cheap caps are somewhere between those two on time to sound right... But all caps seem to be a little better with some age on them. Wire, Resistors etc.. Especially Tubes "Burning in" is more or less B.S. Although Can agree with above tubes can change character and smooth out with a few hours on them.
By the way this is just my own opinion on testing the waters and following things after changing out and modifying components.. Mostly it seems to lay claim for true when Speaker drivers or capacitors are involved, they do change and sound better with time.
Shadorne, could you tell us what you mean by 'quality of components', and could you give us some actual examples of high end gear you personally experience did not benefit from break in?
hi marakanetz:

it sometimes happens that the sound of a component changes with time in such a manner that you prefer its presentation before it has received a signal, in comparison to its presentation after it has 100 + hours.

i have experienced both improvement and degredation, following "break-in".

be careful. do not judge a component too soon, especially during a home audition.

another way of looking at "break-in" is as establishing a link between components. as an example, consider interconnect cables. when a cable interfaces a cd player and a preamp. a link is established between three components. if the link is broken after the cable has 100+ hours and the cable is placed between a second cd player and preamp, it may be necessary to establish a new link by running a signal between the cable and the "new" components.
could you tell us what you mean by 'quality of components'

Obviously there are many things that define quality and this may differ from person to person as to what they are looking for (THD+N, TIM, Channel Separation, power, headroom, etc.). I simply included reliability and consistency of response over time as a factor that I regard as one of the important qualities in an audio component. A tube that changes response over a short time of a few hundred hours and ultimately dies shortly after that, is not the kind of quality I would be satisfied with. Others may be happy to put up with these issues and lack of consistency in sound in order to benefit from the fantastic sound of a particular finicky tube. Their definition of high quality differs from mine that's all (weighted to what they perceive as the "best sounding tube")

The list of components that do not audibly drift in a dramatic way with time is far too long for me to mention. Of course, components do age and they do fail but often they last a good many years. A small drift in power supplies as equipment ages is also well known (which is why components are generally designed to operate accurately within a tolerance range).
Thank you Shadorne, I understand of course that superstable high end devices whose sound is largely optimized out of the box are likely in the hundreds, or perhaps even in the thousands, and that this is not the place and time for an exhaustive list. Unfortunately, I have not had the luck of finding even one of these marvels yet in my admittedly limited experience. Perhaps you would care to enlighten us with just 5 or 10 of the most well known and respected examples.
Perhaps you would care to enlighten us with just 5 or 10 of the most well known and respected examples.

If I gave you well known names from respected engineering and manufacturering bands like Sony, Denon, Pioneer, and Yamaha would this help? Since it is not that difficult to design stable and reliable audio electronics these days then there is really no "enlightenment" to be had.
Thank you Shadorne for the enlightenment. I am a little surprised about your findings. Yet Admittedly, I have not had in depth experience with the mainstream commercial audio brands over the last couple of decades, But I recall that just a few years ago, even the perfectly respectable stereo in my Toyota van took perhaps 200 hours to sweeten up. Regardless, now I keep track of changing behavior of any new piece of audio gear through a spreadsheet. Next time I have the opportunity of examining a device from a major electronic manufacturer, I will track any subjective changes--or lack there of--over time and may be able to form a more informed understanding of the matter.
03-11-07: Shadorne
If I gave you well known names from respected engineering and manufacturering bands like Sony, Denon, Pioneer, and Yamaha would this help? Since it is not that difficult to design stable and reliable audio electronics these days then there is really no "enlightenment" to be had.

Yamaha, Sony, Denon, Pioneer.....do these guys use the same quality parts as say ARC?
Do you exclude the possibility that, say, TRT capacitors used in Audio Research, actually do change sound during the break in period?
I had an ARC LS-15 preamplifier where new caps(TRT Dynamicaps) were installed and I noticed siginificant improvement in sound only after 75 hours. I listened to it for the first 3 or 4 hours, didn't like it at all, but made notes. Turned the amp off and ran a signal from the tuner through the preamp for the next 70+ hours without listening. At about 75 hours I listened again and the sound was totally different. Way better than the way the brand new caps sounded and much better than the original ones that were replaced(REL). So possibility of me getting used to the sound is out of the way. If it is not break in that helped, what is it then?
Yamaha, Sony, Denon, Pioneer.....do these guys use the same quality parts as say ARC?

