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Post by sandawa on Oct 20, 2005 10:19:32 GMT 7
for the benefit of those hunting for good vintage amps, this discussion/showcase is for previous generation (older than 25 years) Yamaha amplifiers. i don't know if it's necessary to integrate the other Yamaha threads here, some of which i also started, but that's for the mods to decide. i'll start with the CA-1000III integrated amp. Lordfoo got a CA-1000 (manual can be downloaded from the Yamaha website) yesterday, which is the older brother of my unit. the CA-1000s are "vintage gems" if you'll monitor comments from members of the Audio Karma website. Axel Dahl of The Vintage Knob even paid tribute to both CA-1000 and CA-1000III (known as CA-1010 in the international market, including the US.) the basic difference of the two models is that the older is rated 80wpc while the newer at 100wpc. both models run 20wpc on class A, but my unit really gets warm (though not as hot as the Musical Fidelity class A amps - i've used A1 and A120) when the A switch is on. more info on these gems are available from Axel's website: www.thevintageknob.org/index.htmli'll have more vintage hifi photos (already over 200 in my files, target is at least 500 when uploaded) than Axel, however, when my Davao vintage hifi website is uploaded before the end of the year. in the meantime, dito muna. here are three photos of the CA-1000III: pogi na rin for a '70s truly vintage amp. the yellowish true birch wood cover has maintained its quality despite its age. without its shirt. my only complaint is that it doesn't use toroidal - but a hefty amp, over 20kgs, in weight. the DC-offset and bias trimmers are shown as the dirty white buttons on the two boards. while DC-offset adjustment is easy - get the numbers closer to 0 millivolt but not over 50 millivolts - the bias adjustments depend on the original setting used by the manufacturer. i only tinker with the bias when i felt there was a major drift, which is indicated by the amp getting too hot even at AB operation that may later trigger the amp's relay protection circuit to turn the unit off.
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Post by <-94dB on Oct 29, 2005 14:27:09 GMT 7
Nice amp. This reminds me of the CA-610 I had before but sold on eBay months ago. I don't know but I prefer the sound of my Sansui AU-x701 over any amplifier I currently have or will have.
One thing I can't help but notice is the CA-1000III design appears to be cramped with little ventilation based on your photos. I'm worried of the electrolytic capacitors sitting between the two heatsinks failing. Considering that the amp can be ran in Class A , it would be prudent to replace the caps with similar ones (Nichicon or Rubycons). Replacing the caps shouldn't affect DC offset or bias.
Is the amp originally 100V and being run with a 240V /120V auto transformer? This could explain why your CA-1000III gets really warm in particular the amp's transformer even when idle.
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Post by sandawa on Oct 29, 2005 16:39:09 GMT 7
thanks for the observation. it's currently using a 100volt transformer. true, it's hot with the class A switch on but i'm not worried considering i also have a Marantz Esotec that runs as hot on class A and as i said, it does not go hotter than MF's class A amps i've used. so far, no signs of caps drying up despite its age: roughly 30 years old.
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Post by <-94dB on Oct 30, 2005 8:18:34 GMT 7
When you said it's using a 100V transformer, did you mean you are using a 240V to 100V step down transformer? If yes then everything should be fine and ignore my rant below . Anyway, I've seen a lot of people buying 100V stuff from Japan and just running them with a 240V to 120V step down transformer. A 240V to 100V step down transformer is not as common as 240V to 120V ones. With the wrong transformer, the 100V equipment is operated around 10-20% higher voltage. On some rural areas the voltage can go as high as 250V. The capacitors and the rest of the components are most likely operated above their rated voltage and will fail eventually. In the end they will blame the 100V equipment.
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Lordfoo
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Post by Lordfoo on Oct 30, 2005 8:26:32 GMT 7
The CA1000 is my first vintage yamaha amp. (I have 2 Yamaha HTs, an RXV740 and the older RXV793). I acquired the ca1000 after i missed out on a sansui AUD 907FExtra. I was pleasantly surprised when I auditioned the unit i've been seeing at the pier shop for several months. Also I just acquired a Yamaha NS690 the wood work of which matched the CA1000 precisely. I said to myself, "hey, this would go well together. Look at the picture, the Class A switch is the third switch from the bottom left. As sir Sandawa says, it has lower specs than the CA1000III but is the original model. I've used it only for a short while and for my tastes, it lacks a little bass. I have to turn up the Bass tone control a little to compensate. But that's my personal taste. Mids and highs are very very good specially with the Natural Sound 690. A brod of mine prefers all the controls to be set at neutral. I havent opened the unit yet, my brother did peek and confirms that the amp is quite cramped inside. I surmised this when i hefted the unit and found it quite heavy for its size. It was even smaller than the sony VFET 4650 i got at the same time but is twice as heavy. Look at the back, A, B, C speaker outlets. would anyone know what will happen if i connected the three amp speaker connections to the three speaker connections and ran speakers a, b and c at the same time? You can't go wrong with the CA1000 or Ca1000iii. They're both great pieces of japanese audio history.
