Accuphase C-280 Review (Preamplifier)

[NTTY]

All noise below 1kHz was gone !!! Seeing that saved me a lot of soldering recap work ...

Well done!

None of the measurements after cleaning the switch contact indicated that any recap may have been necessary.

The power of measurements to prevent customers from being ripped off

 

[VientoB]

Beware of the capacitor police.

 

[cay-uwe]

Well done!

Just saw, that you reacently measured a YAMAHA C-2 as well and I am happy to see that my measurements very well match yours. One could say not too much discrepancy between the two different serial numbers ... I was impressed about the very low level of hum which correlates also with your measurements. OK, enough OFF TOPIC ...

 

[MLAS]

They are selling recaps for no reason. This is a common problem, service techs pushing unneeded recaps on vintage gear is quite an industry.

Blanket capacitor replacement is a poor idea, unless you have specific aims. If the aim is spending money then OK. Cleaning volume controls and contacts is a good idea and is cheap.

This C280 preamp that @NTTY tested, do you think it could achieve the stratospheric performance with bad capacitors? Mains noise on this unit is 130dB down for example.

I have a number of tests on ASR of even older gear. None needed capacitor replacement. One classic Yamaha receiver I worked on recently was nearly destroyed by a blanket cap replacement. Most volume controls and contacts need to be cleaned. And the relays of course.

Regarding bargain, Accuphase doesn't come to mind. It wasn't mentioned as a bargain at any point. They are great devices though.

Most lytics need substituted after 25 years of service especially when operating in a hot environment. This German tech said all the small caps inside the enclosures lost their capacity.
The original lytics inside the C280 are now approx. 40 years old.
It is good news that this particular C280 didn't need a recap although I saw some blue BC caps.
I'm contemplating to buy a C280 in Germany where Accuphase sold very good. If I could score such a good example as this one I'll be very happy.

 

[MLAS]

4 days for few caps / cleaning, and 3500€?

That's pretty steep indeed.

 

[totti1965]

That is also my general expirience with refurbishment I have done for many older equipment and as you say one needs to investigate if replacements are required.

Lately I bought an YAMAHA B-2 amplifier and a YAMAHA C-2 preamplifier. Both were not working properly and the main issue have been switch contact problems.

When I measured the YAMAHA C-2 preamplifier at the condition in which I got it, a spectrum analysis as follows showed up.

View attachment 532423
When I saw that I tought a whole of recaps will be necessary. Anyhow I started cleaning the switch contacts first and got afterwards this result.

View attachment 532424
All noise below 1kHz was gone !!! Seeing that saved me a lot of soldering recap work ...

By the way, after fixing the switch contacts I got this frequency response.

View attachment 532425
None of the measurements after cleaning the switch contact indicated that any recap may have been necessary.
In all cases I measured both channels, red = right, blue = left.

It is an absolute great gear and that being over 50 years old ...

This is information of incredible value! Most appreciated. Thanks!!!

Let us see the measurements of the Yamaha B-2 also! Was it the pyramid? Perhaps @amirm can put it on the front page if the measurements are a bit more elaborated.

 

[MAB]

Most lytics need substituted after 25 years of service especially when operating in a hot environment. This German tech said all the small caps inside the enclosures lost their capacity.
The original lytics inside the C280 are now approx. 40 years old.
It is good news that this particular C280 didn't need a recap although I saw some blue BC caps.
I'm contemplating to buy a C280 in Germany where Accuphase sold very good. If I could score such a good example as this one I'll be very happy.

See some of my reviews of >40 year old gear.

"all the small caps inside the enclosures lost their capacity."

If they had, that is truly remarkable. Any time these type of hysterical statements are made from someone who is about to (over-) charge me 3500 moneys, I ask for evidence.

There are certainly examples of gear that needs most caps replaced. My old Braun Atelier gear for example, due to poor thermal management, substandard voltage and temperature rated caps, and the poorly ventilated case they were stuffed into. These Atelier models have systematic issues though. This Accuphase really not. And, it does look like some caps were replaced in the unit tested here. But certainly not a blanket recap.

