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New find AR5


djcheung

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New caps do need to form, or if old reform. Thats what I understand anyway. Even the tech guy I use asked me if I was first forming the new caps I was installing in the speaker rebuilds.

Now I'm really confused.

der

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der,

This is just another one of those golden eared discussions with absolutely no measurable proof or resolution as it relates to sonic impact. Ken Kantor of AR and NHT fame commented in a long thread (in another forum) that caps take mere seconds to "burn in" upon initial use in the circuit...and the rest is in the mind.

I'm in his camp on the issue.

Roy

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I will ask my tech for his technical description about this and see what there is to it. Otherwise, what else could explain so many tales of folks saying things sounded better after a while? Something to so the drivers?

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Hi,

I like to put my .02¢

You have a very nice AR collection, and the AR-5 is quite rare. They didn't make lots of that model. It's one model I've been looking to get for a very long time.

After 15 or more years of searching and looking, I finally just got a nice pair of AR-91.

So there's hope for me yet to get the 5, soon I hope, I'm getting old :lol:

Did you ever think about veneering them. This is one of the AR model that deserve this. Squarish box, more or less, are very easy to veneer, just a thought.

André

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I have replaced a dozen cap sets or so, and the burn in period does seem brief. I wonder if they sound better and better after time is a measure of the listener's ears tuning into the new sound from the speakers.

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I will ask my tech for his technical description about this and see what there is to it. Otherwise, what else could explain so many tales of folks saying things sounded better after a while? Something to so the drivers?

Welcome to the world of golden ears and "audiophile" dogma. :)

It is the same explanation applicable to the claims of (often "dramatic") improvements made by:

-expensive replacement capacitors

-overpriced replacement resistors

-boutique cable and speaker wire

-by-pass caps

-high priced binding posts

Fantasy and conjecture using pseudo-scientific explanations keep things interesting. Think placebo....

Roy

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Good point, although I never mention this on AK. This topic has an habit of turning nasty . This is why I'll first listen to the refurbished 91, for a while, and maybe, replace/upgrade a few caps, and see what happen.

I like to believe it should make a difference with 35 years old speakers, but who knows. One thing for sure, I will not use Mundorf Supreme Silver Gold oil capacitors, if I decide to do it.

André

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Good point, although I never mention this on AK. This topic has an habit of turning nasty . This is why I'll first listen to the refurbished 91, for a while, and maybe, replace/upgrade a few caps, and see what happen.

I like to believe it should make a difference with 35 years old speakers, but who knows. One thing for sure, I will not use Mundorf Supreme Silver Gold oil capacitors, if I decide to do it.

André

I agree re: AK, Andre. I tuned out of those threads after watching unqualified "experts" argue these things with Ken. Hey, if something "sounds better" to someone, then it does. Those debates are useless to a person seeking practical speaker restoration advice, and they resolve nothing of technical significance.

On the other hand, original electrolytic capacitors do wear out, and it can be a prudent project to replace them with reasonably priced film caps or good quality npe's. A search of this forum will find references to Dayton, Erse, Carli, Bennic, Madisound surplus caps, Solen, and others in the same price range. All are more than good enough to help bring our old speakers as close as possible to original specifications. Larry/Vintage AR capacitor kits consist of Parts Express Daytons (5% type).

There are other variables to take into consideration, such as the performance of 35 year old drivers. Those limitations are likely to exceed the tolerances of any of the above mentioned capacitors.

Roy

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...Otherwise, what else could explain so many tales of folks saying things sounded better after a while? Something to so the drivers?

My belief is that your ears begin to get accustomed to the sound of the speaker, over a period of weeks. Some may attribute that acclimatisation to "burn-in" of components or whatever.

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Certainly most caps from the 1970's and beyond drift in value. I have rebuilt a couple of sets of AR crossovers with new caps and the difference is immediately apparent to me. On the other hand, I don't detect further improvement over time. I would say that I'm "used to" the sound of my 3a's - having listened to them almost exclusively since I bought them new in 1969.

Thanks for the replies, I think I fall into Roy's way of thinking on all this.

der

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Welcome to the world of golden ears and "audiophile" dogma. :)

Fantasy and conjecture using pseudo-scientific explanations keep things interesting. Think placebo....

Roy

Flat earth was scientific fact before someone was able to prove it otherwise...

I agree that selling dramatic improvements to audiophiles is profitable business. But this does not mean that different components do not have differences in their performance, like Carl did explain in his capacitor related tread. I am also leaning to quite conservative side here. I do not find any reason to replace 50uf electrolytic with film cap when restoring something with limited life expectancy. I also use low impedance electrolytic´s for power supply and audio grade electrolytic´s for coupling duties, when restoring amps etc, as they seems to work good enough for me, are economical to buy and usually do not need more space than originals. It would also be most impossible even try to find out which mix of components will produce best performance in something like Citation 17.