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Post by sandawa on Oct 30, 2005 8:49:21 GMT 7
hi <-94db,
true. a few months after i bought my first 100V gear - that was three years ago - i tested the current at home at various hours and you're correct. the 110V transformers go up as high as 125V at night when there wasn't much power usage in the neighborhood. i found out local transformers merely reduce by 50% the voltage input and that the ratings assume the input is constantly at 220V. that means if 250V comes in, the transformer would take half and feed the 100V equipment with 125V.
from that time on, i changed all my transformers to 100V and also tested various brands and found 100V Panther and Zebra comparatively okay with variance ranging from plus to minus 10%. until now, i still measure the current coming out from the mains and the transformers regularly considering i have over a dozen 100V amplifiers.
by the way i had one or two burnouts during my first year using 110V tranformers on 100V equipment. i also encountered a problem using an AVR hooked to an expensive Denon preamp (PRA-2000Z) whose voltage output drifted to 130V from its original 110V rating. had to change two expensive capacitors. thus, even using an AVR is not an assurance that the equipment is safe. the solution is weekly tests of the current from the mains and the transformers.
nice exchange of info since these are valuable inputs to those using 100V Japan-made hifi gear. BTW, on behalf of the other guys here, welcome to the forum. i hope you remain active in the discussions. we need guys like you here.
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Post by <-94dB on Oct 30, 2005 9:48:14 GMT 7
Sandawa,
Blame lordfoo for asking me to join this group ;D.
I am also a member of AK and using the joemango monicker.
I envy you guys with all the gears you are collecting. I am stuck with garage sales, eBay and thrift store. My other interest is vintage(70-80) audio restoration and design.
lordfoo,
Regarding your question about connecting the CA1000 a,b,c speaker outlets. The extra connection on the NS690 speaker is for tri-amp configuration, i.e. separate amps for the low, mid and high using an active crossover network. Your original plan won't gain you anything.
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Lordfoo
Audionut
Listen to be heard.
Posts: 225
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Post by Lordfoo on Oct 30, 2005 17:59:38 GMT 7
Hi Joe,
Welcome to the forum. I am glad you've joined up. Sir Sandawa is one of the stalwarts of this forum (and of Phil Audio.)
Off topic:
Salamat po sa advice re: realigned pier surplus japanese tuners. I haven't gotten around the realignment concern yet. I am sorely tempted to take the risk i.e. just listen to a unit (maybe the Pioneer TX8800II) and buy it to really see if these realigned tuners are good. I need three tuner units for three rooms now being constructed. I've got the speakers, i've got the CDPs (2 at least) but I aint got no tuner yet.
re: the speaker a, b and c using the same amp. heheh i guess i suspected that and was just making sure.
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narayan
Audionut
I am a peaceful soul
Posts: 234
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Post by narayan on Oct 30, 2005 19:09:58 GMT 7
Sandawa, Lordfoo, I still occasionally use a yammie cr2040 receiver the innards of which very closely resembled those of the ca1000/1010 pati na the genuine wood veneer top and side covers. it came out yata in 1979 as that period's totl receiver(120wpc) but got it pre-owned in 1981. so almost 25 yrs na rin ito. will post pics later
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Lordfoo
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Posts: 225
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Post by Lordfoo on Oct 30, 2005 21:06:33 GMT 7
Sir narayan,
If I had receivers, then I wouldn't need the tuners. Why do you think there are so few receivers at the pier surplus stores? Are the importers not bringing home the japanese surplus receivers also because of the tuner realignment problem?
Anyway, is it true that separates sound better than integrateds sound better than receivers sounds better than component/consoles?
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Post by <-94dB on Oct 31, 2005 14:38:59 GMT 7
lordfoo,
Just what I said before. Any tuner that is "re-calibrated" won't be as good as before re-calibration. Once you mess with the RF and IF section without the proper test equipment, you must live with FM distortion of at least 1-3% THD, a far cry from most tuners spec'ed from 0.01% to 0.1% THD. The FM discriminator is very sensitive to de-tuning and the ear is not the best tool for aligning.
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narayan
Audionut
I am a peaceful soul
Posts: 234
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Post by narayan on Nov 1, 2005 8:42:08 GMT 7
Sir narayan, If I had receivers, then I wouldn't need the tuners. Why do you think there are so few receivers at the pier surplus stores? Are the importers not bringing home the japanese surplus receivers also because of the tuner realignment problem? Anyway, is it true that separates sound better than integrateds sound better than receivers sounds better than component/consoles? maybe the tuner alignment problem really makes bringin in receivers not worthwhile commercially. also integrateds appear to be more popular even in japan unlike in the US. i dont see receivers in the nisi list generally speaking, i believe separates would sound superior to integrateds and so on because the designer can incorporate beefier and better power supply etc. , which could be compromised somewhat in a single box design. otherwise, that box will become inconveniently big and heavy, not counting the heat that will be generated
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Post by sandawa on Oct 28, 2006 7:45:23 GMT 7
Finally, the K-nisi list has included my Yamaha B-3 on its list. Now, I understand why it's special, outside of its looks. The thin sound I was hearing, many describe as musical or sweet, was due to VFET adjustments shifting from solid state to vacuum tube charateristics. Here's K-nisi's writeup about it: page.freett.com/knisi/b-3.html
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joey
Audionut
Posts: 88
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Post by joey on Oct 28, 2006 18:13:20 GMT 7
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