They make designs mostly using transistors. The pre-amp you refer to uses tubes. The quality of the individual parts cannot be directly compared as the designs are quite different. Tube preamps run at much higher voltages and need higher quality (rated) components.
Shadorne, your last post got me thinking. . . what could possibly explain the 1200 hrs to complete break in for my TEAC X-01 Limited CDP? Perhaps Crypto-tubes. . . really tiny. . . really well hidden. . . perhaps kept secret by TEAC. . . real conspiratorial like? Or is it just a truly badd bad kind-a-hopeless solid state design cobbled together from bargain-basement parts. . . perhaps just one of them multi-K$$$ attractive boat-anchors which got foisted onto the financial shoulders of this poor audiofool? I should get rid of it ASAP. . . now that I think of it, I should dunk my Toyota van too, after all its all-solid-state stereo took about 200 hours to sound decent as well!
Shadorne, I just don't follow what you are saying.
Guidocorona,

I gave you a few brand names of a few consistent sounding, respected engineering and manufacturing firms (mass produced) that are well known reliable products. If, as you say yourself, your gear changes response or requires an extensive break-in of over 200 and up to 1200 hours then that would not be my preferred choice that's all. However, I don't agree nor would I dare suggest that your fantastic gear are just useless boat anchors or that you should dump your truck because of this. Peace. We probably have different interpretations of the differences heard from repeated playing of music. (what I call getting habituated or new insights from repetitive playing of music may actually all be "break-in", certainly I believe that ears/brain can be trained to become more discerning and repetition is a big part of it - so the listening experience is never identical)
Psychosomatic, huh? Or in other words. . . delusional, eh? And I thought that in 50 years of music I had reached a small modicum of insight. . . now I am really staggered by the harsh impact of factual reality!
Shadorne, are you saying IOW that you hear changes but you attribute them to yourself rather than the gear?
Has anybody measured new components with, say a spectrum analyzer or similar device(s), and measured it again after break-in and published the results? If the results are audible, shouldn't they also be measurable (all other things being equal - easier said than done, of course)? Jeff
Measuring break-in is not necessarily going to be very straightforward. You have to know what to look for. The basics don't change much. A lot of the obvious parameters measure the same before/after. That doesn't mean something hasn't changed. As Atmasphere mentioned, the best way to judge is by using your ears. It is quite apparent the change in many components.

The question is, what to look for? Let's take cables as an example. There is more than just RLGC parameters. Maybe the dissipation factor of the dielectric changes. Perhaps there is some contamination, impurity, or flaw in the refining or construction. I would look for the little things, like photoelectric, pyroelectric, thermocouple, electro-chemical processes, parasitic diode structures, etc. Copper-oxide is a semiconductor. It makes for a lousy diode. Dissimilar metals, junctions, crimps, solders, the list goes on. Could there be parasitic batteries embedded in a cable?

Note also, when a component undergoes manufacturing, it experiences many traumatic and often life changing events. Materials get melted, alloyed, refined, drawn, hammered, cast, extruded, gassed, separated, cooled, well you get the idea. Where exactly does the manufacturing process end? When the item has left the factory? Or when it has been conditioned and formatted for the application?

Examples? How about a battery? At least with NiMH and NiCd, you have to format them with an initial charge of 20+ hours. Really trickle it. If cut short, the result was a battery that would from then on hold much less charge. We did this test at Nokia, and a fully formed battery ended up with double the capacity. How about shoes? Don't they take a little time to break in? How about a violin? If a Stradivarius isn't played it loses its tone.

It might take more than a spectrum analyzer. But the answers are out there.

jh
Jeff sez
If the results are audible, shouldn't they also be measurable
Should be, I guess. BUT what would one measure? Once measured a diy phono equaliser with a friend (for other purposes) at ~2month intervals with a scope. Zilch.

Note however, that the caps had already been "treated" with a variac before they were mounted. Likewise with critical path resistors (components are important for the equalisation curve). Also, first measurement was well after first power up (a couple of hours or so).
Atmasphere,

Shadorne, are you saying IOW that you hear changes but you attribute them to yourself rather than the gear?

Often yes. Depending on the last time I had a cold the changes can be significant. Most often it is the result of focusing on something specific or different in a familiar repeated track. I suspect we get very accustomed to sounds and have a pretty good sonic memory (for example an actor's voice is instantly recognizable on a cartoon)...so changing a component as significant as a speaker can be quite disconcerting for several weeks as memory adjusts to the new way it sounds (versus previous familiar sound).

