Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: tweedywoodpecker on November 01, 2020, 03:29:17 pm

Title: 6L6 Blackplate NOS identification help - What have I got here?
Post by: tweedywoodpecker on November 01, 2020, 03:29:17 pm

So I just received a pair of 6L6GC tubes from a seller in Germany sold as NOS RCA tubes. (Ultron used to be a company that sold relabeled tubes.) The seller told me they are from her grandfather who bought it from an electronics shop near an old US army base.

They are very well matched and sound great, the strange thing is that I can not find any tube pictures that matches these tubes. The insides look like RCA to me but they have a single top (halo) getter and a silver top. All the RCA blackplates I found have clear tops and no top getter.

So does anyone of you 6L6 buffs know what I have here?

Thanks!

Title: Re: 6L6 Blackplate NOS identification help - What have I got here?
Post by: 1blueheron on November 02, 2020, 09:39:05 am

I am not an expert but they look to me like Hitachi manufactured blackplates.   They have the top halo getter.  Ultron reportedly was a west german import/export company that relabeled anything/everything they could get their hands on.

Most RCA 6L6GC have side getter.

Supposed to sound good but won't bring the $ an RCA Blackplate would.

Title: Re: 6L6 Blackplate NOS identification help - What have I got here?
Post by: DummyLoad on November 02, 2020, 04:02:17 pm

all RCA made tubes will have the part number in a octagon.

https://www.dropbox.com/s/xp11g1ux6cmll7y/20201102_155456.jpg?dl=0



--pete

Title: Re: 6L6 Blackplate NOS identification help - What have I got here?
Post by: tweedywoodpecker on November 02, 2020, 05:51:33 pm

Thanks for your replies!

The interesting thing is that they have a top plus a side getter, but yes, I did a bit of research yesterday and also think they could be Japanese...

Edit: I think I found a match:
https://www.bangkokaudio.com/topic.php?topic=12549 (https://www.bangkokaudio.com/topic.php?topic=12549)