Yamaha b2/c70? Opinions?

[Gustav80swe]

Got back my b2 from the workshop yesterday and it sounds very good so far. Now I use it together with my as2100 as a preamp but have a c70 that I can buy at an ok price.

Someone who tried that combination?

 

[Gustav80swe]

The technician was convinced that it has been outside in the rain... Regardless, it has probably lived a hard life.

 

[clinic-audio]

 

[clinic-audio]

Outside shape is visible , but inside ??

 

[rottalpha]

The technician was convinced that it has been outside in the rain... Regardless, it has probably lived a hard life.

View attachment 1541924

probably an exaggeration, but Japan climate is very humid an most older equipment shows some signs of impact from it. I did see much worse shape gear, that came from under mud and water not just rain

Specific to B-2s, even when there is no rust or very minimal signs of it on the exterior case, if you strip the paint off, you will find more of it underneath. I think it also has to do with the way the B-2 top case paint process was executed. That is prevalent even when the amp comes from a dry and air conditioned environment, with the chassis having no other signs of corrosion.

The other thing to worry when a B-2 has signs of corrosion, is the selector switch assembly that is the B-2 Achilles' hill, that needs deep cleaning even if the amp has no signs of heavy exposure to moisture. If your tech has not performed deep cleaning of this selector assembly, it is a guarantee that you will be rubbed to some extent, of the beautiful B-2 sound.

but don't worry, if the V-fets are OK and the amp is working, everything else in there is repairable.

 

[Gustav80swe]

He told me that he's been doing some cleaning for two weeks, about five-ten times pr switch. What I been told he has a very good reputation.

He also did replace a lot of caps.

 

[rottalpha]

about five-ten times pr switch

??
like cleaned the switch by spraying it 5-10 times??
or opened the switch to clean it 5-10 times??

 

[Gustav80swe]

I dont know exactly. He said that he did clean the switches and the pots like 5-10 times.

The power button is dead, constantly on. Is it something that can be fixed or should I look for a spare?

 

[dino74]

I like using the remote for my A-S2100 .... its just too hard to get off the couch to adjust the volume.

 

[clinic-audio]

The power button is dead, constantly on. Is it something that can be fixed or should I look for a spare ?

send me a PM

 

[rottalpha]

I dont know exactly. He said that he did clean the switches and the pots like 5-10 times.

The power button is dead, constantly on. Is it something that can be fixed or should I look for a spare?

The selector switches need to be physically open and the interior oxidation cleaned with non-abrasive material. Do not need to open them more than once.
I take it that your tech sprayed switch cleaner inside 5-10 times. Unfortunately that will not resolve the oxidation issue.

no, power switch not dead.

in some B-2s the power button gets stuck to a point where it feels like impossible to move. It needs to be cleaned with a soluble to get rid of the grime, then lubed and it works like new afterwords. Have done it on more than half dozen of them.

 

[Gustav80swe]

The selector switches need to be physically open and the interior oxidation cleaned with non-abrasive material. Do not need to open them more than once.
I take it that your tech sprayed switch cleaner inside 5-10 times. Unfortunately that will not resolve the oxidation issue.

no, power switch not dead.

in some B-2s the power button gets stuck to a point where it feels like impossible to move. It needs to be cleaned with a soluble to get rid of the grime, then lubed and it works like new afterwords. Have done it on more than half dozen of them.

This is what I've got in the mail;

Hi Gustav, I'm done with your Yamaha B2, found a lot of soldering and moisture damage.
Cleaning of circuit boards / replacement of all lamps, adjustment and cleaning of all switches.
The switch has stopped working and is in the on state helat time.

 

[Gustav80swe]

Google translate tho. Originally Swedish.

 

[rottalpha]

This is what I've got in the mail;

Hi Gustav, I'm done with your Yamaha B2, found a lot of soldering and moisture damage.
Cleaning of circuit boards / replacement of all lamps, adjustment and cleaning of all switches.
The switch has stopped working and is in the on state helat time.

fair enough,

it sounds that he performed basic maintenance of the amp, including factory adjustments and basic cleaning, and left the power switch ON. If he would have opened the selector switches, he would have probably ventured to open the power switch as well....(assumption)

anyways, if the amp works and you are happy with the sound, that is all that matters. Even in original condition, (when they still work) these things sound sublime.

 

[samosui]

Gustav, nice new Yamaha units you have there. The only relatively new Yamaha component that I’ve acquired is the older CD-S2000, not counting their HT receivers.

Regarding the C-70, go for it. You’ll be able to compare old vs new then. It’s been a long time since I’ve coupled my C-80 with my B-2. What I like about the C-80 is the parametric tone control where you can adjust what band and what bandwidth to affect, or bypass altogether. I liked being able to chose exactly where and how much bass, for example, to add to NS-1000’s.

Cheers,
John

 

[aarmath]

Got back my b2 from the workshop yesterday and it sounds very good so far. Now I use it together with my as2100 as a preamp but have a c70 that I can buy at an ok price.

Someone who tried that combination?

View attachment 1541920
View attachment 1541921

 

[aarmath]

I have a similar combo. Yamaha A-S2000 being used as a preamp (connected via preamp-outs) to a Yamaha B2.
Everything else - Oppo 105D (via balanced XLRs into the 2000's XLR-ins), Google Chromecast Audio, a FiiO Bluetooth headphone amp & an Audio Technica LP240 is connected to the A-S2000.
The B2 as power amp is kept separately from the above combo and connected via unbalanced RCA connecters. Have two speaker sets (A pair of Wharfedale Dentons + Wharfedale Diamond 240s) connected to the B2.
The audio is as good as it gets. Absolutely sublime. And that's a thorough understatement.

 

[Vint Age]

The audio is as good as it gets. Absolutely sublime. And that's a thorough understatement.

Yes indeed!

 

[rottalpha]

The audio is as good as it gets. Absolutely sublime. And that's a thorough understatement.

not surprised