For example, when I upgraded mains from ATC 20's to ATC 100's I actually had to make an adjustment to the reduction in harmonic distortion in the extreme LF at higher SPL levels. Initially, it was disconcerting to me that a great big box speaker seemed to have less bass (but incredible clarity & punch) compared to a modest sized bookshelf with already a lean bass sound (compared to most fare). On the face of it, I had become accustomed to more bass warmth or harmonic distortion of the little driver when it was driven hard at higher SPL. (This effect cannot have been break in as the 100's were already well used).
when I upgraded mains from ATC 20's to ATC 100's I actually had to make an adjustment to the reduction in harmonic distortion in the extreme LF at higher SPL levels.

ATC 100 have less harmonic distortion at LF at high SP levels than ATC 20? Really

Did you measure distortion levels and how do you know it is harmonic distortions?
Did you measure distortion levels and how do you know it is harmonic distortions?

I did not make measurements but harmonic distortion is quite easily recognized for its warmth, woody or resonant sound.

I doubt ATC would make a more expensive big box speaker used in studio mix and mastering with higher distortion at "loud" SPL levels as a modest ATC book shelf near-field.

I could be wrong though. Neither speaker sounded harsh ( telltale signs of excessive odd harmonics ) except at excessive SPL levels that were beyond rock concert levels.

All speakers introduce lots of distortion. Given similar quality in design/drivers, bigger speakers tend to play louder cleaner (a general rule for all speakers and not just ATC).
Pauly
Did you measure distortion levels and how do you know it is harmonic distortions
Actually there is -or used to be- some ATC measurements available s/where re, linear & nonlinear distortion on their models. Unfortunately haven't found it-sorry. I do remember seeing this though... if you're actually interested.
Gregm,

I have a very old pdf of a paper that Billy Woodman published which explains his driver construction philosophy. It includes plots of speaker distortion and discusses IMD distortion and the advatanges of active versus passive designs. Unfortunately, speaker distortion measurements are pretty sobering stuff - I doubt most audiophiles realize the relative amounts of distortion coming from speakers compared to the rest of their gear. (Certainly not those who spend $4 K on speaker cables and an amplfier and only $1 K on speakers.)
Yes, Shadorne, I have always wondered how people can hear the difference between 0.002% THD on SS amps and 3% 'natural' harmonic distortion on tube amps over speakers with some 5-10% THD and sometimes up to 100% when the speaker 'doubles'! Methinks that they are hearing differences due to frequency response differences which are quite discernable even over 10%THD of the speakers.
Salut, Bob P.
Methinks that they are hearing differences due to frequency response differences which are quite discernable even over 10%THD of the speakers.
Salut, Bob P.

Agreed. I expect you are referring to the higher output impedance of a tube (with ouput transformer) coupled with a typical bumpy speaker load. This results in a different frequency response/presentation from a tube/speaker combo versus an SS/Speaker combo.
Shadorne -- that mustn't be what I'm referring to. I distinctly remember them comparing distortion figures (3%) I think between two ATC models at specific spl levels...Oh well.

the higher output impedance of a tube (with ouput transformer) coupled with a typical bumpy speaker load. This results in a different frequency response/presentation from a tube/speaker combo versus an SS/Speaker combo
Normally, yes. But one thing that is important in a spkr -- and one thing we do NOT know -- is the strength of each driver's magnet. A very "strong" driver (e.g. a Lowther, etc) paired with a SS will be overdamped and sound like Donald Duck unless tamed (i.e. at xover level). A hi output impedance paired to a very strong (i.e. electrically damped) driver may provide the optimum marriage...
Gregm,

IMHO, although high damping factors is a "pushed" feature of SS amps....I think it is really over rated.

Frankly the driver Qes and Qms coupled with the box design almost entirely dominates driver response...above a damping factor of about 5 a higher damping factor really makes almost negligable difference to the driver response, as the voice coil and magnet size dominate the driver electrical damping. (A good speaker design should be as close to critically damped as can be achieved given a host of other compromises)

I suspect most differences heard with low damping factors are more related to frequency presentation, as a high output imepdance device acts as a filter when coupled with a variable load (speaker)....
After retubing of the PH5 with 4 matched 6922EH (purchased directly from ARC) the magic of the PH5 sound is still there, but i had to turn up the volume several clicks on my ARC-LS26 to obtain gain comparable to the old tubes--matched with the VS55 -- i have now about 35 hours -- is that normal ? VASILI