However, I do find that it is hard to explain how something will sound if only measurements and scientific facts are available. Loudspeakers seems to be the weakest link in the chain. Properly designed amplifiers do exhibit lower distortion, considerably flatter response, less phase shift, less power compression etc... if scientific facts and measurements are all we need, then it would mean that we can use any amp within power ratings and results would be the practically the same. We have to choose only correct speakers? I do not think so...

I agree that there must be quite much placebo and other unexplained effect in audio. At least my system seems to have good and bad days without any apparent reasons. Reasons may be noisy power line, flu, moon phase, argument with wife or reformed capacitors. By the way, Quad 34 does reform coupling electrolytic´s every time preamp is turned on using active earth in PSU.

It would also be fair to say that some of those propeller heads do have systems that do sound quite good. I truly hope that I will learn some day difference between reality and placebo....

Best Regards

Kimmo

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Flat earth was scientific fact before someone was able to prove it otherwise...

I agree that selling dramatic improvements to audiophiles is profitable business. But this does not mean that different components do not have differences in their performance, like Carl did explain in his capacitor related tread. I am also leaning to quite conservative side here. I do not find any reason to replace 50uf electrolytic with film cap when restoring something with limited life expectancy. I also use low impedance electrolytic´s for power supply and audio grade electrolytic´s for coupling duties, when restoring amps etc, as they seems to work good enough for me, are economical to buy and usually do not need more space than originals. It would also be most impossible even try to find out which mix of components will produce best performance in something like Citation 17.

However, I do find that it is hard to explain how something will sound if only measurements and scientific facts are available. Loudspeakers seems to be the weakest link in the chain. Properly designed amplifiers do exhibit lower distortion, considerably flatter response, less phase shift, less power compression etc... if scientific facts and measurements are all we need, then it would mean that we can use any amp within power ratings and results would be the practically the same. We have to choose only correct speakers? I do not think so...

I agree that there must be quite much placebo and other unexplained effect in audio. At least my system seems to have good and bad days without any apparent reasons. Reasons may be noisy power line, flu, moon phase, argument with wife or reformed capacitors. By the way, Quad 34 does reform coupling electrolytic´s every time preamp is turned on using active earth in PSU.

It would also be fair to say that some of those propeller heads do have systems that do sound quite good. I truly hope that I will learn some day difference between reality and placebo....

Best Regards

Kimmo

<<Flat earth was scientific fact before someone was able to prove it otherwise.>>

Very bad analogy, unless you are suggesting those clinging to audiophile dogma are the flat earthers. The burden of proof resides with the golden ears, not electrical engineers.

<<if scientific facts and measurements are all we need, then it would mean that we can use any amp within power ratings and results would be the practically the same. We have to choose only correct speakers? I do not think so>>

The comments I've made concern only those generally accepted audiophile myths regarding speaker parts, specifically as it pertains to repairing old speaker systems. Of course there are differences in audio equipment designs. We are not talking about that here.

<<my system seems to have good and bad days without any apparent reasons. Reasons may be noisy power line, flu, moon phase, argument with wife or reformed capacitors. By the way, Quad 34 does reform coupling electrolytic´s every time preamp is turned on using active earth in PSU.>>

My money is on the "argument with wife" option. Then again, I suppose it could be dark matter or Higgs bosons "burning in".

Roy

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  • 2 weeks later...
...

<<my system seems to have good and bad days without any apparent reasons. Reasons may be noisy power line, flu, moon phase, argument with wife or reformed capacitors. By the way, Quad 34 does reform coupling electrolytic´s every time preamp is turned on using active earth in PSU.>>

My money is on the "argument with wife" option. Then again, I suppose it could be dark matter or Higgs bosons "burning in".

Roy

I'll go with changes in barometric pressure and/or blood alcohol level :)

My SAE amp tanked two days ago -- time for a rebuild after forty years. Now that made a big difference in how the AR 5's sound as I'm having to drive them with an underpowered amp which cramps their style a bit.

I didn't noticed any burn-in differences on the Madisound surplus caps.

I am eager to see how this pair finishes out. Getting all the paint pigment out of the grain is very time consuming. I haven't worked myself up to doing a veneer project yet but it is very tempting and if time was no object ...

Roger

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I know what you mean Roger about veneering. I walked by rolls of various hardwood veneer yesterday when I stopped in the local Woodcraft store and the hair on the back of my neck kinda stood up. Some times it would seem smarter to go with new veneer rather than trying to make the old beat up and stained stuff new again. Probably faster too if you knew what you were doing.

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  • 4 weeks later...

Hi Gino

Good link for members in Europe. The Wichelt linen in 18 count "lambswool" is the material recommended in the AR-3a restoration booklet. On this side of the pond it's available from 123stitch.com http://www.123stitch.com/item/Wichelt-28-Ct-Lambswool-Linen-Needlework-Fabric-18x27/76-135Z

-Kent

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