Got myself a Yamaha CA-1000

asdf_x2

Active Member
For a while now, i've been wanting to try out a Yamaha CA-series integrated. I missed out on a local reasonably priced CA-1010, probably only by few minutes. As a consolation i bought a CA-1000 from german epay for not too much money:
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It works but some has been inside doing dodgy stuff.
For example destroying solder pads and lifting few on function board. On left main amp board looks like a probe slip and as a result some charring around TP4.

Following components have been changed by clipping off the ones and soldering new ones to the old legs: TR602, TR603, R622, R630. While i measured R622, it broke off. I will replace all of these.
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I'm a bit confused since on the left side main amp's TR602 and 603 has the following text: a725 22G (-> 2sa725?). These are replacements.
And on the right side: 58 a763 WL 4B (-> 2sa763?). These look like they might be original or earlier replacements. At least they are not attached to any old legs.
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Service manual lists TR602,603 as "2sa572W-4,5".

On power board TR706 has been replaced with ? (see photo).
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Service manual lists it as "2sa572WL 4or5".
Should i replace these all with 2SA992?

Also there are no heat sinks on TR702,704 like i've seen in others' pics of CA-1000. It looks like there's never been any.
Should i add them?

The kind person also has cut off the green/yellow protective earth coming from schuko plug to the chassis. For what reason, i have no idea :dunno: I will reconnect it.
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Filter board has been bypassed by soldering the 3 incoming wires to the outgoing ones. As a result filter switches and muting isn't working. I'll leave this for the time being since i have no use for filters. Muting function i might use, so let's see.

I've ordered new caps, trimmer pots, Class A/B microswitches, relay and new flameproof metal film resistors to replace fusible ones.
Is there some other preventive maintenance that this unit should receive?

Despite all this, the unit sounds quite nice even though it hasn't been recapped yet. Especially Class A with headphones. There's something about it i can't describe except it feels like music comes alive in Class A. I'm so looking forward to hearing it after recap and the rest.
 

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nice one -- interesting when you open these old amps up isn't it? its like a lucky dip, or a box o' chocolates, a blind date....you never know what you'll get!!! nice work, and the ca-1000 is a nice amp. many, many of these can be had in Nippon...
 
I too like the Yamaha Class A setting. I have a 1983 A-1000 that has been re-capped that sure sounds good.I bet your Yamaha really will sound stronger when you are done with it. Wish I had the training to do my own repairs.... It has 10watts class A and 120 WPC. Class A use does make more heat vs AB and after 75/80 db on my speakers I really don't hear much difference at louder volume setting. Both modes are great but I have more bass at lower volume on Class A direct mode (no tone controls). These vintage Yamaha Natural Sound Class A,AB amps have that tube like warmth to them. My bucket list is a recapped/refurbished M80(30watts Class A,250 WPC AB) and C70/80 pre amp for vinyl and tape. A link I found on Yamaha amps http://legendaryamps.com/latest.html . I was looking for the Integrated models like ours here.:scratch2:
 
Full recap is certainly recommended if you intend to keep the amp. I had a 1010 fully recapped and it DID sound better. Tightened up the sloppy boomy bass and in class A was very sweet...

Sent from my XT925 using Tapatalk
 
I have a CA-1000 as well and it's been well used. Needs some work and I'll be putting it on the bench soon.

Good luck with yours!
 
Also there are no heat sinks on TR702,704 like i've seen in others' pics of CA-1000. It looks like there's never been any.
Should i add them?
If you can find some that will fit. It probably wouldn't hurt to sink them.
 
Nice.

Love the CA Natural Sound Integrateds. I have had a CA-810 since 1979..

Had a 1010 for a while. Hefty and well built.

I've tried to be a fan of Class A, but alas, my ears can not pick up any subtle difference from the transistors completing a full sine wave. Yet, It's nice to have the option!

Nice pics and detail. Fun thread. Thanks! and.... Congrats!
 
The CA-1000 was my first real piece of gear, one I still own since 1975 and cherish.
I'd love to send it to Iowa for a refurb:)
 
Good luck with the restore.

The CA-1000 was the Yamaha that made me like Yamaha.
Up until then....not so much.
I now have a CA-2010 along with a CR-1020 and CR-2020.

:music:
 
The CA-1000 was my first real piece of gear, one I still own since 1975 and cherish.
I'd love to send it to Iowa for a refurb:)

PM Avionic he does great work. I am sending him my A-1000 to have my MC phono stage repaired and have it serviced.
 
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Finally she's done! I did full recap including filter caps. And ended up replacing all 2sc458s and all 2sc1345s to ksc1845 in addition to the ones mentioned earlier. This cleaned up the sound a lot and made it more precise.

But i was left with occational quiet sizzling. It happened with pre decoupled and on both channels. From that i deducted that it was probably coming from transistors on the power board.

So i looked up replacements from other posts here and ended up replacing TR701-704. Out of those 2sc671 or 2sc1061 was the culprit. Changing them to TIP31 and TIP41 not only cured the sizzling but improved bass quite much indeed. So apparently the parts had trouble providing the needed power under load.

I did put heatsinks on them, but due to to component layout and size of the sinks i got, they are positioned a bit oddly. But i'm guessing it's still better than before?
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Phono was quieter on the right channel. I tried to adjust SEPP midpoints but they would adjust only up to 20V. This was before i changed the 1345's in there. Now it adjusts to 26,8V which is good enough for me (s.m. says it should be 27,5V). I doubt i'll hear the difference.

I also got isopropanol and for the first time cleaned the trace sides of the boards. They do look much better now.

After this it sounds very good. There's something special going on with this amp! To my ears its very detailed and dynamic without any irritation on highs. And bass has notes and texture!

Big thanks to AK and all who share their knowledge here! In the end i have a wonderful 40 old Classic singing beautifully in my living room!
 

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Very nice, great to see the pictures and hear of your success.

I'm not quite sure, because the picture is a little blurry, but your tr706 looks like a few of the transistors in my CT-800 tuner. If I recall, they are sort of shiny purple ball-like things.
 
Nice job on the CA!

I too have been working on a CA-1000 that started doing the sizzle and flickering of the power lamp. Sometimes tripping the relay.

Also suspected the transistors on the power supply board. Just haven't gotten around to replacing them. Was going to do them when doing other work. They tested out OK.

I needed to replace one of the speakers connection strips on the back pane, recapped and replaced the relay. Also replaced all the fuse resistors in the power supply and amplifiers.

Then after sitting for a week the sizzling started. So took out of service and will get to it sometime. The heavy units are giving me some trouble and don't want to push it. Not worth the trouble any more.

http://www.audiokarma.org/forums/showthread.php?t=557352&highlight=ca-1000

http://www.audiokarma.org/forums/showthread.php?t=494039&highlight=ca-1000

Barney
 
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Very nice, great to see the pictures and hear of your success.

I'm not quite sure, because the picture is a little blurry, but your tr706 looks like a few of the transistors in my CT-800 tuner. If I recall, they are sort of shiny purple ball-like things.

Yeah, that was a 2sa572 and i replaced it with 2sa992. Probably didn't need to. Solder looked original so i'm guessing that was original part.


For some reason i had two different pictures on my ipad in my last post. But now at work, there's 1 picture two times? I'll try and put the correct pics later on. For some reason i could upload only 1 picture to the post on the ipad?
 
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