Marantz 8B Project

[cedus]

First let me introduce myself. This is my first post here but I have been reading this forum for years.
What I prefer in audio ? First listen to music (Jazz for 90% of it) and second build or restore audio equipment.
My current configuration is the following :
Main system :
Thorens TD124 on skelethon plinth made by myself with Ortofon RS212 tonearm and Denon DL103
2A3 SE amp fully made by myself based on SunAudio schematics
SRPP 6SN7 preamp with regulated power supply
Philips CD104
Davis Klarence kit (based on the wonderful 20TK8 and the TW26K2F but I am changing it at the moment for a bass reflex based on 20TK8 and Fountek neoCD3 tweeter)
Secondary system :
Thorens TD125 fully restored with SME3009 and Audio Technica AT95E
EL84 SE amp made by myself based on a japanese integrated amp from the 60s I stripped out (I included the RCA riaa part)
Philips CD101
Pioneer TX606
Fostex FE108ESigma in Buschhorn

I am starting this thread to share and look for help for any problem that could occure.
Lastly pardon my English but this is not my mother tongue.

 

[spartanmanor]

Welcome to AK!

Nice system. Sounds a lot like mine.

Good luck with the 8b, I am very happy with the one I have.

 

[cedus]

First pictures

So here are some pictures of the beast.
It is just in a very very bad state but let's not get desperate
First picture without the cover :

Just full of rust...
The main problem is the last owner modified it a lot :

There are holes everywhere. I will have to take care of them.

With the cover on. Still a lot of rust to take care of and those ugly capacitor I will have to change with NOS ones (already ordered from VAC amps, very nice people indeed)

 

[cedus]

Here is a view from the back :

I find it is looking less ugly from here. But still the last owner dig other holes and added plug I will have to rip out.
The base of my work will be to return it to original condition
It is an early 8B:...

... because there is this power supply outlet
but this really an 8B here is the proof :

The bias meter is perhaps the part in the best shape. I tested it with 1.5V battery and it seems to work.

 

[spartanmanor]

Wow! Looks like this one has seen better days, but it's still an 8b. I am sure you can bring her back.

 

[spartanmanor]

Here is a picture of mine next to my HK Citation I project:

 

[cedus]

Now let's see the inside. Don't be afraid... it will look better one day

The past owner disconnected the bias meter and the tube selector :tears:

And he replaced the goodall and bumble bee caps with awfull ones :

My biggest concern :

As you can see one of the selenium diode fried and with it one of the power supply resistor. Let's hope there was no bad consequence on one of the ouput transformer.

 

[cedus]

Nice setup SpartanManor. That's funny because I already ordered EH 6CA7. They are great tubes... Perhaps one day mine will look like the same.

My first task is to rip out everything nicely but making a lot of pictures to be sure to rebuild it exactly the same.
Once the case will be alone I will sand it and repaint it completely with a paint as close as possible from the original (if you have an idea where I can find this color or if you have a reference).
For info this amp is restored not for resale but to complement my 2A3 SE in my main system.
Once the chassis restored I will rewire everything as close as possible from the original.
For the caps I am going toward russian PIO. I already used them in all my amps and I am fond of them K42Y2 or K40Y9 I am still hesitating for this one. K42 seems closer with the original as this is a film cap. This other possibility is Sonicap.
For the resistors I will keep the carbon comp ones.
I will try to keep the original pots but they seem very difficult to move. This means I will have to clean them deeply (in fact like everything else).
I will keep you informed with my progress but don't be too much impatient as I am very busy on professional matters.

 

[spartanmanor]

Keep us posted.

I cheated with mine and sent it out to a shop to have it worked on. Of course it did not need that much done.

The Citation I am trying to do myself.

 

[jcmjrt]

The Citation I am trying to do myself.

Now there's a challenge!

The 8B is rough but if the iron is good, you could end up with a super amp! I wish that I could find one even if it had major cosmetic issues. Hopefully, someone will come along who has matched the paint before.

 

[spartanmanor]

Now there's a challenge!

The 8B is rough but if the iron is good, you could end up with a super amp! I wish that I could find one even if it had major cosmetic issues. Hopefully, someone will come along who has matched the paint before.

With lots of help from Jim McShane of course. When I get it done I am going to ship it off to him to give it a final once over. :thmbsp:

 

[PakProtector]

hey-Hey!!!,
That's pretty compared to one I could afford. I'm hoping for a seriously ratty one. One I can feel fine about a complete teardown, including an unwind and document job on its output transformers.
cheers,
Douglas

some safety stuff: get rid of the selenium diodes; they're poisonous upon their inevitable failure.

 

[crooner]

Excellent thread!

That's one heckuva project right there!

And I thought I had it bad when I found a non-working 8B for cheap four years ago!

The previous owner (or repair "butcher" guy) detached a whole bunch of wires and caps. It was a mess.

Managed to her back together but it was no easy task.

 

[crooner]

And finally, I decided to treat myself to a 8B in good working order, even if it meant forking some good $$$ for it.

Yesterday, I picked one up locally in very nice condition. Totally original, including tubes. The EL34s are the fabled Mullard XF2's!

 

[spartanmanor]

And finally, I decided to treat myself to a 8B in good working order, even if it meant forking some good $$$ for it.

Yesterday, I picked one up locally in very nice condition. Totally original, including tubes. The EL34s are the fabled Mullard XF2's!

She's a beauty and they will never go down in value so you can't lose.

 

[crooner]

She's a beauty and they will never go down in value so you can't lose.

Thanks!
Yours is gorgeous as well.

Always been a 8B fan. I also have a single Marantz model 2, which I hope to find a mate someday...

 

[crooner]

I certainly wish our friend cedus the best of luck restoring his Marantz.

Nice to know Kevin Hayes still sells replacement 'lytics for the 8b.

 

[cedus]

Only used ones are remaining but they are testing good with no leaking.

 

[crooner]

Yeah, the original ones were surprisingly long lived. They were part of Sprague Telephone grade range of electrolytics, easily spotted by the gray paint on the cans.

Speaking of Kevin Hayes and VAC, their 1996 monumental undertaking in bringing out the Marantz reissues is still unmatched to this day.

To me, they are the most accurate replicas ever made in this business.

 

[cedus]

Crooner perhaps you can help my project in taking a picture in the highest resolution you can of the wiring of your marantz 8B so I can have a reference picture of an untouched Marantz 8B.
My mail is ccedus and it is a gmail.com account. I don't want to give it plain for spam reason.
Thanks.
Any idea of the ref or name of the colour I shoud take for the paint ?