Why I Rarely Re-Cap My Vintage Receivers

Gotcha. I have read about some sx-1250 filter caps blowing in glorious fashion causing damage. No pics here. I look at recapping as part of owning a vintage unit. I go through all of mine. I'll just bow out of this thread again. Best of luck guys!
Stick around - your input is always welcome.
 
This is not any kind of insult or put-down. It's OK to like a certain sonic signature. Much of it is what you're used to, or what you remember from a different time. Sonic memory is notoriously unreliable. I remember how great Jefferson Starship sounded on my first girlfriends console system. No doubt if I could hear it today I'd be horrified at the ceramic cartridge plowing it's way through the grooves. I've also found that what my hearing likes today is way different than when I was in college. High frequencies, unless "just right" are way more annoying than they were back then.

The problem is that "wonderful" old sound isn't apt to last, the sonic illusion turning into flaming reality as those old parts give up the ghost. Also, be assured, it didn't sound that way when it was new, if that's what anybody thinks.

First girlfriends are often recalled when one hears music associated with that time and emotional state... usually one's youth. The music, the vocals, the lyrics, all get funneled through one's "emotional brain" or limbic system and emotional memories are some of the strongest/longest lasting memories we form. Those feelings/experiences get burned into our brains much like a brand on a cow. Whenever we revisit those, the emotions are triggered... even though the music might have been poorly played or reproduced on sub-par equipment. I think there's a lot of psychoacoustics going on in the recollection of music memories, as well as adjusting to a new set of speakers/receiver/audio hardware.

First/Second/Third girlfriends... a great way to recall audio!!
 
I gave a 40 year old PA100 100 wpc power amp to a friend of mine. He brought it in to replace the old 16 gauge power cord and caps. The technician looked at him kind of bewildered like and asked why. Both the cord and caps were fine. He said "I can change them, But it won't make any difference in sound quality".
 
Reading through here at what others have dealt with , I have had both positive and negative recapping experience. I had a 1964 Fender Bassman that had the best sag and feel of any guitar amp I've ever owned. After five years and hundreds of gigs the caps in the power section began failing. After replacing them the amp became became very cold sounding with no feel and super quick note decay. From sublime to useless.
On the other hand I had two failed leaked out caps in a Marantz 1030 changed to 1 percent caps along with rest that hadn't failed and the amp became a different beast. Complex midrange, fat bass, fatigue free top end, in short perfect. Incredible improvement to become my favorite piece of hi fi gear ever. Later a cap replaced 2240 gave me almost identical sound to the 1030 but with more muscle, and fantastic bottom end. So I guess it depends on the piece being fixed and perhaps there is a bit of luck creating a perfect tonal balance between certain parts in certain amp sections. Sometimes it seems that part specs don't guarantee an actual up scale improvement. The comments throughout this thread seem to bear this out.
 
That's the problem with guitar amps. Because distortion is a big part of an amps signature sound, and old caps seem to contribute to that. Guitar players are often shocked when a recapped amp sounds different. Thing is, it's now sounding like it did when it was new. Heard the same thing with certain Marantz receivers. People come to like the sound of a failing amplifier.
 
Some of you may know that I have a weakness for vintage stereo receivers, particularly Technics, Sony, Pioneer and Kenwood....In all I have over sixty units now, most in various states of disrepair...Perhaps fifteen are running now and I cycle them through and "blow the carburetor" out on all of them once in awhile to keep em thumpin. What I rarely do, however is recap. And I should add the average age of my typical receiver is approaching 40 years of age.

I don't recap for several reasons...First, I am a firm believer in the synergy of having all components mature together. I remember about five years ago I came into a beautiful Sony STR-6036A, an amazing unit whose output far exceeded the sticker 15 watts. Anyway, I had joined another forum and the consensus seemed to be that anything and everything should be recapped willy nilly if over thirty years old...wow! How exciting! I was gonna have a chance to have at all my gear and recap til the cows came home. I started with the Sony....my beautiful classic Sony. I gathered the caps and one fine day I popped on my apron, wielded the desoldering iron and, in three hours, changed out every electrolytic on the boards...