 

[MAB]

4 days for few caps / cleaning, and 3500€?

For sure, it's a luxury job.

And to get benefits on gear as performant as this Accuphase you need perfect solder manufacturing, as good as Accuphase factory.

And you also need to ignore the inconvenient bathtub curve and the so-called infant mortality (aka ELF, early-life fails):

Which is why you don't see medical, military, aerospace, etc. blanket-recapping equipment. Caps have large ELF rates that require additional pre-assembly testing and quality assurance if you want the ELF risk to be less than the wear-out rate.

And my experience with the audio-recapping industry is that most gear is not done expertly. I've posted a few examples of repair-bench train-accidents, like this classic Yamaha receiver with new caps that broke the PCB due to the new caps being different size and not adequately supported.

The bathtub curve is from electronic reliability handbook MIL-HDBK-338B.

 

[MAB]

I everyone, please excuse my bad English. I'm the friend of Florent alias NTTY. I just want to say publicly many thank's to Florent for the job he done.
I know that is a lot of work. Of course I said to Florent you've got free hands to push the measurements, because if not it won't be funny.
About this fabulous C-280 I can say that it work and match perfectly with is cousin the P-500. The conclusion is that this piece of art for me is probably
the end of the game. It's a little bit sad, but I follow testing some gears which have interest for me. In terms of ratio price/quality/performances/pleasure it's for sure
the best investment I've done.

You make me want to buy this:

 

[cay-uwe]

Let us see the measurements of the Yamaha B-2 also!

Thanks and I may open a new thread for my measurements of the YAMAHA B-2 amplifier and the YAMAHA C-2 preamplifier.

 

[MAB]

Thanks and I may open a new thread for my measurements of the YAMAHA B-2 amplifier and the YAMAHA C-2 preamplifier.

I encourage you!

I've tested a few old Yamaha pieces. Feel free to check out these links, or my about page...
Yamaha NS-18
Yamaha CR-1020

It's really refreshing to see these old gear perform really well. Even if the old speakers were sometimes an adventure.

 

[MLAS]

This is information of incredible value! Most appreciated. Thanks!!!

Let us see the measurements of the Yamaha B-2 also! Was it the pyramid? Perhaps @amirm can put it on the front page if the measurements are a bit more elaborated.

The pyramid was the B6. Same kind of amp like the Carver cube.

 

[MLAS]

For sure, it's a luxury job.

And to get benefits on gear as performant as this Accuphase you need perfect solder manufacturing, as good as Accuphase factory.

And you also need to ignore the inconvenient bathtub curve and the so-called infant mortality (aka ELF, early-life fails):
View attachment 532502
Which is why you don't see medical, military, aerospace, etc. blanket-recapping equipment. Caps have large ELF rates that require additional pre-assembly testing and quality assurance if you want the ELF risk to be less than the wear-out rate.

And my experience with the audio-recapping industry is that most gear is not done expertly. I've posted a few examples of repair-bench train-accidents, like this classic Yamaha receiver with new caps that broke the PCB due to the new caps being different size and not adequately supported.
View attachment 532504

View attachment 532505

The bathtub curve is from electronic reliability handbook MIL-HDBK-338B.

These are power filter caps seems to me to big and heavy for the PCB.
Done by an amateur.

The American amps that I have are all screw attached and with a supporting clamp on the bottom of the chassis.

 

[MLAS]

Have had the C2 and C2a preamps with the M2 amp. Great set when Yamaha made great stuff.

Thanks and I may open a new thread for my measurements of the YAMAHA B-2 amplifier and the YAMAHA C-2 preamplifier.

 

[MLAS]

Krell preamps were "famous" for their small caps. Or they dried out Roedersteins, or even worse leaked blue Spragues.

 

[NTTY]

For sure, it's a luxury job.

And to get benefits on gear as performant as this Accuphase you need perfect solder manufacturing, as good as Accuphase factory.