Sadly, when I brought the unit up slowly on the variac I was shocked at how the tone had changed! About 20% of the midrange just disappeared! I could have cried...hell, I think I did cry! And you know the saddest part is that there was nothing wrong with the caps I changed out...not a one of them...Sony used great stuff and those were the days when caps were quality, quality, quality.

You know my bottom line is that electronic gear acquires an audio patina just like fine furniture, beautiful coins, and antiques in general....Finagling with replacing components just because they may have some age is just senseless...look at them first...really look at them...I can guarantee you that 95% + of them will look great, if not all...

My Sony never sounded the same again but I never had another recap festival again..and all my equipment has held up beautifully! Just because you have a nice piece of vintage gear does not mean it should be recapped....the old saying that to a man with a hammer, everything looks like a nail, is very appropriate here...to an audiophile with the recapping urge, everything looks like a chance to use the desoldering and soldering iron...I encourage you to resist the urge...once the patina of sound is gone, it can not be brought back...
In closing I should mention that I have done plenty of repair jobs for people who recapped units only to have trimmed leads carelessly fall down into the unit and short out components on the board...be careful, use a variac, and check after every changeout...you won't have the woe is me..what did I do wrong regrets...

Just my two cents....love to hear yours and Happy New Year!

Rosie :music:

I feel your pain, we have a two different receivers one is 30 yrs the other near 40yrs old have been considering the same thing. Talking to those in the repair business have said hold off wait till I start hearing not normal things. I do have a 70 yr old Heathkit power amp that is getting a recap it started to smoke at only 40 volts on the Variac that was a sickening moment.

Mike
 
I recently repaired and recapped a Marantz 2330B for a friend. He bought it used and wanted it for a spare but said one channel didn't sound quite right. The caps in the pic were in the preamp section... He says it sounds better than his other 2330B and wants me to upgrade it soon.
 

Attachments

  • 11992188_10206922976046790_1359617283_n.jpg
    11992188_10206922976046790_1359617283_n.jpg
    36.6 KB · Views: 62
Some caps that were working well when this thread was started will by now need to be replaced.
So far nothing's happened here at Chez Loopstick. Are you just saying that out of the billions and billions of capacitors in existence there will have been some non-zero number of failures during the past five years? The typical problem with AK "debates" is that rarely does any sense of scale get introduced into the discussions.
  • Do cables matter? Yes! Cables have capacitance. Oh!
  • Do grain boundaries matter in copper? Yes! Grain boundaries introduce phase shifts. Oh!
  • Should I be concerned about skin effect in cables? Yes! It affects high frequencies. Oh!
  • Does digital sound worse than analog? Yes! Digital is all ones and zeros. Oh!
  • Should I do a recap? Yes! Capacitors fail. Oh!
  • Should I use a distribution amp with my FM antenna? No! They introduce noise. Oh!
  • ..., etc., etc., etc.
I've heard many other unquantified "platitudes" but these are the ones I can remember at the moment.
 
My comment was a quip, partly about the age of the thread, but I am speaking from experience. I've restored at least 25 amps or receivers in the last 10 years, mostly tube units. Nearly all have had aged or dried out caps that have to be replaced to get the unit to work correctly. If you are asking for numbers, only 1 out of the 25 worked well without some/all cap replacement, especially the high voltage electrolytics. Some worked a bit; many did not work at all.

My most recent experience was with a NAD 7020 that I wanted to use at work. One FM stereo channel was down. The problem turned out to be one faulty cap. But there was no good reason why that one failed, and much of the original soldering was bad, so I recapped the whole receiver. All the other caps tested okay, but now it works correctly and I can be pretty sure I won't have to open it up next week/month/year.
 
Cable capacitance does matter if used with

1. A phono that has a magnetic cartridge.

2. Sources with a high impedance feeding a high impedance input.

Concerning the capacitors, at one point there was an electrolyte formula being used that wasn't very good. A lot of computer motherboards were affected by caps that failed early. Could perhaps be why some of the caps aren't lasting as long in other newer gear as well.
 
What kind of numbers?

Common sense should tell you that you wouldn't want a high capacitance cable connecting an FM tuner with 250K output impedance into an amp with 250K input impedance as that would reduced the treble some.
 
Back
Top Bottom