And you also need to ignore the inconvenient bathtub curve and the so-called infant mortality (aka ELF, early-life fails):
View attachment 532502
Which is why you don't see medical, military, aerospace, etc. blanket-recapping equipment. Caps have large ELF rates that require additional pre-assembly testing and quality assurance if you want the ELF risk to be less than the wear-out rate.

And my experience with the audio-recapping industry is that most gear is not done expertly. I've posted a few examples of repair-bench train-accidents, like this classic Yamaha receiver with new caps that broke the PCB due to the new caps being different size and not adequately supported.
View attachment 532504

View attachment 532505

The bathtub curve is from electronic reliability handbook MIL-HDBK-338B.

I agree there are many non-professional people, but no need to finance several thousand $ for few caps replacement in a preamp, even if it is named Accuphase.
And no need to fix what’s not broken, as always. Suggesting there are by default 100 caps and 4 days of work on that Accuphase, to revive it, is one more ripoff.

 

[MAB]

These are power filter caps seems to me to big and heavy for the PCB.
Done by an amateur.

The American amps that I have are all screw attached and with a supporting clamp on the bottom of the chassis.

The amp has perfectly adequate support for the original filter caps. The cap support clamp is clearly seen in the picture, bent aside to allow the new caps to fit. The small piece of cardboard shown in the picture was inserted to try to shore up the new caps.

This is a common problem on vintage gear refurbishments, original caps often have no direct replacement of the same size. Most techs don't have the resources to fabricate new mounting hardware, and instead ad-lib. Most also don't replace the glue used to stabilize medium-sized caps on the PCB. Many of these classic Japanese gear are incredibly well thought out, Accuphase and Yamaha being two great examples.

 

[MAB]

One of the great things about Accuphase; they are a stable company that supports their products that are distributed. They maintain a record of manufacture and service of all of the products they made since 1973. They have replacement parts for their products back to the beginning.

https://www.accuphase.com/company_profile/c_production.pdf

They are strict about out of network sales and service.

In the '80s I worked at a store in Seattle that sold Accuphase and Bryston. I couldn't afford Accuphase, so I bought Bryston, which turned out to be a stable company like Accuphase, and both supported gear for customers who bought through their channel sales. And my Bryston gear tests as new, I think in their specific categories of luxury goods, they are both great values.

 

[MLAS]

The amp has perfectly adequate support for the original filter caps. The cap support clamp is clearly seen in the picture, bent aside to allow the new caps to fit. The small piece of cardboard shown in the picture was inserted to try to shore up the new caps.

This is a common problem on vintage gear refurbishments, original caps often have no direct replacement of the same size. Most techs don't have the resources to fabricate new mounting hardware, and instead ad-lib. Most also don't replace the glue used to stabilize medium-sized caps on the PCB. Many of these classic Japanese gear are incredibly well thought out, Accuphase and Yamaha being two great examples.

I've had Yamaha M2's, Denon POA-8000's and POA-3000's and a PMA-970. Big filtercaps were always okay.
Accuphase is the pinnacle of Japanese audio design. They kept to their high standards. Would love to try a C-280 preamp and compare it with my Levinson ML-7 an Conrad Johnson PV-9a.

 

[NTTY]

One of the great things about Accuphase; they are a stable company that supports their products that are distributed. They maintain a record of manufacture and service of all of the products they made since 1973. They have replacement parts for their products back to the beginning.
View attachment 532652

https://www.accuphase.com/company_profile/c_production.pdf

They are strict about out of network sales and service.

In the '80s I worked at a store in Seattle that sold Accuphase and Bryston. I couldn't afford Accuphase, so I bought Bryston, which turned out to be a stable company like Accuphase, and both supported gear for customers who bought through their channel sales. And my Bryston gear tests as new, I think in their specific categories of luxury goods, they are both great values.

I wrote to Accuphase in Japan, asking if they could take (preventive) care of my DP-70 and, in less than 24h, I got contacted by the Swiss importer, very nice guy, who told me « On behalf of Accuphase, we don’t have any parts for this CD players, so if it still spins the silver disc, please cherish it, enjoy it, and be a happy owner »
Even if it is not the reply I was expecting, I must say this is crazy good customer support.